IMU magnetometer calibration

[DrWino]

I have been successful in making an ethernet imu server using red brick+imu 2.0 + ethernet POE brick. Works really great ! Thanks. My question is how to calibrate the compass to take care of metal disturbances and EMF caused by the vehicle ? How good is the imu with vibration ?

[borg]

You can't do any more than to use the provided calibration function. If the changes of the magnetic field are too big for the IMU to cope, you can try to used the sensor fusion mode with magnetometer (see set_sensor_fusion_mode in the API).

 

In this mode the magnetometer is not used and thus can't contribute false readings. However, in this mode you can't of course use the IMU to calculate absolute heading (since the magnetometer is necessary for that)!

[DrWino]

Interesting. I can provide absolute heading by dual RTK-GPS so perhaps it might be better to not use the magnetometer at all but use this absolute heading periodically to adjust the imu. If you have and ideas or example code I would be grateful. I will look at the API and see how it works. On another note - what is the minimum voltage acceptable to power the ethernet POE ? It needs to support this + red brick + imu. Thanks.