Truly just another vibrations issue?

I’ve got a pixhawk running 3.2.1 on a Skyhero in a Y6b configuration. During a flight this morning, I was flying in loiter, and the drone started climbing suddenly (not too fast, fortunately). When I decreased the throttle, it did start to descend, but very slowly. Not nearly the 2.5m/s it is supposed to when throttle in is at 0. I suspected a vibrations issue, and this was indeed confirmed by the logs (though the z-vibrations don’t appear too far out of the ordinary).

What confuses me is the poor altitude tracking. Prior to the increase in z-vibrations, the altitude tracking was ok, however once the vibrations started it degraded significantly. Do vibrations explain this? If so, how? If not, what else could be causing this behavior? Another strange element is; before the vibrations ensue, the drone begins to climb ahead of the desired altitude…


With high vibration the altitude estimator get messed up. Switching to stabilize will give you back control. The vertical movements make the quad look like it’s moving up and down, so the estimator is trying to compensate.