Master student's guide - Gps Training

SYSTEM DIVIDENDS, THE MOST EXPERIENCED GPS TRAINERS IN AMERICA

SYSTEM DIVIDENDS

APPLICATION GUIDE for Trimble Static/RTK GPS

w/Access 2014+ & Trimble

Business Center 2.99/3.40+


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ABOUT THIS GUIDE

The purpose of this training guide is to provide a practical outline and sequential framework for discussion and exploration of the Trimble suite of GPS survey grade receivers and attendant software products, with particular emphasis on the overall process of observing, computing, and adjusting high accuracy survey positions. Its focus is conceptual, not cookbook, and is not meant as a substitute or even as a complete outline of the Trimble manuals which are rich in detail and well indexed (they need to be read), but rather as a guide for discussion and introduction to the Static system. IN SHORT, THE PURPOSE HERE IS TO NAVIGATE THROUGH A PROJECT, NOT TO DOCUMENT THE ENTIRE SYSTEM.

While GPS technology is expansive beyond a surveyors dreams in terms of distances covered and precision attained, the few system restrictions are sometimes more absolute than those surveyors normally confront. When you are in a satellite shadow, you are in the dark, there is no GPS evening where you can take just one more observation in the fading light (even though GPS is a 24 hour weatherproof system). In addition, the basis of the GPS observations themselves is markedly different than conventional surveying with total stations or theodolites and EDMs, so some change in thinking of how positions (final coordinates) are determined is necessary, especially when relating the GPS results to established conventional monumentation.

The Trimble software is strong with considerable error trapping routines built in and the processing robust enough to handle most data collection situations and subsequent processing. As with all complex methodologies however, GPS observations, vector processing, and final adjustments require sound fundamentals. The most basic components and issues of the actual GPS "machinery" are briefly summarized in the following sections (detailed explanations can be found in the Trimble documentation), but the operative function of this document is to begin generating high accuracy survey positions (expressed in user specific datums and coordinate systems) with all due speed and efficiency by focusing on the overall implementation of GPS as a surveying tool.

With careful and prudent regard for the intricacies and components of the system however, GPS will serve you well. The devil is in the details, so take care of the details, or they will certainly take care of you!

NOTICE

This guide is proprietary to System Dividends. No part of this guide may be reproduced or

transmitted by any means without the express written consent

of System Dividends.

TBC COMBINED W ACCESS 3.40 - 4.DOC


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TABLE OF CONTENTS

BASIC WORKING/REFERENCE SURFACES .............................................................................. 8

TGO TO TBC CONVERSION ...................................................................................................... 12

TBC SETUP OPTIONS ................................................................................................................ 13

PROJECTS & DATA FLOW ........................................................................................................ 16

PLANNING ................................................................................................................................... 16

NAVIGATING THE ACCESS SCREENS ..................................................................................... 24

BASIC ACCESS STATIC SETTINGS .......................................................................................... 26

FIELD PROCEDURES & STARTUP – POST PROCESSED ...................................................... 31

GPS STATION OBSERVATION SHEETS ................................................................................... 34

GPS PROJECT OBSERVATION SCHEDULE ............................................................................ 35

CREATING A PROJECT ............................................................................................................. 37

DATA TRANSFER ....................................................................................................................... 42

POINT MANAGEMENT ............................................................................................................... 44

VIEWS .......................................................................................................................................... 53

USING CORS ............................................................................................................................... 62

USING OPUS ............................................................................................................................... 67

USING RTX POST PROCESSING .............................................................................................. 69

BASELINE PROCESSING & EVALUATION ............................................................................... 72

NETWORK ADJUSTMENTS ....................................................................................................... 79


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CONVENTIONAL TRAVERSE ADJUSTMENT ........................................................................... 91

CREATING/EXPORTING ALIGNMENTS .................................................................................... 96

EXPORTING .............................................................................................................................. 102

GETTING STARTED W RTK ..................................................................................................... 107

RTK SURVEY SETUP CONSIDERATIONS & ACCESS CONVENTIONS ............................... 107

BASIC ACCESS RTK SETTINGS ............................................................................................. 109

BEGINNING A SURVEY ............................................................................................................ 117

DATA COLLECTION ................................................................................................................. 134

STAKEOUT ................................................................................................................................ 142

STAKEOUT RESULT FORMATS .............................................................................................. 152

MENU DETAILS ......................................................................................................................... 153

ROADS DETAILS ...................................................................................................................... 153

JOBS MENU .............................................................................................................................. 160

KEY IN MENU ............................................................................................................................ 164

SURVEY MENU ......................................................................................................................... 166

COGO MENU ............................................................................................................................. 167

INSTRUMENT MENU ................................................................................................................ 173

INDEX ........................................................................................................................................ 175

ADDENDUMS ............................................................................................................................ 177


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GPS SURVEY SYSTEM DEFINITION & CAPABILITIES

GPS, as originally envisioned by its developer and patron (the Department of Defense), is a worldwide, all weather, highly accurate, and when fully deployed, 24 hour navigation system that has evolved into a technology with vast implications beyond military navigation. Specifically for our purposes, GPS has become a tool without peer for many of the problems facing today's surveyors, especially in regard to large scale, high order projects. With survey grade receivers such as the Trimble 4000/5000/R series, it is now possible to quickly perform high order control surveys on a scale and accuracy level never before contemplated, as well as general boundary, topo and GIS surveys on the local level. Speed and accuracy levels vary with equipment and procedures, but individual observation times of as little as 5 seconds with closures in the range of 1:500,000+ are certainly attainable without undue expenditure of resources, as are much higher closures with 1 hour observations. Trimble has further enhanced the basic positioning function of GPS by developing Real Time Kinematic (+/- 1 cm.) for topography and stake out work as well as incorporating comprehensive least squares network adjustment routines and data output options in the available software packages.

The entire system is composed primarily of three segments; the satellites themselves (Space Segment), the earth bound monitoring installations (Control Segment), and the users of the system itself (User Segment). All of these combine to provide what is essentially an extremely high order trilateration system, a technique which should be familiar to most surveyors (albeit a system with considerably more variables than land based trilateration). Essentially what is being measured is not the actual distance between the satellites (known positions) and the receiver(s) (point of intersection), but rather the number of wavelengths (integers) and travel time of the signal. From this data the "satellite to receiver" distances are computed and receiver positions derived. From these receiver positions, the survey "network" components of azimuth, distance, and height are computed and solved using least squares.

As with any navigation, survey, or spatial relation system such as a GIS, GPS requires some sort of reference point from which to relate observations. In the case of GPS, the system is referenced to ECEF coordinates which are Earth Centered, Earth Fixed (X,Y,Z) and expressed in WGS-84. After measuring a sufficient number of signals from multiple satellites with an appropriate receiver, the user is then able to compute positions relative to the system reference point (a global Point of Beginning if you will). With some further computation, these positions are processed into baselines, possibly adjusted with least squares, transformed to the ellipsoid, and may then be related to whatever historic or legal reference system was included in the observation network or a local user defined projection, i.e. northing/easting coordinates. It is useful to remember that GPS baselines are essentially the inverse result of two best fit (least square) positions, whereas conventional baselines are the result of direct observation. Both types (GPS & conventional) may be combined and then adjusted (again in the case of GPS) as a network with the least squares program available in TBC.


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STATIC/FAST STATIC GPS NETWORKS

Static GPS was the original GPS application in the survey industry and allowed on a practical level the first networks of non-intervisible points and at accuracy levels higher than conventional procedures. By occupying different points simultaneously with GPS receivers and observing/storing the transmitted code and carrier wave signals from at least 4 satellites, distances from the satellites to each receiver can be computed, trilaterated positions can be solved, and the spatial relationship of each point to another derived. In addition to the flexibility of no line of sight requirements and the super increase in relative precision, the distance capability of the system extends to tens of miles with medium effort and hundreds with additional resource. To accomplish this, an occupation campaign must be carried out which includes: simultaneous observations of at least 4 satellites; data logged at common times; and sufficient observation time vs. distance between points, all in an environment sufficiently free of electronic interference and offering a clear view of the satellites. While the receivers are fairly automated in terms of field operations (assuming good survey methods regarding instrument setups and notes), the logistics of moving personnel and equipment efficiently and profitably requires precise planning and intention – static/fast static field operations must be a concerted effort of all involved, that is to say all receivers must be operating together, not individually.

Once the data has been collected, the information is downloaded into a computer and comes together in a Trimble Business Center Project for post processing. If the field conditions were nominal the post processing is relatively automated (again assuming good survey techniques were involved in the field work and the observation environment was appropriate) and the software allows various levels of diagnostics and edit/repair tools to ferret out and eliminate bad data. Once the data has been “reduced” it is formatted in positional geodetic terms of WGS (World Geodetic System) latitude/longitude/ellipsoid height or a user defined datum such as NAD83. From this point the data must be projected to a specified coordinate system to be useful in the conventional northing/easting/elevation sense. Note that unlike conventional survey measurements, GPS measures positions and computes the component parts (azimuth/distances). This allows for some additional flexibility in network construction as the GPS networks are not as prone to the deleterious effects of ground geometry as conventional surveys.

REAL TIME KINEMATIC (RTK) GPS

Kinematic GPS is a general category or technique which employs carrier phase observations in order to compute vectors and positions, similar to the above mentioned “static” GPS. However, in contrast to the “static” method, kinematic GPS observations can be made in seconds rather than the 8 to 20 minutes required by Fast Static or the 1 hour required by the standard Static method. This time difference is obviously a tremendous advantage, but comes at a certain price which is the requirement that the “Rover” unit be able to compute and continually sustain the resolution of the integers (obtained through the measurement of the relationship between the two (+) receivers, and their relationship to the satellites). In normal post-processed kinematic surveying, this is accomplished by maintaining constant lock on at least 4 satellites during the survey, including travel time between actual observations. If satellite lock is lost by the Rover unit, the system must be reinitialized by occupying a known point (known in GPS terms) or returning to the last point surveyed (although dual frequency receivers using Kinematic mode may reinitialize after losing lock by observing an Unknown Point for approximately 8 minutes). This constant “lock” requirement is sometimes difficult, and in some environments, impossible to maintain (freeway overpasses and foliage for example). In addition, the field operator does not have results or know whether the initialization procedure was successful until the data is post processed in the office, long after the fieldwork is performed.


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To overcome these shortcomings, Trimble has developed Real Time Kinematic equipment and software that is available in several different configurations. The primary difference between the most basic RTK and post processed kinematic is that RTK has the additional requirement of a constant land based radio link between the “Base” and “Rover” units in order to differentially correct for ionospheric distortion and other systematic “noise”. While somewhat restricting, this link provides “Real Time” coordinates (both WGS84 lat/long/height and/or local values) which are obviously required for Stake Out, and the knowledge that the survey initialization (and thus the entire survey) is successful while it is being performed. Furthermore, Trimble offers an RTK configuration (available with dual frequency receivers only) that allows re-initialization to be performed either “On The Fly (OTF)” while continuing to move, or by briefly remaining stationary in any convenient location (Known Point). It must be noted however, the “OTF” mode requires a minimum 5 satellite configuration (re-initialization on a Known GPS point only requires 4 satellites, and is in one format or another the only method of re-initialization for single frequency receivers).

In all cases, kinematic surveys, whether RTK or post processed, derive “Rover” positions which

are totally relative to a “Base” station. The positions of these two receivers are the ends of “GPS vectors” (there can be as many simultaneous vectors from a single “Base” station as there are “Rovers”). While these “side shot” vectors can be projected to whatever coordinate system is required, they remain unverified, similar to topographic “side shots” observed with a total station. As a result, procedures need to be developed to periodically check the survey for errors, similar to returning to the backsight in a conventional total station survey.

As the name implies, RTK offers the operator coordinate values as they are surveyed in

real time, initially measured, formatted, and stored as WGS84 vectors from the Base

(expressed as delta x/y/z Earth Centered Earth Fixed), and then through a calibration

process transformed/projected to whatever local coordinate system is required (State

Plane, local northing/easting, etc), and importantly, also transformed to the local vertical

datum. THE CALIBRATION PROCESS IS NOT NECESSARILY DIFFICULT, BUT IT IS

ABSOLUTELY KEY TO SUCCESSFUL, ACCURATE COORDINATE PRODUCTION.

Obviously, GPS is a technology that requires many very precise and highly coordinated components AND procedures in order to resolve sub centimeter baselines from radio signals originating some 12,600 miles in earth orbit. There are many esoteric causes for position error (such as radio propagation delays due to the atmosphere, clock error, etc.), but most are handled by the receivers themselves or the software. There are however, procedures and safeguards that can taken to insure that the data collected will be appropriate and satisfy the project. The following is an outline of some of those components and procedures. However, the emphasis here is on the operational procedures, rather than the hardware components themselves or the electrical engineering inherent in the GPS system. The procedures have more user variables and are more susceptible to error or blunders (simply put, you either have appropriate, working receivers, or you don't - how they are used and the resultant data processed, may be another matter). Also, a significant portion of the system (the Space/Control Segments) is largely beyond the user's control. In fact, this guide assumes a certain leap of faith as to the notion that GPS does indeed work, and work well if properly used. As a result, it will concentrate on those areas that fall within the practical influence of the user, and the processes by which the user may be able to mitigate some of the negative effects of the GPS environment.

Successful use of GPS is due to understanding not only the individual components, but

equally important, their synergy. There are many cause and effect scenarios in this

technology, it is important to recognize the effect that one phase or procedure can have

on another.


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BASIC WORKING/REFERENCE SURFACES

WGS84

ground

Geoid (msl) Note that the geoid/ellipsoid relationship here is for the

continental US and is reversed in other parts of the world.


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GENERAL SYSTEM REQUIREMENTS & CONNECTIONS

COMPONENTS

SPACE SEGMENT

Navstar Satellites (also referred to as SVs or Space Vehicles)

When originally designed, the Space Segment was to consist of 24 satellites providing 24 hour global navigational coverage, as well as approximately 24 hours of daily 3D survey coverage (minimum of 4 satellites). Of the 24 satellites, 21 were to be in actual use, the other 3 to serve as spares that may be placed in service immediately. However, there are currently 32+ SVs in orbit and all are active and operational. The satellites are in an earth orbit of roughly 12,600 miles, and carry very precise (and very expensive) atomic cesium clocks. As any given SVs grow old, orbits decay, or other problems arise, they will be replaced.

Glonass Satellites – In addition to the US GPS satellites, the Trimble R Series receivers and TBC can observe and process the data from the Russian Glonass constellation.

CONTROL SEGMENT

The maintenance and control of the entire GPS system (the SVs themselves and the ground control stations) fall under the aegis of the Department of Defense. The DOD maintains 5 Monitor Stations around the globe to constantly track the satellites and upload new position information. As the system is primarily military, first consideration is always given to military priorities, sometimes to the detriment of civilian use (access to the system is guaranteed by Congress, accuracy is not).

USER SEGMENT

GPS Receivers, Peripherals, and Processing Software

Survey grade receivers establish positions through the trilateration of the distances from at least 4 satellites to each receiver. The distances themselves are derived through an elaborate set of computations which essentially "count" the number of whole radio wavelengths (each wavelength is exactly 19 cm in length) which are known as the integers, plus the fractional wavelength observed when the survey first begins. This technique is known as observing the carrier phase and differs from navigational GPS as well as mapping grade GPS observations (Trimble Pathfinder) in that both of these later techniques "time" the signal's journey from the satellite to the receiver to derive the distances (this method is known as code phase). The practical difference between these two methodologies is significant: carrier phase observations can be resolved to sub-centimeter levels with RTK or post processing, whereas code phase observations typically yield accuracies of 0.5 to 5 meters +/- with differential processing. How integers are observed and solved is the subject of many volumes and post graduate degrees and will not be detailed here as the principles are beyond the scope of this guide. Suffice it to say that the parameters for this method (carrier


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phase) places certain restrictions on GPS observations which will be discussed.

The minimum number of required receivers for survey precision work is 2 (operating at the same time), however, 3 or more receivers will greatly reduce the overall time necessary to complete a project, especially in the observation of a static network. In the RTK context, multiple rovers increase production arithmetically.

While specific products types and versions are mentioned below, bear in mind that this technology is rapidly changing and evolving, and care must be taken to verify compatibility issues such as product models, software/firmware versions, data formats, and communication parameters.

Trimble 4000 Series Survey Grade Receivers (SL, ST, SE, SSE, SSi,

4600LS, 4400, 4700, & 4800) and 5700/5800/R Series

Single Frequency - SL, ST, & SE Firmware Types and Processing Potential (all of the following "types" require a minimum of 4 qualified satellites, however 5 are strongly recommended to insure successful observations!!!

Standard

Static - requires approximately 1 hour observations of 4 satellites yielding the highest GPS accuracies (up to 1:5,000,000). The 4600LS, 4700/4800 & 5700/5800/R Series receivers use an internal clock to determine the minimum time required for static observations, from 20 minutes with 6+ SVs to 30 minutes for 4 SVs.

Dynamic

Kinematic - requires observations as short as 5 seconds after initialization, with constant "lock" on a minimum of 4 satellites, even when traveling between

observations. The 4600LS will only perform

Kinematic surveys using the Access Controller.

RTK (as this category of receivers is single frequency,

“On The Fly” initialization is not available) - after initialization on a known point requiring a minimum of 4 satellites (approx. 1 minute), requires approximately 2 seconds to update a position with +/- 1 cm. accuracy. Requires special firmware in addition to a ground radio link.

Dual Frequency - SST, SSE, SSi, 4400, 4700/4800, & 5700/5800/R Series Firmware Types and Processing Potential

Both Standard & Dynamic listed above as well as Fast Static.

Fast Static - approximately 8 to 20 minute observations of a minimum of 4 to 6 satellites respectively yielding medium accuracies of 1:1,000,000. (Can only be processed with TBC.)


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RTK (“On The Fly”) - in addition to the above RTK description, dual frequency receivers allow immediate initialization anywhere, not just on known points (the “OTF” option offers re-initialization while moving). However, this procedure requires 5 satellites.

Antennas (General) Internal - top mounted and coupled/interfaced to the receiver

External – Micro Centered, L1/L2 Compact, Zephyr, Zephyr Geodetic (also w/ground plane), connected by cable.

Note that L1/L2 dual frequency antennas are required for Fast

Static and OTF operations.

Data loggers (Optional for static surveys but imperative for topographic kinematic projects & required for RTK surveys)- provide easy attribute entry and control all receiver operations.

Trimble ACCESS (TSC2 - requires the ACCESS software.

Trimble Software General Functions:

Trimble Business Center (TBC) – a complete software suite to accommodate both static and real time data, including the Russian Glonass system.

Planning - provides a forecast of observation conditions, including satellite visibility

Receiver Communication & Baseline Processing (including Glonass processing) - downloads field data, reduces raw GPS files to baseline vectors and provides statistical analysis (vector quality and basic loop closures with graphics).

Network Adjustment & Data Output - allows inclusion of conventional survey data, geoid modeling, total network adjustments (GPS and terrestrial/geoid observations), and transformations to historic or local coordinate systems.

RTK data handling, feature coding for automatic map generation, surface and corridor creation as well as terrestrial data management (total station data and limited scanning files) with many stock and custom ASCII and DXF output formats available.


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TGO to TBC Conversion

TBC offers a conversion utility from existing TGO Projects. In TBC, close any open Projects, go to File/Tools/Convert TGO Project to display existing TGO Projects and highlight the required file. Select either Convert File and/or Open Project on Completion.

Note that the conversion brings the Project across in meters, and the coordinate

display is Easting/Northing regardless of the units set in TGO and the format is

Easting/Northing.


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PROJECTS & DATA FLOW

Before any discussion of actual project requirements or activities, it is essential that the operator have a familiarity with the manner in which the data is managed, and what can be done to expedite and smooth this process. It is highly recommended that the operator go through the “Tours” that are displayed on the TBC default “Start Page”.

Command Ribbon – TBC Version 2.91/3.01 allows only a customizable “ribbon layout” and Quick Access Toolbar. To custom either, right click on the “Ribbon” and select the commands

appropriate to the Tab. In the New layout dialog, optionally export the layout name and click Ok

Customizable “Ribbon”

GENERAL TBC SETUP OPTIONS under File/Options:


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File Locations – specifies default locations for Projects, data, and Templates

Internet Download – TBC allows direct connection to the Internet for various datasets (such as CORS, NGS datasheets, etc.) from a variety of sources.

When commencing a job, typically the first step is to set up a "Project" on the computer. The Project, as created under TBC will store the entire job from raw data files to final coordinate reports (including RTK data). The Project also links all the different components of the job (raw data, processed vectors, network adjustments, RTK observations, feature coding, coordinate


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systems, etc.). When the project management software is invoked and a new Project is created, the program automatically creates a database file with a vce extension and a subdirectory which will store the data as it moves through the various processing and adjustment stages. For example, for the Upland Mining Survey, there will be a database file named “Upland Mining Survey.vce” and a directory named “Upland Mining Survey”. These will be under the directory as specified in TBC in File/Options/File Locations/Project Management.

When creating a Project, in addition to setting the usual parameters such as linear units, a coordinate system must be selected. TBC includes a library of well known and used coordinate systems such as UTM and State Plane as well as a variety of commonly used datums. In addition, the software allows the user to define Local coordinate systems for specific sites, including the ability to work in existing “grid” systems projected to local “ground” values.

Raw GPS data files residing on the receiver/controller are individual observation sessions, defined as that data captured simultaneously and continuously by two or more receivers until logging is terminated by closing the file (static) or by stopping the logging activity for a particular station (Kinematic, Fast Static, RTK/Infill). Once a raw data file closed, it cannot be reopened, another file must be created.

RTK data files residing on the controller (only) are basically a chronological listings of the observations, both data capture and stakeout. These “real time” files can be opened and appended at will.

In the case of RTK, the data is already processed and the resulting positions are imported into the TBC database where the Feature Codes and attributes can be processed, including automated linework, symbology, and layering. The resulting graphics can then be exported in a variety of formats including Geodatabase XML, DWG, DXF and user defined ASCII files.

Additionally, the TBC software can import various design information (including roading data from many different design softwares) to upload to the RTK system for stakeout and construction.

The Reports routines in TBC allows report generation of any and all aspects of the project to date, including the detailed processing reports and graphs, as well as the final adjusted coordinate values in a large variety of datums, coordinate systems, and formats.


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PLANNING

As with any conventional survey project, GPS surveying requires careful planning and organization before the actual field work or processing is undertaken. Preparation is even more important in the GPS environment as a clear line of sight to the satellites is mandatory,

observation of a absolute minimum of 4 satellites is required (5+ satellites is strongly

recommended and is the practical minimum), and those satellites must be in a geometric pattern that provides strong and robust solutions (expressed as PDOP). In conventional surveying, line can often be cleared or other steps taken to facilitate measurements, but in the GPS world these remedies can rarely be invoked to "save" an observation (which is inextricably linked to other observations by time). As satellite visibility and geometry are largely out of the user's control, planning solid observation strategies and understanding system limitations becomes the key to smooth and successful completion of a project. In essence, there really is no such thing as too much planning, and to do it properly, careful consideration must be given to all aspects of the project requirements and available resources, both immediate and future.

PROJECT REQUIREMENTS-STATIC

Overall Project Goals

Similar to any conventional survey project, the procedures, manpower, and equipment to be used in GPS are dictated largely by the job specifications. If for example, State Plane coordinates rather than a local relative coordinate system are needed, then obviously suitable existing monuments must be found and included in the network or ties to CORS/OPUS generated positions must be observed. GPS positions are expressed in WGS 84 terms which can be transformed and projected to State Plane NAD 83 or a local ground system - however the accuracy (not necessarily precision) of the final coordinate system is totally dependent on the included control. This is especially true regarding vertical control as the vertical results obtained from GPS are relative to the ellipsoid, NOT the more familiar Mean Sea Level datum (known as "orthometric elevations" - the ground height above the geoid, MSL), traditionally established with gravity based instruments. Since the geoid undulates relative to the ellipsoid, there is not a constant or factor that can be applied to directly convert from one surface to the other. The relative accuracy of elevations derived from GPS is totally dependent upon how exact the "geoidal separation" between the geoid and ellipsoid can be established. As a result, special care must be given to the available vertical control in order to "model" the geoid and thus calculate the appropriate orthometric (above Mean Sea Level) elevations (if required). The geoid heights (the “geoid separation”) of the GPS positions may also be interpolated with the GEOID* model(s) available from the NGS and included in the final network adjustment. The combination of GPS with high order terrestrial observations and geoid modeling will produce the most accurate orthometric values, although the contribution of each data source is dependent on the specific conditions of the project. In addition, there are significant differences between the published NAD 27 and NAD 83 datums so the project requirements must be reconciled with the available monumentation.

If however, the project only requires the relative values of a local coordinate system, the basic control problem is far less severe. In any event, the project goals must be carefully evaluated in order to plan the survey.


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Datum & Coordinate Systems - as mentioned above, GPS is expressed in WGS 84 values, either latitude/longitude/height, or ECEF coordinates (X,Y,Z Earth Centered, Earth Fixed). In order to transform and project the measured data to meaningful local values, occupation of at least three

appropriate horizontal and four vertical monuments is required. BE SURE

TO REVIEW THE ADDENDUM AT THE END OF THIS TRAINING GUIDE

REGARDING DATUMS!

Along with the control qualifications and requirements, obviously considerable attention must be given to the points to be surveyed and their relationship to that control. Generally speaking, the control should surround the project area with some established monuments dispersed within the area (since the “orthometric” elevations are dependent in some part on interpolation from the Geoid model, the vertical control should always bound the project with whatever additional interior control is dictated by the size of the project).

“Coordinate Seeding” – due to the statistical and complex nature of establishing and resolving the “integer ambiguity” to ultimately solve for the GPS position, there can be a significant level of noise over distance if an

accurate WGS84 (LLH) position is not used as a reference (coordinate seed) in the baseline processing. This noise alone can account for up to 1 ppm (0.005’/mile) which given the far reaching arm of GPS can accumulate

rapidly. Whenever possible be sure to include a KNOWN WGS84 station in the network (NGS Control, Harn, CORS/OPUS, etc.)

NGS control information may be accessed through the NGS web page. Once the html sheet has been downloaded, it can be imported directly into the TBC Project (this includes CORS stations – see below).

Network Design Parameters

Horizontal Control - horizontal network design is essentially the same as in conventional surveying, with the noted exception of the ground geometry. Since GPS measures the positions and computes the azimuth and distance relationships the ground geometry is not as important as with a conventional system. However, the geometry of the satellites is very important.

TAKE CARE TO NOTE THE PARENTHENTICAL DATE ON THE NGS DATA SHEETS – THIS DENOTES THE DATE OF THE ADJUSTMENT. COMMON ADJUSTMENT VALUES ARE IMPERATIVE!

Strength of figure, cross ties, and all other basic network considerations must also be taken into account to yield high confidence results, as well as to provide the TBC least squares program with enough data to isolate blunders. Basically, the more frequently a point is "tied" to the network (within reason), the stronger and better conditioned is the network.

Multiple Observations (ties to multiple nodes) - as in conventional surveying, each node of the network must be tied to no less than two other points, preferably three. Remember, errors and blunders WILL occur, but if sufficient strength is present in the network, the least squares processor will commonly find and isolate the non-systematic source of error (systematic errors being those inherent in the equipment). Due to the frequency of


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antenna height errors it is recommended that each point be observed multiple times with different antenna heights.

Redundancy - regarding redundant observations (any observations that “overdetermine” a solution), statistically a re-observed baseline is really only bona fide when conditions (satellite sky positions) change enough to sustain a rigorous comparison between the data sets. Like multiple ties, redundant vectors serve to reinforce the network and allow some baselines to be disabled if necessary to refine the closure and adjustment.

CORS (Continuously Operating Reference Stations) offer free access to 24 hour operating receivers (dual frequency) to supplement and control the survey. Detailed instructions on using CORS data follows on page 62.

Vertical Control - as mentioned above, the vertical component of GPS is the least robust and requires the greatest care. If the project calls for "orthometric" elevations (above mean sea level), then sufficient control to "model" the geoid is obviously required, HOWEVER that control must also be dense enough to insure that any variations in the geoidal separation are accounted for. The vertical control stations can be supplemented with additional data from two sources, conventional leveling (both differential & "trig" values can be included in the network, complete with estimated standard errors), and from interpolating a geoid model (the NGS GEOID12a, for example). The software incorporates a full set of utilities for handling the geoid information.

While conventional leveling (both differential and "trig") is a well known technique to surveyors, implementing the geoid interpolations may be unfamiliar and bears some discussion at this point. Basically, the NGS has compiled a gravity model which "maps" the geoid undulations or gravitational anomalies. When run against the horizontal positions obtained from GPS, elevations for those points can be extracted from the model. Although the resulting elevations alone are not absolutely precise relative to the vertical datum available, when the height differences are combined with those from GPS the results approach the accuracies of conventional leveling.

All of this information can be individually weighted and adjusted with least squares, however the key to accurate elevations (as with horizontal positions) is found in "well conditioned" network construction which includes as many vertical "control" stations as is practical and profitable.

GPS Method - As mentioned above, much of GPS is relating one component to another. Choosing the method of observation requires combining the results of the Planning software, the capabilities of the available equipment, AND the overall project requirements, especially the desired accuracy. As the equipment evolves and affords shortened observation times, remember that the practical viewing requirements may increase. For example, while much faster that the Static method, Kinematic requires at least On The Fly re-initialization (dual frequency receivers) or a return to the last valid point surveyed (single frequency receivers) if the 4 satellite minimum is violated (loss of lock). Even with Fast Static, which only requires SV lock while on station, the logistics become more severe as the shortened observations require more coordination. AS MENTIONED WHEN DISCUSSING THE "USER SEGMENT", 4 QUALIFIED SATELLITES ARE REQUIRED, BUT 5+ ARE STRONGLY RECOMMENDED!!!


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THE FOLLOWING ARE NOMINAL VALUES FOR SHORT TO MEDIUM BASELINES (UP TO 20Km) – IF EXTENDED, BASELINES SHOULD INCLUDE APPROXIMATELY AN EXTRA MINUTE FOR EACH TOTAL Km OF DISTANCE.

Static - highest accuracy (1:100,000 to 1:5,000,000) requiring the longest occupations (approximately 1 hour). This procedure requires 4+ SV tracking only when on station.

Fast Static - medium accuracy (1:100,000 up to 1:1,000,000) requiring 8 to 20

minute (depending on SVs available) observations with dual frequency receivers. This procedure requires 4+ SV tracking only when on station.

Kinematic - medium accuracy (as above), but FAST (less than 10 seconds to 2 minutes, depending on the application) requiring continuous tracking of at least 4 SVs even between stations. This method requires an initialization procedure either by conducting a Fast Static session in order to observe a known baseline or OTF.

If satellite "lock" is lost, the operator must re-initialize using the On the Fly

technique available with dual frequency receivers and at least 5 satellites, or

return to a previously observed point, re-initialize, and then proceed with the

survey.

Final Network Structure - after constructing the network layout, it must then be determined as to which methods to use where and for how long, along with the logistics of access, point identification, etc.

Mixing GPS methods - employing multiple GPS methods is quite common. Generally, static methods are used to control more local kinematic/Real Time surveys which demand more stringent observation techniques.

It is important to determine unique station identification before the actual work

begins in order for the software to properly build the network. THE FIELD

CREWS NEED TO BE AWARE OF THESE POSSIBLE PROBLEMS, OBSERVATION

SCHEDULES AND FIELD NOTES GREATLY REDUCE ERRORS IN THIS AREA.


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TRIMBLE SATELLITE ACCESS PLANNING SOFTWARE (PLANNING)

The following items in bold face italics are a routine or menu option in the software/firmware or are directly related to a small group of options.

TBC allows access to Planning through the Tools menu (at this time it is not necessary to create a Project).

The Planning software is designed to provide an accurate forecast of satellite availability, both in regards to visibility and to the probable quality of the data received at any given time. Whether the SV is in view is a relatively simple forecast and can be graphed without great difficulty as seen in the Number SVs, PDOP, Skyplot, and other graphs. However, Planning also generates several reports that will consider the geometry and health of the satellites, as well as obstructions on the ground (curtains) in order to suggest the optimum observation times.

At some juncture in GPS, time and how it is referenced must be dealt with, and the Planning software is no exception. All direct GPS data, including the ephemeris used in Plan, is

referenced to 24 hour GPS time Greenwich (GPS time is not exactly the same as Universal Time Coordinated (UTC), but the difference is a matter of seconds and is irrelevant to our

purposes), even though both the receivers/controllers and software can be configured to

display 24 local time and in some instances, the 12 hour format. As noted however, most reports are in the 24 hour rather than the more familiar 12 hour am/pm format. In any event, the

time offset from Greenwich (-8 hours Pacific Standard Time, for example) MUST be set correctly in the planning software for accurate forecasts. Remember that ALL times listed internally in files from the receiver are GPS (Greenwich) time, whereas times listed in the software (especially in PLANNING) are local and dependent on the proper setting for the Time Zone Offset.

In order for the Planning results to be current the almanac/ephemeris needs to be current as well. TBC offers an automated download for the almanac under Home/Internet Download/GNSS Almanac Files/Update Trimble Planning Almanac. The ephemeris can also be obtained by running a receiver for approximately 20 minutes or going to the Trimble web site www.trimble.com/gpsdataresources.html (choose the “GPS/GLONASS almanac in Trimble Planning file format” option).

If the new ephemeris has been obtained manually (downloaded to C:\Program Files\Common Files\Trimble \Planning), open the Tools/Planning utility, select Almanac and Import the current almanac. The Internet download option automatically imports the almanac.

http://www.trimble.com/gpsdataresources.html

ftp://ftp.trimble.com/pub/eph/almanac.alm

ftp://ftp.trimble.com/pub/eph/almanac.alm


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Select Tools/Planning/File and select the Station option. Enter the pertinent location and time data – note that the local latitude/longitude can be entered manually or derived from the “City” list for cities around the world.

Use the Obstacles option to “paint” obstacles to the local observation horizon.

Graphs - Note that the following graphs can be moved and arranged on screen similar to any other Windows "window". Following are the most commonly used and useful results of the Planning software:


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On the Planning Toolbar be sure to set the Satellite Systems type appropriately

Number of Satellites - charts the number of available SVs. This graph is one of the most widely used and informative tools for observation scheduling.

DOP(s) - graphs the geometric strength of the satellites over time.


23

Skyplot - maps the satellites' movements as if the observer is looking straight up over the specified time frame and includes any defined curtains.

Occupation Schedule & Field Books (Station Observation Sheets)

After the network has been built, control researched and ultimately visited, method choices decided, and all the forecasting completed, it comes time to assemble an overall occupation schedule and forms for each occupation (see pages 34 and 35).

EVERY FIELD MEMBER SHOULD KNOW WHEN AND WHAT EVERY OTHER

FIELD MEMBER IS DOING AT ANY GIVEN TIME. It is also important to log

actual start & stop times, antenna heights and types, Station Names, file

names (Station Name & Session Name in Quick Start using 4000 receivers),

monument descriptions, and other ancillary information such as extreme

PDOPs or SNRs that occur as the survey is performed. If for example, an

antenna height is erroneously entered into the receiver, or a point miss-

named, field documentation may be the only means of saving an entire day's

work. GPS conditions such as electromagnetic sources and other

environmental conditions may also influence certain weighting parameters

later in the network adjustment software. Field Books are also a great place

for comments on equipment status (quickly draining batteries, frayed or

kinked cables, etc.).


24

NAVIGATING THE ACCESS SCREENS

The ACCESS firmware is based on the Windows Mobile PC operating system and uses a touch screen as well as keyboard input. There are 2 major desktop displays, the Main Access screen and General Survey. Under General Survey the right side menu bar displays the power level of both the TSC2 (top) and when connected, the receiver, the receiver icon, SV count, radio icon, and antenna height. In addition, tapping on the receiver icon displays the satellite screen

Similarly to Windows on a desktop, the ACCESS controller can have multiple screens/activities active simultaneously. To toggle between the open screens use Switch to (or use the Trimble

key or Trimble icon on the upper left corner), to store often used screen views use Favorites, and to return to the Main Menu screen use Menu on the right side menu bar. The Map option displays the current Job positions, the instrument locations, and allows an interface to the Stakeout routine:


25

NOTE: The ? button on the upper right corner of the screen accesses context sensitive Help files.

Under the General Access/Files there is also a link to the Windows File Explorer for file management.


26

BASIC ACCESS STATIC SETTINGS

The ACCESS SETTINGS menu parameters control how the hardware and software basically behave (fine adjustments to some of these settings can also be made during the survey as discussed later). The SETTINGS menu has the following sub menus: Survey Styles, Templates, Connect (for Internet Setup, GNSS Contacts, Auto Connect, Radio Settings & Bluetooth), Feature Libraries and Language. This sections deals with the basic settings necessary to begin an Static survey. Before beginning any survey, the parameters available in these menus must be set appropriately. Once set the various options remain in effect unless the system is cold booted.

Survey Styles- THE STYLES DICTATE HOW THE DATA COLLECTOR AND INSTRUMENT

BEHAVE DURING THE COURSE OF THE SURVEY. ONLY ONE STYLE IS IN USE AT ANY

GIVEN TIME, HOWEVER MANY STYLES CAN BE USED IN A PARTICULAR JOB.

Default Styles are: 3600 5600, Fast Static; PPK, RTK, RTK & Infill and Series S, although there may be user defined GPS styles in additional to the configuration for total stations (the 3600 5600 and VX & S Series are for Trimble Robotic Total Stations).

Survey Styles – for the purposes of a Static survey the Survey Styles would be setup as follows:


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Fast Static is a post processed survey that requires two or more receivers logging at a common rate for a common duration.

As all receivers perform the same function (that is to store raw GPS data) the only difference between a Rover and Base is file management – in a Rover file multiple observations of multiple points can be stored in a single file (usually stored in the Access Controller, in a Base file only one observation of a single point can be stored (usually stored in the receiver). In both cases, once the file is closed it cannot be reopened.

Rover options (note that the receiver should be cabled to the controller if the raw data is to be stored in the controller):

The normal logging rate is 15 seconds. Logged files may be easier to organize if the “Auto File Names” option is not used. That allows custom file naming, including a trailing file number which will be incremented automatically

Be sure the logging rate for the Rover is the same as the Base and pay special attention to the Antenna settings for both.

If the Rover receiver(s) are capable of tracking Glonass and other GNSS systems, check the appropriate boxes.


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Base options:

If the Rover receiver(s) are capable of tracking Glonass and other GNSS systems, check the appropriate boxes.

Fast Static point details:

To avoid closing an observation prematurely, do NOT use the “Auto store point” feature.


29

CONNECT/AUTO CONNECT AND BLUETOOTH – preset the connection parameters for GPS receivers, total stations, lasers, echo sounders and ASCII data transfer.

Note that a specific receiver can be assigned as a Base, likewise a specific receiver can be assigned as a Rover. This allows the appropriate connection to be made under the Instrument Menu.

To establish Bluetooth connections, press Config. Check the Turn on Bluetooth and Make device discoverable boxes and press Devices.

Tapping New Partnership or pressing Enter will start the Bluetooth search for any devices with 10 meters. Select the appropriate device and press OK, then Accept (note Trimble receivers and total stations do NOT need a passkey).


30

After the Bluetooth connections have be established, the Instrument Menu can be used to automate the connection to the Base, begin the survey, then connect to the Rover and begin the data capture/stakeout routines. As the devices are connected multiple options become automatically available


31

FIELD PROCEDURES & STARTUP

Power Considerations - the Trimble receivers ship with a variety of different power sources although all can use any 12 volt supply. Check the specifications of the equipment and be sure there is adequate voltage to run for the expected field time.

Memory considerations – as with the power supplies the Trimble receivers vary in their storage capacity. The standard logging rate for static/fast static observations is every 15 seconds so the storage burden is not great. Check the equipment specifications and be sure to clear the memory as needed.

The Access controller operations are carried out under six main menu icons each with a variety of sub options. The focus here will be under first under Settings on the main Access menu and then under General Survey/Jobs/ Measure, and Instrument.

The Access controller organizes the data in Jobs which can be created, opened, reviewed, edited and copied under the Files Menu. When a Job is created it will contain the settings of either of the following: Last Job Used, Default, or user defined Templates. For example, the Template may be preset for a State Plane Coordinate System using a specific Geoid Model, specific linked files, etc. Templates can be created, imported, edited, renamed and deleted under Settings/Templates


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Under General Survey (or Roads)/Jobs create a New Job. In this case, use the Default Template. Note that user defined Folders can be selected/created using the Select Folder icon

right of the Job Name:

Since the data collected in a post processed network is autonomous, selecting the coordinate system (grid or ground) and geoid model is not particularly important at this time. Unless the coordinate system is State Plane or UTM, click Coord. Sys. and select the No Projection/No Datum option:


33

No matter the coordinate system type or whether the system is “grid” or “ground”, a Project height is required:

Be sure to go through the Units settings and pick the appropriate values (US vs. International feet, run-rise vs. rise run ratios, for example.

Once the Job parameters have been set, press Accept to complete the Job creation process.

FIELD NOTES – following are examples of GPS Station Observation Sheets and GPS Project Observation Schedules which should supplement the electronic notes.


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PROJECT:

STATION NAME:

STATION ID:

DATE FOUND/SET:

STATION DESCRIPTION:

STATION STAMPING:

STATION ACCESS:

OBSERVER:

RECEIVER TYPE: ANTENNA TYPE:

SESSION #: FILE NAME:

LOCAL DATE: START: END:

UTC DATE: JULIAN DAY:

UTC START: UTC END:

ANTENNA DETAILS: MEASUREMENT TYPE (TRUE/UNCORRECTED):

START (1st) (2nd) (3rd) (AVG) STOP (1st) (2nd) (3rd) (AVG)

OBSTRUCTION CHART

N

LAT: LONG: HEIGHT:

ACCESS SKETCH


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PROJECT: FILE NAME: DATE: OBSERVER:

Receiver #

Station Name Obs Y/N

Receiver #


Receiver #


Receiver #


Session #

Session #

Session #

Session #

Session #

Session #

Session #

Session #

Session #

Session #

Session #

Session #

Session #

Session #

SYSTEM DIVIDENDS, "MAXIMIZING SYSTEM INVESTMENTS"

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Armed with appropriate receivers (and optionally Access Controllers), GPS Station Observation Sheets, GPS Project Observation Schedules, and a surfeit of power, the field survey can commence.

Once the survey is set in motion, the system is self tending and passive unless one of the preset tolerances is violated (PDOP mask for kinematic, for example). The operator

simply needs to know when to move to another station or end the survey. DO NOT

HOWEVER, BECOME COMPLACENT - there are several details which MUST be taken care of in order for the project to continue smoothly:

Measure the Antenna Height at least twice during the session, an incorrect

height will significantly skew the baseline results and is difficult if not

impossible to find (an additional check would be to measure the HI in

different units and cross checking the values in the field – if you are using the

Access Controller and enter 2m in the antenna height field it will convert to

6.562ft)!

Are you where you think you are? If the point is control, check the receiver position against the values on the "Observation Schedule", they should match within 10 meters +/-.

Is this where you should be for this session? Check the "Observation Schedule".

Do you have enough power (on board & spares)?

Did you enter the appropriate Station Name?

Did you spell it correctly (or at least the same as before)?

Are you sure about the Antenna Height?

What kind of Antenna are you using? If the antenna is external, check the label on the antenna itself.

How long should you be here? REMEMBER ALL RECEIVERS MUST WORK IN

CONCERT, THE LAST RECEIVER ON STATION STARTS THE CLOCK,

HOWEVER THE RECEIVER WITH THE FEWEST SVs CONTROLS THE CLOCK!

THIS MEANS TIGHT COORDINATION WITH ALL OTHER TEAM MEMBERS!!!!

And is it time to go? To Where? By When? Check the "Observation Schedule".

Obviously, some sort of communication between receivers will be

advantageous in almost any GPS control scenario. However, as the

occupation times become shorter and timing more critical, radio handsets or

mobile phones become imperative.

Once the daily files have been closed, download them, BACK THEM UP, AND PROCESS

THE VECTORS AS SOON AS POSSIBLE TO ASCERTAIN WHETHER OR NOT ANY POINTS

NEED TO BE RE-OBSERVED. DO NOT DELETE FILES FROM THE RECEIVERS UNTIL YOU

ARE SURE THE DOWNLOAD HAS BEEN SUCCESSFUL AND BACKUPS HAVE BEEN

MADE!!!


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CREATING A PROJECT IN TBC

The database in TBC is referred to as a Project where all data associated with a particular site is stored. After the Project is created and saved there will be a database file named *.vce and a Folder with the same name. The location of all Files and Folders is set under File/Options/File Locations. All imported files are contained in the Folder. When creating a Project, Templates are used for pre-set variables such as Datums/Coordinate Systems, Units, Computational Settings, Baseline Processing parameters, and Network Adjustment settings. Since it is unlikely that the Trimble defaults will be totally appropriate for individual user requirements, and since there are so many different settings, it is recommended that custom Templates be created (for example, a Template using a specific State Plane coordinate system, in US Feet, using Glonass, etc). This is easily accomplished by using the File/Save Project As Template option at the appropriate stage in the following Project creation process:

Once a Project has been created, the various Project Settings can be modified by selecting the

“gear” symbol ( ) from the Quick Access Toolbar:


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Project Settings/Coordinate System

Project Settings/Coordinate System/Local Site – allows scaling ellipsoid grid to ground.

Project Settings/Units


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Project Settings/Computational Settings

PAY PARTICULAR ATTENTION TO THE MERGE ON IMPORT OPTIONS (also see page 43)


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Project Settings/Baseline Processing

Project Settings/Network Adjustment


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Project Settings/Default Standard Errors

Once the Project has been created, go to File/Save Project As. Otherwise, all Project settings, data, etc. are stored in a folder titled “Unnamed”. Additionally, be aware that any and all Project changes are only stored when the File/Save Project option is used or when clicking Yes on exiting TBC.


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DATA TRANSFER

Downloading the field data to the computer and transferring it to the TBC database is set up to be mostly automatic and is done through the Device icon option under the Data tab to copy files from an external device (Controllers and receivers). In the case of the external devices, data transfer is controlled by the TBC software while the ACCESS controller/receivers are tasked in slave mode.

NOTE: THE DC FILE FORMAT IS NO LONGER FULLY SUPPORTED BY TBC!!!! WHILE IT IS POSSIBLE TO IMPORT A DC FILE INTO TBC THERE ARE MULTIPLE SITUATIONS WHERE THE DATA WILL BE INCORRECT!!!! TO INSURE THAT THE DATA IS CORRECT, ONLY USE THE JOB FILE FORMAT!!!! THE DC FILE MAY HOWEVER BE IMPORTANT AS ELECTRONIC FIELD NOTES!!!!

When downloading from an external device TBC has two slightly different modes: if the device is a Access Controller it uses Microsoft ActiveSync/MDC (Mobile Device Center in Windows 7) for

the communication, the Device Pane opens automatically when the connection is made; if the device is an earlier Controller version or a receiver, the device must be selected from a list (which can be edited by using the Options key). If the data is raw GPS data (static or Infill files for example) the Raw Data Checkin spreadsheet will automatically be displayed and allow point id and antenna edits. However, if the file contains Access controller Job data, that information is immediately imported into the TBC database and reduced.

TRANSFER/IMPORT DIRECTLY TO A TBC PROJECT

The procedure for the operation requires that a TBC Project be open before the download transfer process is begun (files can be uploaded from the computer to the device without the Project being open). Once the external device is connected the Device Pane will display the directory structure, simply highlight the desired file (Job or T02) and either use the Import button or “drag and drop” the file into the Project.

NOTES:

Raw data files (DAT or T02) will be under the Other Files folder on the Controller


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The Process Features Codes on Import option under Project/Project Settings/Feature Code Processing allows for the feature code processing to be automatic when data is imported into the database. Likewise the Send eligible static occupation file to RTX on import will automatically begin the RTX post processing option.

While the GPS Site Calibration can be re-computed as many times as necessary in either the ACCESS or TBC the Import process will prompt the operator to choose between the current calibration/coordinate system in the ACCESS or the TBC database if the calibrations/coordinate systems differ or if the TBC database has not yet been calibrated (as in the case of the TYPE 1 survey discussed earlier in this guide).

BEAR IN MIND THE PROJECTION/TRANSFORMATION/CALIBRATION ISSUES DISCUSSED

EARLIER UNDER THE BEGINNING A SURVEY SECTION OF THIS APPLICATION GUIDE.

Once the definition choice has been made (either convert to the data collector definition or keep existing project definition), the points and vectors (both GPS and total station) will be

displayed on the screen. IF THE BASE WAS STARTED USING THE HERE KEY AND OPUS

SOLUTION(s) WILL BE USED TO BRING ACCURACY TO THE PROJECT, GO TO PAGE 67

BEFORE PROCEEDING!

TRANSFER/IMPORT USING THE STANDALONE DATA TRANSFER PROGRAM

Initially, the Data Transfer program needs to be setup on the Windows Desktop. Go to C:\Program Files\Common Files\Trimble\Data Transfer and right click on DataXfer.exe and “Send to Desktop” as a shortcut.

To begin this process, start a New Project in TBC (see on page 120) if necessary, NOTING that a myriad of defaults can be set in the templates to insure consistency in coordinate systems, etc. Once the Project has been created, complete the following:

Select Data Transfer from the Desktop, this will default connect if possible to any connected device or allow the user to select the device being downloaded (GPS receiver, PC Card, Access Controller which is listed as General Survey, etc.). Once the connection has be established, select direction (Send/Receive). Select the Add option and the screen will display the available types/files in the Controller. AT THIS POINT BE SURE TO SELECT THE DIRECTORY OF THE APPROPRIATE PROJECT AS THE DESTINATION AT THE BOTTOM OF THE DIALOG BOX. Highlight the desired file(s) and press the Open button on the dialog box, this action will put the selected file(s) in the File Names category. Press Add/Open to add the files to the list, then Transfer All in the dialog box and the data will be copied from the Controller to the user defined directory location. (Note that the transfer is a copy, not a move command, the downloaded files still exist in the survey device).

IF THE BASE WAS STARTED USING THE HERE KEY AND OPUS SOLUTION(s) WILL BE

USED TO BRING ACCURACY TO THE PROJECT, GO TO PAGE 67 BEFORE PROCEEDING!

In TBC, select Import either from the File pull down or the icon on the toolbar. On the Import dialog box select the Project directory and the downloaded files will be displayed.

NOTE: In the case of Infill or other post processed data (*.dat files only), the file OR MULTIPLE FILES can be selected in the Import dialog box and the Import option executed. This will subsequently open a spreadsheet type editor prior to the data reaching the database.


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POINT MANAGEMENT:

DUPLICATE POINTS, MULTIPLE OBSERVATIONS TO A POINT, MUTILPLE DOWNLOADS

OF SAME DATA COLLECTOR FILES:

WHILE CONSIDERING THE FOLLOWING ISSUES, BE SURE TO DISTINGUISH BETWEEN OBSERVATIONS AND POSITIONS DERIVED FROM THOSE OBSERVATIONS – ALSO BE SURE TO CONSULT THE LATEST TRIMBLE MANUALS AND README FILES.

Accidental and deliberate occurrences of station point names have long been an issue with field files and office database files. The Access Controller internally handles the problem using data types (post processed data or RTK), classifications (the highest in class determines the point used).

TBC has several other issues however, not the least of which is downloading an ongoing RTK file multiple times, potentially creating many copies of the same point/position.

Basically the highest classification of a particular point is the default TBC display

(Control, Survey, Mapping, and Unknown) which have different icons in the point properties box. This behavior is essentially the same as in the Access Controller and fine as far as it goes and accounts for observations from the field deferring (at least initially) to Control positions imported from an ASCII file or NGS data sheet for example. However as the points may come from a variety of sources, undergo several different levels of processing, adjustment, etc., TBC must have additional rules governing the current position for any given point.

1. If a station has a point quality of Control, that position trumps any other position, that is to say both positions are in the database but only the control value will be listed in the reports and exported. If duplicate points are found in the database and one is Control and the other of a lower classification and the Merge Duplicate points option is executed, the lower class will move to the Control position. If duplicate points are imported with the same classification (Control for example), the

points will merge and the latest position will be used. If the tolerances under Project Settings/ Computational Settings/Point Tolerances are violated, the point will be red under the Project Explorer and it will be Flagged on the screen and listed under the Flags Pane. Both positions are in the database however and either one can be deleted.

2. There is another level to the point positions well, in the Trimble geodetic world there are Grid, Local (NAD83 for example) and Global (WGS84). Unless told otherwise TBC treats Local and Global as being the same (they are NOT). All types can be keyed in, but only once. However, multiple versions of the same type can be imported (but not in the case of DAT/T01 files, see below – RTK files can however be imported multiple times).

3. DAT/T01 files have a particular status since they contain raw positions that have not yet been processed. In the case of a Static survey, points will be imported numerous times and MUST be named the same even though the files have somewhat different positions. In this case the latest (although temporary) position is used if the point does not have another position of a higher quality. However, this is ultimately moot since after processing and adjustment a single position will be created with an Adjustment quality level.


45

Computations/Sideshots allows multiple methods to mean field observations:

The Merge on Import option under Project Settings/Computations/Point Tolerances provides default settings to control duplicate point merge criteria.

When importing duplicate point names the following screen appears, if the incoming points are within the specified tolerance the Merge column will be checked, if the specified tolerance is violated the Merge column will not be set – the user may override the automatic segregation by

checking/unchecking the Merge column. The following options are available:

By Point Tolerance x3 - Merge the points if their positions are within three times the

specified quality point tolerance in Project Settings (see above).

By Point Tolerance - Merge the points if their positions are within the specified quality

point tolerance in Project Settings (see above).

By Custom Tolerance - Merge the points if their positions are within the point tolerance

specified in the fields located beneath the Merge options drop-down.

By Station Point - Merge the points if one of them is a station point, regardless of their

positions. NOTE – the tolerances here are the same as those for the Custom Tolerance.


46

If the tolerances are violated the following dialog boxes offers the ability to selectively

Merge points outside the tolerance:


47

MULTIPLE DOWNLOADS OF THE SAME RTK DATA FILE

Obviously, this data flow can get very complicated!

BOTTOM LINE – WHEN DEALING WITH MULTIPLE POSITION SOURCES

(IMPORTED, KEYED IN, ADJUSTED, OR MERGED) BE SURE TO REVIEW THE

POINT “HISTORY” UNDER THE PROJECT EXPLORER.


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From this point forward, many options are available: plane transformations or other survey manipulations (including re-calibrations as mentioned above); or data export in the form of ascii files (using a list of common ascii or custom formats) or drawing files (DXF or DWG formats).

NOTE: if the “Feature Code on Import” option was selected when the Project was created, the line work, symbology, layering, and point attribute metadata will have been automatically processed.

Once the data has been downloaded and imported, TBC will automatically display a Plan View of the dataset.

POINT SELECTION(s)

SELECT/Select Points and Advanced Select – basically the Select Points option is more rigid in that other than the software provided selections the user can only introduce limited filters (wildcards, partial strings, etc). Advanced Select allows for the user to specify a Data Type (Multiple Data Types, Points, Coordinates, etc) and then allows specific interrogation of details

using criteria like Not Equal To Regular Expression, Not Equal, Equal and Equal to Regular Expression, with user input values. Note that the expressions used in TBC are international rather than Microsoft - see Select Using Advanced Criteria under Help for complete options.


49

For example, under Select Points entering 1…301 in the Point ID field will return points 1 through 301 and 1…301,707…710 will return points 1 though 301 and 707 through 709. Entering a value in the Feature Code field however requires and exact match.

Using Advanced Select allows expressions such as Data Type Point with a Point ID that equals a regular Expression with a value of 3 returns any point whose ID contains a 3 anywhere in the ID:

Whereas a value of ^3 returns only those IDs that have a 3 in the first position of the ID.


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Using the Point Spreadsheet will also allow point filtering in the context of columns selected to be displayed under Project Settings.

Note that clicking on the filter icon next to a particular column and selecting Custom allows the spreadsheet to be filtered with common expressions: equal, less than, etc. and clicking a column title will sort the column.


51

“Exploding” points – under certain conditions if two or more Points have been merged the merge

can be reversed. How and if they can be reversed is also a function of where they were merged, in the data collector, during the Import routine, or in the TBC database. To determine whether a

Point can be exploded, go to the Project Explorer and click the + beside the point, if there are multiple observations for the point double click on a particular observation and the Properties box will display, then rename the Point for that observation – after the Compute Project option is exercised the original/separate observations will be available. In the following case 1627 and 1033 were merged as Point 1033, by selecting and expanding Point 1033 in the Project Explorer and then right clicking for the Properties of the appropriate Vector the Point can be renamed back to its original designation, then Compute Project is executed the original positions of both 1033 and 1627 will be restored.


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Multiple Edits (NOTE that when multiple element types are selected the available editable fields if available at all become more limited as the differences in the types increases) – when common elements are selected (Points OR Vectors for example) opening the Selection Explorer and right clicking on the highlighted elements allows editing any fields with a blue font. The available fields (blue fonts) will vary depending on the type of element selected. In the following example the Vectors were selected and the antenna height will be changed to 7.00’ when Compute Project is executed (Antenna Heights can also be selected using Occupations):


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TBC Views

TBC allows several different “Views” and Spreadsheets of the database, all of which present various aspects of the survey data. The Plan view is the default. The Project Explorer allows access to Points, Surfaces, Imported Files, etc. Note that the spreadsheets can be copied and pasted to external programs (see Page 103).

Plan View – graphic display of the survey data

Note that TBC uses the standard AutoCAD convention of a “window” and “crossing” when selecting items on the screen. If the selection box is drawn left to right (the box will be a solid line), only those items that fall completely in the box are selected. If the selection box is drawn from right to left (the box will be a dashed line), any element(s) that “cross” the box are selected.

Window selection Crossing Selection


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Plan View also allows georeferenced background images (.bmp, .gif, .jpg, .png, .tif) to be imported and displayed along with the survey data. The coordinate system and units in the world file which references the image MUST be the same as the TBC Project.

Once the image has been imported it’s position can be refined by using the Image/Georeference Image option which allows pixel points to be shifted to survey point positions.


55

3D View

3D Drive

3D drive is available when a corridor has been constructed and allows a drive through


56

Points Spreadsheet – details the points and allows Id and Feature Code edits (NOTE: under Settings/View/Points Spreadsheet the following can be set to “Show/Hide”; Pt ID, Feature Code, Attributes, Northing, Easting, Elevation, Local Lat/Long, Local Height, Global Lat/Long, Global Height, ECEF XYZ Coordinates, Projection/Height/Combined scale factors and Convergence angle.

Vector Spreadsheet – displays vector details and allows enable/disable. (NOTE: under Settings/View/Vector Spreadsheet the following can be set to “Show/Hide”; Vector ID, To/From Point ID(s), Status, Horizontal/Vertical Precision, Azimuth, Ellipsoid Distance, delta Height, Solution Type, Field Method, delta ECEF XYZ, Maximum PDOP, all Antenna details, Start/End times and duration.


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Optical Spreadsheet - displays total station details details and allows enable/disable. (NOTE: under Settings/View/Optical Spreadsheet the following can be set to “Show/Hide”; Observation ID, Station ID, Orientation ID, Observation Type, Status, 1st Backsight, From Pt ID, To Point ID, Feature Code, Observed Data, Computed Data, Instrument Height, Method, Instrument Model, Target Height, Method, Prism Type, and Backsight.

Occupation Spreadsheet – individual setup details w/antenna detail editing. (NOTE: under Settings/View/Vector Spreadsheet the following can be set to “Show/Hide”; Point ID, Start/End times, Duration, Epochs, Field Method, File Name and all Antenna details.


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Time Based View – displays vectors by time and allows enable/disable

Note that multiple “Views” can be open simultaneously and may be accessed from the tabs at the top of the screen.

In addition to the spreadsheet “Views” the Session Editor displays the observed satellites (including the Glonass SVs if the T01 file was imported – the Glonass SVs have an “R” prefix whereas the GPS SVs have a “G”). This View is only available for post processed data.


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GOOGLE EARTH LINK Selecting any database object and then executing the View/Google Earth option or using the

Google icon display an option screen which allows offsets to rectify the coordinates as well as “clamping” any linework to the ground in 3D perspective:

Pressing APPLY will automatically open Google Earth and display the database objects, including any photo attributes:


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Project Explorer - allows access to Points, Sessions, Surfaces, Imported Files, etc.

View Filter Manager - allows filters for Raw Data, Flags, Layers, Points, Observations, and GNSS Data Types


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Selection Explorer – text list and properties of current selections

Device Pane – creates/lists direct connection devices for data upload/download (note ActiveSync/MDC devices do not appear on the Device Pane, the connection is automatic when ActiveSync/MDC is live.

Flags Pane – text description of error flags


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USING CORS

TBC allows both an automated and a semi automated connection to the CORS website with the Internet Download option.

To setup the automated connection to a specific CORS site go to File/Internet Download and execute the following (this option requires that the local GPS data has been imported into the Project):

1. Use the Internet Download Configuration icon , highlight the Reference Stations option and select New Site. Use the “Download the most up-to-date list” option to obtain the latest stations. This will update the Reference Stations list.


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2. Once that is complete press New Site and highlight the appropriate Station from the list and press OK (note that the list can be sorted by distance from the Project). Press OK.

3. Select the Station from the Reference Station section and press Automatic at the bottom of the dialog box. This will display the time slice for the GPS data in the database.


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4. Press OK or select the User Input option to manually set the time frame. Then press OK to initiate the download process and automatically import the RINEX files and datasheet. It does NOT include the precise ephemeris (that needs to be done under the Precise Orbits section).To setup the manual connection for the CORS Map site and the “User Friendly CORS” from the NGS go to File/Internet Download and execute the following:

1. Using the Internet Download Configuration icon select “New Site” and Enter the Details Manually options, for the Site Name type “CORS Maps”, for the Manual Connection Host URL/Address type http://www.ngs.noaa.gov/CORS/cors-data.html, then select OK.

2. Repeat step 1 using “CORS Download” for the Site Name and using http://www.ngs.noaa.gov/UFCORS/ for the Manual Connection Host URL/Address.

http://www.ngs.noaa.gov/CORS/cors-data.html

http://www.ngs.noaa.gov/UFCORS/


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3. To select and download the CORS data, begin by browsing on the observed data points to ascertain the time segments needed for the CORS stations. Go to File/Internet Download and select the CORS Maps option to review and identify the station appropriate for your use. (NOTE: In most cases the CORS stations are significantly distant from your local site – to compensate for the longer distances you should extend your local observation times by at least 1 minute for each kilometer in distance).

4. After determining the appropriate stations, go to File/Internet Download and select the

CORS Download option, then execute the following:USER FRIENDLY CORS – this option asks for the local time, start time, and how many hours of data are required.


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5. After selecting these items, select “CONTINUE” and another screen will be displayed offering a selection of available CORS stations listed alphabetically by the four character station name as displayed on the map. Select the appropriate station, check the NGS data sheet and the IGS Orbits (the precise ephemeris) options, and click the “SUBMIT” button.

6. The server will compile a ZIP file for download that contains all the information necessary for processing (there will be a file with an extension ending with an “o” which is the data file and one with an extension ending with “n” which is the broadcast ephemeris file, plus the data sheet for the ARP with a .ds extension, as well as the Precise Ephemeris in SP3 format). Save the ZIP file in the folder of the TBC Project.

7. Once the ZIP files have been downloaded, they can be directly imported into TBC. (TBC will unzip the compressed files and extract the *.*O, *.*N RINEX files, the *.ds data sheets, and the precise ephemeris files even though there may be error messages for the various log files). From this point forward, treat the CORS data as you would the Trimble *.dat/T01 files for processing and adjustment.


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USING OPUS

If the RTK&Infill Survey Style was used in the field, the raw GPS file at the Base can be sent to OPUS to bring accuracy to the survey (required for State Plane, UTM, etc). The Infill option also allows Rover points to be observed outside the connection from the Base station (or VRS cell connection).

TBC has now simplified the entire OPUS submittal process. Once the raw data file (*.dat, *.T01, *.T02) has been downloaded, go to the File/TCC pull down menu in TBC, select Trimble

Access Services/Survey Tools and then the Data Processing option. Then complete the prompts: browse for the file; select the appropriate service (OPUS Static); confirm the point ID, antenna type, antenna measurement type and antenna height; then provide the appropriate email address for the return and press Send.

The results will be emailed to the address provided, usually within 30 minutes. Open the email and review the results. Be sure the % of data used and the RMS values are within the project tolerance, then save the XML attachment to the TBC Project directory.

Open the Project, select Import. Select the Project directory and the XML file. Using the OPUS/XML import in TBC 2.30+ will only allow the Local (most often in the US, NAD83) position. If ITRF is required, it must be keyed in. Click Import and the following screen will appear:


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After the OPUS return has been imported, the Base point is now accurate, HOWEVER IT WILL BE NECESSARY TO USE THE PROJECT EXPLORER TO RENAME THE OPUS POSITION THE SAME AS THE BASE POINT ID USED IN THE FIELD AND TO CREATE A WGS84 POSITION AT THAT POINT WITH THE STATUS OF CONTROL.

Open Project Explorer and browse the OPUS point to show Properties and rename the point to match the Base point ID in the field. Right click on the point in Project Explorer and use the Add Coordinate command, choose Global for the Coordinate Type and set the status to Control. The Global classification is required if the points is to be used in any sort of Site Calibration.

Once this is completed, import the Job file and if necessary merge the multiple Base points.

NOTE: with some Trimble receivers the raw data file (DAT, T01, & T02) for the Base which contains the AUTONOMOUS point position will come into TBC as a CONTROL point. When TBC sees the position conflict between the existing OPUS position and the autonomous

position it will open the Merge on Import screen and if checked it will import the data file BUT

SINCE IT IS CONTROL AND IT IS THE LATEST IMPORT, THE AUTONOMOUS POSITION

WILL BE HELD – THAT IS TO SAY, THE SURVEY IS NOW BASED ON THE

AUTONOMOUS RATHER THAN THE OPUS POSITION. TO FIX THIS PROBLEM, GO TO

THE POINT MANAGER AND RECLASSIFY THE DATA SOURCE (DAT, T01 OR T02)

QUALITY TO “UNKNOWN” AND THEN RECOMPUTE THE PROJECT, OR IMPORT THE

RAW DATA FILE BEFORE THE OPUS VALUES.


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USING RTX POST PROCESSING

Although TBC semi automates the OPUS procedure as described above, with TBC version 3.10/2.95+ the process can be automated further through RTX-PP (see http://www.trimblertx.com/Support.aspx for tech details). RTX-PP processes the raw static data on importing the *.DAT/*.T02 files and imports the results as the appropriate Point ID.

Under Project Settings/RTX-Post Processing several options are displayed:

The Coordinate System/Tectonic Plate options offers Datum and Plate selection (if different from the Project values) and Import Results allows either Local or Global values:

Importing a DAT/T02 file and selecting the Send To RTX-PP option will automatically begin the post processing on import, show the results, and allow importing the position to the Project:

http://www.trimblertx.com/Support.aspx


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The RXT meta data can be viewed under the Project Explorer/Imported Files:

NOTE: BE SURE TO CHECK THE QUALITY OF THE IMPORTED RAW DATA FILE (DAT/T02), IN MANY CASES IT MAY COME IN AS CONTROL WHICH WILL TAKE PRECEDENCE OVER THE RTX POSITION WHICH IMPORTS AS SURVEY QUALITY. IF THE RTX POSITION IS TO BE USED, EDIT BOTH THE DAT/T02 AND RTX POSITIONS AND REVERSE THEIR QUALITY STATUS (IE CHANGE THE DAT/T02 CONTROL QUALITY TO UNKNOWN AND CHANGE THE RTX SURVEY QUALITY TO CONTROL AND PERFORM A RECOMPUTE).

CHANGE RAW DAT/T02 FILE FROM CONTROL TO UNKNOWN:

CHANGE RTX IMPORT FROM SURVEY TO CONTROL:

BE SURE TO RUN THE RECOMPUTE TO FINALIZE THE POSITION!


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Editing the RTK&Infill Base in ACCESS

If the RTK&Infill Base was started with the “Here” position and the OPUS corrected solution if available the edit may be made in the data collector as follows:

Go to Files/Point Manager and browse to the Base point, click Edit at the bottom of the screen and then choose Coordinates as below:

Once the Base has been edited ALL observed points have been corrected to the accuracy of

the OPUS position. NOTE THAT ANY GRID POINTS WILL NOT MOVE!


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BASELINE PROCESSING & EVALUATION

Once the data has been downloaded and vetted, the Survey/Baseline Processing option is used to compute the vectors as per the Project Settings/Baseline Processing parameters (see page 40).

The Time – Based View displays the common satellite times for each vector and allows access to the Session Editor to edit individual SV time:


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Selecting the Baseline Processing icon or the option under Survey, processes the raw data files with the following display/report:

Review processing results during processing (as the baselines process, the summary results are displayed), check solution type, ratio, and RMS, note “suspect” baselines with marginal results. This particular screen report is NOT available later. A Baseline Processing Report is available by double clicking on the desired baseline and is available at any time in the future.

Solution Type - the WAVE processor produces are Fixed, Phase/Code Float, Triple Difference, and Code Solution. Generally speaking, the iono free fixed solutions are best, especially for longer baselines. L1 only solutions usually have lower noise levels on short baselines.

Ratio - the ratio of the sum of squares of the last solution relative to the previous solution. Higher values indicate higher relative quality. The default cutoff value for this test is any value below 1.5. (NOTE: code, triple, float, and kinematic solutions do not list ratios).

RMS - the root mean square error in the final evaluation of the baseline.

If the statistics are acceptable, Save baselines to exit the Process Baselines screen. At this point, the Processing Summary Report is available under Reports. (NOTE: under Reports/Report Options/Baseline Processing Report the following can be set to Show/Hide: Occupation Start/Stop time, Solution Type, Horizontal/Vertical precision, ECEF delta XYZ, Geodetic azimuth, Ellipsoid distance, delta Height, Processing Start/Stop times, Satellite Available, Baseline Summary, Baseline components, Standard Errors, Covariant Matrix, Occupations, Tracking summary, Residuals, Messages, Processing Style, and Errors.


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The Tracking summary and SV residuals offer graphic insight as to processing anomalies and errors:


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The Vector Spreadsheet also allows an evaluation/editing of the results:


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If necessary, the Sessions Editor allows edits of an entire SV data stream or specified segments. Segments are re-defined by “drawing” a box with the mouse over the particular time slice.

Once the baselines appear to be statistically acceptable they must be tested as either individual polygons or as the entire network.


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LOOP CLOSURES

If the baseline statistics are acceptable, the next step is to test how well they fit together in a network, and then how well the network fits with the control (remember the baseline statistics only refer to the individual elements, not the network). In some cases, it may be easier to test the network by first testing any and all polygons that are formed in the network (in complex networks the number of potential loops becomes so large as to be unmanageable, if so proceed to the Minimally Constrained Adjustment on page 81). To test the integrity of the measurements within themselves, the Loop Closure Report is available from the icon or under Reports/Loop Closure Results:

The Pass/Fail criteria and desired number of legs in each loop can be set under Reports/Report Options.

Use the Failed Loops and Observations/Occupations in Failed Loops sections to isolate field blunders like antenna heights.


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If blunders are found, antenna heights for example, they can be edited in the Occupation Spreadsheet. In those cases, the processing for the effected baselines will be cleared and they must be re-processed.

Once the baselines prove to be at least nominal within themselves, the next procedure is the Network Adjustment.


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NETWORK ADJUSTMENTS & TRANSFORMATIONS

Having arrived at the point where the baselines have been calculated and scrutinized as to

their quality, it comes time to put all the parts together and test the fit of the network.

Generally speaking, the adjustment phase consists of the following steps: independently

building and testing specific network types (GPS and conventional); transforming the

networks to the desired datum, coordinate system, and units (this can be done at any

time); combining the two networks if terrestrial data is present; employing whatever

elevation tactic is appropriate for the project specifications (geoid modeling); weighting

the various components, re-adjusting the entire combined network, and FINALLY

EXPORTING COORDINATES!!!

TRIMBLE LEAST SQUARES NETWORK ADJUSTMENT (UNDER "SURVEY/ADJUST

NETWORK" IN TBC)

As the Project enters the network adjustment phase, the variables that can be employed by the user can increase dramatically as GPS may not be the only source of survey information to be included in the project. In addition to the ability to add terrestrial and geoid observations to the baselines obtained by GPS (with both of their various weighting strategies, etc.), TBC also allows a whole host of combinations of fixed positions, datums, and coordinate systems. There is however a certain basic flow through TBC as outlined below

When going through the adjustment process, a total of three adjustments should be performed: a minimally constrained adjustment to test only the observations within themselves, a fully constrained horizontal adjustment to test the network against the chosen horizontal control, and finally a fully constrained fully combined adjustment against all of the pertinent control (horizontal and vertical). While somewhat more time consuming than a single fully combined fully constrained adjustment, this method allows a much easier evaluation and detection of error: if the first adjustment is satisfactory, the measurements are reliable although erroneous points (reference monuments for example) could have been observed; if the second adjustment works out, not only are the measurements reliable but they fit the horizontal control (eliminating the possibility of wrong point measurement), and if the final fully constrained adjustment which includes the vertical control passes scrutiny, there should be a high degree of confidence that the survey was conducted properly. In the case of blunders (antenna heights, wrong stations, etc) or bad control (subsidence, frost heave, etc), the three stage adjustment process will make troubleshooting much easier.

ADJUSTMENT/RESULTS

DOCUMENTATION All reports, including the Adjustment Report are in HTML format but can be saved in other formats (when a Report is displayed, go to File to Save, Save As, etc.) In order to document each of the following adjustment phases, the Adjustment Report should be saved with a specific name at each appropriate iteration.


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Under Project Settings switches are available to set the estimated setup error (antenna measurement error and centering) as well as the adjustment confidence error (Sigma)


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MINIMALLY CONSTRAINED ADJUSTMENT

The initial adjustment holding only one horizontal point fixed tests the integrity of the measurements within themselves, without the constraint of outside values (precision).

Set the horizontal control point to be constrained using SURVEY/ADJUST NETWORK/FIXED COORDINATES. Note that only points that have Control quality value are listed and only the control component is available.

ADJUST (this will be an minimally constrained adjustment, testing the network on its

own merits without the possible “noise” inherent in “fixed” control values )

Once the Adjustment has been performed, the Adjust Network box will display a brief summary of the results.


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Reference Factor - should be close to 1. If less than one, network is more precise than the assumed errors. If greater than 1, the network errors are actually larger than presumed from the a priori errors established from the baseline processor, in either case the Chi Square test must pass before proceeding to the next adjustment.

Chi-Square Test - (Pass/Fail) a consideration of the weighted squares of the residuals, and the number of degrees of freedom. This test "passes" when the Reference Factor is in an acceptable range around 1

Use the REPORTS/Network Adjustment Report to determine the statistical quality of the network in more detail AND HOW WELL THE MEASUREMENTS FIT WITHIN THEMSELVES (PRECISION)

Review the resulting position adjustment (residuals) under the Adjusted Grid/Geodetic Coordinates option, THIS REPORT IS THE MOST INDICATIVE OF THE SUCCESS OR FAILURE OF THE SURVEY AS IT SHOWS REPEATIBILITY OF THE POSITION AT THE SIGMA VALUE SELECTED


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The Adjusted GPS Observations portion of the report displays the required adjustment to each measured component, listing the Standardized Residual in descending order (worst case down)

The Occupation Spreadsheet allows editing of the setup details if necessary. In the network shown, Point 2 is suspect as it was common amongst the top 4 Adjusted GPS Observations and the error was primarily in the vertical. Reviewing the Occupation Spreadsheet shows the original antenna measurement at Point 2 to be to the “Bottom of the Antenna mount”, it should have been to the Bottom of Notch.

If blunders are found, antenna heights for example, and edited in the Occupation Spreadsheet the processing for the effected baselines will be automatically cleared and they must be re-processed.

Search out bad baselines, setups, repair/disable and readjust until the Network Reference

Factor approaches 1.0 and all other statistical indicators are nominal.

Check any other horizontal “control” positions against the published values under the Control Coordinate Comparision in the Network Adjustment Report:


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Once all known blunders are corrected, using the Scalar will direct the software to iterate, seeking 1 for the Reference Factor.

Weighting/Scalar - This option is used to balance the estimated errors (apriori) with the actual errors (aposterori) by scaling the estimated error parameters. Under Weighting in the Adjust Network box, click the asterisk button between the Ref. Factor and Scalar boxes. The two values will be equal. Re-adjust the network, the Reference Factor should now be 1.00 and the Chi Square test passed.

Review the Network Adjustment Report to insure all adjustments are within the Project tolerances. After all the statistical parameters are deemed acceptable, open the Network Adjustment Report, select File and use the Save As option to create a permanent copy of the report.


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FULLY CONSTRAINED HORIZONTAL ADJUSTMENT

The second adjustment tests the already proven measurements against the chosen horizontal control without the constraint of any vertical influence (since vertical errors can appear as horizontal problems in the true 3D world, this phase can be very helpful diagnosing blunders).

Set ALL horizontal control – under ADJUST/Points set the values and Fixed status for the horizontal control. Note that individual control points may be assigned specific weighting by using the Fixed Weighting icon:

ADJUST and iterate to PASS or higher - (this will be a fully constrained HORIZONTAL

adjustment, testing the network against the selected HORIZONTAL control ONLY)

Again use the REPORTS/Network Adjustment Report to determine the statistical quality of the network.


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As in the Minimally Constrained Adjustment, isolate and disable any problem vectors using either the Vectors Spreadsheet or Project Explorer.

The Weighting/Scalar used earlier will be re-set to 1.00 anytime the constraints are modified, as a result re-establishing a new Scalar may be necessary to pass the Chi-Square test. If so, repeat the steps on page 85 before proceeding to the final adjustment.

After all the statistical parameters are deemed acceptable, open the Network Adjustment Report, select File and use the Save As option to create a permanent copy of the report.


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FULLY CONSTRAINED, FULLY COMBINED (HORIZONTAL /VERTICAL) – FINAL

ADJUSTMENT

The final adjustment confirms the vertical measurements along with the proven horizontal values.

Select the appropriate boxes for the final Fixed Coordinates to be held, and use the Weighting option (as above) to bring the network to statistical compliance.

As in the previous adjustments, review the Network Adjustment Report to insure all adjustments are within the Project tolerances. As in the previous adjustments, isolate and disable any problem vectors using either the Vectors Spreadsheet or Project Explorer. The Scalar used earlier will again be re-set to 1.00 as the vertical constraints were added, as a result re-establishing a new Scalar may be necessary to pass the Chi-Square test. If so, repeat the steps on page 85. After all the statistical parameters are deemed acceptable, open the Network Adjustment Report, select File and use the Save As option to create a


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permanent copy of the report (TBC only maintains the current and previous adjustment reports).

The final results should resemble the following:


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CONVENTIONAL TRAVERSE ADJUSTMENT

The alternative adjustment method (for optical data only) to the Least Squares adjustment described above is the Adjust Traverse option which allows the Compass/Bowditch or Transit routines. Initially, go to Project Settings and enter the appropriate adjustment parameters under Computations/Traverse:

Once the conventional data has been downloaded from the Controller, go to Survey/Adjust Traverse:

After providing a Traverse Name and executing the Create option the software will find the first (chronologically) optical station. Clicking on the + button will then highlight and list the next observations forward to the next Control stations (if there are intermittent Control stations as below, click the + button again to highlight all potential observations):


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Note that the beginning and ending Stations can be oriented by Point ID backsight/foresight or by Station Orientation (in the case of multiple backsight/foresight observations).

Once the Traverse has been highlighted select the appropriate adjustment parameters under the Settings section:

After the Adjustment Settings have been selected an overview can be viewed under

Preview Results:


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After the Settings have been selected, press the Apply button to perform the adjustment, once done the results can be viewed by clicking on the Network Adjustment Report icon ( ) at the top of the Adjust Network dialog box:

Once the Traverse has been accepted it can also be viewed in the Project Explorer (note that each adjusted point now has a Traverse Adjusted record):


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DATA REPORTS – there are several imbedded report formats as well as the ability to generate custom formats using the Job Report Generator (see page 106).

The Reports can be printed or exported to Excel, PDF, and Word formats


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In addition to the reports listed above the Spreadsheet views can be copied to a text editor or Excel by highlighting the desired records, right clicking the mouse and using the Windows copy/paste command:

Pasted in Excel:


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CREATE ALIGNMENT IN TBC/STAKEOUT IN ACCESS

In order to create a simple alignment (as opposed to a road or corridor) in TBC, go to Line and select the Create Alignment option. Note that an alignment can be created by selecting existing points in the database or by simply clicking a new position on the screen.

One the Create Alignment has been chosen a dialog box appears asking for an alignment name and a choice to “define individual segments” or to “inscribe curves at the PIs”. The “inscribe curves at the PIs” option may be simpler even though there may not be any curves in the alignment. Once the alignment is named and the Horizontal Geometry definition has been selected the bottom half of the screen changes to the data import form allowing the starting Station to be entered if other than 0+00.

At this point place the cursor over the Northing box and double click a point or position on the screen and the Northing/Easting coordinate boxes will fill. Note that the “Type” value has defaulted to “no curve”. If the alignment is strictly a series of tangents (a pipeline for example), continue double clicking on the Northing box to add individual elements.

If a curve is required select Arc (under Type) and enter the radius and after highlighting the Northing box double click the point or position for the center of the arc. Then select the next PI with a double click and the arc will be created.

If required a vertical alignment may also be created by selecting the Vertical tab on the right side of the alignment and clicking on the Create Vertical Alignment tab:


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Once the alignment has been created the stationing can be labeled using the Corridor/Create Horizontal Alignment Label option.

For example, the above labels are created by the following settings (found either under Corridor/Create Horizontal Alignment Label or under Project/Project Settings/Abbreviations/Alignment Labels which can be saved in a Template):


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Additionally a report can be generated under Reports/More Reports/Alignment Geometry Report.

To export the Alignment to Access, highlight the alignment and open the Device Pane (it should automatically open when the controller is connected to the computer) and select the target folder on the controller, then select the yellow box with the up arrow. Choose the “RXL road exporter from surface” option (even though there may not be a surface in the TBC database). Then complete the following fields:

A “Road Name” is required – HOWEVER THIS WILL NOT BE THE ALIGNMENT

NAME IN THE CONTROLLER

In the “Horizontal Alignment” field choose the appropriate alignment - HOWEVER

THIS ALSO WILL NOT BE THE ALIGNMENT NAME IN THE CONTROLLER

Using the right hand scroll bar scroll down to the “File Name (Trimble Access)” field

and use the default or rename the alignment if necessary - THIS WILL BE THE

ALIGNMENT NAME IN THE CONTROLLER


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Then execute the “Export” option and the alignment will be transferred to the controller.

To view the alignment in the controller, open the appropriate Job, go to Map and select the up arrow near the lower right corner of the screen and select Layers. Click on the alignment and a check mark will appear on the right side of the screen resulting in the ability to view the alignment (under the up arrow/Options the station values can be displayed as well as the line work). Note that if the alignment is “picked” from the screen for stakeout the begin station will revert to 0+00

REGARDLESS OF THE VALUE USED WHEN CREATING THE ALIGNMENT IN TBC.

To stakeout the alignment and/or create offsets, go to Stakeout on the main menu, choose Alignments and use the arrows to highlight the appropriate alignment. At this point an offset can be created using that option at the bottom of the screen. NOTE that the PI offsets in Alignments (as opposed to Roads) create the true bisector at the PI whereas the Road offset is perpendicular. If only the offset nodes are required do NOT store the offset alignment but rather check the “Store Points at Nodes” box.


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Press Next to stakeout the alignment. Note as well that by going back to the main menu and selecting Stakeout/Points both staking options (Alignments and Points) are open simultaneously. Once both are open switching between the two is a matter of clicking on the

Trimble icon on the upper right corner and selecting the appropriate option (the equivalent of Alt/Tab in the Windows world)

NOTE: The RXL file can be treated as a Road or Alignment in Access and in fact editing the RXL is only possible under Roads/Define.

Example Reports:


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The Point Derivation report summerizes the various position sources and their relative relationships.

The standard Point List details positions as well as geodetic data:


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EXPORTING – TBC has several different default export formats for a variety of third party softwares as well as the ability to create custom configurations.


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Custom Export Format Editor (under the File pulldown)

The first page of the Export Format Editor allows the description, whether or not to include a header, record types, delimiters and default file extensions:


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After pressing Next, the following categories and fields are available for export:


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Note that when linear field are selected, different units may be specified for each field. If the

default <Display> is selected the exported fields will be in whatever units are set in the Project, if specific units are selected the exported fields will be in those units REGARDLESS of the Project settings.


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EXPORTING TBC/ACCESS DATA USING STYLE SHEETS

In addition to the Export routines and the ability to cut/paste, TBC data can also be formatted and exported using “Trimble Style Sheets”. The Style Sheets are xml formats that can be created/modified by the user and many are listed on the Trimble website at http://www.trimble.com/support_trl.asp?pt=TrimbleSurveyControllerfortheTSCe&Nav=Collection-32914. This is a 2 step process that requires the selected TBC data to be first exported using the Trimble Field Software Exporter (jobXML) listed under Export/Survey.

1. Select the appropriate data set, go to Export/Survey and select Trimble Field Software Exporter format. Verify the path/file name, and Settings (Units and output system format – grid or geodetic coordinates, there is a Grid and Global option that will work with a multitude of Style Sheets). Note that some xsl formats such as GPX require the lat/longs be Global). Click Export.

2. Go to Reports/Job Report Generator and complete the following: select the just created

jobXML file, select the desired Style Sheet format, provide the Save As file name and click OK. If the “View Output File” box is checked the created file will be automatically displayed.

The same xsl Style Sheets can be uploaded to the Survey Controller/Access. Once the Style Sheets are sent to the controller, go to Jobs in Access and Files in Survey Controller, select Import/Export then select Export Custom Format Files and fill in the prompted fields. The resultant file can then be downloaded using ActiveSync/Mobile Device Center.

In addition to the Export routines and the ability to cut/paste, TBC data can also be formatted and exported using “Trimble Style Sheets”. The Style Sheets are xml formats that can be created/modified by the user and many are listed on the Trimble website at http://www.trimble.com/support_trl.asp?pt=TrimbleSurveyControllerfortheTSCe&Nav=Collection-32914. This is a 2 step process that requires the selected TBC data to be first exported using the Trimble Field Software Exporter (jobXML) listed under Export/Survey.

3. Select the appropriate data set, go to Export/Survey and select Trimble Field Software Exporter format. Verify the path/file name, and Settings (Units and output system format – grid or geodetic coordinates, there is a Grid and Global option that will work with a multitude of Style Sheets). Note that some xsl formats such as GPX require the lat/longs be Global). Click Export.

4. Go to Reports/Job Report Generator and complete the following: select the just created jobXML file, select the desired Style Sheet format, provide the Save As file name and click OK. If the “View Output File” box is checked the created file will be automatically displayed.

The same xsl Style Sheets can be uploaded to the Survey Controller/Access. Once the Style Sheets are sent to the controller, go to Jobs in Access and select Import/Export then select Export Custom Format Files and fill in the prompted fields. The resultant file can then be downloaded using ActiveSync/Mobile Device Center.

http://www.trimble.com/support_trl.asp?pt=TrimbleSurveyControllerfortheTSCe&Nav=Collection-32914





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GETTING STARTED w RTK

The following section outlines the basic components and procedures to begin an RTK survey using the ACCESS TSC2 data collector. A detailed explanation of each option in the ACCESS controller and the download process follows in the Menu Details section beginning on page 153.

RTK SURVEY SETUP CONSIDERATIONS

& ACCESS CONVENTIONS

IN ORDER TO CONDUCT RTK SURVEYS SMOOTHLY, ACCURATELY, AND AS ERROR FREE AS POSSIBLE, IT IS IMPERATIVE THAT THE GOALS AND SPECIFICATIONS OF THE SURVEY BE WELL DEFINED AND UNDERSTOOD BEFORE ANY FIELD WORK IS CONDUCTED. KEEP IN MIND THAT NO MATTER WHAT FORMAT OR COORDINATE SYSTEM IS DISPLAYED ON THE SCREEN OF THE ACCESS CONTROLLER, THE SYSTEM IS ACTUALLY MEASURING LAT/LONG & HEIGHT RELATIVE TO THE WGS84 ELLIPSOID WHICH IS STORED AS A VECTOR FROM THE BASE STATION. IT IS ONLY THROUGH THE PROJECTION AND TRANSFORMATION PARAMETERS (CALIBRATION) THAT LOCAL COORDINATES, (EITHER LAT/LONG & HEIGHT OR NORTHING/EASTING & ELEVATION) ARE COMPUTED AND DISPLAYED. OBVIOUSLY THE ROUTINES AND TECHNIQUES USED TO ACHIEVE THIS TRANSFORMATION MUST BE DONE CAREFULLY AND WITH FULL UNDERSTANDING OF THE RAMIFICATIONS.

Before stepping through the ACCESS options and survey routines, following is an outline regarding the hardware and interface of the ACCESS unit itself.

POWER MANAGEMENT IN THE ACCESS

Power Source: The ACCESS is powered by a Lithium-ion battery when in a stand-alone mode. When the battery does run low, a low controller battery message is displayed along with an audible beep. Should the voltage level drop too low, the message controller battery is dead will be

shown and the ACCESS will automatically shut off.

SINCE THE MEMORY ABOARD THE ACCESS (WHETHER INTERNAL OR FLASH CARD) IS FLASH MEMORY, NO POWER IS REQUIRED TO MAINTAIN THE DATA, AND THEREFORE BACKUP BATTERIES ARE NOT NECESSARY.

Forced Power Down: If for any reason the ACCESS controller becomes "locked up" and will not respond to the keyboard, including the I/O (On/Off) key, the user may recover by pressing down and

holding the I/O key for a period of approximately 5 seconds. This is the equivalent of a “warm boot” .

Cold Boot: Perform a hard reset only if a soft reset fails to resolve an issue. After a hard reset, the operating system is reloaded into RAM from the Flash memory. Some software programs may also store shortcuts or database information in RAM; this is erased during a hard reset. When you use a TSC2 controller, data is stored on [\Built-in Storage], and is retained when you perform a hard reset. Registry settings and shortcuts are not retained.


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To hard reset the controller, hold down the CTLR key and the Power key. After about five seconds, a countdown timer appears, indicating that the controller will reset. Continue to hold down the CTLR key and Power key for a further five seconds, then release them. The controller briefly displays the boot screen and then resets to the default Microsoft Windows desktop view.

Removing the battery on a TSC2 controller causes a hard reset of the controller. Always perform a backup before you remove the battery.

When the TSC2 controller is hard reset, the operating system recognizes that a backup had been done, and prompts you to restore. This action is recommended. If you accept the restore, once the restore is completed, the controller soft resets and is ready for use. If you do not accept the restore, then some applications and shortcuts may not operate correctly.

ACCESS DATA FORMATS

All data contained within the ACCESS controller can be displayed using the Jobs/Review current job option. Upon entering the file review, the screen and cursor default to the last current record in the file. Depending on the status of the GPS calibration (projection and datum parameters, discussed further in this guide), the positional data may be viewed in the following four different formats by selecting the Options softkey after highlighting a particular point

WGS84 - displays the native GPS positions in latitude, longitude, and ellipsoid height relative to the WGS84 ellipsoid.

Local - also displays positions in latitude, longitude, and ellipsoid height in local terms which may be different from the WGS84.

Grid - displays positions in local Northing, Easting, and Elevation in terms of the specified datum and projection. Note that these values may be at ellipsoid “grid” OR at “ground”.

ECEF –Earth Centered, Earth Fixed Cartesian coordinates

NOTE THAT ALL VERTICAL VALUES EXPRESSED AS “HEIGHTS” ARE RELATIVE TO THE ELLIPSOID, ALL VERTICAL VALUES EXPRESSED AS “ELEVATION” ARE RELATIVE TO THE LOCAL USER DEFINED VERTICAL DATUM!!!!

REMEMBER TOO THAT THE SYSTEM ONLY MEASURES LATITUDE, LONGITUDE, HEIGHTS OR HORIZONTAL/VERTICAL ANGLE/DISTANCES (USING CONVENTIONAL EQUIPMENT), ALL OF WHICH MUST APPROPRIATELY ORIENTED FOR THE MEASUREMENTS TO TAKE PLACE AND THEN PROPERLY PROJECTED/COORDINATED TO THE PROJECT SYSTEM.


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BASIC ACCESS RTK SETTINGS

The ACCESS SETTINGS menu parameters control how the hardware and software basically behave (fine adjustments to some of these settings can also be made during the survey as discussed later). The SETTINGS menu has the following sub menus: Survey Styles, Templates, Connect (for Internet Setup, GNSS Contacts, Auto Connect, Radio Settings & Bluetooth), Feature Libraries and Language. This sections deals with the basic settings necessary to begin an RTK survey. More information about the Settings menu can be found in the Menu Details section on page 157. Before beginning any survey, the parameters available in these menus must be set appropriately. Once set the various options remain in effect unless the system is cold booted.

Survey Styles- THE STYLES DICTATE HOW THE DATA COLLECTOR AND INSTRUMENT

BEHAVE DURING THE COURSE OF THE SURVEY. ONLY ONE STYLE IS IN USE AT ANY

GIVEN TIME, HOWEVER MANY STYLES CAN BE USED IN A PARTICULAR JOB WHICH

ALLOWS BOTH RTK, RTK & INFILL WITH POST PROCESSING WHEN THE RADIO IS

DOWN AS WELL AS CONVENTIONAL “INFILL” WHEN GPS CONDITIONS ARE ADVERSE.

Default Styles are: FastStatic; PPK, RTK, RTK & Infill, RTK & Logging and VX & S Series, and IS Rover, although there may be user defined GPS styles in additional to the configuration for total.

RTK is real time kinematic which allows survey grade data collection, stakeout, and complete transformations – ALWAYS requires radio contact between base and rover(s) – requires initialization, however RTK & Infill offers all of the RTK options plus the option of post processing topo data collection when radio conditions are sporadic. Since the Base receiver is always storing raw data in the RTK & Infill style that data can also be sent to OPUS for accurate positioning.


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For the purposes of an RTK/Infill survey the style would be setup as follows:

Rover options - NOTE that any RTK data is hard wired to log at 1 second intervals.

Station Index – provides use of multiple base stations all broadcasting the same frequency. This option is limited to specific receivers (4000, one 4400 at the Base, 4700, 4800, 5700, and 5800/R Series). If a value is specified here (0-31), the Rover will respond only to that particular Base station. There is a softkey, Any to cover all possibilities.

WAAS – the 4700, 5700, and 5800/R Series receivers are all capable receiving corrections from the WAAS satellites and produce differentially corrected code phase positions.


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The Logging Device, Logging Interval, Auto File Names and Logging File Name are all devoted to the Rover Infill data. This data is ONLY collected when the Rover operator starts the PP Infill option once the survey has begun, for example when the radio or other Base connection fails. Normally, this raw data would be stored in the Controller at 1 second logging rates in a file of the user’s choice. The Elevation mask is normally 10 and the PDOP is 6. The Antenna type and Measurement to options should be carefully selected with the Antenna height left blank (to insure a actual field value instead of a default).

Check the Glonass option if the receiver has that option, as of October 1, 2011 Glonass offers approximately 6 more constant SVs during the typical observation day in the US.

Rover radio - sets the communication type (radio, cell phone/modem etc) and communication method. Using the Connect softkey allows the radio frequency to be changed in the field

Base options - sets Survey type, the Logging device, and the and Logging interval for post processing and/or OPUS submittal, (if post processing – NOTE that any normal RTK data collection is hard wired to log at 1 second intervals); correction record type; elevation mask; PDOP mask; and antenna type.


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Station Index – provides use of multiple base stations all broadcasting the same frequency. This option is limited to specific receivers (4000, one 4400 at the base, 4700, 4800, 5700, and 5800/R Series). The value specified here will be broadcast along with the differential correction data.

Typically the raw data would be stored in the Receiver in an automatically named file as follows: first 4 characters are the last 4 digits of the Receiver serial number, the next 3 characters are the Julian Day of the observations, and the last character is the session of the day beginning with 0 – for example 0789 (last 4 digits of the serial number) 064 (the 64th day of the year) 2 (the third session of the day) would be file 07890642.DAT or 07890642.T01. The DAT files are US SV data only, the T01 and T02 files are US and Russian SV data files.

As with the Rover options the Antenna type and Measurement to options should be carefully selected with the Antenna height left blank (to insure a actual field value instead of a default).

The final Base options screen allows use of the Glonass and other systems.

Base radio - sets the radio type (Trimble, Pacific Crest, etc.); controller/radio port; receiver/radio port (4700/4800 receivers with internal radios use port 4, 4700/4800 receivers using external radios use port 3, 5800/R Series receivers use port 1 if cabled – all other receivers use port 2 for the radio connection); baud rate and parity settings. Note that the newer R8 receivers have internal ½ watt broadcast radios for relatively small surveys.


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Topo point - sets the auto point number step size; quality control options (QC1/QC2/QC3); auto end point option; occupation time; number of measurements; and horizontal/vertical precisions

Observed control point - sets the auto point number step size; quality control (QC1/QC2/QC3); number of RTK measurements and horizontal/vertical precisions; and postprocess times dependent on SV availability

Rapid point - sets quality control (QC1/QC2/QC3) and horizontal/vertical precision for single measurement points


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Note that QC2 and QC3 are only beneficial if the vectors are to be incorporated in a least squares network adjustment.

Continuous points - sets horizontal/vertical precision for automated data collection (based on time and/or distance settings discussed later)

Stakeout - sets storage parameters for point names (design/auto); storage of delta values between design and actual; display parameters for grid deltas differences for guidance; and cut/fill to DTM models (see page 152).

Site Calibration - sets the calibration scale to 1.0/calculated; observation type, and maximum scales/residuals allowed

Duplicate point tolerance - sets distance tolerance to determine duplicate points

Laser rangefinder – allows use of a laser concurrently with the GPS receivers

Echo Sounder – allows use of an echo sounder concurrently with the GPS receivers

CONNECT/AUTO CONNECT AND BLUETOOTH – preset the connection parameters for GPS receivers, total stations, lasers, echo sounders and ASCII data transfer. Note that a specific receiver can be designated as a Base or Rover for automatic connection under Instrument/GNSS Functions.


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To establish Bluetooth connections, press Bluetooth/Config. Check the Turn on Bluetooth and Make device discoverable boxes and press Devices.

Tapping New Partnership or pressing Enter will start the Bluetooth search for any devices with 10 meters. Select the appropriate device and press OK, then Accept (note Trimble receivers and total stations do NOT need a passkey).

After the Bluetooth connections have be established, the Instrument Menu can be used to automate the connection to the Base, begin the survey, then connect to the Rover and begin the data capture/stakeout routines. As the devices are connected multiple options become automatically available


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BEGINNING A SURVEY

Surveying successfully with RTK is dependent on two underlying processes: initializing the survey in order to make GPS observations; and calibrating the survey in order to transform the GPS measurements into meaningful values (not necessarily in that order since it is possible to calibrate a job in TBC before beginning the actual RTK field survey as well as upload coordinates for stakeout before the any GPS measurements are made or the project is calibrated). The sequence in which these two phases are implemented is dependent on the survey specifications and required control.

The following outlines summarize the sequence and methodology necessary to begin and conduct two typical types of RTK surveys. While both types are identical in terms of GPS functionality (satellite use, integer ambiguity resolution, etc.), they are markedly different in terms of the coordinate system required by the project and its relationship to the GPS system. These differences are found primarily in the GPS calibration procedure and coordinate system setup and procedures.

NOTE THAT ALL SITE CALIBRATIONS MAY BE RECOMPUTED AND REFINED AT A LATER DATE. ALSO NOTE THAT THE CALIBRATION IS NOT INTENDED TO SHIFT THE RESULTING COORDINATES BY MORE THAT ABOUT 200’.

TYPE 1 (AUTONOMOUS, LOCAL COORDINATES):

PROJECTS THAT ONLY REQUIRE ASSUMED LOCAL COORDINATES (AUTONOMOUS WGS84 LLH) AND USER DEFINED NEE – THE GPS CALIBRATION CAN BE CONDUCTED COMPLETELY IN THE FIELD. THIS INCLUDES PROJECTS WHERE AN EXISTING NEE COORDINATE SYSTEM IS REQUIRED AND ITS PRECISE RELATIONSHIP (THROUGHOUT THE EXISTING SYSTEM) TO GPS OBSERVATIONS IS NOT KNOWN, AS WELL AS STAKEOUT JOBS WHERE ONLY THE NEE VALUES ARE KNOWN BEFORE BEGINNING THE FIELD WORK.

This type of survey, requiring only assumed local coordinates in all three values is very useful and productive for localized topo projects. HOWEVER, it is also the least controlled and requires careful attention to the calibration sequence (as the survey is radial, independent closure evaluation and adjustment of the GPS measurements is not possible). Basically, the ACCESS controller computes the required calibration parameters between the current AUTONOMOUS based WGS84 GPS positions and user entered coordinates. These values define the relationship between the lat/long/height native to GPS, and the local coordinate system and local vertical datum (the ACCESS controller also allows use of user specified geoid models to refine the elevations). The ACCESS Job database maybe re-calibrated as often as necessary and the individual points used in the calibration may be used for horizontal or vertical control or both (1D, 2D, and 3D points). If the Job is calibrated multiple times, ONLY the last calibration is used to

define positions. These transformation parameters are created through the SURVEY MENU/Site Calibration.

NOTE THAT A CALIBRATION IS ONLY REQUIRED IN THE FIELD IF NEE VALUES ARE

NECESSARY, OTHERWISE POINTS MAY BE COLLECTED WITHOUT CALIBRATING.

The ACCESS controller organizes the data in Jobs which can be created, opened, reviewed, edited and copied under the Jobs Menu. When a Job is created it will contain the settings of either of the following: Last Job Used, Default, or user defined Templates. For example, the


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Template may be preset for a State Plane Coordinate System using a specific Geoid Model, etc. Templates can be created, imported, edited, renamed and deleted under Settings/Templates

Under General Survey (or Roads)/Jobs create a New Job. In this case, use the Default Template and select No Projection/No Datum under the Coordinate System option (“No

Datum” in this case means no datum transformation from the WGS84 ellipsoid used natively by the GPS system).

Note that user defined Folders can be selected/created using the Select Folder icon right of the Job Name


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No Projection means no projection was selected, HOWEVER it also means a default choice between two different types of coordinate systems which will be used if/when a Site Calibration takes place. When No projection/No Datum is initially selected, a Site Calibration sub screen appears offering the following choices:

Coordinates: this is a toggle, switching between Ground and Grid.

If Ground is chosen, a User Defined Transverse Mercator projection will be created after a GPS Site Calibration is performed. The project height (below) provides the projection scale factor (meaning that the coordinate “grid” is located at a common “ground” elevation, meaning further that now a simple inverse of the point coordinates will closely match distances computed by conventional means). The projection scale factor will be other than 1.0000 (NOT TO BE CONFUSED WITH THE SITE CALIBRATION HORIZONTAL SCALE FACTOR). The GPS Site Calibration provides the desired relationship (origin of the projection) between the user defined coordinates and the lat/long of the project.

Project height: The value here is required and in combination with the earth radius at the Job’s WGS84 lat/long, computes the scale factor for the Transverse Mercator Projection. This value is also used to compute the lat/long for stakeout points that do not have elevations of their own.

If Grid is chosen, the GPS measurements will be projected to a plane AT THE ELLIPSOID. The projection scale factor will be 1.0000 (NOT BE CONFUSED WITH THE SITE CALIBRATION HORIZONTAL SCALE FACTOR).


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No matter the coordinate system type or whether the system is “grid” or “ground”, a Project height is required:

Use Geoid Model: offers use of a loaded geoid model to enhance GPS derived elevations. This should be applied in all cases where the vertical component is going to be used. (geoid models are available in the TBC software and easily subdivided to a reasonable size to upload to the ACCESS under the Device Pane.)

Established Projection and Datum types are also available, but require specific site information from the user and can be done more reliably using the procedures outlined later for survey TYPE 2 (see on page 128).

ALSO NOTE THAT NO MATTER WHAT COORDINATE SYSTEM/PROJECTION IS

CHOSEN OR METHOD OF CALIBRATION USED, THE SYSTEM WILL STAKEOUT

APPROPRIATE GROUND POSITIONS – GIVEN THE COORDINATES PROVIDED!!!!!!!

If the project involves stakeout procedures with northing/easting/elevation design data available, the data can be keyed in on the Access Controller or exported and Linked to a Job in Access, or finally exported from TBC. To export an ascii point file use Active Sync or Mobile Device Center when the Controller is connected.

On the Access Controller, create a Job and under Properties use the Linked Files option (see above page 32) to allow the Job to access the point coordinates. At this stage proceed to Begin Field Work on page 124).

Export data through TBC

Open TBC and under the FILE pulldown menu, select New Project using the appropriate template (the TBC program has stock templates for metric and US Survey feet, both of which use a local Transverse Mercator projection – BOTH EXISTING PUBLISHED AND USER DEFINED COORDINATE SYSTEMS CAN ALSO BE SELECTED AND STORED AS TEMPLATES). If Default Transverse Mercator is chosen, and only northing/easting values are imported, the coordinate system is not complete as the original latitude/central meridian and scale factor are missing (this will be completed when a field Site Calibration occurs).


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If northing/easting coordinates representing ground values are required, the Project Settings/Local Site Settings options must also and independently be set: Project Location specifies the point from which the computations originate to project the “grid”

values to “ground”; Compute ground scale factor allows a scale (computed from the project location or user defined) to be applied to the “grid” values in order to project to “ground” values; and Coordinate Display/Northing Easting offsets which allows additional offsetting of the “grid” vs. “ground” values. The ground scale factor will be other than 1.0000 (NOT TO BE CONFUSED WITH THE SITE CALIBRATION HORIZONTAL SCALE FACTOR.) NOTE THAT THE RESULTING BEARINGS WILL BE BASED ON THE ORIGINAL CENTRAL MERIDIAN FOR THE PROJECTION, NOT THE LOCAL SITE LOCATION.

A Project Height will also be required to open the Job in Access (this may be used to compute the above mentioned “ground scale factor” as well as to compute any grid points that do NOT have design elevations).


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IF THE PROJECTION/COORDINATE SYSTEM PARAMETERS BETWEEN LLH AND NEE ARE KNOWN, SEE THE TYPE 2 SURVEY OUTLINED LATER IN THIS DOCUMENT (on page 128).

IMPORT/EXPORT

Once the Project has been created, use the FILE/Import routine or the Import icon shortcut on the Toolbar to include the design data in the Project. Once the Import function has been activated, select the appropriate directory path and the file will be listed. Highlight the desired file and right click to select the file type (including control quality, etc).

Using the FILE/Export routine or the Export icon shortcut on the Toolbar, either create a Data collector file (Job) or export directly to the ACCESS controller or PC card using the Data/Device Pane/Survey Device or the Device icon (this last option formats the data and sends it to the device in one operation WITHOUT CREATING A FILE ON THE COMPUTER). Controller Versions 10.80+ requires Microsoft ActiveSync/MDC for the connection to the computer. ActiveSync/MDC will automatically open on the computer and asks if a partnership should be established, answer No. Once ActiveSync/MDC has connected, the Device Pane is automatically displayed and the ACCESS is now slaved to the computer.


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To load Feature Codes, antenna configuration files, geoid models, and datum transformations (ie. Nadcon for NAD27 jobs), use the Tasks option under the Direct Connection feature.


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After a Job has been created/imported and selected, the operator must complete the following steps to begin an RTK survey:

Select Measure from the General Survey menu (or alternatively begin the survey using the Instrument Menu as per page 30). Upon entering this menu the system automatically displays a list of available Survey Styles. Select the appropriate Style as listed below:

If the Base receiver has not been previously connected, tap the flashing instrument icon on the upper right corner to establish the Bluetooth connection:

From the Start Base Receiver option, begin the survey by entering the Base station name (both alpha and numeric characters are allowed), Code, and Antenna height (note that the measurement type is available by pressing a left/right arrow key when the cursor is in the antenna height field which activates the Antenna softkey menu selection).

ERRONEOUS ANTENNA MEASUREMENT TYPES MAY PRODUCE VERTICAL ERRORS

OF 15+ CENTIMETERS!!!).

Since there are not as yet any known GPS positions, the system prompt that the point does not exist when the Point Name is entered. When this occurs, use the right arrow on the Point Name field, click Key In and then use the Here key to obtain an autonomous LLH (KEEP IN MIND THAT THE SURVEY WILL BE PRECISE WITHIN ITSELF, BUT INACCURATE IN THE WORLD).


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After the Base has been started, disconnect the ACCESS controller from the base (except in the case of a post processed survey where the raw data is being stored on a data logger

- not the usual procedure) and connect to the Rover. The system is now ready for

initialization, required for all survey grade kinematic surveys whether real time or post processed.

To begin the Rover operations and collect the necessary points for the GPS Site Calibration, follow the steps outlined under the Start Survey section on page 135.

ACCESS GPS SITE CALIBRATION

If northing/easting, and elevation are required in the field, the Job must be calibrated to transform the GPS measurements to the appropriate coordinate system. This process may be accomplished as soon as the Job contains at least one GPS point whose desired northing/easting and elevation are known (for example, the Job may be calibrated as soon as the Base is started if NEE values for that position are available).

If the Job was created in TBC and loaded with design points for stakeout, at least two (four if the vertical is important) corresponding ground positions must have been observed with GPS in order to completely and precisely calibrate the Job (accounting for rotation, scale, etc.). HOWEVER, the calibration process can be incremental, that is, additional points may be added to the calibration as they become available.

To begin this process, select the SURVEY/Site Calibration option. The screen will display a message stating No points and two softkeys will appear at the bottom of the screen, Add and Options.


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Options - allows the operator to force the horizontal scale to 1 (advisable in most cases to preserve the precision of the GPS), or accept the computed scale in order to scale the GPS measurements to fit the local monumentation (the results of the calibration will also state the computed rotation which can also be accepted or overwritten with operator input) as well as allowing minimum/maximum settings for the horizontal/vertical residuals (the calibration is a least squares best fit algorithm) as well as the minimum/maximum acceptable horizontal scale if using Auto Calibrate.

Add - accepts point names for the Grid point (NEE), the GPS point (LLH) and Use (that point’s particular function in the calibration, horizontal only, vertical only, or horizontal & vertical). Using the right arrow on the point name field accesses a List function for point already in the database.

Use the Add option to compile the list of points to be used in the calibration (remember that the calibration may be performed as often as necessary so testing, editing, and confirming the results are possible – incremental calibration may well be necessary for projects such as Section breakdowns where corner recovery is conducted by navigating with the SURVEY/Stakeout/Points option).

As points are added to the list, the system automatically calibrates and displays the H.Resid (horizontal residual), the V.Resid (vertical residual), and the point Use on a point by point basis (obviously, the horizontal residuals will not appear until at least two points are used in the calibration, similarly at least four vertical points must be included in order to compute the vertical residuals).


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Results - displays the following calibration statistics: Number of points in the calibration, Horizontal scale and rotation, maximum Horizontal residual, incremental adjustment in the north and east, overall elevation shift, and the maximum Vertical residual and inclined plane parameters (note the Horizontal scale and rotation may be overwritten by the user).

NOTE: In general, the slopes of the inclined plane generated by the vertical

calibration should not exceed 100ppm. These proportional values should be tested

against the Job dimensions to determine the severity of the relative tilt.

After adding all the requisite points, execute the Apply option to calibrate the Job database. At this stage, any display of the database using FILES/Review current Job will allow the operator to view either LLH or NEE values. NOTE THAT THE NORTHING/EASTING VALUES ARE A PRODUCT OF THE COORDINATE SYSTEM TYPE SELECTED WHEN THE JOB WAS CREATED.

In addition, once the calibration is performed, the operator can view a map of the Job, complete with zoom, pan, and filter display.

The Job is now setup for all data capture options (page 134) and stakeout functions (page 142).


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TYPE 2 (GLOBALLY ACCURATE, ANY COORDINATE SYSTEM):

PROJECTS THAT REQUIRE LOCAL COORDINATES (LLH and NEE) WHICH ARE USER DEFINED OR TRADITIONAL STATE PLANE SYSTEMS, BASED ON A PREVIOUS GPS CONTROL NETWORK, EMPLOYING FULL CONSIDERATION OF THE GEOIDAL SEPARATION - GPS CALIBRATION PERFORMED (AT LEAST INITIALLY) IN Trimble Business Center (TBC).

This type of survey is the most “repeatable” and should be used whenever ANY of the following conditions exist:

The project is of high order and the best possible precision is required.

The project is of such a scope as to warrant multiple base setups to cover the area involved (especially true with corridor type surveys such as transmission lines, canals, roads, etc.).

The project is long term and will be visited repeatedly (mining operations, large construction sites, etc.).

A GPS survey has been performed using Static or Fast Static methods to establish control points which have been translated from the native WGS84 lat/long/height to a traditional coordinate system such as State Plane.

ANY FUTURE THOUGHT OF INCORPORATING THE DATA INTO A GIS

Without question, the most reliable way to conduct this type of survey is to first employ GPS (and possibly some differential leveling) to establish control. In the case of State Plane surveys, this dictates observing at the very least two (THREE ARE HIGHLY RECOMMENDED) known State Plane monuments (or the OPUS equivalent) for the horizontal reference, and at least four (FOUR ARE REQUIRED, MORE ARE HIGHLY RECOMMENDED) monuments with published vertical values registered to the same datum (WATCH OUT FOR THIS VERTICAL CRITERIA - DIFFERENCES, DISPARITIES, AND DOWNRIGHT BLUNDERS ABOUND IN THE AREA OF VERTICAL MONUMENTATION).

The calibration procedure is the main area of difference between this type of survey and Type 1 discussed previously (page 117). In this case, at least the initial calibration is conducted in TBC, and the source data point values (LLH and corresponding “grid” values, either 2D or 3D) are usually obtained from a network adjustment or other reliable sources. In this example, the data is from ascii files.

Open TBC and under the FILE pulldown menu, select New Project using the appropriate template (the TBC program has stock templates for metric and US Survey feet, both of which use a local Transverse Mercator projection – BOTH EXISTING PUBLISHED AND USER DEFINED COORDINATE SYSTEMS CAN ALSO BE SELECTED AND STORED AS TEMPLATES). Under Project Settings click Coordinate System/Change to select the appropriate system. Once the coordinate system has been selected click next through the boxes for the geoid model.


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If the coordinates are meant to be “ground” values, select Project Settings/Local Site Settings to insure the appropriate scaling. Provide the position from which the grid will be scaled to ground and either provide the Ground Scale Factor or check the box for TBC to compute the scale.


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Import the GPS (Lat/Long/Height) data, BE SURE TO SELECT THE APPROPRIATE FORMAT OF LLH! ALSO BE SURE TO DISTINGUISH THE LLH POINT NAMES FROM THE NEE POINT IDs!

Next, import the planer data (2D or 3D), BE SURE TO SELECT THE APPROPRIATE FORMAT FOR NEE!


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TBC CALIBRATION

Select the SURVEY/Site Calibration option from the SURVEY pulldown menu and fix the desired calibration component settings (whether the calibration is Horizontal and/or Vertical. Normally, hold the Horizontal scale to 1.00. Proceed to the SURVEY/Site Calibration/Point List button. When selected, the point list will open a dialog box setup for selecting both the GPS and NEE control points. Using the mouse cursor, select the appropriate points for the calibration. After all the points have been selected, execute the Compute option.

The results are displayed as follows:


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The Site Calibration/computation summary section of the dialog box displays the Horizontal adjustment scale factor (not the same as the projection scale), the Maximum Slope of Inclined Plane, the Maximum horizontal residual, and the Maximum vertical residual. These values should all be within reason and the tolerance of the survey.

Using the Save as Site button allows the creation of an entry in the Coordinate System Manager/Site Zones which includes the formal projection (if any) as well as the calibration parameters for future Projects.

If the calibration results are acceptable the next stage is to create a data collector file for export. Go to the Device Pane/Export (the blue arrow) and use the Options button to select the Control points. Press OK and the points as well as the coordinate system and Site

Calibration parameters will be transferred to the Access as a Job in the highlighted folder..

IF A GEOID MODEL WAS USED IN THE GPS CALIBRATION, OR WILL BE USED IN THE

FIELD, BE SURE TO LOAD THE MODEL INTO THE ACCESS AT THIS POINT (NOTE THAT

THE EXPORT PROGRAM ALLOWS TRANSFERS OF SEVERAL DIFFERENT FILE TYPES,

INCLUDING GEOID, DTM, ANTENNA, AND FEATURE CODE FILES). THIS IS

ACCOMPLISHED BY SIMPLY CLICKING TASKS ON THE DEVICE PANE AND

SELECTING THE “UPLOAD GEOID (GGF) FILES” OPTION

IF THE PROJECT IS ONGOING, A “MASTER” JOB FILE INCLUDING THE CONTROL

POINTS SHOULD BE CREATED IN TBC AND UPLOADED TO THE ACCESS. ADDITIONAL FIELD WORK SHOULD BE DONE IN A NEW JOB, USING THE FILES/COPY FROM ANOTHER JOB OPTION (FROM THE “MASTER”) TO MAINTAIN A CONSISTENT COORDINATE SYSTEM (FOR EXAMPLE MULTIPLE ASPECTS OF THE SAME PROJECT, THIS ALSO ALLOWS SHARING DATA BETWEEN CONTROLLERS WITH THE USE OF THE USB PORT).


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Once the file is in the ACCESS proceed to the DATA COLLECTION and/or STAKEOUT sections that follow.


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DATA COLLECTION

After a Job has been imported/created the ACCESS operator must complete the following steps:

Select SURVEY from the main menu. Upon entering this menu the system automatically displays a list of available Survey Styles. Select the appropriate Style as listed below.

If the Base receiver has not been previously connected, tap the flashing instrument icon on the upper right corner to establish the Bluetooth connection:

From the SURVEY/Start Base Receiver option, begin the survey by entering the Base station name (both alpha and numeric characters are allowed), feature code, and antenna height (note that the measurement type is available by pressing a left/right arrow key when

the cursor is in the antenna height field with the Antenna option).


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After the Base has been started, a Base Started message will appear and the ACCESS Controller will automatically disconnect from the base (except in the case of a post processed survey where the raw data is being stored on a data logger - not the usual procedure) and connect to the rover.

To connect to the Rover, tap the flashing instrument icon on the upper right corner to establish the Bluetooth connection:

Select MEASURE/Start Survey to begin the rover operations. The system is now ready for initialization, required for all survey grade kinematic surveys whether real time or post processed.


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INITIALIZE

The steps required for this process are totally dependent on the equipment type and configuration. If the receivers are dual frequency AND at least 5 SVs are available, Trimble has developed an “On The Fly” (OTF) technique which allows the rover to initialize anywhere without

the requirement of knowing the X, Y, and Z values between the rover position and the base. Once the survey has been started, the system will automatically attempt to initialize using OTF. If the observation conditions are nominal, this should occur within a matter of a minute or so.

If the receivers employed are single frequency, or there are only 4 satellites available, the

Initialization must be carried out by observing a known GPS point (SURVEY/Initialization/Init/Known Point). The relationship of the Known Point to the Base must be known in GPS terms (WGS84 coordinates) to within 5 cm. The discrete steps needed for initialization are prompted by the ACCESS which reports success or

failure, as well as the horizontal and vertical differences between the expected and actual

X, Y, and Z values.

IN KEEPING WITH STANDARD SURVEY PRACTICE, IT IS ALWAYS A GOOD IDEA TO

CHECK INTO ANOTHER KNOWN POINT IF AT ALL POSSIBLE. AT THE VERY LEAST, A

CHECK SHOT SIMILAR TO RE-OBSERVING A BACKSIGHT SHOULD BE MADE AT

APPROPRIATE TIMES DURING THE SURVEY TO VERIFY THAT NO PROBLEMS HAVE

ARISEN (STATISTICALLY, 1 IN 10,000 INITIALIZATIONS WILL TEMPORARILY COMPUTE

ERRONEOUS INTEGER COUNTS). IF A KNOWN GPS POINT IS NOT AVAILABLE (AS IN

THIS TYPE OF SURVEY), A POINT SHOULD BE SURVEYED AND A RE-INITIALIZATION

SHOULD BE PERFORMED ON THAT POINT.

In both of the above cases, if satellite “lock” between the receivers and the satellites is broken (if fewer than 4 SVs have continuous data streams), it is necessary to re-initialize the survey as described above.

ANY POINTS SURVEYED FROM THIS POINT FORWARD WILL SERVE AS KNOWN POINTS IN TERMS OF INITIALIZING (AND PERHAPS CALIBRATING, SEE PAGE 125), AND AS SUCH WOULD REQUIRE ONLY 4 SVs AND ALSO SERVE AS CHECKS (ESPECIALLY IMPORTANT WITH OTF INITIALIZATIONS).

After the Initialization procedure has been performed, the system is ready to conduct the survey, either to collect data, or if a calibration has also been performed, stake out design points, or both.


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Observing point positions is simply a matter of pressing the Enter key while in “roving” mode and waiting until the system is satisfied that the prescribed tolerances have been met (assuming the auto end point is selected). Bear in mind that the observations are to the phase center of the antenna WHOSE RELATIONSHIP TO THE GROUND POINT IS ABSOLUTELY AND TOTALLY DEPENDENT ON CORRECT ANTENNA TYPE SELECTION, ANTENNA MEASUREMENT TYPE, ANTENNA STABILITY, AND “PLUMBNESS” OF THE ANTENNA STAFF. THE MOST COMMON ERRORS IN GPS ARE DUE TO INCORRECT ANTENNA DETAILS AND POINT IDENTIFICATION.

Data collection is controlled through the routines found under the SURVEY menu, specifically using the Measure points, Measure Codes, and Continuous topo. Each of these routines has its own sub menus and options as follows:

Measure points

When the Measure points option is selected, the screen displays fields for point name, the code, the point type, and the antenna height.

Note that the occupation time is being tracked as well as the horizontal and vertical precisions. Additionally on the right sidebar a stick figure indicates that an observation is taking place.

Point name - Defaults to the next available point number in the database but can be overwritten at any time. If the operator enters a point name that is already in use, the system notifies the user, continuing and storing the point prompts with following choices, Discard, Rename, Overwrite, Store as a check, or Store another


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(overwrite does not actually overwrite the previous point but reclassifies it, using the check option stores the point but as a “check” classification that will not override a higher quality such as keyed in positions when the position is used in inverses or other computations, store another provides the database with two vectors to the same point-these positions are meaned as per the TBC recompute rules – more on page 43.

Code - Defaults to the last code used. When a code list (uploaded from TBC) is activated, pressing a key will highlight the first code in the list that begins with that particular key character. Continuing to spell the code will position the cursor accordingly – once the appropriate code is highlighted, press enter to select the code from the list. Note that this action automatically places a space at the end of the code

in anticipation of more text. IF THE CODE HAS ATTRIBUTES THE “ATTRIB”

SOFTKEY APPEARS AFTER THE CODE HAS BEEN ENTERED.

Method - Toggles between topo point, kinematic control point, and rapid point (selections here are dependent on survey type). The point type dictates the observation parameters as set under the Survey Style routines, however, many of these parameters may be overwritten by using the Options softkey at the bottom of the screen.

Antenna height - Defaults to the previous value used. The antenna height field will not

accept a null value and prevents further action until a value is entered. ERRONEOUS

ANTENNA MEASUREMENT TYPES MAY PRODUCE VERTICAL ERRORS OF 15+

CENTIMETERS!!!

ALSO, UNIT CONVERSIONS CAN BE DONE WITHIN THE ANTENNA HT FIELD: FOR EXAMPLE, IF THE JOB IS CONFIGURED IN FEET, THE ANTENNA HEIGHT

MAY ENTERED IN METERS IF THE NUMERIC VALUE IS FOLLOWED BY “M” – THIS WILL CONVERT THE MEASUREMENT TO THE CURRENT JOB UNITS (2m will produce 6.562 US feet).

In addition to the above fields, the screen also displays an Options softkey, which allows observation parameter adjustments.

NOTE AFTER PRESSING THE MEASURE SOFTKEY (ALTERNATIVELY PRESS ENTER AT THIS STAGE), THE OBSERVATION WILL AUTOMATICALLY MEASURE AND STORE THE POINT IF THE AUTO END POINT OPTION IS SET TO YES. ADDITIONALLY NOTE THAT THE BOTTOM OF THE SCREEN CONSTANTLY DISPLAYS THE CURRENT PRECISION OF THE SYSTEM – BEFORE ACCEPTING ANY MEASUREMENT BE SURE THAT THE CURRENT VALUES COMPORT WITH THE REQUIREMENTS OF THE SURVEY.

Measure Codes – allows user defined Code groups and point measurement activated by Code selection. Note that the Feature Definition Manager in TBC allows creation of the

Measure Code Groups which will be uploaded to Access along with the Feature Library. In addition, the Measure Codes form can be configured for up to 25 code buttons as well as for Template Pickup (on road cross sections for example) using the Options button.


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CONTINUOUS TOPO - Depending on the survey type (real time or post processed), the continuous topo screen will display the setup parameters and allow specific values to be entered through the following fields:

Method - Either logs by Fixed Distance from the last point(s) or by specified Time Intervals. If the system is post processing mode only, the Fixed Distance interval is not available.

Antenna height - Defaults to the previous value used. The antenna height field will not accept a null value and prevents further action until a value is entered.

Horizontal distance - If the Fixed distance option was selected as the Type, this field sets the distance interval.

Time interval - If the Time interval option was selected as the Type, this field sets the time interval.

Offsets - If the Fixed distance option was selected as the Type, the operator can also select up to two offsets from the moving antenna position. This field sets the offset type; None, One, or Two. Once the offset type is chosen, Horizontal and Vertical offset fields are displayed in order to set the offset values.

In addition to the above fields, the screen also displays Measure and Options softkeys which initialize the continuous observations and allow observation parameter adjustments. If the ACCESS hardware has been configured to sound an audible beep, the sound will be heard at each measurement interval, whether distance or time.


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When the continuous topo is complete, press the End softkey to terminate the continuous storage.

IF LOGGING DATA IN EITHER POINT MEASURE MODE OR CONTINUOUS TOPO, USING THE Switch To KEY ALLOWS THE OPERATOR TO SHIFT TO THE OTHER MEASUREMENT MODE AND COLLECT DATA IN THAT MODE SIMULTANEOUSLY. A TYPICAL EXAMPLE WOULD BE OPERATING IN CONTINUOUS TO LOG A SIDEWALK AND CONCURRENTLY MEASURING FIRE HYDRANTS AND VALVES.

THE Switch To KEY ALSO ALLOWS “MULTITASKING” WITH A VARIETY OF OTHER USEFUL OPTIONS SUCH AS JOBS/CURRENT JOB MAP, AND JOBS/REVIEW CURRENT JOB.

QUALITY CONTROL RECORDS

Even though measured points have built in quality control set through the observation parameters (horizontal and vertical precision specifications), the quality control records QC1,

QC2, and QC3 are also available to document various position qualities as follows:

QC1 logs the minimum number of satellites used in the observation, the PDOP/HDOP/VDOP values, the total number of measurements, and the beginning and ending time of the observation. This record is required.

QC2 records the covariance matrix so the RTK vectors may be used in TBC network adjustments.

QC3 stores standard error and error ellipse values as well as unit variance.

PP Infill/Data Logging

If the current Survey Style is real time and includes either PP Infill or Data Logging, several options are available to both continue the survey when the radio link is interrupted and add strength to the survey with additional vectors to the radial real time points. NOTE HOWEVER THAT THESE TWO OPTIONS ARE ONLY IN EFFECT IF THE BASE RECEIVER WAS STARTED IN A PP INFILL OR DATA LOGGING MODE!

PP Infill mode configures the Base receiver to continually log raw measurement data at a user defined interval and allows the operator to selectively activate raw measurement storage at the Rover in the event of a prolonged disruption of the radio link.

When the radio link is lost, the screen will display the message radio link down (the radio icon usually displayed on the right menu bar will also disappear). After ascertaining that the radio interference is other than transient, the operator simply executes the Start/PP Infill option on the SURVEY menu to activate this option. Since the radio link carries vital information for both the initialization and differential correction, the system MUST be re-initialized at this stage. If a known point is available, occupy the point for at least 20 seconds in order for the post processor to initialize its computations. If known points are not available, occupy a new point for 8 minutes to collect the data necessary for post process initialization.

After the PP Infill has been initialized, continue the survey in the same fashion as the RTK described above. The only difference will be that the observations will now be dependent on the correlation between the PP logging interval and the user defined number of


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measurements as set Survey Style parameters (the number of measurements setting can be changed using the Options softkey at the bottom of the measurement screen).

If the radio connection returns, the message radio link up will appear on the screen as well as the radio icon on the right menu bar. At this time, execute the Stop/PP Infill option on the SURVEY menu and continue in the normal RTK mode.

Once the survey is completed, download both the ACCESS file and the Base data file into TBC and proceed to the Process GPS Baselines option.

Data Logging mode differs from PP Infill in the fact that raw measurement data at the Rover is ALWAYS stored and the Base radio MUST be received.

This option allows the use of more than one Base receiver(s) to generate another baseline vector(s) to the Rover unit and subsequently a mathematical closure for the observed point(s). For example, the operator is using RTK to stakeout positions that require a higher degree of confidence than a single radial vector would allow. By post processing the vector from a second Base, the RTK position can be confirmed. By combining both

the RTK and post processed vectors, a least squares adjustment can be performed using the TBC ADJUSTMENT option.


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STAKEOUT

In addition to the obvious advantage of being able to check and verify the precision and status of the system, RTK also allows the use GPS for staking out design points, lines, arcs, roads,

alignments, and design surfaces (terrain models). This option is only available in a real time

mode that requires the communication link. But it also means that stakeout can be performed very rapidly, without line of sight from the base instrument as required with a conventional total station, and at relatively long distances from the base station (the distance is practically limited only by the reach of the broadcast). Since virtually all design values are based on northing/easting Cartesian coordinates and local elevation datums, Stakeout also requires that the Job has been calibrated and or has a defined coordinate system. As discussed in an earlier section of this guide, the calibration can be performed either in the TBC software or in the field in the ACCESS.

Remember too, that design values can uploaded into the data logger BEFORE a calibration has taken place (see the discussion of the Type 1 survey previously), a very important feature for small jobs that do not require a previous control survey and as such do not yet have the GPS side of the calibration equation.

To implement the Stakeout routines, go to the General Survey/Stakeout routine and select the appropriate option as detailed below. These options allow the use of filters and point specifications so the setup for stakeout is very efficient and productive.

Stakeout/Points - When this option is accessed, the screen displays the message No items as well as the Add softkey.


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When the Add option is selected, a sub menu with the following options is displayed:

Select from list displays a list of all points in the current Job database with a check box on the left hand side of the screen (by default, no points are selected at this stage).

Once one or more points have been selected, Add, Delete, Del All, and Closest softkeys are displayed. The purpose of the first three softkeys is literal, the Closest softkey searches the selection list for the point closest to the current Rover position and proceeds to the actual stakeout operation (this option greatly reduces wasted time random wandering from point to point across the project). These softkeys also appear after any points are selected using the following selection options.

After the point selection has been completed, highlight the desired point for stakeout (or alternatively press the Closest softkey), press Enter, and the system will begin the stakeout process and display the stakeout screen graphics.


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The up arrow at the bottom of the screen accesses the Options available for the Stakeout procedures:

The stakeout screen is split vertically; the left side of the screen initially displays a graphic arrow indicating the direction necessary to travel to the selected point, the right side of the screen displays either polar directions (azimuth, horizontal distance and vertical distance), or rectangular directions (distance north, east, and vertical distance) depending on the setting for Display grid deltas field under the Stakeout/Options menu. The rectangular directions require a calibration. Once the rover is within approximately 3 meters of the point to be staked, the graphic arrow is replaced by a cross indicating the current Rover position superimposed over a “bull’s eye” target. When the cross matches the center of the bull’s

eye, the desired position has been achieved. NOTE THAT THE BOTTOM OF THE

SCREEN CONSTANTLY DISPLAYS THE CURRENT PRECISION OF THE SYSTEM –

BEFORE ACCEPTING ANY MEASUREMENT BE SURE THAT THE CURRENT VALUES

COMPORT WITH THE REQUIREMENTS OF THE SURVEY.

THE USER MAY TOGGLE BETWEEN COURSE AND FINE MODE WHEN NAVIGATING TO THE POINT (USE COURSE TO VIEW FASTER UPDATES FROM A DISTANCE, FINE TO ZERO IN ON THE POINT).

It is highly recommended to store the “as staked” position (versus the design position) - press the Measure or Enter key to activate the observation. Depending on the user defined settings in the Survey Styles/Stakeout menu, the delta differences between the stakeout and design positions may be displayed (also stored) and the staked point


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name/code assigned (either the next available point name or the design designation/design name or design code).

Stakeout Lines

In order to use this option, a line must be defined either by a starting point, azimuth, and grade, or by selecting start and end points (existing points already in the Job database or by pressing the Measure softkey to observe a point at the current location). Once a line has been defined, the system allows the definition to be named and stored for use in the future (accessed by using List to display any lines previously stored in the Job database.

After delineating the parameters of the line, the following options (listed under the Stake field) are displayed to define the positions on line to be staked:

To the line directs the user to a point on the line nearest to the current location of the Rover (this is essentially a right angle intersect from the current position to the defined line).

Station on the line navigates to a specific station on the defined line at a defined station interval.

Station/offset from line is similar to Station on the line except that it directs the user to a specified right angle offset from the defined line (either right or left).

Slope from line allows the user to define a Grade and horizontal offset (both left and right) at right angles from the currently defined line. The grade may be defined by Horizontal and vertical distance, Grade and slope distance, and Grade and horizontal distance from the defined line.

After the line and stakeout options have been defined, the screen displays direction and distance to the target as discussed under the above section for point stakeout.


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Stakeout/Arc

This routine is virtually the same as Stakeout/Lines except for the definition of a curve instead of a line. Again the defined curve may be stored (Arc Name) for future use. The arc Stake To options are the same as staking a line with the following additions:

Intersect point of arc directs the operator to the intersection of the two arc tangents (PI).

Center point of arc directs the operator to the radius point of the defined arc

Defining Stakeout targets with Map

In addition to setting up the point, line, and arc stakeout as above, ACCESS allows the targets to be designated by clicking on a DXF/Shape image in the Map view. In the Map view, click on the up arrow to access the Layers option, then check the appropriate layer twice to display the dashed box – this activates the map image for stakeout operations:

Enable layer to be selected Selected Points and Lines

Once items have been selected pressing a blank area of the screen will produce a context

sensitive menu of options: With Points selected With Lines selected


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Stakeout/Terrain Models

After uploading and selecting (a list appears after selecting the Terrain Models field) digital terrain model to the ACCESS, the system displays the current horizontal position and the cut or fill from the current position to the selected design surface. This option eliminates the need to grid a project in order to stake overlot cut and fill values.


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Stakeout/Roads

This function allows the operator to stakeout road alignments by station and offset. If templates are employed, the station and offset of any node may be located as well as any interpolated position as defined by the alignments and template parameters. The “catch” as defined by the cut/fill slopes in the templates can also be easily found using these routines – once the “catch” is actually located, it can be offset both vertically and horizontally. Superelevations and widening may also be applied to the template assignments.

The current Station and Offset can be incrementally changed by pressing the Sta+ or Sta- softkey. Pressing the right arrow on the Station field accesses a List of all Stations.

NOTE THAT IN ADDITION TO ANY REGULAR STATIONS THAT MAY BE SPECIFIED FOR STAKEOUT, THE SYSTEM AUTOMATICALLY HIGHLIGHTS THOSE ODD STATIONS THAT MARK AN EVENT IN THE ALIGNMENT SUCH AS A POINT OF CURVATURE, ETC.

Similar to the Station selection, all Offsets can be accessed by pressing the right arrow on the Offset field.

Additionally, ANY Station and Offset can be keyed into the respective fields for stakeout. In addition to the plan view stakeout display like the one for staking points, the ACCESS controller also displays a cross section view available under the XS softkey.


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For slope staking, select the Side slope Offset from the List. The display is similar to the one used for staking points.

The Side slope cross section display (XS) details the current slope vs. the design slope.

Once the “Catch” has been established and measured the screen displays the horizontal and vertical distances to the hinge point and the distance to the centerline. Using the Report softkey displays the horizontal and vertical distances from the catch to each node on the template.


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After the Catch is accepted, the prompt for the Construction Offsets is displayed (if values other than zero were entered).

ACCESS allows the use of Station Equations which can be created and edited under ROADS/Define/Edit.


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Stakeout/Alignments

Similar the Road Stakeout, staking Alignments allows targeting Stations and offsets on horizontal and vertical alignments (including DXF and Shape files). The Alignments can be imported files or created by selecting point ranges, lines/arcs on the Map, or selecting points on the Map.

Create from existing points Create from line(s) in Map view

Create from point(s) Map view Select from imported files

Initial Alignment stakeout display Map view of Alignment & Offset


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STAKEOUT RESULT FORMATS

Under the Configuration Menu/Survey Styles select any Real Time survey method and click on the Stakeout options – setting the Format section as below produces the stakeout results in specific formats:

Point –Stake markup Line/Arc Stake markup

DTM Stake markup Road Point Stake markup


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MENU DETAILS

This sections details available menu options that have not already been discussed in previous sections.

ACCESS MAIN MENU

ROADS

Allows creation of horizontal and vertical alignments and template/superelevation & widening station assignments.


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The Horizontal alignment consists of tangents and arcs (including spirals):

The vertical alignment consists of VPIs, circular and parabolic curves:


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ROAD TEMPLATES – allows creation/editing of cross section templates with graphic view:

Template/Superelevation and widening assignments:

After the road is created/imported it can be reviewed in plan and cross section view (Note the Station and offsets can be advanced by using the arrow keys):


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Road Reports:


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SETTINGS

Survey Styles - Default choices are: 3600 5600, FastStatic; PPK, RTK, RTK & Infill and Series S, although there may be user defined GPS styles in additional to the configuration for total stations (the 3600 5600 and Series S Styles are for Trimble Robotic Total Stations).

THE STYLES DICTATE HOW THE DATA COLLECTOR AND INSTRUMENT BEHAVE

DURING THE COURSE OF THE SURVEY. ONLY ONE STYLE IS IN USE AT ONE

TIME, HOWEVER MANY STYLES CAN BE USED IN A PARTICULAR JOB WHICH

ALLOWS BOTH RTK INFILL WITH POST PROCESSING WHEN THE RADIO IS DOWN

AS WELL AS CONVENTIONAL “INFILL” WHEN GPS CONDITIONS ARE ADVERSE.

WHILE THE RTK MEASUREMENT IS SET TO 1 SECOND AND IS NOT ABLE TO BE CHANGED, THE FAST STATIC, PP INFILL AND DATA LOGGING STYLES CAN BE USER DEFINED. HOWEVER, THE PP INFILL AND DATA LOGGING RATES ARE USUALLY SET AS FAST A POSSIBLE (AT LEAST TWO MEASUREMENTS SHOULD BE TAKEN) IN ORDER TO MINIMIZE FIELD TIME. AS A RESULT, THE STORAGE REQUIREMENT CAN BE LARGER THAN THE CAPACITY OF THE STORAGE AT THE BASE RECEIVER.

GPS Survey Styles


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RTK real time kinematic which allows survey grade data collection, stakeout, and complete transformations – ALWAYS requires radio contact between base and rover(s) – requires initialization

RTK & Infill real time kinematic and selectable post process infill (the operator can switch to raw data collection when necessary) which allows survey grade data collection, stakeout, and complete transformations – allows post processing of radial base/rover vectors when the radio link is down – requires initialization

RTK & Data Logging real time kinematic and continual raw data collection which allows survey grade data collection, stakeout, and complete transformations – ALWAYS logs raw data for post processing, requires the radio link – requires initialization

FastStatic collects only raw measurement data for post processing – normally used for networks and maximum precision – does not require initialization

PP Kinematic post processed kinematic - precision is the same as RTK –requires initialization but not radio link between base and rover

RT Differential real time differential which allows mapping grade data collection – ALWAYS requires radio contact between base and rover(s) – does not require initialization

RT Differential & Data Logging real time differential and continual raw data collection which allows mapping grade data collection – ALWAYS logs raw data for post processing, regardless of the radio link status – does not require initialization

Options – switches various survey options on/off (GPS surveying for example).

Feature libraries – - In addition to point positions, the ACCESS controller also offers the ability to enter specific alphanumeric attribute information. The Code field is a component of a particular point definition, and as such is automatically created each time is observed or entered through the keyboard. Code data can be edited under the JOBS/Point Manager routine at any time by highlighting the appropriate record and pressing Enter. Codes may be up to 16 characters long along with whatever attributes the user cares to setup (the Codes & Attributes are easily created in TBC) When taking observations, the Code defaults to the previously entered value. The information generated in the Code field is passed through to the TBC database which features several GIS data output formats.


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INTERNET SETUP/CONNECTION/REMOTE SUPPORT


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GENERAL SURVEY MENU

JOBS MENU

The Jobs Menu is basically data management and editing. In addition to creating/opening Jobs, the data can be reviewed with some editing capability and exported to another Jobs and files.

New job – creates a new Job database, see page 32.

Open job – Open/Select Job also allows a Copy to be made from a master file, providing control and consistency for specific sites.

Review current job – displays a chronological listing of all Job activity and allows Point Code and antenna height edits. Points can also be deleted/undeleted.


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Point manager – Similar to Review current job but lists only Point data. Note that the Point Manager will display and allow edits of Point IDs, Target Heights, Code and Attribute, and Coordinates depending on the Display choice:

QC graph – graphs precisions, std errors, elevations and target heights.


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Map of current job – see page 24.

Properties of current job – displays and allows changes to the current Job settings (coordinate system, units, etc):

Copy between Jobs – allows Calibration/Transformation and Point copies between jobs:

Import/Export – send/receives data/files from various devices and formats, (for Trimble Business Center upload/download, see page 42):


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The Map view will not only show the survey data, roads, DTMs, and DXF files, but will also allow georeferenced images (jpg and jpw for example ). The coordinate system and units in the world file (jpw) which references the image MUST be the same as the Job file and share the same file name.


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KEY IN MENU

Points - user entry of point values either in WGS84 or local latitude/longitude/height or grid northing/easting/elevation as well as Feature Code/Attribute and point quality (Control Y/N)

Lines - specifies line definition for stakeout from two points or a single point with azimuth/distance/grade. Arcs - similar to the line key in, requires two of three key components to compute the curve.


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Alignments – allows the creation of alignments by point ID range, including offsets:

Notes -allows entry of commentary, HOWEVER THIS TEXT DOES NOT REPRESENT POINT ATTRIBUTE INFORMATION!


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MEASURE MENU

Measure topo – see page 137

Measure Codes – see page 138

Continuous topo – see on page 139

Station and offset

Measure – direct link to a measurement mode that computes the normal position but also computes the Station and Offset relative to a user defined Line, Arc or Road (same as Stakeout/Roads/Position on Road)

Stakeout – direct link to stakeout a position defined by Station and Offset relative to a user defined Line, Arc, or Road (same as Stakeout/Roads/Station and Offset)

Stakeout – see STAKEOUT section on page 142

Site Calibration – see page 125

Initialization – see page 136

Swap base receiver - allows the use of multiple Base receivers in order to close an otherwise radial survey

End Survey – closes the survey operations and can power down the instrument.


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COGO MENU

Incorporated in the ACCESS firmware are several routines to allow the operator the ability to field compute points using familiar coordinate geometry functions.

While using the COGO functions, note that bearings and distances may be defined by existing points in the database by highlighting the appropriate field, pressing the right arrow key, and then pressing the Calc softkey. This will display a calculator with an azimuth softkey that will access point numbers.

The COGO functions are as follows:

Compute Inverse allows inverse calculations including the option to view the data in either Grid, Sea Level, or Ground distances (accessed by using the Options softkey, note also that coordinates may be viewed as Grid or Local/WGS84 lat/long).


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Compute Point computes standard intersection values using Bearing-Dist, Bearing-

Bearing, Dist-Dist intersects as well as Bearing-Distance from a specified point. This option also allows the conventions described above to define points, bearings, and distances.

NOTE THAT AZIMUTHS CAN BE DETERMINED FROM THE SUN BY MODIFYING THE

AZIMUTH ORIGIN FIELD TO “Sun” (observing a reference point on a shadow cast by the

target requires a “Sun Angle” of 0, casting a shadow from an observed reference point

to the target requires a “Sun Angle” of 180). When these offsets types are used (Sun,

True North, Mag North, and Grid 0) be sure to store the results as AZ/HD/VD to ensure

the offset point will move if the base is repositioned to an accurate position (when for

example the Base was started with the Here key and an OPUS result was obtained later

for the control). See Data Transfer on page 42.

Compute Volume computes volume of existing surface


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Compute azimuth determines azimuths Between two points, Bisected Azimuths, Bisected corner, Azimuth plus angle, and Azimuth to line offset. Component values can be derived from existing points in the Job database. Additionally, the units used to describe the azimuth may be input as Degrees, Minutes, Seconds (separately), Mils, Grads, or Radians.

Compute average determines the average of multiple observations of a point (Store Another) and displays Standard Deviation.

Area Calculations determines the area, perimeter and allows parallel and hinge area cutoffs


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Arc solutions – options include radius, delta, degree arc and degree chord and layout options.

Triangle solutions – options include Side/Side/Side, Angle/Side/Angle, Side/Angle/Angle, Side/Angle/Side, and Side/Side/Angle


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Subdivide a line allows a line (which may have been stored previous with a user specified name) to be subdivided by Fixed segment length or Fixed number of segments as well as normal (right angle) offsets either left or right

Subdivide an arc computes by Fixed segment length, Fixed number of segments, Fixed chord length, or Fixed angle subtended. Includes radial offsets (including Vertical offsets) and also allows the conventions described above to define points and distances.


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Transformations is used to transform a single point, or a selection of points, using one or a combination of Rotation, Scale, and Translations. When performing more than one translation, the order is always Rotation, Scale, then Translation. BE VERY CAREFUL HERE, THESE OPTIONS ALSO MOVE THE LAT/LONG VALUES OF OBSERVERD OBSERVATIONS.

Traverse allows the user to compute a series of points (traverse) with an azimuth, distance, and vertical difference and perform a Compass adjustment. This option also allows the conventions described above to define points, bearings, and distances.

Taped Distances creates points using a graphical right angle and distance interface to define rectangular structures, such as a building or building foundations

Calculator – complete calculator functions, including trig. Can be setup as a standard or RPN style and allows access to the database to define azimuth and/or distances between existing points.


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INSTRUMENT MENU

The Instrument Menu offers various details on the status of the system, including the GPS SVs as well as the receiver.

GNSS Functions allows automated connection to Base or Rover, Bluetooth connect options, etc.

The Satellites option (also available by tapping on the satellite icon on the right menu bar) displays a sky view of all SV positions in view, the List option displays the SV elevation, azimuth, and signal to noise ratio. It also allows the user to disable a SV – DO THIS WITH GREAT CARE!


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The Position option displays the current Rover receiver position with the option to also view the position of the Base. This is available without a Job being open or a Survey activated.

Receiver Status and Settings simply display the current power and memory available, the GPS date/time, and the onboard firmware options/versions.

Similar to the Position option, Navigate to Point allows GPS activity without a survey being active. HOWEVER, THIS MODE USES CODE PHASE POSITIONING, NOT SURVEY GRADE VALUES!


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INDEX

ACCESS data formats ........................... 108 ACCESS GPS SITE CALIBRATION ..... 125 Addendums

Coordinate System Manager .............. 179 Data Marketplace ............................... 192 Datums ............................................... 177 Feature Coding for MicroStation/Geopak

........................................................ 182 Grid vs Ground ................................... 180 Issues ................................................. 193 Trimble Connected Community/Access

Service/AccessSync ........................ 183 Alignments ............................................... 96 Antenna height ...................................... 138 Antennas ................................................. 11 Base options .......................................... 111 Base radio ............................................. 112 Baseline Processing & Evaluation ........... 72 Bluetooth connections ........................... 114 COGO MENU ........................................ 167 Cold Boot ............................................... 107 Continuous points .................................. 114 Continuous topo .................................... 139 Control Segment ....................................... 9 Conventional Traverse Adjustment ......... 91 Coordinate Seeding ................................. 17 CORS Stations ........................................ 18 Creating a Project .................................... 37 Creating/Exporting Alignments ................ 96 Data loggers ............................................ 11 Datum & Coordinate Systems ................. 17 Defining Stakeout targets with Map ....... 146 Duplicate point tolerance ....................... 114 Dynamic

Fast Static ............................................ 19 Kinematic .............................................. 19

Export .................................................... 122 Exporting ............................................... 102 Exporting TBC/ACCESS data using Style

Sheets ................................................ 106 Fast Static ......................................... 10, 19 Feature Libraries ................................... 158 Field Procedures

Power Considerations .......................... 31

Field Procedures & Startup – Post Processed ............................................. 31

Forced Power Down............................... 107 General System Requirements &

Connections ............................................ 9 GEOID Models ......................................... 16 GEOID12a ............................................... 18 Getting Started w RTK ........................... 107 GPS Method

Dynamic ................................................ 18 Static ..................................................... 18

GPS Site Calibration ...................... 117, 128 GPS Survey System Definition & Capabilities

................................................................ 5 Graphs ..................................................... 21 Horizontal control ..................................... 17 Import ..................................................... 122 Import to a TBC Project ........................... 42 Initialize .................................................. 136 INSTRUMENT MENU ............................ 173 Job Templates ....................................... 117 JOBS MENU .......................................... 160 KEY IN MENU ....................................... 164 Kinematic ........................................... 10, 19 Loop Closures .......................................... 77 MEASURE MENU .................................. 166 Measure points ...................................... 137 MENU DETAILS .................................... 153 Multiple Edits ............................................ 52 Multiple Observations .............................. 17 Navigating the ACCESS screens ............. 24 Network Adjustments ............................... 79 Network Design Parameters .................... 17 New Project ............................................ 120 NGS control information ........................... 17 Observed control point ........................... 113 Occupation Schedule ............................... 23 Planning ................................................... 16

GPS Project Observation Schedule ...... 35 GPS Station Observation Sheets .......... 34 Graphs .................................................. 21 Network Parameters ............................. 17

Point Management Advanced Select ................................... 48 Duplicate Points .................................... 44


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Exploding Points ................................... 51 Multiple Edits ........................................ 52 Select ................................................... 48 Select Points ........................................ 48 Select Points w/Filters .......................... 50 Selection Explorer ................................ 52

Power Management .............................. 107 Power source......................................... 107 PP Infill .................................................. 140 Processing

Solution Summary Ratio .................................................. 73 RMS .................................................. 73

Solution Summary Solution Type .................................... 73

Project Requirements .............................. 16 Projects & Data Flow ............................... 16 Quality Control Records ........................ 140 Rapid point ............................................ 113 Redundancy ............................................ 18 ROADS DETAILS .................................. 153 Rover options ........................................ 110 Rover radio ............................................ 111 RTK ................................................. 10, 107 RTK (On The Fly) .................................... 11 Select

Advanced Select .................................. 48 Select Points ........................................ 48 Spreadsheet Filters .............................. 50

Selection Explorer .................................... 52 Site Calibration ............................... 114, 131 Space Segment ......................................... 9 Stakeout ................................................. 114 Stakeout Arcs ......................................... 146 Stakeout Lines ....................................... 145 Stakeout Result Formats ....................... 152 Stakeout targets with Map ..................... 146 Stakeout/Alignments .............................. 151 Stakeout/Points ...................................... 142 Stakeout/Roads ..................................... 148 Stakeout/Terrain Models ........................ 147 Start Base Receiver ............................... 124 Static .................................................. 10, 19 Survey Styles ........................... 26, 109, 157 TBC Setup Options .................................. 13 TBC SITE CALIBRATION ...................... 131 TGO to TBC Conversion .......................... 12 Topo point .............................................. 113 Trimble Software ...................................... 11 Trimble SV Planning Software ................. 20 User Segment ............................................ 9 Using CORS ............................................ 62 Using OPUS ............................................. 67 Using RTX Post Processing ..................... 69 Vertical control ......................................... 18 Views ....................................................... 53 Warm Boot ............................................. 107

NOTE: THE FIELD DATA OBSERVED/USED IN THE CLASS ALONG WITH VARIOUS

UTILITIES, GEOID MODELS, AND QUICK GUIDES ARE AVAILABLE AT OUR WEBSITE:

www.gpstraining.com/downloads

http://www.gpstraining.com/downloads


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ADDENDUMS

THE EVER MOVING DATUM, EVER CHANGING EARTH CONUNDRUM

Being “star” based, one of the many things GPS has reinforced is the fact that the physical Earth is a dynamic structure, continually changing shape and dimension over time. This means of course that any given measurements of the Earth must be considered not in three dimensions (XYZ) but in four (XYZ and Time). Since the satellites in the GPS system are not conditional on the local movement of the Earth, that presents surveyors with a relatively new set of problems when using established coordinate systems such as State Plane and UTM or even user defined systems based on “accurate” global values (latitude, longitude and ellipsoid height). As more and more spatial information is integrated into our daily lives (GIS, location based services, etc) the disparities between a “fixed” measuring platform and a constantly changing target become more acute. This document will be confined in a general way to the two most basic Earth changes (the movement of the center of mass of the Earth and shifts in the “local” Earth surface) and specifically how this movement is realized and dealt with in the Trimble Business Center (TBC) software.

To begin, in the context of this document the word accuracy is meant to describe how well a position on the Earth is known and can be repeated (global coordinates like latitude/longitude/height) and the word precision is meant to describe how well the relationships between several points on the Earth are known and can be repeated within themselves (delta XYZ). At the end of the day, a boundary surveyor is more concerned with property corners relative to the section or legal monuments that control the survey (precision) as opposed to their global accuracy. However, if the surveyor publishes a boundary survey purported to be on an accurate basis (required for State Plane/UTM) or wants to make the survey portable across a

multitude of coordinate systems (highly recommended), then both accuracy and precision are in play.

The datum discussed here will be generally the basic WGS84 which is the foundation of the GPS system and GRS80 which is the basis for NAD83. Of first note is the fact that the ellipsoidal structure of the two are for all practical purposes the same, that is the semi major/semi minor and flattening parameters are virtually identical for a vast majority of survey purposes. Furthermore, in the original realization of the NAD83 datum, both NAD83 and WGS84 shared the same physical center of mass of the Earth which is why when using the NAD83 (Conus) datum in TBC the Local and Global lat/longs/hts will be identical (the Molodensky transformation values are set to zero). Over time however, the center of the WGS84 ellipsoid shifts with the current dynamic center of mass of the Earth which means that the WGS84 and NAD83 lat/long/hts are no longer the same. To account for the differences there have been new realizations of NAD83. This is evidenced by using the NAD83 CORS96 and NAD83 2011 datum transformation in TBC wherein a seven parameter transformation performs the shift between the two datum (NAD83 and WGS84) and the Local and Global lat/long/ht values are not the same. Since its inception, the NGS OPUS utility has been based on the NAD83 CORS 96 2002.00 realization but on July 15th, 2012 that changed to NAD83 2011 2010.00 (the last number in the name, 2002.00 and 2010.00 refers to the epoch date in time). The new realization of NAD83 also includes adjustment of the CORS stations themselves.

Dealing with all this is basically a matter of choosing the appropriate system in the TBC software, however there are a couple of issues here:

First, does your project require TRUE WGS84 values or are the Local (NAD83) values sufficient? With the exception of the military (there is no NAD in the Middle East for


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example) true WGS84 is rarely called for. Given the idiosyncrasies of TBC if only Local values are required it is simpler by far (although technically incorrect as far as the Global values are concerned) to use the original NAD83 datum (with transformation values of 0,0) as in the following Example 1.

TBC Ver 2.70+ will do the following when either the NAD83(Conus)(Molodensky) or NAD83(Conus) CORS96 or NAD83 2011 (both are Seven Parameter) datum are chosen when creating a Project/selecting a coordinate system and either CORS data sheets or OPUS XML files are imported (note that both NAD83 (Conus) and NAD83 2011 come stock in TBC, NAD83 CORS96 must be created as in the next section):

Example 1. Using the NAD83(Conus)(Molodensky) datum which is the default when selecting US State Plane 1983 from the Coordinate System Manager means using the original realization of GRS80 (note that the Molodensky transformation values are set at zero).

If a OPUS XML file or CORS station datasheet is imported into TBC the Local values will match exactly with the NAD83 values on the datasheet/XML, even though the CORS/XML datasheet may actually be in NAD83 2011. Note too that the Global values will also exactly match the Local values, in this case the Global values are incorrect.

Example 2. Setting up a Project using a NAD83 (Conus) CORS96 or NAD83 2011 State Plane coordinate system means using a Seven Parameter Datum Transformation to either the CORS96 Epoch 2002 or 2011 Epoch 2010 realization of NAD83.

If an OPUS XML file or CORS station datasheet is imported into TBC the Local values will match exactly with the NAD83 values on the datasheet/XML, even though the CORS/XML datasheet may actually be in NAD83 2011. Note that the Global values have been transformed (both the Global values and the Grid coordinates have been derived from the imported NAD83 values that have been transformed and projected).

NOTE: The new NAD83 2011 datum is the basis for the new Geoid12A and should also be used with the new NGS Absolute Antenna models.

VRS USERS BEWARE!!!!

As of Survey Controller Version 12.49 and Access Ver 2012.20 – when using a VRS system

the Trimble data collectors ASSUME that the broadcast position is WGS84. If that is NOT the

case (many VRS systems are now broadcasting a NAD83 2011 position) AND the controller coordinate system/datum transformation is using the seven parameter transformation (as

referenced above in the NAD83 COR96 and NAD83 2011 systems), ALL VALUES WILL BE

WRONG!!!!!!! For example, if the VRS is in fact broadcasting NAD83 2011 and Colorado State Plane NAD83 2011 is used as the coordinate system, the Trimble data collector will interpret the broadcast lat/long/height as WGS84 (which is incorrect) and the transformed Local value and projected Grid coordinates will also be incorrect on the order of multiple feet, both horizontally and vertically.

The work around is to use the original NAD83 (Conus) coordinate systems in the controllers and

then transform the values using HTDP IF necessary.


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COORDINATE SYSTEM MANAGER

To create a NAD83 CORS96 State Plane coordinate system in TBC, go to Tools/Coordinate System Manager. Under Edit select Add New Coordinate System Group to create a folder for the new system(s), US State Plane 1983 CORS 96 for example. Once the new folder is created go to the existing US State Plane 1983 group, highlight the desired coordinate system (Colorado Central 5052 for example) and “drag” it to the new folder. Once the coordinate system has been copied, right click on the coordinate system icon and select Edit. The Datum box allows a new datum transformation to be chosen, select NAD83 (Conus) CORS96 from the list (if you are using CORS96 be sure the geoid model is set to Geoid09, if you are using NAD83 2011 be sure to use Geoid12a) and press OK to save the edit (the coordinate system can be renamed as well). When exiting from the Coordinate System Manager be sure to save the Current.csd file when prompted.

Note that the Coordinate System Manager can be edited both by creating new coordinate systems as above and suppressing those systems that are never used (the United Kingdom Ordinance Survey grids for example can be suppressed by highlighting the United Kingdom folder, right click and select Hide – the shift and control keys will allow multiple selections). Using

the File/Export option allows the creation/export of selected coordinate systems (this includes custom Sites that have been saved in TBC) to Access or Survey Controller – this creates a

“Custom.csw” file that can be exported through Data Transfer/Send which will rename the file to “Custom.csd” and place it in the appropriate folder (Trimble Data\System Files for Access and Trimble Data for Survey Controller) or the renaming and export can be done manually through Active Sync and TBC/Direct Connect.


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“GRID” VS “GROUND”

Cartesian coordinates (the Northing and Easting values resulting from a projection) mathematically must reside on a flat plane commonly referred to as the grid and any coordinate geometry (COGO) computations such as an inverse are normally performed on this grid. A ground inverse on the other hand is the value between two points located at the average elevation of those particular points. In the two major published coordinate systems commonly used in the US, State Plane and UTM the grid is by default located at or near the ellipsoid which is usually below the physical ground and in that case the grid distance is somewhat shorter than the ground distance (see sketch on page 8) and the scale factor is at or about 1. In either case (the actual ground surface being above or on occasion below the ellipsoid) the difference between the two distances roughly works out to be 0.25’ per 1000’ of difference between the grid and ground per mile. For example, if a surveyor measured a ground distance of 5280 at a mean elevation of 4000’, the State Plane grid distance would be approximately 5279’ (0.25’ x 4 = 1’).

In order to use a State Plane or UTM coordinate system and deal with actual ground values the TBC software has an option named Local Site Settings which allows the user to scale the “grid” to a nominal “ground” location so that the “grid” and “ground” inverses are a tolerable match. There is however a particular caveat. Local Site Settings requires a Project Location which is the point at which the grid is scaled and can be identified in either northing/easting/elevation (Grid) or latitude/longitude/height (Local/Global) terms. If the Project Location is a local position in the survey (picking a central point in the project for example) the resulting “grid” inverse will in fact very closely match the “ground inverse”. However, if the “ground” coordinates are exported along with the “ground scale factor” they will NOT be reducible back to ellipsoid “grid” coordinates by simple multiplication of the inverse of the “ground scale factor” (1/x). If however the Project Location is set to 0 Northing and 0 Easting, the “ground” coordinates will in fact be reducible back to ellipsoid grid by simple multiplication of the inverse of the “ground scale factor” (1/x).


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Once the Local Site Settings have been entered and saved be sure to go to Project

Settings/Coordinate System/Local Site Settings and check the Project Location values.

Note that the Project Location values will be in Lat/Long/Ht format. If the Lat/Long/Ht

values are “?” the computations were not correct. This is almost certainly because the

Project Geoid Model does not extend to 0 Northing and 0 Easting. To solve this problem,

temporarily disable the Geoid Model (Project Settings/Coordinate System/Geoid

Model/None), set and save the Local Site Settings, and then enable the Geoid Model.

Again check the Project Settings/Local Site Settings to be sure the values are correct.

This problem does NOT occur in the data collector because the Project Location can only

be entered as latitude/longitude.

TSC2/TSC3 data collectors

If State Plane or UTM are used in Access or Survey Controller and “ground” coordinates are required the firmware offers a “calculated” or “keyed in” scale factor. In both cases the Project Location can only be entered in latitude/longitude terms. To derive the lat/long equivalent of 0 Northing, 0 Easting simply create a fictitious point with grid northing/eastings of 0,0 in the appropriate coordinate system and use the Options key in the Point Manager to view the WGS84 lat/long.

If the calculated scale factor option is used, the scale factor is a function of the user entered Project Height and local earth radius. Similarly, if a user defined coordinate system is created in Access or Survey Controller (by creating a Job with no projection/no datum and then calibrating on at least one horizontal grid and GPS point), the scale factor is a function of the user entered Project Height and local earth radius. A problem recently surfaced when scaling ellipsoid grid coordinates to “ground” as discussed in class and in the Addendum in the Training Guide. As explained, if when using Project/Local Site in TBC and in the controllers to create “ground” coordinates the Project Location values are local to the project the resulting “ground” coordinates cannot be reduced to the original grid values by simply multiplying the coordinates by the inverse of the “ground scale factor”. As stated in the Addendum, if the Coordinate Type is set to “Grid” and the Project Location values are set to 0 then the “ground” coordinates can in fact be multiplied by the inverse of the “ground scale factor” and be reduced to the original ellipsoid grid values. HOWEVER, if the TBC Project geoid model DOES NOT extend to 0 Northing and 0 Easting, the computations will be incorrect (this is most likely to occur if a UTM Coordinate System is used and/or in the case of a subgrid geoid model being employed) . To check for this situation go to Project/Project Settings/Coordinate System/Local Site and review the values. If the Project Location values are ? marks the scaling computation are in error. To remedy this problem temporarily disable the geoid model, set and save the Project/Local Site Settings and then re enable the geoid model. Be sure to then recheck the Project/Project Settings/Coordinate System/Local Site and review the values.


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FEATURE CODING FOR MICROSTATION/GEOPAK

When using the Feature Coding option in Trimble for producing the linework in real time on the Map of the Controller and post processed in TBC, the syntax of the Feature Code (the object) and the Line Control code (the action) must be in that order. That is, Feature Code first then the Line Control code separated by a space – for example the line string FL (flowline) ST (start new line) begins a new flowline element and does not connect to a previous flowline string. MicroStation/Geopak however requires the reverse syntax, that is ST FL to achieve the same effect. In order to enjoy both the automated linework in Trimble and still use the MicroStation/Geopak plotting routines there is a switch to flip the syntax in the MicroStation/Geopak software as below:

Checking the “Linking Code is After Feature” allows the linestring FL ST to be used in both Trimble and MicroStation/Geopak.


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TRIMBLE CONNECTED COMMUNITY/ACCESS SERVICES/ACCESSSYNC Trimble Connected Community (TCC) is Trimble’s internet “cloud” which currently allows various data transfers, data processing and publishing activities for survey Project data and components. This section is focused on the procedures required to transfer data between the field using the Access controller firmware option AccessSync and the office using Trimble Access Services (TAS) through Trimble Business Center (TBC) or logging on at myconnectedsite.com. TAS is a subset of TCC and has two main components, Survey Tools (OPUS data processing, File conversions, and GNSS forecasting, all at no charge and available without setting up an account) and Administration/Home (the primarily portal for data transfers to/from the office and field, essentially an FTP site, which requires setting up an account). If the user has the Access firmware on the controller and the license Maintenance Agreement is current there is no charge for this service. The following office procedures and protocols should be setup before the Access controller login and procedures are undertaken. The Trimble Access Services pdf manual can be found by logging onto http://tknsc.trimble.com/ and searching for “Trimble Access Services Help”.

INITIAL SETUP In the office:

There two principal actors and a utility at play when using TAS:

Site Manager – this role is used to setup both Users and project Sites where the data will be held in the cloud. While the Site Manager can “Upload” files from the computer to the cloud, this role is, as the name implies primarily for controlling permissions and data locations. Sitemanager is the initial unchangeable

username when registering the Organization for the first time on TCC.

User(s) – this role is the active operator in selecting files for upload/download from the computer to the TCC cloud.

TCC Explorer – an Add-In utility to expedite file transfers in Windows Explorer

To setup an account in TBC go to File/TCC/TAS or to myconnectedsite.com and click on Register Now and follow the prompts. A controller Serial Number with a valid Maintenance Agreement and the Trimble Dealer will be required to continue (the Dealer will be notified by Trimble that the Organization has been registered). Then a full company name and “TCC Organization Shortname/ID” are requested (the Shortname/ID will be the Organization name for all Administration and User data transfers in future logins. Finally, the email, password (minimum 6 characters, case sensitive alpha with at least one number and one punctuation mark character such as @,

#, *, etc.), country and time zone are required for submittal. Note that the Username is

forced to sitemanager, this cannot be changed.

http://tknsc.trimble.com/


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CREATE USER(s)

Once the organization has been registered, Users (with their own Usernames and Passwords) and Sites (cloud locations/filespace with their own permissions for said Users) can be created and edited through the sitemanager credentials.

Once logged on as sitemanager, go to Administration/Manage Users/Add User to create individual accounts necessary in both TAS (in the office) and AccessSync (in the field) for data transfers:

If a Site has previously been created the new user can be allowed to access that Site(s) by checking the Allow Access box(s) and a Default Site can be similarly selected.


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CREATE SITE(s)

Once logged on as sitemanager, go to Administration/Manage Sites/Add Site to create data locations necessary for TAS (in the office) and AccessSync (in the field) for data transfers:

If User(s) have already been created they can be permitted access by checking the Allow Access box.

Once the User(s) and Site(s) have been created the permissions can be edited through either Manage Users or Manage Sites.

Throughout the transfer process it is important to remember that there is not a direct connection between the office the the Access controller, rather the data is transferred to/from the office (through TAS/TCC Explorer) to the cloud or to/from the field (through AccessSync) to the cloud.

TCC Explorer

The TCC Explorer is an Add-In to the Windows Explorer and greatly simplifies the data transfer between the TCC cloud and the local computer. If the Trimble Access Installation Manager has been run the TCC Explorer has mostly likely been installed, if so at the lower right of the computer screen there should be an

icon on the Notification Area of the the Windows Explorer Task bar (it may be necessary to “customize” the Taskbar using Windows Explorer to show the TCC


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Explorer icon). If the TCC Explorer has NOT been installed run Trimble Access Installation Manager, available at http://www.trimble.com/Survey/Trimble-Access-IS.aspx then Downloads. Be sure to check the TCC Explorer box as below:

Right click on the TCC Explorer icon and the Login screen will be displayed. Use the credentials for the User (created above), NOT the Site Manager credentials.

Note that the TCC Explorer can be logged in automatically when Windows starts, OTHERWISE THE LOGIN PROCEDURE WILL NEED TO BE EXECUTED BEFORE USING TCC EXPLORER FOR THE ACTUAL DATA TRANSFER. Data can however, can be setup for transfer (see TRANSFERING FILES BETWEEN TCC AND THE LOCAL COMPUTER below) before logging in. Right clicking on the TCC Explorer icon also offers Settings such as Automatic/Manual sync and update frequency:

http://www.trimble.com/Survey/Trimble-Access-IS.aspx

http://www.trimble.com/Survey/Trimble-Access-IS.aspx


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Data management is now the key. If TAS is to be used for multiple, relatively small projects it is simplest to create a single Site for all those project types, if there are separate long term projects the data management is probably easier with a specific Site for each project. When using TCC Explorer to access the data the software will allow a specific local computer folder to be “synced” automatically to a specific Site in the cloud. The “sync” specification can be two-way (both from and to the Site in the cloud) or from the Site in the cloud to the folder only. In both cases, if there multiple copies of the same file the file with the latest date is retained. If specific folders are used in the TSC3 for each job and they are all linked to a specific Site, the same folders will be created as subfolders under the local computer folder that is “synced” to that Site. For example: a Site with the name of GENERAL SURVEY with permissions for all Users has a “2-way sync” to a local computer folder named ACCESS SYNC GENERAL (see “TRANSFERING FILES BETWEEN TCC AND THE LOCAL COMPUTER” below):


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In the field:

In order to connect the TSC3 with the cloud an initial login is required to establish the permission credentials and associate a particular Site in the cloud with the specific TSC3 account. The credentials will be those of the User setup earlier in TAS. To login be sure the TSC3 is connected with WiFi to the Internet and on the Access main page click on the top bar (which may display the company name depending on how the TSC3 was originally

configured, in this case the top bar displays TSC3MM.SDI) and complete the required fields. Once the credentials have been entered press Next in order to select the appropriate Site on the cloud and finally Next again to complete the login. This login process is only required one time per User/Site from that point forward AccessSync is available without logging in. Once the initial login has been completed the User and Site can be changed Offline or logging in again if necessary.


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NOTE: If there is an active Internet survey (VRS, etc.) it will take precedence over the AccessSync connection. AccessSync will not attempt to send a file over 8Mb.

Also, when active, AccessSync compares selected data folders on the controller with those on the TCC Site every 30 seconds so it is wise to exit AccessSync when not in use to avoid transfering unintentional or incomplete data.

TRANSFERING DATA FROM THE TSC3 TO TCC

After logging in as above, all activity on the TSC3 will be done under the AccessSync option.

The AccessSync screen shows the following:

Under the Folder Name column all folders including subfolders under the Trimble Data/User folder are displayed in sequence. Subfolders have a ] to the left of the name, for example ]1238 ORIG is a subfolder of TSC3MM and ]]Export is a subfolder of ]1238 ORIG. The check box on the far left shows the status of any given folder under the User folder (in this case TSC3MM). If the box is checked the folder will be synchronized with the TCC Site listed on the far right. The Status column shows the progress of the active data transfer to the TCC Site as well as any folders that have previously been synced (highlighted in green with a check mark as in the CLASS folder above). Once the transfer is complete the data is accessible from the office. Note also that if a file is transmitted with the same name as an existing file in the target folder, the existing file will be OVERWRITTEN without notification.

TRANSFERING DATA BETWEEN TCC AND THE LOCAL COMPUTER

On the local computer login to TCC Explorer. Browse to the destination folder (in this case ACCESS SYNC GENERAL) in Windows Explorer and right click the folder, select TCC Explorer and the dialog box will then offer a “1 way Sync” which will copy the data ONLY from the TCC Site to the selected folder or a “2 way Sync” which will synchronize the selected folder with the TCC Site. Typically, choose “2 way sync” then Select the Filespace (the cloud Site) to sync to and click “Sync to Filespace”:


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Once the relationship between the local folder and the Filespace (Site) has been

established TCC Explorer creates a subfolder for each User, a User/ To the Field subfolder as well as a To All Users subfolder (there are two Users below, RTKGPS and TSC3MM):

After selected data folders have been sent from the field to TCC they will be “synced” to the destination folder for use in the computer software:


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TRANSFERING DATA FROM THE OFFICE TO TCC/FIELD

When data needs to be sent to the field (point stakeout files, roads, etc.) simply create a folder with the data under the User/To the Field subfolder (to execute the transfer immediately, right click the TCC Explorer icon and select “Synchronize now”):

When AccessSync in the TSC3 is next selected the folder will be offered for download into the controller:


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DATA MARKETPLACE

TBC Version 3.30+ includes the Data Marketplace utility to interface and retrieve imagery information for importation to the TBC Project. A global coordinate system (State Plane, etc) must be present in the Project to open this utility opens to the Project area (in this

case using OpenStreetMap Planet:

Using the polygon tool icon the desired area can be outlined and imported into the TBC Project:

Note that the KML button allows an imported KML file to define the area of interest.


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ISSUES

Following are some of the perplexing issues/corrections in TBC (latest version 2.98/3.30):

1. In the latest TBC Version (3.40) the Ribbon can be “customized” to access the Data Processing routines used for OPUS submittals. To do so, right click on the Ribbon and click on Customize the Ribbon, select External Processing Services and choose a destination tab:

2. The Merge points on import routine now operates as would be expected (i.e. duplicates will be merged into a single point) – previously the points were duplicated in the database

EXCEPT when multiple observations have been made in the field and stored as Store Another – in this case TBC means the positions (which can be Exploded in TBC).

3. When importing a Job file the offsets connection now work properly (assuming the offset was stored as AZ/HD/VD) - previously this only worked if you imported the DC file.

4. The Corridor export now sends the DESIGN cut/fill slopes to the controller IF the export

option for “Side Slope element generate method” is set to “Replace” – previously only the THEORETICAL “catch” was exported.

5. A surface is still required in order to create a template with side slopes (unfortunate for those wanting to “key in” a road from a set of plans), however an alignment (below) can be exported and the templates created/assigned in the controller.

6. Alignments (horizontal with optional vertical) can be exported if the “RXL Road exporter

from surface” option is selected (even though there is NO surface present)

7. “Smart Text” still does not offer azimuth/bearings.

8. RTX Post Processing tests as follows (using a 9 hour static file):

I have continually compared RTX results against OPUS with every new version of TBC and the results are at least consistent, the horizontal is not too bad but the vertical is consistently around 0.10’. Also, despite my pleading, the RTX solution does NOT provide the stations used for the resulting position.

9. The DC file format is not supported in TBC!!! (see Data Transfer). This was an issue with documentation as the DC file was the only field record in people language that is organized and chronological. There is however a Survey Report available in the controller that details the field operations (this is available ONLY in the controller and does


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not allow edits). To create this report go to Jobs/Import-Export/Export Custom Format and choose Survey Report. When the Survey Report format is selected there is an option to select either All data, Field Book data only, or Reduced Coordinates only. There is also the option to have the data presented from the Antenna Phase Center to Antenna Phase Center (APC to APC) or from Mark to Mark (the raw data is reduced to ground point to ground point).

10. Projects created in TBC Version 2.98/3.40+ CANNOT be opened with earlier versions of TBC.

11. Beware using TCC to move static data files, there are instances where the cloud delivered

data DOES NOT WORK, however the same data downloaded by cable works fine. This seems to occur when the data types (Static, RTK, conventional) are mixed in the file. Stay tuned.

There surely are other items as well, I am sure the list is long, just getting into the latest version.

Documents

Master student's guide - Gps Training