iXBlue GAPS User manual

GAPS
Positioning System
QUICKSTARTGUIDE

Conventions
The following conventions are used in this guide:
bold Bold text is used for items you must select or click in the software.
Courier Text in this font denotes text or characters that you should enter from the keyboard, the proper names of
disk Drives, paths, directories, programs, functions, file names and extensions.
italic Italic text indicates the result of an action in the procedures.
GAPS System Overview
The Global Acoustic Positioning System GAPS is a portable Ultra Short Base Line (USBL) with integrated Inertial
Navigation System (INS).
The GAPS system is recommended for mobile or fixed installations. It can be combined with an additional hoisting
system. It is a plug & play installation and calibration is required neither before using it nor after reinstalling it.
The operation principle is based on a bi-directional exchange of underwater acoustic signals between the acoustic
transponders and the GAPS unit that comprises one transducer for transmitting and four reception hydrophones.
Verification of Pack Contents
You will find in the shipping case a Packing List detailing all the items delivered. This packing has been completed and
checked by iXblue before shipment.
We recommend that you check the contents of the pack and the equipment immediately on receipt of your GAPS unit.
Specifically, you should check that all the items referred to above are present on delivery and that none has sustained
damage.
If you observe any non-conformity or damage, please inform the carrier and iXblue without delay by certified mail,
describing in detail the problem encountered.
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Install and Connect GAPS
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Install and Connect GAPS - Steps in Details
1. Install the GAPS acoustic antenna (User Guide - section 3.2)
●Set up GAPS on the ship. GAPS may be held by a rope, fixed on a pole or fastened below the keel. Place the
hydrophone H1 towards the bow. Do not forget to remove the protection caps from the four hydrophones. Make
sure GAPS is at least 1 m away from any reflective surface.
●If you use the optional iXblue DGPS: connect the Y-cable to the antenna and then connect both the 10 m GPS
cable and 50 m antenna cable to both ends of the Y-cable.
●If you use an external GPS: do not install the Y-cable. Connect the 50 m cable on the GAPS.
Note: It is your responsibility to minimize the potential differences between the GAPS antenna and the vessel. The
GAPS unit must benefit from the electrolytic protection of the vessel.
2. Connect the BOX (User Guide - section 3.3)
Connect the 50 m antenna cable to the corresponding SOURIAU 23 pins GAPS plug.
Power Supply: either 24 - 36 VDC or standard 100 - 240 VAC.
Four input/output Serial A, B, C and D DB9:
●Input your own GPS
●Input the optional pressure sensor
●Output position toward an external navigation software
The BOX is connected to the Ethernet network of the ship via the Ethernet plug. Four input and output Ethernet links
are available.
3. Install the GPS antenna (User Guide - section 3.4)
There are two different ways to install the GPS antenna with consequences on GAPS mounting:
GPS antenna right above GAPS:
●With a rigid link: this is typically when GAPS is mounted on a pole. When GAPS is vertical, all the offsets
between the GPS antenna and the acoustic array are set to 0 except the height which must be entered accurately
in order for the system to calculate the GPS position offset when the system attitude changes.
●Without a rigid link: this is typically when GAPS is held by a rope. In that case, the height value is set to 0 (to
avoid the calculation of the offset). The accuracy of the positioning decreases if the position of GAPS relative to
the GPS antenna changes.
GPS antenna not exactly above GAPS:
In this case you measure the three lever arms (precision 10 cm) of the DGPS reference point with respect to the
reference frame based on the center of the GAPS antenna top flange. No matter if the heading, roll or/and pitch are
not the same than the heading, roll or/and pitch of the ship (yet it has to be taken into account if GAPS is also used as
an onboard gyrocompass), but these values must be known and will have to be inserted in the Web-based User
Interface in order to calculate the position of the GPS in the GAPS reference frame.
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Configure the System
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Configure the System - Steps in Details
4. Configure the System
- Network (User Guide - section 4.2)
Connect the computer to the BOX via the Ethernet link. Configure the GAPS in two steps:
●Connect the BOX directly to the computer with a crossover Ethernet cable.
●Configure the network settings (IP Address and Net Mask) of the computer to be able to communicate with the
GAPS. Make sure to be on the same domain than GAPS.
●Open a browser (GAPS Web-based User Interface is optimized and qualified for Firefox) and enter the IP
address of GAPS by default http://192.168.36.1xx (xx being the serial number), default subnet mask
255.255.255.0.
>For products delivered before 30 April 2016, the default IP address is https://192.168.64.19.
>If you do not know the IP address, connect a HyperTerminal (115200 bps, 8, none, 1) on one of the RS232
plug and the current IP address of GAPS is then broadcasted.
●Username: admin, password: admXI
●Under INSTALLATION menu, select NETWORK and set up the GAPS network settings in accordance to the
network of the vessel and connect the BOX to the network of the vessel via a switch.
– Mechanical parameters (User Guide - section 4.3)
Under INSTALLATION, select MECHANICAL PARAMETERS and enter:
●The Misalignments (Roll, Pitch and Heading) of the antenna with respect to the vessel reference frame (they are
set to 0, 0, 0 by default)
●The GAPS Depth distance of the average sea surface with respect to the GAPS.
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Configure the Data Flow
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Configure the Data Flow - Steps in Details
5. Configure the Data Flow (User Guide - section 4.4)
Four serial and four Ethernet ports are available for the input and output of data from and to external sensors or
devices.
– Input Settings
Position ,UTC ,Pressure ,Telemetry and Hoisting System data can be input into the BOX. Under
INSTALLATION menu, choose INPUTS and select the connection parameters corresponding to the input data. For
Position,UTC,Pressure,Telemetry and Hoisting System configure the Port,Protocol and Serial or Ethernet
parameters. For Position, configure the Lever Arms if not already corrected in the motion sensor.
Select Embedded for the Port of the GPS if you use the iXblue GPS.
– Output Settings
Under INSTALLATION menu, choose OUTPUTS and select the Port, the Protocol (and Frequency) and the
Ethernet or Serial port parameters.
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Configure the Survey
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Configure the Survey - Steps in Details
6. Configure the Survey (User Guide - section 5)
– Under SETUP menu, choose TRACKING and select the Synchro Mode and the Recurrence. Select either
Internal or External synchro mode and enter a value of recurrence. Several examples of configuration are provided in
page 12.
– Under SETUP menu, select TRANSPONDERS, add new transponders and configure them. Enter in the
database the transponders that you are planning to use. Click on Change Settings to configure the transponder:
●Configure the transponders Interrogation mode (Transponder,Responder Main,Responder Sec.) and code
(tonal or MFSK).
●Configure the transponders Reply code and Turn Around Time.
●Add optional Additional Information (External Pressure or Fixed Depth).
●Configure the optional Dynamic Positioning parameters (mode L/USBL or L/USBL/INS , fixed position,
reference transponder).
●Set up an optional type of Filter depending of the use of the transponder (Mobile or Fixed).
●Enter a Label to identify the transponder and possible Repetition Factor.
●Click OK to validate the configuration and to go back to the list of transponders.
●Activate the transponders to be used by setting the switch to ON.
– Under SETUP menu, select SOUND VELOCITY PROFILE and enter a sound velocity data. If you have a
sound velocity profile of the survey area, enter this profile manually or load the data file.
– Under SETUP menu, select SETTINGS MANAGEMENT and enter a text file name in which you can save
the settings already entered. You can also restore some product settings previously saved.
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Configure the Data Logging andStart the Survey
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Configure the Data Logging andStart the Survey - Steps in Details
7. Configure Data Logging in iXblue Multilogger, watch the flow (User Guide - section 9.3.6)
●Run through the general configuration, click on the Configuration button.
●Click on the data flow specific Configuration button (repeater log, TCP connection port 8210).
●Click on the Start button and select the flow to start.
●Click on the View button and check the Settings,Status and Flow log history.
8. Start and Control the Survey (User Guide - section 9.2)
– Click on Start Tracking to initiate the positioning. Use iXblue Multilogger for data logging.
– Click on navigation data to open the navigation data window that displays in real -time a large set of data from
the system.
– Click on Control to display the status of the various part of the positioning system. Click on TOOLS
>SPECTRUM to control the operating state of the four hydrophones via a frequency graph for each hydrophone.
– Perform the alignment of the INS: coarse (GAPS ready for navigation) and fine (accuracy improvement)
alignments:
●Coarse alignment: leave the vessel adrift for 5 minutes with no accelerations
●Fine alignment: sail in a “staircase” way during 20 minutes
9. Recover the Transponders (User Guide - section 9.4)
Select the TOOLS > TELECOMMAND menu.
Select the Bit0,Bit1 and CAF codes.
Select the ARM and the Release CMD codes and the Acknowledge Timeout.
Click on Send
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Example of Blanking Time and Recurrence Configuration
(User Guide - appendix E)
GAPS with Beacon(s) Settings Blanking time with
Recurrence 1 s
Blanking time with
Recurrence 2 s
Blanking time with
Recurrence 4 s
1 beacon Int. F1 / 22 / TAT 90 800 ms 1800 ms 3800 ms
2 beacons* Int. F1 / 22 / TAT 90
Int. F2 / 22 / TAT 90 1800 ms 3800 ms 7800 ms
2 beacons** Int. F1 / 22 / TAT 90
Int. F1 / 23 / TAT 90 800 ms 1800 ms 3800 ms
3 beacons
Int. F1 / 22 / TAT 90
Int. F2 / 22 / TAT 90
Int. F3 / 22 / TAT 90
2800 ms 5800 ms 11800 ms
4 beacons
Int. F1 / 22 / TAT 90
Int. F2 / 22 / TAT 90
Int. F3 / 22 / TAT 90
Int. F4 / 22 / TAT 90
3800 ms 7800 ms 15800 ms
* Priority to positioning accuracy vs update rate
** Priority to update rate vs positioning accuracy
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Operational Check List
Check that H1 hydrophone is oriented towards the bow.
Check that the deck cable is running on a safe way for people and cable when going out of the pole and on deck.
Measure the offsets between the GAPS reference point (connector) in operational position and the GPS antenna.
Check the power supplied to the GAPS BOX (28/36 VDC or 220 VAC).
Check that you have removed the hydrophones protective caps.
Connect the computer and turn the GAPS BOX on. Run GAPS Web-Based User Interface. Check communication.
Check that the GAPS heading is similar to the vessel heading.
Configure Recurrence: take care of the distance GAPS – Transponder (1 s for a range of 750 m maximum).
Configure Blanking Time: depends of the recurrence and the number of different interrogation frequencies used.
Configure the Turn Around Time: 90 ms most of the time, 20 ms in deep water.
When opening the transponders for configuration, check that the O-rings are clean (dust, hair).
Check battery level of the transponders (switch on Test, time (1 to 6 s) between two pings).
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IXBLUE CONTACT - SALES
North America /NORAM
[phone] / [phone]
iXblue Defense Systems, Inc
27 Wellington Road,
Lincoln, RI 02865 USA
[phone] / [phone]
iXblue Inc.
1580 Lincoln Street, Suite 860,
Denver, CO 80203, USA
Europe Middle-East Africa
Latin-America / EMEA-LATAM
[phone]
iXblue SAS France
34, rue de la Croix de Fer, CS 70121,
78100 Saint-Germain-en-Laye, Cedex, France
Offices: Dubai, Germany, Netherlands,
Norway, UK
Asia Pacific /APAC
[phone]
iXblue Pte Limited Singapore
15A Changi Business Park Central, 1
Eightrium #04-02, Singapore, 486035
Offices: Australia, China, India
IXBLUECONTACT - SUPPORT
For non-emergency support
[e-mail]
For genuine emergencies only
North America / NORAM
[phone]
Europe Middle-East Africa
Latin-America /EMEA-LATAM
[phone]
Asia Pacific / APAC
[phone]