I am using MATLAB Simulink's toolbox for Parrot Minidrones, which have an ultrasound an optical flow sensor built-in. Whenever I am trying to let the drone hover in position, it drifts into one direction (always the same direction). The strange thing is that the drone knows it is drifting, but nothing is happening to correct it:
The drift only seems to occur horizontally, vertically the drone is not drifting. An overview of the relevant part of the PID implementation can be found here. I have tried tweaking some values, but it does not seem to improve. Does anyone have any tips for what the issue might be?
Edit: graph of roll, pitch & yaw