OXTS xNAV650, Руководство по оборудованию

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Best practices
Mounting
It is essential to mount the xNAV650 rigidly in the vehicle. The xNAV650 should not be able to move or
rotate compared to the GNSS antennas, otherwise the performance will be reduced. In most
circumstances the xNAV650 should be mounted directly to the chassis of the vehicle. If the vehicle
experiences high shocks, then vibration mounts may be required.
Figure 8 shows the mounting points for the XNAV650. The mounting holes are suitable for M3 threaded
screws.
Figure 8: xNAV650 mounting points (mm)
Do not install the xNAV650 where it is in direct sunlight as this may cause the case to exceed the
maximum temperature specification.
Orientation and alignment
The orientation of the xNAV650 in the vehicle is normally specified using three consecutive rotations
that transform the system to the vehicle’s co-ordinate frame. Refer to Figure 4 for directions of axes.
The order of the rotations is:
o
Heading (z-axis rotation);
o
then pitch (y-axis rotation);
o
then roll (x-axis rotation).
It is important to get the order of the rotations correct or the transformation may not apply correctly.
The xNAV650 can be mounted at any angle in the vehicle as long as the orientation is described in the
configuration. This allows the outputs to be rotated based on the settings entered to transform the
measurements to the vehicle frame.