Hi everyone. My quad is behaving very strangely. The quad is set up pixhawk 2. Yesterday, when I was doing an autotune, everything was ok. Today I took off and the drone falls into a dangerous oscillation. I do not know where to look for the cause. Is it PIDS fault. Can anyone look at the logs and parameters?
https://drive.google.com/drive/folders/1DGlbfRCSml_MlmC_hOXUdScg8l6BeUlj?usp=sharing
I haven’t looked at your logs, but I would guess your auto tune completed when the battery was getting flat. Therefore the gains are to high when a fresh battery is fitted. You should turn on voltage scaling of PIDs and redo the auto tune.
The auto tune was turned on with the battery full. Due to the fact that the quad weighs only a single axis only slightly. I started with ROLL, then I recharged the battery and again I did PITCH. I forgot to add (because it may be important) propellers are 26x8.5, and MAD8108 170KV motors.
For such a large quad you may want to lower the Rate pitch and roll filters to 10Hz and run autotune again.
Today it was completely windless and I decided to repeat the auto tune. Earlier, I did voltage scaling and decreased the pitch and roll filters to 10Hz, and also decreased AUTOTUNE_AGGR from 0.1 to 0.050. I picked up the drone and turned on the auto tune. The drone only made one move back and lost its stability completely. It thrashed like a wild pig and crashed. Would not it be better to do manual PIDS? Probably safer? Honestly, I did not expect such a reaction from the quad.