G_ST_TSH_017B - GAPS

TECHNICAL DESCRIPTION

GAPS technical description

www.ixblue.com G/ST/TSH/017B Page 2 of 29

Table of content

1. GAPS concept ........................................................................................................................................................... 3

1.1. Introduction ................................................................................................................................................... 3

1.2. Concept .......................................................................................................................................................... 3

2. GAPS technical description ..................................................................................................................................... 5

2.1. Inertial Navigation System (INS) .................................................................................................................... 5

2.2. GAPS USBL acoustic array .............................................................................................................................. 6

2.3. Positioning method & signal processing ....................................................................................................... 7

2.4. Software ......................................................................................................................................................... 8

3. Operating GAPS ..................................................................................................................................................... 12

3.1. Typical system configuration ....................................................................................................................... 12

3.2. System deployment ..................................................................................................................................... 13

3.3. Mechanical installation ................................................................................................................................ 13

4. GAPS transponder/Responders ............................................................................................................................ 14

4.1. MT9xx series Transponder/Responder ....................................................................................................... 16

4.2. MT8xx series Transponder/Responder ....................................................................................................... 17

4.3. Long battery life ET8x2 transponders series ............................................................................................... 18

5. GAPS key benefits.................................................................................................................................................. 19

6. GAPS system performances and specifications .................................................................................................... 20

6.1. Subsea positioning performance ................................................................................................................. 20

6.2. Operating / environment / Mechanical ...................................................................................................... 21

7. Packing list, ordering references ........................................................................................................................... 22

7.1. Standard package ......................................................................................................................................... 22

7.2. Optional accessories and services ............................................................................................................... 22

8. Appendix ................................................................................................................................................................ 24

8.1. GAPS head connector wiring ....................................................................................................................... 24

8.2. GAPS main cable (50m long) ........................................................................................................................ 24

8.3. GAPS ECB (Easy Connect Box) ...................................................................................................................... 25

8.4. GAPS Mechanical interface .......................................................................................................................... 27

8.5. GAPS transponders / Responders ............................................................................................................... 29



1. GAPS concept

1.1. Introduction

GAPS is an integrated underwater positioning solution which makes USBL (Ultra Short Base Line) underwater positioning extremely simple to operate from any vessel, using a portable and truly pre-calibrated USBL head coupled with internal INS (Inertial Navigation System) and GPS, with no compromise on performances. GAPS is used to measure the absolute position of one or more subsea objects or vehicles which can manoeuvre at depths up to 4,000 meters, with 200deg hemispherical coverage below the antenna, and typically 0.2% accuracy of the range depending on environmental and operational conditions. These objects or vehicles are located using acoustic transponders or beacons and a subsurface acoustic array (GAPS head) typically deployed under water below the ship hull, on a side pole or a buoy. GAPS typical deployments:

Hull mount Pole mount Buoy mount

1.2. Concept Positioning on the surface at sea has found its reference technology in GPS, a system that offers a straightforward and inexpensive solution which has readily found a place in the daily routines of hydrographers, marine surveyors and in maritime work in general. Unfortunately, solutions to the problem of subsea positioning are complicated by the fact that GPS radio signals do not penetrate water. Underwater acoustic solutions or Inertial Navigation solutions have to be considered to overcome this situation.

1.2.1. Conventional Acoustic Positioning Solutions

In the subsea environment, the solution is to use a positioning system based on the triangulation of ranges to the object to track, using acoustic signals time of travel. For example, the LBL system requires the deployment of a set of beacons on the sea bed before operations can begin. LBL also requires a long (and costly) calibration phase in order to obtain measurements that are accurate, but with a time lag and limited to the area in which the beacons have been deployed.



A conventional USBL system is mounted on the ship, which makes mobile coverage possible. However, the installation of this type of system on board is neither quick nor easy because USBL system requires the availability of external data such as ship’s heading, roll, pitch and position. The integration of this data deriving from GPS, gyrocompasses and attitude sensors supplied by different manufacturers using their own formats and protocols and supported by different software, can be a long process. In addition, this information must of course be available to the highest possible accuracy for optimal performances. This imposes the need for very precise measurement of the position offsets and misalignments of the various sensors. This installation phase must then be supplemented by a statistical calibration process conducted at sea in order to optimize overall system performance.

In practice, integration and calibration can take up to several days and the calibration must be repeated every time the system is installed. So in practical terms:

(i) Conventional USBL is a dedicated system that may be installed once on a ship and left on board for its entire useful life or recalibrated after every new installation)

(ii) The cost of a complete system (USBL, GPS, gyrocompass, attitude sensor, and computer) is prohibitively expensive for use on small vessels.

1.2.2. The innovative GAPS solution

Taking advantage of its unique expertise in acoustic positioning and inertial sensors, ixblue introduces GAPS, the only acoustic + inertial integrated positioning system for marine and subsea applications. It is an all-in-one system which can provide at the same time the position of a surface vessel and of several subsea vehicles or divers. It also provides a very accurate heading and attitude for the surface vessel with the highest accuracy (comparable to existing systems on the market) and unrivalled performances in shallow or extreme shallow water depth thanks to unique receiving antenna design and enhanced digital signal processing techniques. GAPS is a portable system (light weight and reduced size), does not require any complicated installation (all-in-one pre-calibrated system), features very high performance thanks to data fusion of Acoustic, inertial and GPS technologies and finally has no limit in terms of operation area (shallow and deep water, horizontal and vertical channel, short or long range).



2. GAPS technical description GAPS comprises in a single lightweight housing (carbon fiber made) all required components to achieve USBL positioning with no need of additional external sensor. The system is plug and play, deployable in an instant, and can be operated immediately thanks to its pre-calibrated concept. (Internal high grade motion and heading sensors)

Internal INS Electronic package 3-D acoustic array GAPS pre-

assembled External pressure

housing

2.1. Inertial Navigation System (INS) The core of GAPS INS is the inertial measurement unit (IMU) composed of three Fiber Optic Gyroscopes (FOG) and three accelerometers mounted on orthogonal axis. The FOGs provide the instantaneous rotation of the system and the accelerometers provide the instantaneous acceleration of the system (taking into account the gravity forces which are indistinguishable from accelerations). The benefits of the INS (Inertial Navigation System) in GAPS are multiple and complementary:

2.1.1. Electronically stabilized receiving antenna

Underwater objects or specific points are localized using transponders and an acoustic array or antenna (USBL base) on surface. The positioning is based on the two-way acoustic communication between the surface acoustic array and the transponders, with an optional downward electrical data link capability through cables connecting a specific transponder and the ship. To localize the target, the system interrogates the transponder installed on it then receives its reply and measures the slant distance (with sound velocity profile corrections), and two bearing angles, derived from the two orthogonal baselines in the surface acoustic array. Since the acoustic array is installed on a moving platform (surface ship) its absolute position must be known with sufficient accuracy and its motion carefully monitored and compensated in order to get the best performances. The INS provides Heading, Pitch and Roll angles to the system with the highest accuracy (0.01deg typ.) so that the exact attitude of the antenna is known at time of transponder reply. The INS is



carefully assembled and mechanically aligned with the acoustic USBL base during the manufacturing of the GAPS so that no further calibration is required. The system so formed is accurate, and pre-calibrated. Note: Motion compensation (Heading, Pitch, Roll) is the most important source of error in the total budget error for USBL. For instance 0.1deg misalignment generates 8m error circle at full range (4,000m) The best accuracy here is critical to the global performance

2.1.2. Geo-referenced, GPS robust, absolute positioning An Inertial Navigation System coupled with a GPS (as it is configured in GAPS) is able to calculate and maintain its position with … - a better accuracy than GPS alone (tight coupling reduces noise, improves accuracy), - at a high data rate (typically 100Hz) - position remains valid with no GPS available for minutes. (robust to GPS outages when system

is operated in harsh environment for GPS like harbours, structures, etc) That position is then available within the GAPS system which will immediately calculate the absolute coordinates of the objects being tracked with no need of any further processing.

2.1.3. Two instruments available in one

The internal INS is used within GAPS for antenna stabilisation and absolute positioning as well as fully available for typical INS operations: - Provides absolute and GPS robust positioning of the support vessel - Provides Heading, Pitch, Roll, Heave information for third party and simultaneous use such as

multibeam attitude monitoring All standard communication protocols and features available with IXBLUE INS are then fully available for use while underwater positioning operations are in progress

2.2. GAPS USBL acoustic array

The GAPS Acoustic Array is composed of one (1) transmission transducer, four (4) reception hydrophones. It ensures the sending of the acoustic (or electrical) triggering signal to the Transponders and the receiving of their replies. The acoustic array of the GAPS is 3D: it has four receiving hydrophone on the vertices of a tetrahedron (four is the minimum number of hydrophone for unambiguous positioning in 3-D space). This design implies very good angular coverage (>200 degrees aperture below the acoustic antenna).



2.3. Positioning method & signal processing The acoustic performance of GAPS USBL positioning system is a delicate compromise between several parameters and environmental conditions.

- Operating frequency and signal modulation - Automatic Gain Control mechanism - Sophisticated digital signal processing techniques. - Geometry of the receiving array

As a result of it and together with the internal INS + 3D acoustic array antenna GAPS is featuring unique performances in commonly difficult conditions such as shallow or extreme shallow water (down to a few meters) as well as extremely noisy environment often met in marine construction activity.

2.3.1. Wideband modulation

Conventional system use Single Pulse / Single Frequency modulation techniques for historical reasons and simple hardware / software requirements. However the performances are poor in terms of immunity to noise and multipath effect which are commonly met conditions in shallow or extreme shallow water. GAPS and transponders implement a wideband coding technique based on multi frequency modulated pulse and coherent signal processing to detect transponders / pingers replies with excellent SNR (additional processing gain) and robust to noise, Doppler and multipath effects. Additionally the selected wideband modulation offers a good code inter-correlation characteristic which allows simultaneous multiple targets tracking capability.

Pulse length : 10ms Frequency band : 9kHz Central frequency : 26kHz Antenna size : 25cm (distance between opposite hydrophone in the horizontal plan)

2.3.2. AGC – Automatic Gain Control

In order to further improve its performance GAPS features an automatic Gain Control mechanism which reacts and adapts the receiving circuits to a number of parameters. The following operations are carried out in real time by the internal electronics / firmware - Estimate the noise level in the acoustic channel and adapts the receiving threshold - Adapt the gain to the signal amplitude vs. distance to target - High noise level or pulse noise management - Multiple replies management (tracking multiple targets) The graphs below illustrate the receiving threshold change with some typical (real life) data examples: Multipath scenario



Received signal + echoes vs. time

Processed signal and detection threshold (red)

High noise / pulse noise scenario

Received signal + pulse noise

Processed signal and detection threshold (red)

2.3.3. Position calculation

Once the signal is extracted from its noise and validated by the digital signal processing section TOT (Time of Travel to target) is measured and angles respective to electronically stabilised receiving Antenna (INS motion compensation) are taken. This raw data must be processed accordingly in order to obtain a valid position. Several operations are carried out: - Correct ToT with the compensated Sound Profile that has been initialised into GAPS memory

prior to tracking operation starts - Detect and correct if possible wrong answers:

o Coherence of the measurement within the four hydrophones o Detect sector jumps o Compare position with predicted position (taking into account past results) o etc

Thanks to the internal INS a final and directly usable geo-referenced position is produced by the system and sent to navigation application software for display, together with a comprehensive quality factor reporting all its main characteristics and significant facts.

2.4. Software

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2.4.1. Man Machine Interface (MMI) software for control and display

The Control System is any PC on which the MMI software provided with GAPS is installed. It can be connected to GAPS directly through the MMI DIALOG (DB9) serial link available on the Easy Connect Box (ECB) supplied with the system. The MMI GAPS software is used to:

(i) Configure GAPS (input/output configuration, sound velocity profile, etc). (ii) Visualize the position(s) of the transponder(s) – however, this is not a true

positioning/navigation package.

User-friendly menu screens allow the operator to define GAPS setting before deployment in an instant THE USE OF THE CONTROL SYSTEM IN NOT MANDATORY ONCE GAPS IS CONFIGURED: GAPS keeps all its settings when powered off and resume its last behaviour when started up. Example; (extract from GAPS Quick Start Guide)

2.4.2. GECDIS position display and navigation package GECDIS is a powerful navigational tool with a geographic information system, ECDIS certified, working on standard computers fitted with Windows® NT, Windows® 2000 or Windows® XP. SODENA, a sister company of ixblue group, developed this software dedicated to Cartography and Navigation applications. A recent project awarded by the French Navy concerns the installation of this software on the whole navy fleet (120 vessels) to display geo-referenced aerial, surface and subsea information collected over a user-defined area (Integrated bridge information package).



GECDIS contributes to safe navigation and allows to carry out route planning and

route monitoring in a simple and reliable way. Navigational aid is given by displaying electronic charts, on which information from

the ship equipment and sensors connected to GECDIS are displayed, such as: GPS, Radar (overlaid or/and ARPA tracks), gyrocompass, log, depth-sounder or any navigation device. Other information can also be displayed onto specific layers, such as weather files.

GECDIS fits IMO and IEC regulations for cartographical data storage (SP57) and their displaying (SP52). GECDIS can also read C-Map vector and raster charts (British Admiralty, etc.).

GECDIS is fitted with in-line and independent tools, allowing system customization according to three levels: ship's equipment, the user and his practices, hierarchy and access rights.

Furthermore, GECDIS provides independent back-up arrangements to ensure safe navigation in case of a failure. So if your machine suddenly malfunctions, the software parameters do not need to be reinitialized manually and operator settings do not change.



2.4.3. Communication protocol and software library All communication to and from GAPS are achieved using industry standard NMEA0183 data telegram through the serial input/output ports, messages content is fully described in the user manual provided with the equipment. In addition to its standard proprietary communication protocol (“GAPS standard”) GAPS is featuring native compatibility with other ixblue sensors and subsystems (PHINS, RAMSES, etc..) and can emulate other industry standard protocols. This allows GAPS to smoothly interface to ixblue or already existing third party hardware / software, or easily interface to peripherals or main system such as DP engines. Among them ...

DP SIMRAD HiPap

NAUTRONIX APS

ixblue USBL INS1

POSIDONIA 6000

PHINS standard message

HEHDT

HALLIBURTON

NAVIGATION



3. Operating GAPS GAPS is a fully integrated system which does not require any further third party equipment to be operated. A comprehensive but reduced list of equipment is provided with the system. Its compact size, light weight, operating versatility and pre-calibrated characteristics make it usable in almost any kind of tracking operation with very quick and easy deployment.

3.1. Typical system configuration

A standard GAPS system requires the following components for a ready to use configuration The whole system is packed in two reusable transit cases and a plywood transit case for the transponder only

GAPS head

This is the main part of the system, which comprises of the acoustic array to communicate with the transponder(s) installed on the target(s), the INS for motion compensation, and all electronics and signal processing.

‘Y’ junction cable

Connects to the GAPS unit system, GPS active antenna, and the main junction cable to surface application (not required in case GPS data is fed through main junction cable).

Main cable

50m long cable used to communicate with GAPS subsurface unit (data output, programming, synchronization, power supply).

GPS receiver and cable

A complete turnkey solution is provided, including GPS receiver and 10m long cable.

(GPS, DGPS WAAS/EGNOS compatible)

Easy Connect Box

Designed to interface between the GAPS and external peripherals. It includes power supply from mains & 28Vdc, and RS422 / RS232 converters and input/output synchro on BNC.



3.2. System deployment Components of the system simply connect together as shown below (extract of GAPS Quick Start Guide)

The GAPS system is calibrated once for all in factory and does not require further calibration procedure after installation or reinstallation. The system is fully portable and can be deployed in less than one hour depending on the mode of operation (hull mount pole mount, cable hanged, buoy, etc).

3.3. Mechanical installation

open boxes

+10 min

+25 min

+40 min



Examples below demonstrate the extreme ease of operation of the system which does not require sophisticated mechanical pole or deployment machine to operate it. Thanks to its internal sensors and PRE-CALIBRATED configuration GAPS is fully PORTABLE and PLUG & PLAY. Although no installation system is supplied with GAPS, ixblue will be please to study with or for its customers any mode of deployment depending on the ship, buoy, or expected mode of operation.

3.3.1. Pole mounted example

3.3.2. Under hull installation example

3.3.3. Cable deployment, buoy or catamaran installation examples

4. GAPS Transponder/Responders



Transponders/Responders are the remote part of the GAPS positioning solution. They are installed on the subsea vehicle or target to position. They communicate with the acoustic array of the GAPS using acoustic pulses through the water column. Three main categories with several models are available depending on the mode of operation, power supply, water depth and weight considerations.



4.1. MT9x2 series Transponder/Responder

The MT9xx range has been developed after a few years field accumulated experience and valuable return from our customers. These new transponders offer the same acoustic characteristics already featured by previous versions with new attractive characteristics such as internal rechargeable batteries, fully programmable without opening of the pressure housing, and more reply codes for tracking of multiple vehicles in the same area. The MT912S version is a shallow water model (1,000m) which is free to export. (No licence required)

4.1.1. MT9x2 series common characteristics

Modes of operation Transponder mode / Responder mode External ON/OFF plug Fully programmable through RS232 / USB without opening of the pressure

housing Power supply

Internal Ni-MH rechargeable batteries & battery charger (4 months listening, up to 100,000 replies @ 188dB transmit level)

External power supply (15-30Vdc, 15W peak) Acoustic

4 x individual interrogation frequencies (tonal, user programmable) 12 x M-FSK reply codes: (user programmable)

Stainless steel housing and polyurethane coating

4.1.2. MT9x2 product range

Version MT912S-R MT912S-R/HD MT932S-R MT932S-R/HD Depth rating 1,000m 1,000m 3,000m 3,000m

Transducer head Integral Remote (3m long cable)

integral Remote (3m long cable)

Size (electronics) 340mm w/o connector, 91mm OD

290mm w/o connector, 91mm OD

Size (transducer) 91mm OD 80mm long w/o

connector

Weight 3.9kg (Air) 2.0kg (Water)

4.8kg (Air) 2.5kg (Water)



4.2. MT8x2 series Transponder/Responder

A range of reduced size & universal transponder / responder designed for easy installation on most vehicles / targets. They can be manufactured of hard anodizing aluminium or stainless steel, with integral or remote transducer head.

4.2.1. MT8x2 series common characteristics

Modes of operation Transponder mode, Responder mode ON/OFF switch on lower end plate programmable through internal switches 4 x individual interrogation frequencies (tonal, user programmable) 2 x M-FSK reply codes: (user programmable)

Power supply Internal lithium DL-123 cells

(4 months listening, up to 45,000 replies @ 188dB transmit level) External power supply (15-40Vdc, 20W peak)

Light aluminium alloy & hard anodising or super duplex stainless steel

4.2.2. MT8x2 product range

Version MT832E-R MT832E-R/HD MT862S-R MT862S-R/HD

Depth rating 3,000m 3,000m 6,000m 6,000m

Housing 6061T6 aluminium 6061T6 aluminium Super Duplex SS Super Duplex SS


integral Remote (3m long cable)

Size (electronics) 500mm with connector, 70 mm OD

370mm (w/o bulkheads), 70mm OD

500mm with connector, 70 mm OD


Size (transducer) N/A 100mm Height (w/o plug), 65mm OD

N/A 100mm Height (w/o plug), 65mm OD

Weight 2.7kg (Air) 1.1kg (Water)






4.3. Long battery life ET862 Transponders/Responders series

The “FAT” housing ET862S GAPS transponder’s electronics is featuring the same acoustic / electric performances and functions than the miniature MT8x2 series. Installed in a larger pressure housing it can accommodate a larger set of batteries for extended deployment life. The ET862S has been designed for long deployment life with no external power supply available.

4.3.1. ET8x2 series common characteristics

Modes of operation Transponder mode, Responder mode ON/OFF switch on lower end plate programmable through internal switches 4 x individual interrogation frequencies (tonal, user programmable) 2 x M-FSK reply codes: (user programmable)

Power supply Internal alkaline or lithium ‘D’ size cells

(48 months listening, up to 500,000 replies @ 188dB transmit level) External power supply (15-40Vdc, 20W peak)

super duplex stainless steel

Version ET862S-R ET862S-R/HD

Depth rating 6,000m 6,000m


Size (electronics) 712mm with connector,

130 mm OD


Size (transducer) N/A 100mm Height (w/o plug), 65mm OD

Weight 25.5kg (Air) 16kg (Water)

27kg (Air) 17kg (Water)



5. GAPS key benefits The innovative and unique principle of GAPS merging INS and USBL techniques in a compact, plug & play, calibration free system offers many advantages compared to existing conventional USBL:

Universal / generic underwater positioning system

The capacity of GAPS to track vehicles / subsea targets in deep water or shallow water (high elevation target) in all kinds of environment (noise) allows its use in a wide variety of applications. In particular GAPS demonstrated its unique performances and capacity to track vehicles in extreme shallow water (few meters)

Ready to use GAPS is including all components required for a USBL system to operate. There is no need of external sensors (gyro, motion sensor, GPS...) and interfacing to them, and no need to spend time calibrating the system after installation. Setting to work with full performances is achieved in less than one hour.

Flexible installation GAPS can be deployed virtually in any way, including simple side pole, moon pool, hanging on cable or floating remote platform. Moving GAPS from one vessel to the other is fast and efficient and sharing the equipment within several vessels is extremely simple.

Easy to use equipment The software which comes with the system allows easy programming of the deployment configuration (GPS and GAPS offsets, transponders, etc). GECDIS optional navigation package is an easy and professional solution for tracking display. Compatibility with third party display package allows instant replacement of existing USBL.

Available internal INS The internal INS is available for additional application. It provides ultimate performances for heading, pitch, roll that can be used for motion compensation of surface vessel (GAPS on deployment machine or stable pole required in that case). GAPS calculates its own position with GPS noise free and robust performance thanks to INS algorithm.

Multiple transponders tracking GAPS can track up to 8 beacons in the field. Compatibility with other manufacturers’ beacons is available (1st quarter 2008) provided interrogation and replies are using tone modulation. (Performances likely to be lower with third party equipment however)

Compact, lightweight, corrosion free GAPS housing is made of carbon fiber providing lightweight (16kg in air, -7kg in water), corrosion resistance, and is easy to handle. The complete USBL fits in less than 300mm diameter x 650mm overall length, with no required surface electronic package and additional sensors.

Upgradable The system is assembled from standard components and subassemblies do all belong to ixblue’s core business. Modern technology and powerful electronics mostly owned by ixblue (patents on INS, GAPS) is used for various applications and different markets and is a warranty of robustness, upgradeability and possibility to easily extend the system in performances or coverage.

Low maintenance GAPS integrates in a corrosion free and compact housing all required components (fully static) for the system to work. There is no need of calibration or regular inspection. Exposed parts (hydrophones) are now available for easy replacement in the field should it be required with no mandatory recalibration of the system versus a slight degradation of performance at long ranges.

A solution capable to evolve, for future applications State-of-the-art positioning systems are based on acoustic positioning, inertial systems, imagery processing, data fusion. For each of those technologies, ixblue belongs to the rare companies which are really highly qualified. But more importantly, ixblue is the only company whose expertise embraces this whole spectrum. GAPS smoothly interfaces with other company’s products.

Worldwide 24/7 support ixblue commercial organisation includes an ever-expanding worldwide network of subsidiaries and partners to provide 24/7 technical assistance to customers. Our ISO 9001-2000 certification is a warranty of quality of the equipment and services as well as traceability for long term support of the solution.



6. GAPS system performances and specifications

Nominal absolute coordinates tracking performance of GAPS is 4,000m slant range with typical accuracy of 0.2% x range. This is a global error budget including the contribution of all internal sensors (pitch, roll, heading, GPS grade). However all underwater acoustics systems are subject to environmental data such as ambient noise and propagation conditions. Accuracy and range are nominal in vertical mode of operation and deep water (target below the acoustic array), and decreases in horizontal mode of operation due to multipath effect, poorer sound velocity profile estimate and compensation.

6.1. Subsea positioning performance

Positioning accuracy (1)(2)

0.2% x slant range

Operating range (1)(2)

4,000m

Coverage 200 deg below acoustic array

Operating frequency 22 to 30 kHz MFSK (chirp)

Position refresh rate 1 second min (acoustic, depends on range)

10 Hz with predictive filter

Communication protocol

Serial communication link NMEA proprietary GAPS protocol

Multiple other NMEA or binary data telegrams Native compatibility with ixblue products

(1) GAPS is a Global positioning system which provides absolute geo-referenced positioning of the tracked vehicles/object.. Unlike other conventional USBL system the performance (0.2% x range) is inclusive of all sources of error such as GPS (DGPS mode), motion and heading internal sensors

(2) Range and accuracy of the system depend on ambient acoustic propagation conditions, water depth and signal to noise ratio (SNR) and GPS grade. The accuracy and range are nominal in vertical mode of operation and deep water (target below the acoustic array), and decrease in horizontal mode of operation due to multipath effect, Sound Velocity profile. Nominal 0.2% accuracy is specified for a NIS=70dB (SNR=34dB), 1000m water depth, target below the acoustic array +/-30deg, sea state 6, Sound Velocity ideally compensated:

GAPS maximum range prediction vs. noise level (transponder signal level 188dB ref 1µPa @1m)

GAPS Accuracy versus SNR



Slant Distance ≥ 1,000 m

Vertical Angle < 30 deg

GPS error ≤ 1.5 m

6.2. Operating / environment / Mechanical

Power Supply range 100 to 240 VAC / 50~60Hz ECB Power supply

28 /36VDC on external power supply

Operating temperature -5 / +35 deg. Celsius

Storage temperature -20 / +70 deg. Celsius

Housing Carbon fibre housing + epoxy paint

Weight in air / water 16kg - _7kg (positive buoyant)

Overall dimension 638mm x 296mm OD

Depth rate 25m standard

Main GAPS cable diameter 15 mm

Length 50 m standard

(100m optional with separate power supply (p/n OIGAPS-ALIMECB)

Dynamic bend radius 150 mm

Static bend radius 75 mm

Breaking strength 150 DaN



7. Packing list, ordering references

7.1. Standard package

7.1.1. GAPS SYSTEM

Qty. Designation Ordering code

1 GAPS main system Box #1, including - GAPS acoustic array and INS - CD box (software package, quick start guide, user

manual electronic copy)

OIGAPS-CARBONE

1 GAPS accessories Box #2, including - GPS active antenna - Easy connect box - Main cable (50m long) - GPS extension cable (15m long) - ‘Y’ junction cable

7.1.2. GAPS accessories included in standard package:

Qty. Designation Ordering code

1 GPS active antenna OIGPS-GAPS

1 GPS extension cable (15m long) OIGAPS-JC-GPS

1 ‘Y’ junction cable OIGAPS-JC-Y

1 GAPS interface / power supply box (ECB) OIGAPS-ECB

1 GAPS ECB to computer serial cable (RS232) --CASUBDB9

1 Mains power supply cable (EEC standard) FOCORSECCEE-2.5

1 GAPS main junction cable (50m) OIGAPS-JC-MAIN

1 GAPS head N/A

1 GAPS head dummy plug + locking sleeve P_DLSA-F / P_MCD_16F

1 GPS head dummy plug + locking sleeve P_MCDC6-F / P_MCDL-F

7.2. Optional accessories and services

7.2.1. Accessories

Designation Ordering code

GAPS extended length main junction cable (100m) (4)

9300195-100A

GAPS 48VDC external power supply block OIGAPS-ALIMECB

GAPS decoupling washer MP9600241

GAPS diving suit FOLEST-GAPS-CARB

GAPS flight case #1 OIGAPS-CASE

GAPS flight case #2 (accessories) OIGAPS-CASE2

GAPS spare hydrophone replacement kit (short leg) OIGAPS-LEG/S

GAPS spare hydrophone replacement kit (long leg) OIGAPS-LEG/L

GAPS receiving hydrophone only 430-3010

(3) Requires external power supply on ECB to operate properly

7.2.2. GAPS services



Designation Ordering code

Offshore field engineer day rate AD OFFSHOREDRATE

Onshore support engineer day rate AD ONSHOREDRATE

Training day rate AD FORMTINE

GAPS, 1 year warranty extension WAREX GAPS



8. Appendix

8.1. GAPS head connector wiring

Pin # signal

GAPS head 16 pin SUBCONN connector Ref J-MCBH16-TIT (male on cable / plug)

Dummy plug P_DLSA-F Locking sleeve P_MCD_16F

1 M Power supply +

2 B Power supply GND

3 C Synchro IN+

4 P Synchro IN-

5 N Synchro OUT – Responder mode +

6 L Synchro OUT – Responder mode -

7 D External pressure sensor RS422 Rx+

8 R External pressure sensor RS422 Rx-

9 E MMI Dialog Input (RS422) Rx+

10 S MMI Dialog Input (RS422) Rx-

11 T MMI Dialog Input (RS422) Tx+

12 J MMI Dialog Input (RS422) Tx-

13 U External GPS input (RS422) Rx+

14 K External GPS input (RS422) Rx-

15 G Standard output (RS422) Tx+

16 H Standard output (RS422) Tx-

8.2. GAPS main cable (50m long)

Ordering code: OIGAPS-JC-MAIN



8.3. GAPS ECB (Easy Connect Box)

Ordering code:

OIGAPS-ECB

1 2 3 4 5 6 7 8 9

Connector #1 Synchro IN (BNC Ref COBNC-F_ISO-PAN) Pin # signal

inner Synchro IN

Outer Ground

Connector #2 Synchro OUT (BNC Ref COBNC-F_ISO-PAN)

Pin # signal

inner Synchro OUT

Outer Ground

Connector #3 External GPS input (DB9 ref CODB9M-SERTIR)

Pin # signal

1 Ground

2 Rx (GPS in)

3 Tx (GPS out)

Connector #4 External Pressure sensor input (DB9 ref CODB9M-SERTIR)

Pin # signal

1 Ground

2 Tx – N/A

3 Rx (Pressure in)

Connector #5 MMI (Man-Machine Interface) (DB9 ref CODB9M-SERTIR)

Pin # signal

1 Ground

2 Tx – N/A

3 Rx (Pressure in)

Connector #6 User position output (DB9 ref CODB9M-SERTIR)

Pin # signal

1 Ground

2 Tx – Transmission to peripheral

3 Rx – Reception from peripheral

Connector #7 GAPS main cable (Souriau J85102E1419P50)



Pin # signal

M Power supply +

B Power supply GND

C Synchro IN+

P Synchro IN-

N Synchro OUT – Responder mode +

L Synchro OUT – Responder mode -

D External pressure sensor RS422 Rx+

R External pressure sensor RS422 Rx-

E MMI Dialog Input (RS422) Rx+

S MMI Dialog Input (RS422) Rx-

T MMI Dialog Input (RS422) Tx+

J MMI Dialog Input (RS422) Tx-

U External GPS input (RS422) Rx+

K External GPS input (RS422) Rx-

G Standard output (RS422) Tx+

H Standard output (RS422) Tx-

Connector #8 Eternal DC power input (Souriau ref J85102E833P50)

Pin # signal

1 +24VDC in

2 Ground

3 Earth

Connector #9 110/220VAC (LFFN9224-6-07)

Pin # signal

P Phase

GND Earth terminal

N Neutral



8.4. GAPS Mechanical interface

8.4.1. GAPS overall dimension

8.4.2. GAPS top bridle drawing





8.5. GAPS transponders / Responders

A wide range of transponder / responder is available for use with GAPS positioning system, ranging from shallow to deep water, with integral or remote transducer head. The most often used versions are shown below only. Refer to dedicated technical documents or to your nearest IXBLUE contact or IXBLUE representative for further details or additional information.

8.5.1. MT912S-R with integral transducer head (405 9115)

8.5.2. MT832E-R with integral transducer head(405 9100)

8.5.3. MT832E-R/HD with remote transducer head (405 9115)

Documents

G_ST_TSH_017B - GAPS