SENIOR DESIGN I05009 AIRBORNE SENSING PLATFORM

PRELIMINARY DESIGN REVIEW2/18/05

JONATHAN FENTZKE – TEAM LEAD

JOSEPH O’DAY – MECHANICAL LEAD

ERIC GREENWOOD – AIRFRAME LEAD

JOHN PRIESTLY – RF LEAD

JEAN LAURIN – VISION LEAD

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EXECUTIVE SUMMARY

This preliminary design report outlines the progress made by the senior design team on

completion of an airborne sensing platform for the Center of Imaging Science.

Recently the government and private industry alike have begun to utilize Unmanned Aerial

Vehicles (UAV) for reconnaissance scenarios both on and off the battlefield. While UAV

technology exists for a wide range of military applications, there is a need by the US Forest

service for UAV technology capable of remote sensing tasks related to wild fires. The goal of

this senior design project is to design and build an airborne sensing platform test bed that will

allow the Center for Imaging Science to display there remote sensing technology.

The team utilized design and analysis methods outlined during the design project

management class and the Senior Design I course to design the airborne sensing platform using a

logical progression of steps. This report discusses the complete process in detail.

First, the team met with the project sponsor and determined the needs of the sponsor. This

information is captured in detail in the Recognize and Quantify the Need section of the PDR.

This section specifically explains the mission statement for the project. It also discusses the

information collected by the team to help them understand the scope of the project and the exact

needs of the sponsor.

The next section involves the concept development for the airborne sensing platform. The team

began by researching current technology available for UAV development and created subsystem

concepts based on the research conducted. After the initial team concept development, the team

conducted trade studies to determine the feasibility of individual subsystems. This information

was presented to the sponsor. Based on sponsor feedback, overall system concepts were

finalized. The Feasibility section of the PDR discusses this information. Pursuant to the concept

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development with the sponsor, the team in conjunction with the sponsor determined a set of

design objectives and specifications. This information guided the overall system selection and

design parameters to meet sponsor requirements and define measures of project success.

The team took into consideration all the aforementioned information when completing an overall

system design for the airborne sensing platform. This final design information is found in the

Analysis and Synthesis section of the PDR. It contains detailed drawings and pertinent

calculations to demonstrate the overall system design and implementation, as well as subsystem

configurations. The final design is an airborne sensing platform capable of piloted and

autonomous control of the aircraft that provides real time video and sensor feedback to the pilot.

At this time, the team has completed the major design portion of the project. The task to be

undertaken during the spring session of Senior Design II is system integration and testing. As

Senior Design II begins, the team plans to test components as they arrive from vendors and

complete the necessary machining and circuitry associated with the systems designed. Slight

design modification will occur as needed and systems integration into the airframe will then

begin. The completed prototype will undergo testing in preparation for demonstration to the

Center for Imaging Science at the end of Senior Design II in May.

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TABLE OF CONTENTSTable of Contents ............................................................................................................................. 5 Table of Figures ............................................................................................................................... 8 1.0 Team Organization and Work Breakdown Structure ................................................................ 9 2.0 Recognize and Quantify Need ................................................................................................. 10

2.1 Mission Statement ................................................................................................................ 10 2.2 Project Description ............................................................................................................... 10 2.3 Scope Limitations ................................................................................................................ 11 2.4 Key Business Goals ............................................................................................................. 11 2.5 Primary Market .................................................................................................................... 12 2.6 Secondary Market ................................................................................................................ 12 2.7 Innovation Opportunities ..................................................................................................... 12 2.8 Formal Statement of Work ................................................................................................... 13

3.0 Concept Development .............................................................................................................. 14 3.1 Communication ................................................................................................................... 14

3.1.1 Wireless Communication Scheme ................................................................................ 14 3.2 Guidance and Telemetry System ......................................................................................... 15

3.2.1 Vision Guidance System ............................................................................................... 16 3.2.2 Positioning/Telemetry System ...................................................................................... 17

3.3 Control ................................................................................................................................. 19 3.3.1 Piloted Control .............................................................................................................. 19 3.3.2 Partial Autonomous Control Systems ........................................................................... 20 3.3.3 Fully Autonomous System ............................................................................................ 22

3.4 Sensor Equipment ................................................................................................................ 23 3.4.1 Temperature Sensor ...................................................................................................... 23 3.4.2 Pressure Sensor ............................................................................................................. 23

3.5 Base Station ......................................................................................................................... 23 3.5.1 Base Station Configuration ........................................................................................... 24 3.5.2 Antenna ........................................................................................................................ 25

4.0 Feasibility ................................................................................................................................. 26 4.1 Communication .................................................................................................................... 26

4.1.1 Wireless Communication .............................................................................................. 27 4.2 Guidance and Telemetry System ......................................................................................... 28

4.2.1 Vision Guidance System ............................................................................................... 28 4.2.1.1 Camera Packaging Scheme ........................................................................................ 28 4.2.2 GPS ............................................................................................................................... 30

4.3 Control ................................................................................................................................. 31 4.3.1 Radio Control ................................................................................................................ 32 4.3.2 Partially Autonomous Control System ......................................................................... 33

4.3 System Level Feasibility ...................................................................................................... 35 4.3.1 Piloted Control .............................................................................................................. 37 4.3.2 Autonomous Control Capability ................................................................................... 37 4.3.3 Commercially Available Complete System Solutions .................................................. 39

4.4 Overall System Selection ..................................................................................................... 39 5.0 Objectives and Specifications .................................................................................................. 39

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5.1 Performance Specifications ................................................................................................. 40 5.2 Design and Implementation Specifications ......................................................................... 40

5.2.1 Platform Durability ...................................................................................................... 40 5.2.2 Fuselage ....................................................................................................................... 41 5.2.3 Dimension ..................................................................................................................... 41

5.3 Stability and Control ............................................................................................................ 41 5.3.1 Control Surfaces ............................................................................................................ 41

5.4 Electrical Systems ................................................................................................................ 42 5.4.1 Video ............................................................................................................................. 42 5.4.2 Global Positioning System (GPS) ................................................................................. 42 5.4.3 Transceiver .................................................................................................................... 42 5.4.4 Base Station .................................................................................................................. 43 5.4.5 Batteries ........................................................................................................................ 43 5.4.6 Possible Platform Features ............................................................................................ 43 5.4.7 Controller ...................................................................................................................... 45 5.4.8 Controller Receiver ....................................................................................................... 45 5.4.9 Onboard Processing ..................................................................................................... 45

5.5 Design Practices ................................................................................................................... 46 5.6 Safety Issues ......................................................................................................................... 47 5.7 Launch .................................................................................................................................. 47 5.8 Pilot ...................................................................................................................................... 47 5.9 Deliverables ......................................................................................................................... 48 5.10 Overall Period of Performance and Schedule .................................................................... 48

6.0 Design Analysis and Synthesis ................................................................................................ 49 6.1 Airframe Analysis ................................................................................................................ 49

6.1.1 #05008 Airframe Stability Analyses and Redesign ...................................................... 49 6.1.3 #05008 Airframe Weight Analysis - Cg ....................................................................... 51 6.1.2 Senior Telemaster Performance Analysis ..................................................................... 51

6.2 Motor Selection and Analysis .............................................................................................. 54 6.3 Structural Design and Analysis ............................................................................................ 55

6.3.1 Structural Design .......................................................................................................... 55 6.3.2 Structural Analysis ........................................................................................................ 57 6.2.4 Camera Mounting System Design ................................................................................ 65

6.4 Power Consumption ............................................................................................................. 65 6.5 Battery Selection .................................................................................................................. 65 6.6 Vision Guidance System Design and Analysis .................................................................... 66

6.6.1 Camera Design .............................................................................................................. 66 6.6.2 RF Link Budget Analysis .............................................................................................. 68 6.6.3 Communications System Design .................................................................................. 69

6.7 Telemetry and Stability Augmentation System Design and Analysis ................................. 70 6.7.1 Control .......................................................................................................................... 70

6.8 Launch .................................................................................................................................. 71 7.0 Future Plans ............................................................................................................................. 71 8.0 Budget ...................................................................................................................................... 72 9.0 Conclusion ............................................................................................................................... 72 Appendix A – Airframe Stability calculations ............................................................................... 74

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Takeoff Performance Equations Used ....................................................................................... 74 Stability & Control Equations Used .......................................................................................... 76

Appendix B – Cg Calculations ...................................................................................................... 77 Appendix C – Detailed structural drawings ................................................................................... 79 Appendix D – Path loss Calculations ............................................................................................. 84 Appendix E – Power Budget Analysis ........................................................................................... 87 Appendix G – Bill of Materials ..................................................................................................... 90

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TABLE OF FIGURESFigure 1: Work Breakdown Structure.............................................................................................9Figure 2: On-Board Communication System Architecture.......................................................... 15Figure 3: Vision Guidance System Diagram................................................................................ 16 Figure 4: Table of Communication Systems Trade Study Results.............................................. 28Figure 5: Table of Camera Selection Trade Study Results...........................................................30Figure 6: Table of GPS Trade Study Results................................................................................31 Figure 7: Table of Radio Controller Trade Study Results........................................................... 33Figure 8: Table of Stability Augmentation System Trade Study Results.....................................34Figure 9: Table of Autonomous Systems Trade Study Results.................................................... 35Figure 10: Table of System Level Feasibility Study.................................................................... 37Figure 11: Plot of CL3/2 / CD vs. Speed......................................................................................53Figure 12: CL / CD vs. Speed.......................................................................................................53Figure 13: Tabulated results of Telemaster performance analysis............................................... 54Figure 14: Rail Cage Assembly.................................................................................................... 56

Figure 15: Table of total weights.................................................................................................57Figure 16: Worst-case loading scenario........................................................................................58Figure 17: Decoupled stress scenario........................................................................................... 59Figure 18: Cross-section dimensions and section divisions......................................................... 59Figure 19: Centroid location and axis placement......................................................................... 60

Figure 20: Table of calculated values........................................................................................... 62Figure 21: Location of neutral axis...............................................................................................62Figure 22: Wiring Diagram of Camera System............................................................................ 68Figure 23: Vision Guidance System Diagram.............................................................................. 68Figure 24: Control System Diagram.............................................................................................70Figure 25: Projected Schedule...................................................................................................... 72

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1.0 TEAM ORGANIZATION AND WORK BREAKDOWN STRUCTURE

In order to conduct the design and analysis efficiently of the project subsystems it was

necessary to divide the team into subgroups based on area of expertise and previous experience.

The team was comprised of both mechanical and electrical engineers with a skill set that bridged

the gap between both disciplines. Most members of the team have some familiarity with design

and analysis outside their core area of study, which helped considerably with concept

development and other tasks. The three subgroups and there associated members can be seen

below in Figure 1.

Figure 1: Work Breakdown Structure

Although the team worked together to complete assigned tasks, the subgroups were divided

to provide the most efficient means for completing the project on time and under budget.

Airframe design and analysis was mainly concerned with the structural integrity and handling

qualities of the aircraft to be used in the project. Mechanical design and analysis centered on the

hardware mounting scheme, vibration damping, dynamic loading of the aircraft, and control of

the aircraft. The electrical portion centered on the communication system, vision guidance, and

power needs of the project.

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Airframe ElectricalMechanical

Eric Greenwood Joseph O’Day

Jonathan Fentzke

Jean Laurin

John Priestly

0500

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2.0 RECOGNIZE AND QUANTIFY NEED

2.1 Mission Statement

The purpose of the student design team is to design and build a guidance and navigation

system for an Unmanned Aerial Vehicle (UAV) for the Center for Imaging Science. This project

will produce a passively stable airborne sensing platform test bed with a vision guidance flight

control system, as well as to integrate onboard sensors allowing long-range remote sensing tasks

to be completed.

2.2 Project Description

An interdisciplinary team of senior RIT engineering students will complete a fully

functional airborne sensing platform test bed with assistance from the Center for Imaging

Science and the Mechanical and Electrical departments at RIT. The airborne sensing platform

utilizes an onboard guidance and navigation system comprised of video and telemetry

subsystems. These systems allow a pilot to complete remote sensing tasks at a maximum

altitude of up to 1,000 feet at a maximum range of 2 miles away from the pilot’s location. The

platform can also execute mission objectives autonomously based on its telemetry hardware.

The platform is capable of carrying a modular 3 lb payload provided by the Center for Imaging

Science in addition to the onboard equipment and sensors needed by the pilot to complete a

successful mission.

The platform gives real time continuous feedback to the base station from the video

camera, telemetry, and other sensors to allow the pilot to navigate the airborne sensing platform

beyond the pilot’s line of sight. Using GPS waypoint information, the platform can also target

an objective area while outside the line of sight of the pilot. Sensors for temperature, pressure,

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battery life, as well as the onboard processing allow the pilot to avoid catastrophic crashes and

remote sensing conditions that may be hazardous to onboard equipment or the platform itself.

The platform has been efficiently designed both electronically and aerodynamically to

provide a launch and loiter condition that allows it to carry out a maximum mission time of one

hour. Upon completion of the remote sensing task, the platform can be navigated back to the

base station and landed in a manor that preserves the integrity of the onboard equipment and the

platform structure.

2.3 Scope Limitations

The platform is limited in size and carrying capacity. It shall be designed to carry the

Center for Imaging Science payload and a navigation system. The platform must be portable and

provide a design that allows for future upgrades. Consideration will be given to providing power

and mounting space for as much additional equipment as possible. This initial airborne sensing

platform shall be a test bed for the Center for Imaging Science.

2.4 Key Business Goals

The project must be completed within the $10,000 budget and before the completion of the

academic year in May 2005. A working prototype shall be demonstrated to the Center for

Imaging Science. The prototype shall provide a means for the Center of Imaging Science to

conduct remote sensing experiments and continue further development with future senior design

projects.

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2.5 Primary Market

This project provides a relatively small and compact means of carrying out remote

sensing tasks related to forest fires. Because it is being designed and built to meet fire detection

needs, the primary market is the U.S. Forest Service and Center of Imaging Science. These

groups can exploit the platforms capabilities to display there new remote sensing technologies

currently under development.

2.6 Secondary Market

Recently the advent of autonomous technology has sparked a sharp increase in market

demand for unmanned aerial vehicles. The intelligence community including, but not limited to,

the Central Intelligence Agency, Department of Defense, and branches of the armed services are

all interested in acquiring UAV technology for reconnaissance and communication. The

airborne sensing platform is a perfect candidate for mid-range reconnaissance and target tracking

due to its relatively small size, payload capacity, and range.

In addition to military applications, the airborne sensing platform can be modified for use

in the commercial sectors. Its applications range for urban fire-fighting capabilities to traffic

detection and weather service applications. The modular design and large payload space allow

for quick adaptation to meet consumer demands.

Thus this product can be marketed to both commercial and government consumers as a

means of additional funding to the Center for Imaging Science.

2.7 Innovation Opportunities

Due to the nature of the project, the opportunity for innovation is high. The platform is

designed to modified and upgraded with ease. The additional payload capacity allows for

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additional sensors to be placed on board. This allows for innovation in the areas of sensor design

and packaging. Sophisticated weather sensors could be placed onboard allowing for scientific

research on weather conditions and patterns. Also, biological or chemical sensors could be

implemented to test for hazardous materials over a given area. This has applications in both

military and agricultural settings. Swappable camera packages could be implemented allowing

for spectral analysis via infra-red, ultraviolet, or other camera configurations. In addition, the

configuration of the control system allows for continual modification and improvement. Thus,

dynamic stability augmentation research and control theory applications can be implemented.

This would lead to a great deal of progress in completing autonomous remote sensing tasks for

students and faculty at RIT, as well as outside interests in the commercial and defense

communities.

2.8 Formal Statement of Work

The main objective of this project is to produce an airborne sensing test bed for the

Center of Imaging Science. The design will allow for platform portability while providing ample

space in the design envelope to allow for future upgrades and modifications. The platform will

house the Center for Imaging Science payload, as well as guidance and telemetry equipment. It

will have the capability to perform remote sensing tasks at distances at a maximum of two miles

away from the pilot location and loiter at altitudes of less than 1,000 feet. The system must

provide real time feedback to the pilot about the location and attitude of the platform to help

ensure mission success.

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3.0 CONCEPT DEVELOPMENT

3.1 Communication

After establishing the sponsor requirements, we began to develop concepts to manage the

communication needs for the airborne sensing platform. A very crucial design aspect of the

overall system architecture is the ability of the embedded system, on the plane, to communicate

real-time information back to the base station. The communication system must have the ability

to transmit real-time video and telemetry.

3.1.1 Wireless Communication Scheme

In order to meet the range requirements, and due to the nature of the airborne sensing

platform, a radio frequency (RF) wireless communication system best fit this application. An

analysis was performed to determine the RF frequency range best suited for this application. The

parameters that guided this study were data throughput, typical power consumption, free space

path loss, interference rejection, cable/connector loss, and freznel zone requirements. The main

frequencies under consideration were 900 MHz, 2.4 GHz and 5.8 GHz. Once we identified

several frequency ranges, we then developed two basic system architectures that could be

implemented to meet the needs of the communications system. The two architectures developed

were (1) a dedicated transmitter for video feedback and a separate telemetry system, and (2)

combining the telemetry system and video feedback system by utilizing the audio channel on a

video transmitter. The first architecture incorporates one transmitter/receiver combination to

send video feedback to the base station. The aircraft supports the transmitter and the associated

antenna, and the base station supports the receiver and its associated antenna. The video

transmitter is specifically designed for video, typically interfacing with a camera via standard

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coaxial connectors used in National Television System Committee (NTSC) systems. This

architecture also includes a separate transmitter/receiver combination, configured similar to

video communication above, as a telemetry system. The second architecture developed attempts

to minimize the number of transmitters supported by the aircraft. To do this the system utilizes

the audio channel provided by a standard wireless video transmitter to send telemetry data back

to the base station. Byonics offers the Tiny Track product, which encodes GPS data on the audio

output of a camera. The base station then utilizes a standard sound card and a software package,

such as AGW Packet Engine (AGWPE), to extract the data received over the audio channel.

Considering our application does not require sound feedback, this may be a viable option.

Audio In

Video In

TTSMT Encoder

Camera

Telemetry Data

Figure 2: On-Board Communication System Architecture

3.2 Guidance and Telemetry System

In order to complete remote sensing tasks successfully, it is vital to utilize a guidance and

navigation system onboard the airborne sensing platform. This system provides navigational

cues to the base station and pilot. The concepts described here can be used as stated alone or in

concert to provide varying levels of feedback and upgradeability. They range from stand-alone

vision guidance to fully autonomous flight options.

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3.2.1 Vision Guidance System

The requirement of real-time piloted control at long distances necessitates a platform with

a vision guidance system. The vision guidance systems allows the pilot to maintain absolute

reference to the horizon and determine local topographic information to aid in control and

attitude determination when the airborne sensing platform is not in the pilot’s line of sight.

3.2.1.1 Camera Packaging Schemes

The team developed two primary concepts for the ways to implement a vision guidance

system. The first concept involved a commercially available system consisting of a video

camera and a transmitter packaged together. The alternative concept involved a stand-alone

camera and a separate transmitter. Based on physical dimension constraints and integration

difficulty the team elected to pursue a stand-alone camera and transmitter, allowing for

maximum design flexibility and upgradeability as well as ease of system integration. Figure 3

represents the system diagram for vision guidance.

ImageryCamera Transmitter Reciever Base Station Pilot

Figure 3: Vision Guidance System Diagram

3.2.1.2 Camera Options

Camera units are commercially available with a large array of attributes. The two main

types of imagers available for video cameras are Charge Coupled Device (CCD) and transistor

type Complementary Metal-Oxide Semiconductor (CMOS). CCD imagers provide a more

accurate picture than CMOS imagers due to their superior electronic shuttering and smaller

amount of noise within the imager.

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Most cameras are available in black and white or color. Color cameras generally require

more power than their black and white counterparts. The team discussed a concept involving

night vision and infrared. However, at this time the sponsor deems them to be outside of the

scope of this project. They are possible upgrades for future designs.

A concept for a camera that comes capable with an audio channel developed from a

desire to encode and transmit telemetry or other sensor data on that channel. Another important

feature considered was the minimum amount of light that will produce adequate pictures, or

LUX. Cameras with a small LUX can operate with less light and thus are more desirable. In

addition, the format of the camera output signal is important. To alleviate integration concerns

the output should be the American standard, NTSC. This will facilitate integration with the

communication system and allow the base station to easily convert and display the video signal.

3.2.2 Positioning/Telemetry System

The two mile range requirement drives the need for some type of telemetry data from

onboard the plane to be transmitted back to the base station once the plane is beyond line of

sight. For a successful flight and adherence to the defined mission route, the pilot would need to

know where the plane is, where it is going, and how fast it is getting there. To this end, some

necessary attributes of a positioning telemetry system will be latitude, longitude, altitude,

headway, speed, and time.

Brainstorming resulted in five feasible options. Commercially available Original

Equipment Manufacturers (OEM) modules and engines exist for providing telemetry bases on

the standard Global Positioning System (GPS). Secondly, a wireless signal could be used to

relay the attributes of the plane’s motion back to the base station. Thirdly, an inertial guidance

system using a combination of accelerometers and rate gyros could be used to determine the

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motion of the plane relative to the pilot/base station location. This type of system is commonly

used on fighter aircraft. Magnetometry was also considered to be an option. This type of system

relies on the magnetic field of the Earth to provide relative positioning. Lastly, a signal

triangulation scheme could be used to find the plane’s position

Based on ease of implementation, the wireless signal option was discarded. In addition,

based on system usability, the signal triangulation scheme was also discarded as a viable option.

The limited accuracy and high susceptibility towards interference of magnetometry far

outweighed any potential cost savings by using that system. The initial brainstorming down

select resulted in two options, Global Positioning Satellite (GPS) system and an inertial

navigation system.

3.2.2.1 GPS System

A GPS system would rely on the standard GPS satellites in orbit above the Earth. This

option would fulfill all of the aforementioned system attributes. Should this system prove to be

the most viable, there exists a wide variety of commercial OEM modules and engines that could

be easily implemented into the overall system design. The size and weight of these modules is

also very low, typically under an ounce and with a maximum linear dimension of two inches.

This system would also fulfill coexisting requirements between our design and the sponsor. GPS

systems adhere to an industry standard, and have standard data outputs that could be easily

manipulated using a microcontroller. The downsides to using a GPS system include the

requirement of external communication with at least one of the GPS satellites in orbit. This, in

turn, would require the use of an external antenna. Also, GPS is limited by obstruction

interference, i.e. foliage and urban environments.

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3.2.2.2 Inertial Navigation System

An inertia system would provide relative positioning based on sensor data from 6-axis

accelerometers and gyros. This system would provide the most accurate measurements on the

position and motion of the plane. The inclusion of accelerometers and gyros allow the option for

a follow-on control system to augment the stability of the aircraft. In contrast with the GPS

system, no external signal is required for the use of this system. There is some error build-up

associated with sensor drift, which may become a problem during extended flight times.

Typically these sensors are also fairly costly. Also implementing a stand-alone inertial guidance

system would add to the overall complexity of the entire system.

3.3 Control

In order to meet the requirements of the project it is necessary to implement a means of

control for the airborne sensing platform. Typically, for hobby plane applications the RC radio

controller is used. Naturally, this became our first concept for implementing a means of control.

In addition to pilot in the loop control, it is possible to implement varying levels of autonomous

control for the airborne sensing platform. This includes customizable levels of pilot and

autonomous function, as well as, full platform autonomy. This autonomous control scheme was

considered as an alternative or complement to piloted control of the airborne sensing platform

3.3.1 Piloted Control

In order to pilot the Airborne Sensing Platform remotely, it is necessary to implement a

radio controller. This radio controller allows the pilot to control the servomotors that actuate the

control surfaces of the aircraft, as well as the throttle. It should also be noted that the radio

controller is a vital component for takeoff and landing scenarios.

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3.3.1.1 Radio Controller

A radio controller is normally classified based upon the number of channels it has and the

frequency it operates on. Radio controllers normally vary between 2 and 9 channels. This

means that the controller has the ability to send signals on 2 to 9 separate pieces of equipment

onboard the aircraft via an onboard receiver. The initial concept was a 4-channel controller to

handle the four servomotors onboard the aircraft, specifically, the ability to actuate the rudder,

elevator, aileron and throttle. However, upon further investigation it was determined that these

four channels would not suffice. In addition to the servos themselves, a channel would be

needed for the speed controller to allow proper speed adjustment. This fact created a need to

consider a 6-channel and 9-channel alternative to the first concept developed. The 6-channel

radio controller increases the amount of controller surfaces that can be actuated. This makes it

possible to implement pilot control over an additional flap and spoiler, in addition to the

previously mentioned control surfaces. The knowledge that we were developing a test platform

for future improvement leads to a concept involving a 9-channel radio controller. This controller

model has the ability to actuate the aforementioned control surfaces, as well as control brakes

and mode-select settings. Also, the extra channels can provide a means of bypassing on board

controls and implementing emergency routines. Commercially available radios exist in all many

channel varieties, however, only controllers with 7 to 9 channels allow for extra pilot comfort

features such as customizable stick control and LCD display.

3.3.2 Partial Autonomous Control Systems

Three different flight control system concepts have been developed. They are listed in

order of complexity, from least complex to most complex. More complex systems must have the

full range of capabilities possessed by less complex systems in order to function.

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3.3.2.1 Digital Servo Controller

The most rudimentary concept is that of the digital servo controller. This system consists

of a single microprocessor, analog-to-digital converter, and supporting components. A digital

servo controller is situated between the command signal receiver and the servos. The primary

function of the system is to apply post processing to the command signal to allow the pilot to

choose from various flight modes, such as air braking, landing and takeoff modes, or thermal

soaring modes. Flight modes will reduce pilot workload, increase control effectiveness, and

reduce operational power requirements. Additional functions may include data recording from

on-board sensors, and rudimentary signal reacquisition routines. Additionally, a servo controller

can be programmed to activate accessories, such as a recovery parachute, retractable landing

gear, or customer determined equipment. This concept will be relatively inexpensive to

implement, and is very simple, but will require some minor programming.

3.3.2.2 Stability Augmentation System

A more advanced implementation of the digital servo controller is a complete stability

augmentation system. The system would be similar to that described in 3.3.2.1, but would

require the addition of inertial sensors, such as rate gyros and accelerometers. An onboard

microcontroller would be used to provide closed-loop feedback based on data collected from the

sensors, effectively actively augmenting the stability of the aircraft. This would greatly reduce

pilot workload, particularly beyond line of sight where aircraft orientation can be difficult to

ascertain. Stability control greatly increases the effectiveness and availability of flight modes,

permitting more robust signal reacquisition and enabling limited autopilot capabilities such as

wing level hold, altitude hold, and heading hold. Flight characteristics of the plane can also be

adjusted in software to match pilot preferences and compensate for drastic changes in sensing

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equipment configuration. The concept will be more difficult to implement than 3.3.2.1, requiring

calibration and installation of inertial sensors, and more careful microcontroller selection to meet

the increased computational load. Programming complexity will be similar to 3.3.2.1, as the

stability algorithm is easy to implement.

3.3.3 Fully Autonomous System

A fully autonomous flight control system would require all of the components of 3.3.2.2

in order to function effectively. Additionally, some method of absolute position referencing

would be required, either magnetometer or GPS based. A fully autonomous system would be

capable of flying to a predetermined set of waypoint coordinates without pilot intervention

except during the takeoff and landing stages of flight. This would free the operator to control

sensing telemetry, and would eliminate control problems beyond line of sight. The autonomous

system could be programmed to return to the operator position upon loss of communications, and

would be capable of a controlled emergency landing if manual landing were not possible. A

fully autonomous system is a significantly greater undertaking than 3.3.2.1 or 3.3.2.2, requiring

much more program code, greater processing capability, more advanced base station software,

and additional sensors. However, fully autonomous systems are readily available from a range

of vendors, often with integrated telemetry subsystems. As with the previous system types, the

on-board flight control systems can be programmed to suit changing customer requirements,

even completely different aerial platforms.

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3.4 Sensor Equipment

Due to the nature of the remote sensing tasks being undertaken by the airborne sensing

platform it is important to implement additional sensor arrays to cover the needs of the sponsor,

as well as permit additional utility for the planned future development of the platform.

3.4.1 Temperature Sensor

A temperature sensor onboard the aircraft is important because the primary use of the

airborne sensing platform is in remote sensing of fires. Because the heat generated from fires

can cause severe damage to both internal and external components it is necessary for the pilot to

be aware of external conditions in real time for the duration of the flight. This assures the

integrity of the internal hardware and allows for emergency landing or evasion maneuvers in the

case of extreme heat caused while flying over the fire.

3.4.2 Pressure Sensor

A pitot-static pressure transducer is an extremely desirable piece of equipment to

implement onboard the airborne sensing platform. The sensor provides a mean to determine

static and dynamic pressures, thus allowing for calculation of platform velocity. This piece of

equipment is also important because it provides a means to trim the airborne sensing platform if

using autonomous navigation software. Also, it is possible to purchase a pitot-static pressure

transducer that measures temperature additionally. This would allow for combined measurement

of pressure and temperature in a compact design envelop.

3.5 Base Station

The base station serves as a platform to manage and monitor the remote sensing platform

test bed. The base station must meet several objectives in order to be successful. The primary

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objective is to receive all communications sent by the remote sensing platform. The second

objective is to provide a Graphical User Interface (GUI) for the pilot, which shows real-time

video of the flight, telemetry data, and system characteristics. Finally, it is desired that the base

station is mobile, in that the components can be easily transported to the launch site.

3.5.1 Base Station Configuration

Coordinating with the sponsor proved to limit the scope of the base station complexity.

For this iteration of the remote sensing platform project, the base station serves only as a test bed

for proof of concept; however, the sponsor did express the desire to incorporate as much

functionality as possible. With this in mind, we decided to concentrate efforts on component

requirements and selection. It is also important to realize that the components of the base station

are driven primarily by the design choices of the remote sensing platform. The required

components of the base station are a laptop or mobile PC setup, RF receivers, RF antenna, and a

power supply. The computer is used to process information and display the information in an

organized manner. One receiver is used to collect telemetry and system data from the remote

platform in the 900 MHz frequency range. The second receiver is used to receive and process

the video feedback from the remote platform, which is also on the 900 MHz frequency range.

To receive the RF waves both receivers incorporate high gain omnidirectional antennas. The

power supply is not an important aspect of the concept development as the sponsor is developing

this along with their base station payload; therefore, we must only worry about stable power for

proof of concept testing.

24

3.5.2 Antenna

The antennas used in the overall communications scheme play a large role in successfully

maintaining an RF link. The combination of transmitter output power and the antenna gain must

provide ample margin to overcome the losses incurred during transmission of RF signals. A

successful link is one that is stable at a linear distance of 2 miles.

3.5.2.1 Antenna Scheme

Several key aspects are considered when determining the appropriate antenna

arrangement. These aspects include, but are not limited to frequency range, marginal beam-

width, radiation pattern, polarization, and gain. The frequency range is 900 MHz for both

communication systems onboard the airborne sensing platform. There are two major obstacles

inherent in this application of long-range aerial vehicle communication system, achieving

enough margin and signal separation. Frequently, long-range applications require directional

antennas to achieve the distance requirements while remaining within FCC regulations; however,

due to the nature of aerial vehicles directional antennas are not as desirable. For this reason the

first design iteration will incorporate high-gain omnidirectional antennas at the base station, with

smaller gain omnidirectional antennas onboard the plane. There are several ways to achieve

signal separation when using multiple transmitters within close proximity to one another. The

first is to use different polarization techniques in antenna selection/design. Omnidirectional

antennas are either vertically or horizontally polarized. The second option to mitigate signal

interference is by channel separation within a given frequency band. Due to the high costs of

horizontally polarized omnidirectional antennas, the chosen method to mitigate the effects of

multiple transmitters is channel separation. In summary, both antenna sets incorporate

omnidirectional vertically polarized 900 MHz antennas.

25

4.0 FEASIBILITY

A trade study evaluated the overall feasibility of the individual components and

subsystems considered during concept development. Then the overall system feasibility of

competing concepts was determined by using a weighted method.

Considering the wide variety of components for our application that are commercially

available, it becomes necessary to employ a method to determine which components would be

better for our use than others. By giving weights to various component parameters and

specifications, and then placing ratings or grades based on that particular component’s

performance in that category, a component’s overall rating can be assessed. In our concept

development, subsystem attributes were defined based on the requirements of that particular

subsystem. The team identified the attribute weighting factors, typically with the weight of the

component and power consumption as two of the major factors. Some of these attributes are

pertinent to all or the majority of the components identified for selections, some are specific to

that individual component. Component specifications and data were collected and given a grade.

A 1-3-9 grading scale was used, with 1 being the worst, 3 being baseline, and 9 being the best.

The use of this scale typically better defines the component best suited to the application, and

removes some of the associated ambiguity from the trade study. This rating scale and trade

study method is employed by systems engineers at Boeing Satellite Systems.

4.1 Communication

A communication system is necessary to meet the requirements of the project and to

allow the exchange of telemetry, instrument, and control data between the base station and

platform. A trade study conducted on various communication concepts revealed the most viable

options for the team given cost, schedule and project requirements.

26

4.1.1 Wireless Communication

Once the team determined what frequency range to use for RF communications, the team

performed a trade study on possible communication system architectures that would best meet

the design requirements. The two feasible architectures studied were (1) a dedicated transmitter

for video feedback and a separate telemetry system, and (2) combining the telemetry system and

video feedback system by utilizing the audio channel on a video transmitter. From the trade

study the team determined the best system incorporated a 900 MHz audio/video transmitter

(embedded in the platform), a 900 MHz audio/video receiver (at the base station), and a surface

mount global positioning system (GPS) encoder. See Figure 4 below. This option had lower

power consumption, size, weight and cost. Also, it would have less interference potential due to

fewer radios on-board the aircraft. The range of the transmitter/receiver combination is mainly

driven by the antennas used, output power, path loss, and any interference. By incorporating the

appropriate RF components, the system is expected to exceed the range requirement of two

miles, while remaining within the allowable power consumption, size, and weight limitations of

the aircraft. Numerous vendors offer audio/video transmitters and receiver systems that utilize

the NTSC standard output of a video camera. The system does not require that sound feedback

be provided to the base station; however, the audio channel of the transmitter can be used as a

medium for our telemetry system. The Tiny Track Surface Mount (TTSMT) GPS encoder

offered by Byonics, allows the telemetry information to be encoded on the audio channel of the

transmitter. The telemetry data is decoded at the base station utilizing a standard sound card and

a software package such as AGW Packet Engine (AGWPE).

27

Concept:

RF Aux Compon (ant,amp,etc) & S/W RF Aux Compon (ant,amp,etc) & S/W RF Aux Compon (ant,amp,etc) & S/W RF Aux Compon (ant,amp,etc) & S/WAttribute % Value Score Result Value Score Result Value Score Result Value Score Result

Size (on plane) 10% 1.6x2.825x.7 3 0.3 1.6x2.825x.3 3 0.3 2.6x1.8x.38 3 0.3 2.6x1.8x.2 3 0.3Power (on plane) 25% 3.75 W 1 0.25 3.1 W 3 0.75 3.75 1 0.25 3.1 3 0.75

Cost 10% 540.00$ 1 0.1 295.00$ 3 0.3 640.00$ 0 0 330.00$ 3 0.3Range 20% Medium-High 3 0.6 Medium-High 3 0.6 Medium 1 0.2 Medium 1 0.2

Interface 5% RCA,DB9 9 0.45 RCA, I/O Pins 9 0.45 RCA,DB9 9 0.45 RCA,Pin 9 0.45Weight (on plane) 10% 1.47oz 3 0.3 0.67 9 0.9 3.6 3 0.3 3 3 0.3

Resolution 10% 400+ lines 9 0.9 400+ lines 9 0.9 400+ 9 0.9 400+ Lines 9 0.9Data Throughput 5% 19kbps 3 0.15 ~ 300 baud 1 0.05 19kbps 3 0.15 ~ 300 baud 3 0.15Channel Capacity 5% 1, 7 1 0.05 1 3 0.15 4,7 3 0.15 4 3 0.15

Total 100% 3.1 4.4 2.7 3.5

DOES NOT INCLUDE:

900 MHz - (2) Comm Systems: Data & Video

Video Transmitter: TX-9500 Video Reciever: RX-900

Data Tranmistter: 9Xstream OEM Description:

900 MHz - (1) Comm System: Data & Video

Video Transmitter: TX-9500 Video Reciever: RX-900

Tiny Track SMT GPS Ecnocder

DOES NOT INCLUDE:

Data Reciever: 9Xstream OEM Data Reciever: 24Xstream OEM

DOES NOT INCLUDE:

2.4 GHz - (2) Comm Systems: Data & Video

Video Transmitter: THX-2450Video Reciever: RX-2400

RF Module

DOES NOT INCLUDE:

2.4 GHz - (1) Comm System: Data & Video

Video Transmitter: THX-2450Video Reciever: RX-2400

Tiny Track SMT GPS Ecnocder

Figure 4: Table of Communication Systems Trade Study Results

4.2 Guidance and Telemetry System

The concept development yielded several potential concepts for a means of implementing

platform guidance. As a result, a trade study was conducted to determine the best means of

platform guidance.

4.2.1 Vision Guidance System

4.2.1.1 Camera Packaging Scheme

Video cameras are available as a camera-transmitter package or as a camera only. A

camera that is separate from the transmitter is more practical for the airborne sensing platform

because a camera without a transmitter weighs less and provides more flexibility in the design

and implementation of a vision guidance system. Another transmitter is available on the

28

platform as part of the telemetry system, so the team will reduce the overall system weight and

power consumption by selecting a stand-alone camera unit and integrating it with the existing

transmitter.

4.2.1.2 Camera Selection

Video cameras are available with CCD or CMOS imagers. The fact that CCD cameras

provide superior image quality while having the same power consumption as CMOS cameras

made them the ideal choice for this platform. Other camera attributes are also important

considerations in addition to the type of imager.

Camera units are commercially available with a large array of attributes. The major

attributes included in the trade study were effective pixels, minimum illumination, cost, power,

video output, weight, horizontal resolution, dimensions, audio capability, color, and signal

system.

Power, resolution, and the presence of an audio channel were given the greatest weight in

the feasibility assessment because they drive the success of this project. Resolution determines

image quality and the associated power consumption. Also an audio channel may be necessary

to transmit telemetry data.

Figure 5 contains the results of the trade study. Our top choice camera is the Mini B/W

Camera w/Audio (VC-210B-AUDIO) from Circuit Specialists Inc. This model has low power

consumption, high resolution, audio capabilities, and can operate in minimal illumination. In

addition, the camera’s 1.0 Vp-p, 75 Ohm video output integrates well with our communication

system.

29

Concept:

Attribute % Value Score Result Value Score Result Value Score Result Value Score Result

Effective Pixels 5% 510x492 3 0.15 512x492 3 0.15 510x492 3 0.15 510x492 3 0.15Min. illum. (LUX) 10% .05 LUX 9 0.9 0.5 LUX 3 0.3 1.0 LUX 1 0.1 .05 LUX 9 0.9

Cost 10% $34.50 3 0.3 3 0.3 $54.50 3 0.3 $33.00 3 0.3Power 15% 1.08 W 9 1.35 1.8 W 1 0.15 1.44 W 3 0.45 1.2 W 9 1.35

Video Output 5% 1.0Vp-p 75 Ohm 9 0.45

1.0Vp-p 75 Ohm BNC / F

connector9 0.45 1.0Vp-p 75

Ohm 9 0.45 1.0Vp-p 75 Ohm 9 0.45

Weight (on plane) 3 0 9 0 3 0 3 0Horizontal Resolution 15% 420TV Lines 9 1.35 330 TV lines 9 1.35 380 TV lines 9 1.35 420 TV lines 9 1.35

Dimension 10%30.8mm x 30.8mm x

15mm3 0.3 3 0.3

36mm x 36mm x 20.5mm

3 0.3 38mm x 38mm 3 0.3

Audio 20% YES 9 1.8 YES 9 1.8 YES 9 1.8 NO 1 0.2BW/Color 10% BW 1 0.1 Color 1 0.1 Color 1 0.1 BW 1 0.1Package Case Case Board

Signal System EIA (NTSC) NTSC NTSC EIA (NTSC)

Total 100% 6.7 4.9 5 5.1

Mini B/W Camera w/Audio Color DSP Mini CCD w/audio SONY Super HAD CCD mini w/Audio SONY Super HAD CCD mini

Description DOES NOT INCLUDE: DOES NOT INCLUDE: DOES NOT INCLUDE: DOES NOT INCLUDE:

Figure 5: Table of Camera Selection Trade Study Results

4.2.2 GPS

GPS engines and modules are fairly standard across the industry. The majority of the

engines is based on the same two or three chipsets, and subsequently has very similar

characteristics.

For our evaluation, the team identified several parameters as being pertinent to our

system requirements. Accurate position and velocity measurements would assist the pilot in

adhering to the mission route. With the length of the flight time, the design is also restricted on

component weight and power consumption. Size also is a factor because there is a limited

amount of space for the payload bay. The sampling size affects the data throughput for the

30

communication system. The cost of the unit, acquisition time, and dynamics under which the

unit can properly operate also played a factor in the evaluation. The data transmission scheme or

interface will also have an effect on the overall system architecture. And finally, operating

temperature was also given consideration due to the fact that temperatures over a fire may be

extreme.

Several different units manufactured by several different companies were considered.

The results are tabulated below. One of the units manufactured by Royal Tech (REB3300)

available at Mobile GPS Online was selected as the best component for use.

GPSWeighting

Factor Value Utility Util*Wt Value Utility Util*Wt Value Utility Util*WtPos/Vel Accuracy 0.1 10 m, 0.1 m/s 9 0.9 15m, 0.05 m/s 3 0.3 25 m, 0.1m/s 1 0.1

Weight 0.1 0.12 oz 9 0.9 0.35 oz 3 0.3 0Sampling (pulse) 0.05 1 s 3 0.15 1 s 3 0.15 1 s 3 0.15Operating Temp. 0.1 -40 to 85 C 9 0.9 -30 to 85 C 9 0.9 -10 to 70 C 3 0.3

Size 0.1 1x1x0.12" 9 0.9 0.94x1.69x0.309" 3 0.3 1.18x1.57x0.28" 3 0.3Cost 0.1 $70 3 0.3 0 $75 3 0.3

Acquisition Time 0.05 38 s 3 0.15 15 s (warm) 9 0.45 38 s (warm) 3 0.15Dynamics 0.15 0 514 m/s, 6g's 9 1.35 515m/s, 4g's 3 0.45

Power 0.2 0.215 W 9 1.8 0.2805 W 9 1.8 0.165 W 9 1.8Interface 0.05 0 CMOS 1 0.05 serial (opt RS-232) 9 0.45

1 sum 6 sum 5.6 sum 4

MGO - REB3300 Garmin GPS 15 Laipac TF-30

Figure 6: Table of GPS Trade Study Results

4.3 Control

The feasibility of various control options was again considered via a trade study. The

main areas of feasibility were concentrated around ways to implement piloted control,

autonomous function, and fully autonomous flight.

31

4.3.1 Radio Control

In order to provide a means for take off, landing, and in flight control of the aircraft a

radio controller is needed. A feasibility trade study was conducted on various types of

controllers that were commercially available. The main attribute that drives controller selection

is the number of channels available to the pilot for actuating control surfaces. Also the degree of

customization that can be done to the controller to provide pilot comfort is important. For ease

of comparison, only Futaba brand controllers were evaluated. Futaba provides a detailed list of

features that are industry standard and are widely used for this application. At this time, there is

a need for at least four channels to control the actuation of the elevator, rudder, ailerons, and

throttle. However, additional control surfaces may be added. Because it is a development

platform, it is necessary to consider controllers with higher channel capabilities. The sponsor

expressed interest in the Futaba 9-channel receiver, and upon further research, it was found to

provide a wide variety of features for pilot comfort and customization. When coupled with a 9-

channel receiver on board it will provide the ability to control the platform control surfaces up to

the range requirement for the project. However, if interference becomes an issue the controller

signal can be amplified to meet the requirement.

Concept:

Attribute % Value Score Result Value Score Result Value Score Result Value Score Result

Size Receiver (on plane) 10% 2.52x1.39x0.82 in^3 3 0.3 2.52x1.39x0.82 in^3 3 0.3 1.3x 2.1x0.8 in^3 3 0.3 Not Specified 3 0.3Power (on plane) 20% 600 1000 mAh 3 0.6 600 1000 mAh 3 0.6 600 1000 1500 mAh 3 0.6 Not Specified 1 0.2

Cost (Radio) & Cost Receiver) 10% 250 + 60 3 0.3 300 + 60 3 0.3 350 + 130 3 0.3 2200 + 1 0.1Customizing 10% Medium 3 0.3 Medium 3 0.3 High 9 0.9 Very High 9 0.9

Range 20% High 3 0.6 High 3 0.6 High 3 0.6 High 3 0.6Weight Receiver (on plane) 10% 1.5 oz 3 0.3 1.5 oz 3 0.3 1.25 oz 3 0.3 3 oz 3 0.3

Channel Capacity 20% 6 1 0.2 7 3 0.6 9 9 1.8 14 9 1.8Frequency 72 MHz 0 72MHz 0 72MHz 0 72MHz 0

Total 100% 2.6 3 4.8 4.2

6 Ch. 7 Ch. 9 Ch. 14 Ch.

Description:

Futaba Futaba Futaba Futaba6 Channel suited for RC plane 7 Channel suited for RC plane 9 Channel suited for RC plane 7 Channel suited for RC plane

standard 7 channel w/o crystal standard 7 channel w/o crystal standard 9 channel no crystal req.standard 14 channel no crystal req.

DOES NOT INCLUDE: DOES NOT INCLUDE: DOES NOT INCLUDE: DOES NOT INCLUDE:

32

Figure 7: Table of Radio Controller Trade Study Results

4.3.2 Partially Autonomous Control System

Initially there were several competing concepts for partially autonomous control systems

for the airborne sensing platform. The concepts were a simple micro controller, stability

augmentation, and a fully autonomous sensor package. A trade study was conducted among

these concepts to determine the most feasible in each category.

4.3.2.1 Digital Servo Control

The digital servo controller provided a relatively inexpensive means of implanting

autonomous flight routines. However, it would require excessive time to program, debug and

integrate into the overall system. The main time consuming tasks would be interfacing between

the transmitters and telemetry equipment, and the creation and incorporation of the associated

control algorithms needed to maintain autonomous function.

4.3.2.2 Stability Augmentation System

In order to determine the best means for implementing a stability augmentation system, a

number of different commercially available sensor packages were evaluated. The desire to

produce an airborne sensing platform with as much customization as possible drove the selection

process. Important factors were telemetry features and range, as well as cost. The full stability

augmentation system would require the selected sensor package and additional control

algorithms executed by a microcontroller to create a means of servo control based on feedback

from the sensor package. This adds a great deal of complexity to the system, as it would involve

33

a great deal of time and programming to link all the onboard components. See Figure 8 below

for a summary of the sensor package trade study.

Concept:

Attribute % Value Score Result Value Score Result Value Score Result Value Score Result

Cost 20% 2590 3 0.6 250 9 1.8 225 9 1.8 80 9 1.8Axes 10% 6 9 0.9 5 3 0.3 4 3 0.3 3 1 0.1

Sensors 20% 3 Accel,3 Gyro,3 Magneto 9 1.8 2 Accel, 3 Gyro 3 0.6 2 Accel, 2 Gyro 3 0.6 3 Magneto 1 0.2CEP (Pos.) 10% 2m 9 0.9 NA 1 0.1 NA 1 0.1 NA 1 0.1CEP (Rel.) 10% 20cm 9 0.9 ? 1 0.1 NA 1 0.1 NA 1 0.1

Angular Rate 0% 90 deg/sec 3 0 90 deg/sec 3 0 90 deg/sec 3 0 ? 1 0Accel. Rate 0% 19.6 m/s^2 3 0 19.6 m/s^2 3 0 19.6 m/s^2 3 0 NA 1 0

Angular Prec. 0% 0.5-1 deg 3 0 0.5-1 deg 3 0 0.5-1 deg 3 0 ? 1 0Refresh 10% 200Hz 3 0.3 ? 3 0.3 ? 3 0.3 ? 3 0.3Power 15% 2.5W 3 0.45 ? 9 1.35 ? 3 0.45 ? 9 1.35

Interface 5% Ethernet 10/100T 3 0.15 RS232 9 0.45 RS232 9 0.45 8-bit SPI 3 0.15Notes: Inc. Servo Controller Inc. Servo Controller w/Servo Controller

Total 100% 6 5 4.1 4.1

5DOFIMU

Rotomotion

AHRS200ADescription: 4DOFIMU 2.4 3-Axis Magnetometer

Rotomotion RotomotionRotomotion

Figure 8: Table of Stability Augmentation System Trade Study Results

4.3.2.3 Fully Autonomous System

Another concept that was proposed was a fully functional autonomous navigation system.

Important factors were telemetry features and range, as well as cost and availability of base

station software packages. Also the ability to allow piloted control for take off and landing was

extremely important because it is nearly impossible to achieve smooth take off and landing using

only a commercially available autonomous sensor package. The best fully autonomous stability

augmentation system was the AP50 Autopilot. This system exceeded the range requirements and

provided a means to acquire both GPS and inertial information in a compact, lightweight design

envelope. The Autopilot also included extra A/D channels that can be used to transmit video or

other sensor information from onboard the Airborne Sensing Platform to the base station. The

Autopilot also comes with base station software that permits the pilot to track the flight path of

34

the platform and add additional waypoints during a mission. Although a fully autonomous

system is comprised of a more complex design, it provides a larger array of options for the

sponsor to modify or upgrade in the future. The commercial availability of the system limits

design and programming time on individual components allowing increased time to consider

system integration and configuration concerns. See Figure 9 for a summary of the fully

autonomous systems trade study.

Concept:

Attribute % Value Score Result Value Score Result Value Score Result Value Score Result

Cost 10% 5000 3 0.3 800 9 0.9 5000 3 0.3 ~4000 3 0.3

Telemetry 20%RS485 900MHz, 7 mile range (also avail. Seperately) 9

1.8RS485 900MHz, 7mi range

(not included (add $550)), 40 mile also avail.

3 0.6 Capable (std. 2.4 GHz wireless modem) 1 0.2 900 MHz Maxtream

Transeiver 15 miles range 9 1.8

Autonomy 10% Full (w/o ATOL) 9 0.9 Partial 3 0.3 Partial 3 0.3 Full (w/o ATOL) 9 0.9

Manual Mode 5% YES 3 0.15 YES 3 0.15 YES 3 0.15 YES 3 0.15Video 10% Not Included 1 0.1 Capable 3 0.3 NTSC w/GPS overlay 9 0.9 capable thru A/D? 3 0.3

Sensors 10% 6 axis inertial, GPS capable, pitot, baro.

3

0.3 GPS capable, SMT Baro., 2-axis inertial 1 0.1 DGPS, 6 axis inertial,

airspeed, alt. (ultrasound)9

0.93 rate gyros, 2 axis accel.

,Altimeter, Airspeed: designed to connect to pitot

3 0.3

Basestation 10% YES, TRACKER software 3 0.3 YES, TRACKER software 3 0.3 YES, HORIZON software 3 0.3 YES, GroudPilot Software 3 0.3Size 5% 4 x 2 x 1.6 in 3 0.15 1 x 2 x 0.5 in 9 0.45 10 x 4 x 2 cm 3 0.15 5.7x1.9x1.1 in 3 0.15

Weight 5% 3 oz 3 0.15 57 g or 2 oz 3 0.15 28 g or 1 oz 9 0.45 50g or 1.76 oz 3 0.15Power 10% 5-14 V @ 180mA 3 0.3 5-7 V @ 50mA 3 0.3 6.5 V @ 140 mA 3 0.3 5.4-8 V @ 120 mA 3 0.3

Waypoints: 5% 16 1 0.05 32 3 0.15 1000+ 9 0.45 24 add / change during flight 3 0.15Notes 2 extra A/D for other sensors

Total 100% 4.5 3.7 4.4 4.8

UNAV3300 PICO-PILOT MP2028 AutoPilot 50

UAV Systems

DescriptionAutonomous Packages Autonomous Packages Autonomous Packages Autonomous Packages

U-NAV U-NAV Micropilot

Figure 9: Table of Autonomous Systems Trade Study Results

4.3 System Level Feasibility

In preparation for the sponsor concept design review, the team completed a trade study

on the various component concepts. The results allowed the team to narrow down the best

35

options for individual components and subsystems and present them to the Center of Imaging

Science. This information was then used to create three competing concepts for an overall

system that would provide the sponsor with an airborne sensing platform that met or exceeded all

the objectives and specifications of the project. These system concepts were: piloted control,

piloted and autonomous control, and a complete commercially available UAV system that

included the platform and telemetry components. After the three system level concepts were

developed, a feasibility analysis was performed using a weighted feasibility method. Driving

factors were sponsor requirements, cost, weight, and time considerations based on complexity

and resource availability. Due to the limited nature of the commercially purchased system

configuration, it scored low in the feasibility analysis. See Figure 10 for a complete review of a

system level feasibility study.

36

Figure 10: Table of System Level Feasibility Study

4.3.1 Piloted Control

This system level design incorporates an RF communication system comprised of a

Futaba radio controller and receiver pair. This allows for piloted control of the airborne sensing

platform. The pilot handles take off and landing maneuvers and guides the plane to the target

location. The platform incorporates the video camera and GPS systems previously mentioned.

The GPS signal is encoded via the Tiny Track and sent down to the base station over the audio

channel provided by the video camera. This system provides the navigational cues necessary to

fly the plane at long distances because the pilot has location and velocity information from the

GPS and stability cues such as the horizon from the real time video feedback. This system

configuration is the least expensive option and the easiest to implement, however, it provides

limited capabilities and less customization. Also, pilot work load is high due to the potential for

long range missions.

4.3.2 Autonomous Control Capability

The proposed system utilizing autonomous control capability provides a means for both

pilot in the loop and autonomous control of the airborne sensing platform. The system would

still implement a Futaba radio controller and receiver pair, however this would utilized only for

take off and landing scenarios and the avoidance of situations detrimental to the integrity of the

platform. It is important to maintain piloted capabilities because commercially available

autonomous systems cannot provide an accurate means for take off and landing. It is also

necessary to maintain some level of piloted control during adverse conditions that may be

created by the fire such as thermal updrafts and shifting winds. A much more serious condition

37

known as flashover may also occur. Flashover is a condition in which the air above a fire

combusts. A fire may begin to die down with an expiring oxygen supply; however, a sudden

wind gust can provide a new supply which causes the fire to suddenly flare up. In these

situations, the pilot can take control of the aircraft and safely navigate the platform away from a

potentially harmful situation.

The autonomous capability is implemented with the AP50 AutoPilot hardware and

GroundPilot software at the base station. The AP50 AutoPilot has both GPS and inertial

guidance capabilities. It also incorporates a long-range transceiver to provide a means of

communication between the base station and the airborne sensing platform. Another appealing

feature of the AutoPilot system is extra open A/D channels allowing the team and or sponsor to

transmit data from additional sensors onboard the plane. This system configuration will also

incorporate a vision guidance system. This system will be comprised of a small CCD video

camera connected to a wireless modem. It will provide real time feedback to the pilot to aid in

piloted flight and alert the pilot to potential problems during a mission. The camera chosen has

an available audio channel. This provides the sponsor a means to send down GPS or other

encoded data in the future. Although this is a somewhat redundant system, it provides the

sponsor with maximum flexibility in customizing and upgrading the system in the future. It is

important to note that this system, while more expensive than the system previously mentioned,

can still be implemented under the given budgetary constraints. The lightweight and small size

of all the aforementioned components allow the team to meet the requirements for endurance and

loiter, while providing maximum capability and flexibility to the sponsor. Not surprisingly, this

option scored the highest in the feasibility analysis. See Figure 10.

38

4.3.3 Commercially Available Complete System Solutions

The Micropilot MPUAV was selected as the best complete UAV system from among

competing vendors that met basic sponsor specifications. Driving factors in the decision were the

low cost when compared with other systems, commercial availability of base station equipment,

and the ability to store a large numbers of programmable waypoints. However, this system

concept was extremely expensive and could not be customized to the degree necessary to provide

a quality durable airborne sensing platform test bed. This is apparent from its lower score in the

feasibility analysis.

4.4 Overall System Selection

The team in conjunction with the sponsor has elected to implement a design that allows

for both piloted and autonomous control of the airborne sensing platform. The platform will use

the AP50 AutoPilot to provide GPS and inertial data to the base station. The AP50 will also

provide the means of autonomous navigation when combined with a pitot-static tube and the

GroundPilot software package at the base station. The team will implement a vision guidance

system that consists of a camera and receiver/transmitter pair that is separate from the long-range

radios on the AP50 autopilot. Also a temperature sensor will be placed onboard the platform to

provide additional feedback to the pilot about the ambient conditions around the platform. This

data will be transmitted on the additional A/D channels of the AP50 AutoPilot.

5.0 OBJECTIVES AND SPECIFICATIONS

The team in conjunction with the Center for Imaging Science developed a set of

guidelines, performance specifications, and design objectives. These were used in order to

39

assess the successfulness of the project. This section will discuss these guidelines, performance

specifications and design objectives as agreed upon by the team and the sponsor.

5.1 Performance Specifications

1) The platform shall loiter long enough for remote sensing tasks to be executed by

the Center for Imaging Science. Based on sponsor input a flight duration time of

1 hour will allow the pilot to complete remote sensing tasks.

2) The platform must have the ability to fly autonomously or via piloted control to

altitudes at or below 1,000 ft.

3) The platform must have the ability to fly autonomously or via piloted control to

distances of 2 miles away from the base station.

4) The platform shall cruise at a range of speed between 15-25mph.

5) The platform must be able to carry a 3 lb modular payload designated by the

Center for Imaging Science.

5.2 Design and Implementation Specifications

5.2.1 Platform Durability

The platform airframe must be able to withstand takeoff and landing loading conditions.

The platform should be constructed to allow for multiple remote sensing missions. The vision

guidance system and telemetry should be protected from shock due to take off and landing.

40

5.2.2 Fuselage

5.2.2.1 Fuselage Interior Payload

The fuselage must be capable of holding the Center for Imaging Science payload and the

onboard vision guidance equipment and telemetry. Measures should be taken in mounting

onboard equipment to allow easy access to vision guidance and telemetry system, as well as CIS

payload. Consideration should be given to future development of platform and allow mounting

space for additional equipment and sensors. The fuselage must provide a means by which to

protect equipment for heat exposure during remote sensing tasks.

5.2.2.2 Fuselage Exterior Payload

The fuselage must be capable of mounting exterior sensor equipment safely and easily.

The fuselage must provide a means by which to protect equipment for heat exposure during

remote sensing tasks.

5.2.3 Dimension

The overall size of the platform will be minimized to allow cost and weight savings.

However, this act shall not compromise the performance goals previously set forth.

5.3 Stability and Control

The pilot must be able to adequately control the platform in a manner that allows for

successful completion of remote sensing tasks.

5.3.1 Control Surfaces

The control surfaces on the platform will provide the pilot with the ability to navigate.

41

There shall be enough dynamic control surface available for the pilot to perform aerial

maneuvers associated with remote sensing tasks. The static surfaces on the platform will also be

designed to improve overall stability. Overall, the platform shall be designed to be passively

stable.

5.4 Electrical Systems

5.4.1 Video

The platform will utilize a camera as part of a vision guidance system. The camera

system will transmit a real time video signal back to the base station. This will give the pilot the

ability to carry out remote sensing tasks when the platform is out of visual range. The conditions

under which the camera is operating should be considered to be ambient light on a sunny day.

5.4.2 Global Positioning System (GPS)

A GPS system onboard the platform will send back navigational information to the base

station. From this GPS data, the pilot will know altitude and distance from the base station. It

will also serve the purpose of locating remote sensing targets. In the event of a crash, the GPS

will aid in faster retrieval of the platform. Also the GPS should aid in panic mode if the plane

loses the control signal. The GPS system should be implemented in a way that allows the Center

for Imaging Science to utilize GPS information for their payload.

5.4.3 Transceiver

The platform will utilize an RF communication scheme to send and receive data. The

pilot will transmit a control signal from the base station. A receiver onboard the platform will

then use that control signal to actuate the dynamic control surfaces on the platform. A

42

transmitter will send data from the navigation and GPS systems to the base station. A receiver at

the base station will then utilize the streaming data to give the pilot real time feedback about the

platform.

5.4.4 Base Station

The base station will provide the pilot with the necessary navigational cues to assist in

flying the platform when it is no longer in sight. It shall provide a means of displaying the

streaming video and GPS signal. The base station should provide the pilot with information

about power consumption on board the platform. The base station should assist in signal

processing on the control signal. The base station should be durable enough to complete

multiple remote sensing tasks. The base station should be portable.

5.4.5 Batteries

The power plant onboard must supply sufficient power to run the vision guidance and

telemetry systems, as well as additional sensors to be determined. Also the batteries must

provide enough power to actuate the dynamic control surfaces and power the motor in

accordance with the previously outlined specifications. The battery must be rechargeable to

accommodate multiple remote sensing missions. The battery should be chosen to maximize

power while minimizing weight.

5.4.6 Possible Platform Features

Additional features may be added to the platform to increase its utility. These features

are dependent on cost, time, and skill set. Their feasibility will be considered throughout the

project based on analysis and synthesis work done for the project and may be implemented on

the final design of the Airborne Sensing Platform.

43

5.4.6.1 Inertial Navigation

A set of rate gyros would allow a greater degree of controllability for the pilot. Also, it would

allow for autonomous or semi-autonomous flight if implemented with a stability augmentation

system. At this time, the team plans to implement an inertial navigation system as part of the

AP50 AutoPilot hardware.

5.4.6.2 Stability Augmentation System

A stability augmentation either commercially available or custom made would provide a

feedback control loop for the Airborne Sensing Platform. This would allow of semi-autonomous

or autonomous flight. At this time, the team will implement a stability augmentation system via

the AP50 Autopilot hardware. This system uses imbedded control algorithms and sensor inputs

from GPS and inertial systems to provide pilot out of the loop control of the platform.

5.4.6.3 Flight Control and Recovery Systems

An algorithm for implementing emergency landing procedures may be implemented to

allow for ease of recovery of the platform in the event of communication loss with platform. In

the event of signal loss from the base station, the AP50 hardware previously mentioned provides

circling flight routines that allow for signal recovery or emergency landing.

5.4.6.4 Onboard Temperature Sensor

Due to the sensitive nature of the remote sensing equipment, hot updrafts from a fire

could cause damage to the platform. A temperature sensor onboard the platform would aid the

pilot in determining if conditions are unfavorable for flight over a fire. At this time, the team

plans to implement a temperature sensor onboard.

44

5.4.6.5 Onboard Pressure Sensor

A pressure transducer accompanied by a pitot-static tube attached to the exterior of the

Airborne Sensing Platform will allow for dynamic and static measurements of pressure while the

platform is in flight. This will enable measurement of ambient conditions through which the

platform is flying. It also allows for the determination of local velocity. The AP50 AutoPilot

has a temperature compensated integrated silicon pressure sensor. The team will construct a

pitot-static tube and combine it with the pressure sensor to provide pressure information and

velocity measurement.

5.4.7 Controller

The controller must be able to transmit a control signal to the platform either stand-alone

or with the aid of the base station based upon previously stated requirements. The controller

must be capable of actuating at least four control surfaces. The controller should be easy for the

pilot to learn and operate.

5.4.8 Controller Receiver

The receiver must be capable of receiving control signal from controller. The receiver

must be able to control at least four control surfaces. The receiver should minimize size and

weight in accordance with previous requirements.

5.4.9 Onboard Processing

Utilizing a programmable integrated circuit (PIC) or digital signal processing (DSP) chip

will allow the platform to store GPS and other data to aid in logical decision making for control

purposes. The PIC or DSP chip should allow the platform to actuate the control surfaces in the

event of control signal loss. The chip should allow for semi-autonomous control option. The

45

chip should also include a sufficient means of data storage and processing onboard to aid in

flight control and recovery.

5.5 Design Practices

In order to accomplish the design objectives and specifications the team utilized the

following list of design practices as a guide throughout the design process.

1) Design for Manufacturability – The platform and subsystems should be designed

with components that are readily available or relatively easy for someone

unfamiliar with the project to machine. This ensures the sponsor will be able to

maintain a viable platform after the senior design team turns the prototype of to

the Center for Imaging Science.

2) Design for Assembly – The platform is intended to be a development platform.

As such, it will be assembled, disassembled, and modified frequently. The design

must allow ease of access to cargo bays. Also issues surrounding fatigue failure

and wear on components due to assembly and disassembly should be addressed.

3) Design for Reliability – The platform and subsystems should be reliable enough

to allow for multiple flights. It is common to have minor failures on platforms of

this type; however, major subsystems should be designed to provide impact

resistance to ensure the longevity of the components.

4) Design for Accuracy – The mounting systems within the fuselage and the other

platform components should have a tolerance that provides minimal error to allow

ease of replacement.

46

5) Design for Safety – The platform design should consider safety to the pilot during

launch and landing, as well as FCC and FAA guidelines for operating platforms

of this type.

5.6 Safety Issues

The team should consider both FCC and FAA regulations and licensing requirements as

they pertain to Unmanned Aerial Vehicles when considering electrical and mechanical

components for the platform. However, due to the nature of the missions to be carried out by the

Airborne Sensing Platform, no emphasis shall be placed on these regulations at this time. Also,

the design of individual components should consider ergonomics. Removing sharp corners and

providing ease of assembly will reduce the potential for accidents and injuries related to

repetitious activities.

5.7 Launch

A means of launching the platform must be accomplished. The launch should not

damage any equipment onboard the Airborne Sensing platform. At this time, the team plans to

use either hand launching or a winch launch system.

5.8 Pilot

A pilot will be needed to provide take of and landing for the Airborne Sensing Platform

in order to complete remote sensing tasks. The pilot should have an AMA license and

knowledge of RC planes.

47

5.9 Deliverables

1) Preliminary Concept Review (January, 2005) – This was completed during the

month of January. It includes a presentation and brainstorming session with the

sponsor to determine concept and feasibility for features on the Airborne Sensing

Platform.

2) Preliminary Design Review (February, 2005) – This will be completed at the end

of Senior Design 1. It includes a written report and a formal presentation on the

progress completed by the Senior Design Team

3) Airframe Completed (February, 2005) – The current Senior Design 2 team 05008

will complete and demonstrate a working RC plane at the end of Winter Quarter

and turn it over to our team in order to complete the necessary upgrades to

complete the Airborne Sensing Platform. If the platform is not ready the team

will construct a plane.

4) Critical Design Review (May, 2005) – This will be completed at the end of Senior

Design 2. It will include a final report and presentation, as well as, a

demonstration of the prototype.

5.10 Overall Period of Performance and Schedule

Start Development – December 2004

PDR – February 2005

CDR – May 2005

48

6.0 DESIGN ANALYSIS AND SYNTHESIS

6.1 Airframe Analysis

In order to evaluate the design of the overall system to be implemented in the airborne

sensing platform it was necessary to analyze the airframe that would carry the telemetry

subsystem, vision guidance subsystem, and other sensor subsystems. This included a dynamic

analysis of the aircraft being produced by the #05008 senior design team, and a performance

analysis of aircraft alternatives.

6.1.1 #05008 Airframe Stability Analyses and Redesign

The #05008 aircraft stability and control characteristics were evaluated in order to ensure

adequate passive stability performance for integration of automatic flight systems and accurate

data acquisition in a high updraft flight envelope. The design presented by the #05008 PDR

document specifies empennage dimensions which result in vertical and horizontal tail volume

coefficients of 0.01 and 0.21, respectively. These values fall below generally accepted criteria

for highly stable flight, and are deficient when compared against the stability properties of

successful RIT Aero Design Heavy Lift planes designed for similar tasks. Software designed for

the RIT Aero Design team shows that the unmodified #05008 will possess a static margin below

7%, which is much too low for sustained flight in turbulent regions.

A least-squares optimization routine coupled with the previously existing RIT Aero

Design software was used to develop new tail volume coefficients for increased stability.

Vertical and horizontal tail volume coefficients of 0.06 and 0.3, respectively, were developed to

ensure stable flight with a static margin of 15 - 20%. The following tail dimensions were

49

recommended to the #05008 design team to reach the desired stability performance with a

minimum of modification to the original design.

bh (horizontal span) = 30”

ch (horizontal chord) = 8”

bv (vertical span) = 15”

cv (mean vertical chord) = 6”

Also computed were new control surface volume coefficients resulting in the dimensions

given below. The control characteristics selected are based on pervious experience design

control surfaces for aircraft of this type, and are confirmed by aeronautics reference texts.

Experience has shown that control surfaces for aircraft of this type must be slightly oversized

compared to full-scale aircraft. This is likely due to a loss in control surface effectiveness due to

low Reynolds number effects and high vortex flow lift loss over short spans.

bξ (aileron span) = 23”

cξ (aileron chord) = 2”

be (elevator span) = 30”

ce (elevator chord) = 2”

br (rudder span) = 15”

cr (rudder chord) = 2.5”

Other attributes that can improve stability with little to no cost of performance or

manufacturing complexity are the addition of main wing dihedral and aileron relocation. The

recommended changes are as follows:

1) Add 3°of dihedral to the main wing. This can also be expressed as a 2.75” rise over the

span from root to tip.

50

2) Relocate the ailerons so they are centered about the 2/3 half-span point. Vortex-induced

tip losses reduce aileron effectiveness when they are placed near the wingtips; however,

this loss of effectiveness is not considered in the standard aileron volume coefficient

formula. This is a misunderstanding which often results in the intuitive placement of the

ailerons at the extreme outboard edge of the wing, reducing their actual effectiveness.

All of the above recommendations were issued to the #05008 design team, and have been

implemented in the aircraft design, as of the publication of this document.

6.1.3 #05008 Airframe Weight Analysis - Cg

Center of gravity calculations were done to determine the ideal location for the wing. The

calculation provides a location for the wing that places the quarter chord of the wing at the center

of gravity of the airframe. All telemetry equipment used by the team along with airframe

components as specified by team #05008 were used to tabulate the theoretical center of gravity

by summing the moments created by the components and the airframe pieces. The Cg of the

quarter chord of the wing was found to be 29.38in. The results are summarized in Appendix B.

This information was then provided to team #05008 to help complete the airframe under

development.

6.1.2 Senior Telemaster Performance Analysis

As an alternative to the #05008 airframe, the Senior Telemaster aircraft design is offered

as a performance enhancing replacement. The Senior Telemaster is a highly affordable

commercially available kit plane designed to lay telecommunications cable between

mountaintops. The design payload is in excess of 40 N, and when coupled with the electric

powerplant from the #05008 aircraft, can be substantially increased. It is well known for its

51

docile handling qualities, and is often used to train radio controlled aircraft pilots. Power and

speed requirements for an aircraft carrying a 45 N payload were tabulated, resulting in plots of

CL3/2 / CD vs. Speed (Fig. 11) and CL / CD vs. Speed (Fig. 12), the local maximums of each

corresponding to the speed for best endurance and best range, respectively. The results of this

analysis are tabulated in Figure 13.

CL3/2/CD at Sea Level and Cruise Condition

0

2

4

6

8

10

12

14

0 5 10 15 20 25 30 35 40

Velocity (m/s)

CL3/

2 /CD

(CL3/2/CD)Max is 12.5

52

Figure 11: Plot of CL3/2 / CD vs. Speed

Lift to Drag Ratio vs. Velocity at Sea Level and Cruise Conditions

0

2

4

6

8

10

12

0 5 10 15 20 25 30 35 40

Velocity (m/s)

CL/

CD

(CL/CD)Max is 10.6.

Figure 12: CL / CD vs. Speed

Range and Endurance Calculations Lowest Power Consumption (W) 71.00Cruise at LPC (m/s) 9.00Stored Energy (W - h) 148.00

53

Endurance (h) 2.08Range at Lowest Consumption (km) 67.54 Best Range Consumption (W) 84.00Cruise at BRC (m/s) 13.00Stored Energy (W - h) 148.00Endurance (h) 1.76Range at BRC (km) 82.46 Energy Expenditure for 300m climb (W - h) 23.00Remaining Energy (W - h) 125.00Minimum Time to Altitude (s) 93.00Endurance at Altitude (h) 1.76

Figure 13: Tabulated results of Telemaster performance analysis

The handling qualities of the Senior Telemaster are well established by its excellent service

record in gusty mountain environments. The tail volume coefficients exceed those of the

redesigned #05008 airframe and a static margin of 20% or more can be achieved, resulting in a

high degree of passive stability. Simulator flight models are also commercially available for the

Senior Telemaster, enabling novice pilots to adapt to the handling qualities of the aircraft without

risking damage to the airframe or other onboard equipment. A speed of 15 m/s is recommended

for takeoff and landing, with estimated minimum runway lengths of 5 and 16 meters,

respectively. Landing field length could be reduced to within 10 meters through the addition of

brakes, if requested by the sponsor.

6.2 Motor Selection and Analysis

The motor and battery were chosen by team #05008 based on there preliminary design

completed during Senior Design I, term 20041. Once the motor and battery arrived, our team

conducted testing on the motor and battery to determine the thrust characteristics and battery life

to confirm the manufactures specifications. In order to test the motor effectively, a sled and

54

force transducer combination was used to determine the static thrust value. A mounting plate

was designed and machined to adapt an existing sled provided by the vibrations lab. This plate

will also allow the team and the sponsor to conduct future tests on the motor and alternate

propellers. From the data gathered in this initial testing phase, the static thrust value was found

to be 4.2 lbs.

6.3 Structural Design and Analysis

6.3.1 Structural Design

The mounting system for the electronics was based on two 2024-T4 aluminum L-

channels with a thickness of 0.1 inches and legs of a length of 0.75 inch. This type of aluminum

was chosen because it is typically used in structural applications. The electronic components

will be mounted on standoffs to aluminum plates of the same material. These plates will be

bolted to each of the rails. This allows alternate placements for the components to modify the

center of gravity of the airframe. It also enables each electronic component package to be

modular. For cross bracing, the two rails will be connected by two plates at each end. Finally,

the whole assembly will be bolted to the bulkheads of the airframe through four L-brackets. An

isometric view of the completed assembly can be seen in Figure 14 below. Detailed drawings

for all of these components can be found in Appendix C.

55

Figure 14: Rail Cage Assembly

56

6.3.2 Structural Analysis

This type of aluminum has a weight density of 0.1 lbs/in3. Adding all of the aluminum

parts, the electronic components, and miscellaneous fasteners resulted in a total assembly weight

of approximately 16 oz, or 1 lb.

PartWeight

(oz) QuantityTotal (oz)

AP50 Autopilot 1.76 1 1.76TX-9500 2.1 1 2.1Rail 2.7 2 5.4Plate (3x6x0.1") 2.9 1 2.9Plate (3x3x0.1") 1.4 1 1.4Plate (3.5x0.75x0.1") 0.4 2 0.8Bracket 0.17 4 0.68Misc. fasteners 0.96 1 0.96

Total 16

Figure 15: Table of total weights

The loading scenario defined for the analysis was a 6G drop. The total force applied will be 6

lbs. This type of loading would be typical in a semi-moderate crash landing. The worst-case

loading scenario on the rail cage itself would be if the total load was borne by a single rail, and it

was applied at the opposite corner of the other rail through a rigid plate. This is a conservative

modeling scenario because in actuality, the load would be borne by both rails and the plates

would also deflect to absorb some of the load. A diagram of this loading is shown in Figure 16

below.

57

Figure 16: Worst-case loading scenario

Using the principle of superposition, this problem can be decoupled into an asymmetric beam

bending and a torsion problem. The results of each can then be added to provide a total solution.

58

Figure 17: Decoupled stress scenario

6.3.2.1 Asymmetric Beam Bending

Asymmetric beams add to the complexity of stress prediction because the cross moments

of inertia are no longer zero. This introduces coupling between the two directions of the cross-

section. The first step in completing this type of analysis is to locate the centroid of the cross-

section. Then the each of the second area moments of inertia can be calculated. For ease of

computation, the cross-section was split into two separate sections as shown in Figure 18 below.

Figure 18: Cross-section dimensions and section divisions

The centroid in the y and z directions can be calculated using the following formulas.

∑ ⋅=i

ii AyA

y 1 ∑ ⋅=i

ii AzA

z 1

Once the centroid has been calculated, the y-z axis can be placed as shown below.

59

Figure 19: Centroid location and axis placement

The second area moments of inertia for each section are then calculated and summed, making

use of the Parallel Axis Theorem when necessary. The Parallel Axis Theorem states that the

moment of inertia about a parallel axis not located through the centroid of the section can be

calculated by the adding the moment of inertia of the section about its own centroid and area of

the section multiplied by the distance to the axis of rotation.

2_ dAII centroidaxisparallel ⋅+=

Typically, bending stresses for symmetric cross sections are calculated using the linear relation

yI

Mx =σ , where

IM

is typically a constant as long as the cross-section remains constant along

the x direction. Since the rail under consideration has a constant cross-section we can assume a

stress field of the following form.

zcycx 21 +=σ (1)

Equilibrium of moments requires that

60

dAzM xy ⋅⋅= ∫ σ(2)

dAyM xz ⋅⋅=− ∫ σ(3)

Substituting Eqn.1 into Eqns. 2 and 3, and making use of the definitions,

∫ ⋅= dAzI y2 ∫ ⋅= dAyI z

2 ∫ ⋅⋅= dAzyI yz

results in the following equations.

yyyz MIcIc =+ 21

zyzz MIcIc −=+ 21

Solving for c1 and c2,

( ) zyyz

yzyzy

IIIIMIM

c−

−= 21

( ) zyyz

zyyzz

IIIIMIM

c−

−−= 22

In order to locate the maximum stress locations, it is necessary to determine the neutral axis of

the beam. The neutral axis is defined as the axis along which bending stresses are zero. In this

situation,

021 =+ zcyc

Rearranging,

61

yzzzy

yzyzy

IMIMIMIM

cc

yz

++

==−

= βtan2

1 .

Solving for β,

yzzzy

yzyzy

IMIMIMIM

++

= −1tanβ

The values for the constants defined by the above formulas appear in Figure 20 below.

224.0=y in224.0=z in00725.0=yI in4

00725.0=zI in4

00424.0=yzI in4

0=yM72=zM in-lbs150931 −=c

88272 =c lbs/in3

°= 6.59β

Figure 20: Table of calculated values

Showing the angle β on the cross-section of the beam reveals that points A and B are the furthest

from the neutral axis (Figure 21).

Figure 21: Location of neutral axis

62

Given the orientation of the moment, this implies that point A has the maximum compressive

stress and point B has the maximum tensile load. Point A has the coordinates (y,z) = (0.526,

-0.224) and point B has the coordinates (y,z) = (-0.224, 0.526). Substituting the above tabulated

values and the coordinates into Eqn. 1 results in a maximum compressive stress at point A of

9916 psi and a maximum tensile stress at point B of 8024 psi.

6.2.3.2 Transverse Shear

The maximum shear force is in the y direction and has a value of 6 lbs. The maximum

transverse shear will occur in the thinner portion of the cross-section. Using the formula

bIVQ

zxy =τ , where V is the shear force, Q is the first area moment of inertia, Iz is as previously

defined, and b is the thickness of the section under examination. Q is defined as ∫ ⋅= dAyQ and

is calculated to be 0.0138 in3. The transverse shear at point A is calculated to be 114 psi, and at

point B is 15 psi.

6.2.3.3 Torsion

Based on the placement of the load, the torque applied (T) is 19.7 in lbs. A closed form

solution for the shear stress due to torsion for the cross-section that we have defined does not

exist. A good approximation is given as 21

max 23

tbT=τ , where b1 is the leg length and t is the

thickness of the cross-section. The maximum shear stress due to torsion is 3940 psi. A torsional

stress concentration will exist in the fillets of the cross-section. The stress concentrations are

63

calculated using the Trefftz criteria where 3max74.1

rt

fillet ⋅⋅= ττ . Given our thickness to radius

ratio of 1:1, the stress concentrations will have a value of 6860 psi.

6.2.3.4 Principal Stresses and Failure Criteria

The stress state for point A is

[ ]

=

114.00000932.30932.3024.8

σ ksi.

The principal stresses for this state are {σ1, σ2, σ3} = {-1.61, 0.114, 9.63} ksi. The stress state for

point B is

[ ]

−=

015.00000932.30932.3916.9

σ ksi.

The principal stresses for this state are {σ1, σ2, σ3} = {-11.29, 0.015, 1.37} ksi. The Von Mises

failure criteria, which is typical to use for ductile materials such as aluminum, is as follows,

( ) ( ) ( )[ ]213

232

2215.0 σσσσσσσ −+−+−=vm .

Calculating the Von Mises stress for point A and point B results in 10.48 ksi and 12.04 ksi. The

yield strength of 2024-T4 Aluminum is 47 ksi. This gives us an overall static margin at point A

and point B of 450% and 390% respectively. This analysis clearly shows that we have

considerable margin over the worst-case expected loading of the electronics mounting structure.

64

6.2.4 Camera Mounting System Design

A mounting fixture is provided along with the camera package. The mounting fixture

will be bolted to the foremost bulkhead of the aircraft. A small hole for the camera lens will be

cut in the fuselage cowling. More advanced vibration testing with the motor running at various

speeds and accelerometers placed at the camera mounting location will be conducted next

quarter. From the results of that testing, vibration damping, if any will be applied to the

mounting structure.

6.4 Power Consumption

To meet the requirements of the sponsor, power calculations were performed to

determine the maximum requirement of each subsystem. This allowed the team to determine the

endurance time of the airborne sensing platform and determine necessary battery to provide

power for the telemetry vision guidance and other sensors. The total power consumption was

found to be 105.5 Whrs for a little over an hour of flight time. See Appendix D.

6.5 Battery Selection

At this time the 18.5 Volt 8000 mAhr (148 Whrs) Li-Polymer battery will be designed to

power only the motor for isolation and redundancy. A separate battery was chosen based on the

power consumption of the electronics. The battery to be used at this time is a 14.8 Volt 2100

mAhr (14.6 Whrs) Li-Polymer battery. This lower voltage will also aid in voltage regulations

for the various components.

65

6.6 Vision Guidance System Design and Analysis

6.6.1 Camera Design

The team has selected a mini black-and-white camera with audio capabilities. The 14.8-

volt Li-Polymer battery supplies power for the entire camera system as shown in Figure 22. A

12-volt, positive voltage regulator and decoupling capacitor combination provides a constant

voltage to the camera and the transmitter. The regulator vendor recommends a 0.33uF capacitor

at the input and 0.1uF capacitor at the output of the regulator for the lengths of wire that this

project requires. The team may add components to this system in the future, such as switches for

system testing and component isolation. The team will test the individual components before

subsystems and the entire system. This will minimize the consequences of utilizing a faulty part.

An RCA cable transmits the NTSC video signal from the camera to the transmitter’s video input

connector. The transmitter broadcasts a 900Mhz signal to the receiver at the base station as

shown in Figure 23.

66

GNDVout

Battery

U1

23 45 67 89

1114

15 1617 1819

1312

1

10

2022242628303234363840

25

31

37

23

39

21

27

35

29

33

J1

J1 Connector

GN

D

VoutVin

M C7812

U4

Regulator

Regulator

GN

D

VoutVin

M C7805

U5

AutoPilot 50

POWERGND

Port 1 AILPort 2 ElePort 3 ThrPort 4 RudPort 5 GearPort 6 FLPPort 7 Au1Port 8 Au2Port 9 Ch9

Antenna

Receiver

Video_OutPower 12vGND

Cam era

U2

Antenna

Video_In

Power 12vGND

T x_9500

U6

Transmitter

2 RCVR POWER3 Ch1 Ailerons4 Ch2 Elev ator5 Ch3 Throttle6 Ch4 Rudder7 Ch5 Flaps8 unused

1 GNDRCVR

12 V

12 V

5 V

To Servos

To Servos

C10.1uF

C20.33uF

C3 0.33uF C4 0.1uF

14.8V

GPSAntenna

67

Figure 22: Wiring Diagram of Camera System

Figure 23: Vision Guidance System Diagram

6.6.2 RF Link Budget Analysis

In order to predict the components necessary to achieve a successful communication link

at two miles it was essential to perform a link budget analysis. This analysis uses theoretical

calculations to determine the losses associated with free space transmission, cables, and

connectors. The typical losses associated with these parameters are determined by the operating

frequency, in this case 900 MHz. The calculations use the center frequency of the 900 MHz

68

spectrum, which is assumed to be 912 MHz. Three sets of calculations were performed. Each

set had identical parameters with the exception of the output power. These calculations are only

used to get an idea of what is needed to meet the sponsor requirement of two miles. At a

minimum, the goal was to achieve link margin of 30 dB, which would account for unexpected

losses such as foliage, weather, buildings, etc. Any component that is improving over the

theoretical calculations can be expected to improve the overall link. In other words, a

component that reduces loss, increases power, or provides increased gain is expected to improve

to the link. The calculations used and the results are shown in Appendix E. These results were

used to determine the transmitters/receivers, antennas, and operating frequency.

6.6.3 Communications System Design

The implementation of each component in the communication system plays a

determining factor in the system performance. Some important parameters are connector

adapters, cable lengths, and antenna positioning. The antennas chosen for the platform require

an MMCX connector. To incorporate the antenna with the video system, an N-type female to

MMCX adapter is used. To incorporate the antenna with the integrated Maxstream radio this is

not required, as both components utilize the MMCX connector. Testing will be performed to

determine the best position of the antennas on the plane. Several options include mounting them

to the vertical stabilizer, mounting them to the side of the plane just before the tail, or mounting

the antennas to the bottom of the plane. The goal is to utilize as much of the radiation pattern as

possible, while minimizing interference from the plane and other RF sources on the platform.

The position of the antennas is the determining factor in the length of the transmission cables;

however, the routing of the cables will minimize this required length.

69

6.7 Telemetry and Stability Augmentation System Design and Analysis

6.7.1 Control

Figure 24: Control System Diagram

[logic and wiring diagrams [base station, speed controller, AP50, RC receiver, servo

connections, voltage regulators etc] NOT SURE WHAT’S GOING ON HERE!!!

70

6.8 Launch

The method for launching the platform specified by team #05008 was hand launch.

However, hand launching this platform given the size and handling characteristics could prove to

be dangerous to the operator and potentially damaging to the onboard equipment. A winch

launching system for the airborne sensing platform was investigated as an alternative. The

winch launcher provides approximately 15 minutes more endurance time over a hand launched

system. Also the winch launcher minimizes the potential for injury and equipment failure by

accelerating the platform via a small motor and cable system. See Appendix F for a picture and

link to the manufacturer web site.

7.0 FUTURE PLANS

At this time, the team has completed the major design portion of the project. The task to

be undertaken during the spring session of Senior Design II is system integration and testing. As

Senior Design II begins, the team plans to test components as they arrive from vendors and

complete the necessary machining and circuitry associated with the systems designed. Slight

design modification will occur as needed and systems integration into the airframe will then

begin according to the schedule below. Then the prototype will undergo testing in preparation

for demonstration to the Center for Imaging Science at the end of Senior Design II in May. See

Schedule below.

71

Spring Production Schedule

Task Name Start Date Finish DatePlane Construction 2/26/2005 3/16/2005Purchasing 2/26/2005 3/25/2005Class1 3/11/2005 3/11/2005Meet with team to Review Design 3/11/2005 3/11/2005Detailed CAD Plane & SubSystems 3/14/2005 3/18/2005Website Development 3/14/2005 4/29/2005Analysis & Synthesis 3/14/2005 4/15/2005Individual Tasks 3/14/2005 4/15/2005Class 2 3/18/2005 3/18/2005Test Airframe 3/21/2005 4/15/2005Meet with Sponsor 3/21/2005 3/21/2005Class 3 3/25/2005 3/25/2005Machine Telemetry Structure 3/28/2005 4/8/2005Test Electrical Components 3/28/2005 4/8/2005Class 4 4/1/2005 4/1/2005Class 5 4/8/2005 4/8/2005Test Subsystem Assemblies 4/11/2005 4/15/2005Class 6 4/15/2005 4/15/2005Test Prototype 4/18/2005 4/29/2005Update Bill of Materials 4/18/2005 4/18/2005Write CDR Techical Paper 4/19/2005 5/6/2005Class 7 4/22/2005 4/22/2005Class 8 4/29/2005 4/29/2005Demonstrate Prototype 5/2/2005 5/6/2005Class 9 5/6/2005 5/6/2005Sanity Check 5/9/2005 5/9/2005Practice CDR Presentation 5/11/2005 5/11/2005Class 10 CDR 5/13/2005 5/13/2005

Week 9 Week 10Week 5 Week 6 Week 7 Week 8Week 1 Week 2 Week 3 Week 4

Figure 25: Projected Schedule

8.0 BUDGET

The combined budget for this project and the project being completed by team #05008

totals $10,000. Approximately 10% of the overall budget has been allotted to team #05008;

therefore, the goal is to complete our portion of the project with a budget of $9,000. Based on

the current Bill of Materials we are target to complete the project under budget. See Appendix G.

We expect some additional purchases to arise during Senior Design II as we continue with

assembly and test of the subsystems and airframe; however, we do not expect these additional

costs to exceed the given budget for the project.

9.0 CONCLUSION

The team has completed the first portion of Senior Design and created a preliminary

design for the Airborne Sensing Platform test bed. Although this was extremely challenging, the

true difficulty will arise when integration and testing begins next quarter. The team has

attempted to anticipate trouble areas and allow the schedule to accommodate such pitfalls. The

72

team will rely on individual team member skills, departmental, and sponsor assistance to

successfully complete a working prototype for the Center of Imaging Science at the end of

Senior Design II in May of 2005. The team has created a strong set of documentation throughout

the project, both in the PDR and the technical data package binder. This will assist the team in

completing the project on time, under budget, and to the specifications of the Center for Imaging

Science.

73

APPENDIX A – AIRFRAME STABILITY CALCULATIONS

Takeoff Performance Equations Used

2LDpD KCCC +=

eARK

πφ=

eARa

aa

π0

0

3.571+

=

( )0αα −= aCL

payloademptygross WWW +=

bcS =

LSCVL 2

21 ρ=

DSCVD 2

21 ρ=

cbAR =

74

Symbols:

α = AoA = angle of attack

0α zero-lift angle of attack

AR wing aspect ratio

0a 2-D lift coefficient slope

a 3-D lift coefficient slope

b wing span

c wing chord

LC lift coefficient

DC drag coefficient

PDC parasite drag coefficient

75

Stability & Control Equations Used

α

α

L

M

CC

inMStatic−

=arg_

cSlSV TT

H ⋅⋅=

4/cxac =

ee

tLHMcg

CVC δ

δ∂∂

−=∆ ,

76

( )( ) ( )( ) ( )( ) ( )( )

( )( ) ( )( ) ( )( ) ( )( )

)(

cossinsincos

cossinsincos

,0

21

2

21

2

21

2

21

2

222

1

11

1

11

1

11

1

111

ee LMWLM

TrimLMLMe

McgtailMcgwMcgwMcg

tailHTTMcgtail

w

cqwDw

w

cqwLw

w

acwcqDw

w

acwcqLwMacwMcgw

w

cqwDw

w

cqwLw

w

acwcqDw

w

acwcqLwMacwMcgw

CCCCCCCC

CCCC

VaC

cz

Cc

zC

cxx

Cc

xxCCC

cz

Cc

zC

cxx

Cc

xxCCC

δααδ

ααδ

αη

αααα

αααα

⋅−⋅⋅+⋅

−=

++=

⋅⋅⋅−=

−

+

−+

−+=

−

+

−+

−+=

Symbols:

HV horizontal tail volume

TS horizontal tail area

acx horizontal distance from reference plane to

aerodynamic center of subscripted component

cgx horizontal distance from reference plane to CG

cgz vertical distance to CG of subscripted

component

APPENDIX B – CG CALCULATIONS

Cg Calculation

W total = 11.352 lbs. L total = 48.5 in h empennage = 10 inW empennage = 0.600 lbs. L fuselage = 33.5 in h telemetry = 18 inW telemetry = 1.000 lbs. L empennage= 12 in h battery = 39.5 inW battery = 1.713 lbs. L cowling = 3 in h fuselage = 28.75 inW fuselage = 2.000 lbs. h cowling = 47 inW cowling = 0.400 lbs. h motor = 47 inW motor = 0.851 lbs. h payload = 39.5 inW payload = 3.000 lbs. h camera = 47 inW camera = 0.094 lbs. h tail = 4 inW total05009 = 1.094 lbs.W tail = 0.600 lbs.

#05009 Components

Cg*Wtotal05009=Wtelemetry*htelemetry+Wcamera*hcamera

Cg 5009 = 20.485714 in

Cg total = 29.3575 in

Assumptions: 1/4 Chord of Wing is Placed at CgWhen actual measurements were not available, PDR data was usedCg total does not include tailh distance referenced from empennage

ComponentsIndividuali

hWWCn

iiitotalg

≡

=∗ ∑=1

*

77

78

APPENDIX C – DETAILED STRUCTURAL DRAWINGS

79

80

81

82

83

APPENDIX D – PATH LOSS CALCULATIONS

( )

)()()(Margin

)()()(

)()()/(

)(20)(2056.35

1.0)(

)()(/

1010

LosSpaceFreeBudgetPowerRxBudgetPowerTx

LossConnectorLossCableGainAntennaySensitivitBudgetPowerRx

LossConnectorLossCablePowerAntennaTxBudgetPowerTx

MilesinLengthLinkLogMHzinFrequencyLogLossSpaceFree

GHzinFrequencyConnectorsOfNumberLossConnector

Lengthft

LossLossCable

GainAntennaTxPCowerTxPowerAntennaTx

−+=

−−+=

−−=

++=

×=

×=

+=

84

85

86

APPENDIX E – POWER BUDGET ANALYSIS

87

Component mA V mW (max) Runtime (min) Total Energy Used Used (Whr)Motor Climb 4870.00 18.50 90095.00 13.50 2.03E+01Motor Cruise/Loiter 4060.00 18.50 75110.00 60.00 7.51E+01Auto Pilot 50 150.00 8.00 1200.00 80.00 1.60E+00Camera (VC-210B-Audio) 90.00 12.00 1080.00 80.00 1.44E+00Servos 500.00 5.00 2500.00 73.50 3.06E+00Pitot Tube 80.00 0.00E+00Pressure Transducer 80.00 0.00E+00Temp Sensor (SMT 160-30) 0.20 5.00 1.00 80.00 1.33E-03900 MHz Transmitter (TX-9500) 250.00 12.00 3000.00 80.00 4.00E+00

148.00 Energy Available (Whr)105.49 Energy Consumed (Whr)42.51 Energy Remaining (Whr)

negligiblenegligible

Assume 2.5 ft/sec climb to 1000 feet

APPENDIX F – WINCH LAUNCH

88

www.superskeg.com

Winch Kit

89

APPENDIX G – BILL OF MATERIALS

2/18/2005

Product NumberTeam

ChargedDescription Status Quantity

Retail Price Per Unit

Total Price

LXPT40 #05008 Tower Hobbies Build-It CA- Thick Glue 2 oz. Arrived 1 $5.99 $5.99#05008 Derek Aero-Team Tail Build Complete 1 N/A $200.00

LXPT38 #05008 Tower Hobbies Build-It CA Thin Glue 2 oz. Arrived 1 $5.99 $5.99LXK110 #05008 Great Planes CA Hinges 3/4"x1" (24) Arrived 1 $2.99 $2.99LXL431 #05008 Hobbico Latex Foam Rubber 1/2" Arrived 3 $4.49 $13.47LXK108 #05008 Great Planes Nylon Control Horns Large (2) Arrived 3 $0.95 $2.85LX3609 #05008 Astro Flight Power Supply 13.5V Arrived 1 $74.95 $74.95

LXFWW2 #05008 Astro Flight 109 Lithium Charger 1-9 Cell 7.5 Amps BackOrder 1 $114.99 $114.99LXHRC2 #05008 APC 13x10 Folding Prop Arrived 2 $7.19 $14.38LXZL06 #05008 APC folding Propeller hub 45mm Arrived 2 $4.79 $9.58LXJD33 #05008 Tower Hobbies Plywood 1/8x6x12" Arrived 2 $1.79 $3.58LXJD32 #05008 Tower Hobbies Plywood 1/16x6x12" Arrived 2 $1.49 $2.98LXD867 #05008 Dubro Threaded Rod 2-56 12" (6) Arrived 1 $2.89 $2.89LXN666 #05008 Hitec HS-225MG Mighty Mini BB MG Servo J Arrived 4 $27.99 $111.96LXHV43 #05008 Top Flite Monokote Blue 6' Arrived 1 $10.99 $10.99

PM412018 #05008 AXI4120-18 Model Motors - DC Motor Arrived 1 $139.00 $139.00JESAP70P #05008 Jeti 70A Speed Controller Arrived 1 $147.20 $147.20

#05008 18.2v Lithium Battery Arrived 1 $399.00 $399.00PM41002 #05008 AXI4120 Model Motors - Motor Mount Arrived 1 $18.50 $18.50LXK196 #05008 Great Planes Nylon Wing Bolt ¼-20x2 (4) Arrived 3 $1.25 $3.75

#05009 9 Channel Futaba Radio Controller Pending 1 $799.99 $799.99#05009 AP50 AutoPilot Autonomous Flight Hardware: GPS, Inertial, Rx/Tx Pending 1 $5,000.00 $5,000.00

VC-210B-AUDIO #05009SONY CCD Camera w/Audio CH- Circuit Specialists Inc (yahoo store) http://shop.store.yahoo.com/webtronics/mibwcav.html4 Pending 1 $34.50 $34.50

#05009 Aluminum stock McMaster Pending 1 $22.48 $22.48399-2054-ND #05009 Digikey.com - Capacitor, ceramic, 0.1uF,50V Pending 5 $0.21 $1.05399-2099-ND #05009 Digikey.com - Capacitor, ceramic, 0.33uF,50V Pending 5 $0.83 $4.15

MC7812CTOS-ND #05009 Digikey.com - Regulator, pos, 1A, 12V Pending 2 $0.58 $1.16MC7805CTOS-ND #05009 Regulator, pos, 1A, 5V Pending 2 $0.58 $1.16

LXHUP0 #05009 Futaba R319DPS 9-Channel PCM Receiver Synthesized Pending 1 $179.99 $179.99LXH258 #05009 Futaba TK50 & 72 FM/PCM Transmitter Module Pending 1 $54.99 $54.99

#05009 TX-9500 A/V Mini-Transmitter Pending 1 $129.99 $129.99#05009 RX-900 A/V Receiver www.eyespyvideo.com Pending 1 $109.99 $109.99#05009 Winch System - Tom McCann Pending 1 $600.00 $600.00#05009 Telemaster Building Materials Pending 1 $200.00 $200.00

A09-HBMM-P5I #05009 Omni Directional Airborne Antenna - MaxStream Pending 2 $25.00 $50.00OD9-6 #05009 Omni Dir. Basestation Antenna - Streak Wave (Order Online) Pending 2 $68.95 $137.90

TP2100-4S #05009 14.8 V 2100 mAh 4 Cell Li Polymer Battery Pending 1 $99.95 $99.95

Total Budget: $10,000 Subtotal: $8,291.11

Percent Spent: 82.91%

Rochester Institute of Technology, www.designserver.rit.edu

Bill of Materials*Covers Costs incured by team #

05008 & #05009

90