Yesterday I was doing a second flight with a new quadrotor frame and had a rather ok loiter for stock pid settings. For about 13 minutes loitering went very well but then the quadrotor started rotating in air and I had to bring it down manually.
For some reason I see yaw input pulsating when I was not touching any levers of the RC control. As can be seen from the log, the yaw output is not as it looks like when I am actually controlling the quad.
Could anyone help me tracking this problem down? I will have new long loiter test today, but I need to find out the reason for this kind of behavior.
The frame is custom made foldable Carbon Fiber. Using Arducopter 2.8.1, 10Ah battery and AVROTO motors.