Pixhawk reading invalid roll

I fear my Pixhawk is suffering from some sort of hardware problem :frowning:
Initially all was well with my Tarot 650 quad after installing the Pixhawk. Loiter was rock solid and nothing seemed out of the ordinary. During additional testing however things have been going downhill.
Three times now I have an issue with a similar symptom. The HUD shows the quad rolling grossly when video (and LOS) shows it is not. This weekend I had two instances.

  1. While in land mode the quad was drifting to the right. I added left roll input to counter to no avail. After entering almost full left roll it still was drifting. Upon releasing the stick to center the quad rolled drastically to the right forcing me to take over in stabilize. In Stabilize I was barely able to get the quad back to level using almost full left roll.
  2. On an auto mission the quad got 3/4 of the way to waypoint 2 before stopping. It was directly where it was supposed to be but claimed it was tilted almost all the way to the left (even though video shows it was almost perfectly level). It was as if it was trying as hard as it could (so much that forward progress stopped) to counter-act this imaginary force from the left.
  3. Several times now prearm bad velocity errors have popped up

Here is the mission plan:

Here is what the HUD shows:

Here is a snippet from the video during the time the HUD shows excessive roll:

Here is the snippet where during the auto mission it stopped between waypoints and just sat there struggling. The HUD shows crazy tilt for an extended period.

Please help; I really need to get some work done with this craft but cannot seem to get it to work for me. This is coming on the heels of almost losing it due to a DCM bad heading incident :frowning: I have 2 fixed wing planes with Pixhawk and APM with no issues…this quad is just kicking my butt! If you need any additional info please let me know. Attached is the .tlog file (I have the dataflash logs as well if needed)


Also seeing slow loop lines in dataflash logs (not sure if that is helpful):

Size (kb) 3666.0
No of lines 50288
Duration 0:03:36
Vehicletype ArduCopter
Firmware Version V3.2.1
Firmware Hash 36b405fb
Hardware Type
Free Mem 0
Skipped Lines 0

Test: Autotune = UNKNOWN - No ATUN log data
Test: Balance/Twist = GOOD -
Test: Brownout = GOOD -
Test: Compass = GOOD - mag_field interference within limits (6.52%)

Test: Dupe Log Data = GOOD -
Test: Empty = GOOD -
Test: Event/Failsafe = GOOD -
Test: GPS = GOOD -
Test: IMU Mismatch = GOOD - (Mismatch: 0.51, WARN: 0.75, FAIL: 1.50)
Test: Parameters = GOOD -
Test: PM = FAIL - 20 slow loop lines found, max 11.03% on line 1927
Test: Pitch/Roll = GOOD -
Test: Thrust = GOOD -
Test: VCC = GOOD -


Hmmm…my AccY values are consistently running +/- 13 or so…not so good :frowning: X and Z look good though

Hi. I’m having similar issues. Did you ever get this resolved?

It ended up being a vibration issue…specifically 2 of the ESCs had come loose and were “flopping” when the copter started making large movements.