MP reports "BAD COMPASS HEALTH"

Ground Control Software Mission Planner
1

Hello,

MP reports “BAD COMPASS HEALTH” every few times I connect. Once it reports that error, the only way I can get the compass to work again is to go into:

I usually need to do that about 3-4 times, then the test will freeze, at which time I can reconnect and everything works sweet again. The lights on the pixhawk go all multicoloured and flashy.

COMPASS_AUTODEC 0 COMPASS_DEC 0.213221 COMPASS_DEV_ID 73225 (0 when error occurs) COMPASS_DEV_ID2 -1 (0 when error occurs) COMPASS_DEV_ID3 0 COMPASS_EXTERNAL 1 COMPASS_LEARN 0 COMPASS_MOT_X 0 COMPASS_MOT_Y 0 COMPASS_MOT_Z 0 COMPASS_MOT2_X 0 COMPASS_MOT2_Y 0 COMPASS_MOT2_Z 0 COMPASS_MOT3_X 0 COMPASS_MOT3_Y 0 COMPASS_MOT3_Z 0 COMPASS_MOTCT 0 COMPASS_OFS_X -122.3317 COMPASS_OFS_Y 78.97478 COMPASS_OFS_Z -72.04604 COMPASS_OFS2_X -245.9847 COMPASS_OFS2_Y -38.45079 COMPASS_OFS2_Z -18.75215 COMPASS_OFS3_X 0 COMPASS_OFS3_Y 0 COMPASS_OFS3_Z 0 COMPASS_ORIENT 2 COMPASS_PRIMARY 0 COMPASS_USE 1

Things I’ve tried so far separately (still came up with “BAD COMPASS HEALTH”):

MAG_ENBALE 0 COMPASS_EXTERNAL 0 AUTODEC 1 COMPASS_PRIMARY 1 COMPASS_USE 0 Re-do compass cal (does not get any readings)

My setup is a Pixhawk on a heli with GPS/MAG kit, powered by 3DR power module. Firmware is 3.2rc3.

What can I do to stop this from happening?

Joly

2

I’ve got an update to this issue. I changed the firmware to 3.15, and noticed the following:

  • Unplug the external compass and the issue continues to occur
  • Plug the external compass back in and I have no issues at all (so far)

When I do CLI > test > compass without the external compass, the compass readings are sometimes >1000. This is because the heli main motor is directly above the Pixhawk.

My theory is that AC3.15 doesn’t care about the internal compass until I unplug the external compass, so MP wont throw “BAD COMPASS HEALTH” until its using the internal compass. AC3.2rc3 does use both, so I get the error regardless.

I’ll report this to the devs, hopefully they can confirm.

3

Started having this issue today, updated to AC3.2-RC12. Bad Compass Health notice on HUD.

I’m using a APM 1.6 clone board with the internal compass trace cut and a NEO-6M GPS/compass, had calibrated compass without issue on AC3.1.5. Tried re-saving compass options, no luck so far. Compass is incrementing 1 degree/second.

4

Yeah my NEO-6M was toast, the internal connector had come loose from the uBlox chip, it’s an RMA job, switching to another GPS/compass combo fixed this issue.