First flight Tailsitter. Unstable Hover, video and logs

Hi, After some initial testflight i’m unsure how to continue to make the tailsitter more stable in Rotor mode.
I suspect the model is a bit unbalanced and that’s why the pitch is acting up. Also the controller might be to aggressive?

  • STABILIZED mode without GPS. I recall that the tailsitter will tip over unless you give enough throttle and pitch during takeoff. Movie: stabilized mode .

  • Takeoff and Land, b arely holding on and loads of oscillation occurs. TakeOff and Landing. With the loggand logfile: logfile.

Hi, there are definitely some very heavy oscillations in your pitch. I can see that two of your motors keep oscillating and repeatedly hits upper saturation. This normally indicates that your controller is too aggressive as you also suggested yourself.
I would try and reduce the P and D gain of the pitch rate controller to see if that can help.

I’m a bit surprised you can actually fly it with how much it oscillates.

Thanks for the replay!

Well, Today I tried to do some tuning but manage to crash enough for some TLC. Here is the log file crash. This was in altitude mode… It’s just to unstable to be able to tune it and flying at the same time.

I have access to a lab with a high ceiling. I’m thinking of building a frame with bungeecoords that supports the wing when i tune it. I figured that if i manage to hover good with some tension it’s good enough for outside testing.

Sorry to hear about your crash. Your drone looks to be better tuned, even though it is still not perfect. The main problem is that your elevons keep going from max to minimum saturation constantly, which suggests some problems with the tuning still. Unfortunately, I don’t have any experience tuning a tailsitter, so can’t help you a lot, but sounds like a good idea to tune it in the structure to avoid crashing the drone.

Hope you manage to get it flying. If you need more help, I would suggest asking on the discord, where you can contact the developers.