This is a quadcopter using ArduPilot 4.5 with 24” propellers. I was testing the mode transitions between stabilize and PosHold, and upon transitioning from PosHold to stabilize I lost control of the heading and basically forced it to land, miraculously without damage. I attached a picture showing the EKF_STATUS_REPORT.compass_variance vs time: the last transition event from PosHold to stabilize was the point where I lost control. The full logs are also attached. I understand that PosHold mode relies on GPS and magnetometer, while stabilize mode doesn’t use either… but I really don’t know what’s going on here or how to rectify it. Any input is much appreciated.
Edit: forgot to mention that I am only using the external compass (Here 4 CAN GPS/Magnetometer), with the compass internal to the Pixhawk Cube Orange FC being disabled since I was having compass issues (“compasses inconsistent”) prior to this incident when both compasses were enabled. I attached the picture of the compass setup from the Mission Planner screen, for completeness. I had done a fresh compass calibration outside prior to this loss of yaw control issue because the issue happened before and I thought a compass recalibration would do the trick… but unfortunately it did not.
