Accelerometer Calibration

[realtimepeople]

In has been observed that the accelerometers of the Mti1 are not precisely calibrated.
Offset and gain vary by some 1-2%. At least for the channel(s) that are used
for the aircraft's down axis a calibration will give some improvement for the
AHRS and the variometer.

The calibration can probably only be done manually on the ground.

We shall add a possibility to calibrate the accelerometers similar to the magnetic calibration.