I just bought a Pixhawk kit from mRobotics, my 2nd one from them. It comes with their Ublox GPS/compass unit as well. I have the Pixhawk and GPS/compass unit taped to a piece of cardboard to maintain their orientations for bench testing.
The compass calibration seems to go okay, although the numbers seem high. I tried both the onboard and live calibrations with similar results.
After the calibration, I’m still getting a lot of “Inconsistent Compasses” and “Compass Variance” errors.
I can load the EKF status window and slowly yaw the system and watch the compass EKF go off the chart relatively quickly.
The offsets of your compass are too high.
- Try Onboard Mag calibration
- Disable Internal Compass
If this will not solve the problem you might have a problem with the I2C bus .
What is the batch of you Mrobotics Pixhawk (it is written on the PCB ) ?
Had this same problem today.
Turning off internal compass completely fixed it.
But is it a good idea to disable them?
I mean aren’t internal compasses designed to be back up?
Not really , since internal compass is widely unreliable it often gives readings that are contradictories compared to the one of the external compass .
The point is that if the difference between the two compasses becomes too big , then, EKF do not know which compass is right and so it display an error