Hello, I could really use some help getting the configuration right on my quad copter.
It is an EMAX Nighthawk 250 with 2300kV motors, 5x3 props, and a 3S battery. It has a Pixracer running Arducopter 3.4-rc2. I was out tuning it today and I got it to hover very nicely in stabilize mode. I can fly it in all directions and it is quite responsive. However, there is a phenomenon which I cannot figure out how to address. If I fly in stabilized mode
with maximum pitch/roll input in a given direction (e.g. full speed forward) for some distance (e.g. 20 meters) and then center the stick the copter does not return to level immediately. Instead, it pitches all the way to the opposite angle and then returns to level slowly. All this takes a few seconds before it is back to level again. This phenomenon seems to be more pronounced the longer I keep flying in a direction before moving the stick back to neutral.
If someone else showed this to me and asked for my opinion I would say the problem was that some I-gain was too high. It feels like an integral, a moving average, or something else with a time window is building up this counter reaction while I move the copter and then it has to “unlearn” it again before it can return to level. But I didn’t finish tuning the copter today so my I-gains for pitch and roll are 0. Only P and D have nonzero values. Therefore, I’m surprised to see this behavior because I thought that P and D would always result in immediate response, like fast oscillations. I have the feeling there is some PID controller that I’m not aware of (maybe in an outer control loop?) but I can’t find out what parameters are controlling it. Am I totally off or did I just overlook a setting?