I've put together a new scratch build and was running Autotune on it yesterday. Had Autotune OFF at the time. Quad started slowly rotating about the vertical axis while flying. Did a rough, (but not too rough) landing, pulled all motors and re-secured them to to the arms confirming that they were not askew. Tested it and still had the yaw. Calibrated my ESCs, flew it and still had the yaw. Finally swapped in a known good 3DR compass + GPS, then recalibrated compass, accel, and level. Craft still is wonky about the vertical axis. Quad is a Murray Spoelstra based design with 15" props and RCTimer 5010-360 motors. Pixhawk is one of the new Mayan Robotics units. Pids are as follows: Roll - 4.32, P=0.19, I=0.19, D=0.0036...Pitch is same as Roll, Yaw is 4.5, P=0.220, I=0.020, D=0.003.
Question(s): Do the yaw PIDS seem reasonable? What else could this be? TIA...
Replies
Got it. #3 motor had a very slight tilt associated with it, (~2 or 3 degrees) . Swapped this arm with a spare and the problem was resolved.
In midflight the yaw misbehavior started. Had been running Autotune doing roll axis adjustments. I don't believe that it had progressed to the yaw Autotune..
It was fine before what happened?