I-Value

Hi,

I’ve read only reason for unflightable copter (heavy wobbling, flipover) with standard params (out of the box) must be a hardware misconfiguration. After I’ve rechecked everything again and again, I began to adjust the PID gains. I’ve just set the I-Value to 0.08 (from 0.1) and the copter hovered ike a charm without any wobbling. Does someone have an explanation why such a slight change can have such a strong effect while other similar setups I’ve used worked with any change of the I-gain? Maybe the arm length I’ve almost doubled? Or the props which could be a slightly bit oversized for the motors which should affect the time of speed changes?

Best, Bjoern

bjoern79de,
Well, that is a very slight change so I’m also surprised that it makes such a difference. the I term is usually such a slow acting gain that it normally doesn’t matter all that much. The P and D are the big ones normally.
Sorry I can’t be of more help.

bjoern: I would suspect what you are observing is a symptom of the P terms being really far from where they need to be. I’m quite experienced with PID tuning, and there’s no good reason why a small change to I-term like that would cause or solve a flipping over problem. The only explanation I have would be that your P term is way too low, and you are flying purely on I-term, and then this would only work for hovering in a windless environment.

Do you have a log?