Navsight Solution
– Hardware Manual
NAVSIGHTHM.1.5
2.2.2.4. Subsea form factor
The Apogee Subsea IMU enclosure is composed of titanium parts, one for
the cover and one for the base plate. The device uses high quality
connectors to offer a depth rating of 200 m and good resistance to
seawater environment.
Mechanical alignment
For best measurement accuracy, a good mechanical alignment is required.
During manufacturing, the Apogee IMU frame has been carefully aligned
to 0.02° with the base plate for roll, pitch and yaw angles.
To ease the yaw alignment (X axis), the base plate features two alignment
holes Ø 4 mm H8 that guarantees with two taper pins Ø 4 mm h7 a yaw
alignment better than ±0.04°.
Origin of measurements
The Apogee IMU offers the possibility to output data at different measurement points.
The default center of measurement is located on top of Apogee enclosure, on the coordinate frame center
drawing. It is represented on the mechanical outlines by the symbol. It is defined to simplify installation.
Alternatively, user can select between two other center of measurement points:
●
Alignment hole (aligned to the bottom of the base plate)
●
Bare IMU center of measurement, represented by the symbol.
Specifications
Electrical and Mechanical Specifications
Enclosure materials
Titanium
Dimensions
Ø 9.2 x 17.75 cm
Weight in air
1.32 kg
Weight in water
0.98 kg
Input power voltage
12 – 36 V DC – isolated power supply
Power consumption
2.5 W typical.
Environmental specifications
Depth rating
200 m
Humidity
Sealed, no limit
Operating Temperature
range
-20°C to 60°C – specified range
-40°C to 71°C – operating range
Storage Temperature range
-40°C to 85°C
Shocks
500 g for 0.3 ms
Operating Vibrations
3 g RMS – 20 Hz to 2 kHz as per MIL-STD-810G (A2 range options)
MTBF
50.000 hours
Calibration interval
None required, maintenance free
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Figure 2.6: Apogee Subsea IMU
