Introduction - APPLIED ACOUSTICS Easytrak Alpha 2665 Series Operation Manual

2665 Series Operation Manual
EZT-2665-8000/6
1. I
NTRODUCTION TO THE
This manual provides the user with information on the installation, operation and
maintenance of the 2665 Easytrak Alpha Ultra-Short Base Line (USBL) underwater
acoustic positioning system.
USBL systems are used to position underwater items including Side Scan Sonars
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ROVs , AUVs
With no compass input, a position will be SHIP (bow) referenced, e.g. 123m 'X'
means 123m from the starboard side of the ship, whereas, with a compass, a
position would be NORTH referenced; 123m 'X' means 123m from the ship East.
A position can either be 'relative' for example 123m 'X' and 234m 'Y' from the ship,
or 'absolute' for example 412789m East, 5823456m North, if a GPS receiver and
compass is enabled.
Easytrak Alpha has been designed so that it requires the minimum of user
intervention; the system can be ranging to beacons as soon as the transducer
enters the water. The current set–up is automatically saved on program power-
down allowing a quick resumption of work on the next power-up.
The display not only gives positioning data in text form, but also graphically.
Beacons are individually identified and colour-coded,
ORANGE – caution, prediction being used, and
predict safely.
Because of multi-path reflections and other types of acoustic interference, the
position can occasionally be corrupted. In smoothing mode, Easytrak Alpha has the
facility to 'gate-out' wild values of velocity. The 'out of gate' positions are replaced
by predicted values. Note the compass must be enabled.
The Easytrak Alpha transducer is fitted with internal compass, pitch and roll
sensors. The pitch and roll sensors work to ± 80°, more than sufficient for boat
work.
Note: Strong magnetic anomalies can be beyond the calibration range of the internal compass. It is
advisable, that a bearing check be performed prior to use.
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Sonar system for seabed mapping
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Remotely Operated Vehicle
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Autonomous Underwater Vehicle
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2665 E
ASYTRAK
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, and divers.
A
LPHA
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GREEN – position OK,
RED – signal lost and cannot
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