Hi all
I am building a new quadcopter, using PX4 and rotor, ESC from 3DR
I have a problem relating to PID tunning. I am using Mission Planner >>Config/Tuning>>Extended Param to send my values to my Drone
This is what I am doing:
First, I follow this guide to find a P value: http://copter.ardupilot.com/wiki/ac_rollpitchtuning/
Second, when the Drone oscillates, I can find the Tu, and try to apply Ziegler Nichols method (https://en.wikipedia.org/wiki/Ziegler%E2%80%93Nichols_method) to find I, D values for both Roll&Pitch
Results are not as good as what I want, in Pitch axis, my Drone always be skewed
If anyone solved this problem or another solution, please help me
Thank you very much
Replies
Continue to use the method you are currently using to find the P value just before oscillation and then back it off a little bit. Once you have found that, slightly raise the D term you reach an oscillating state and then lower it. At this time it should be controllable to move to outside testing. If you can achieve a stable hover trying use Autotune from here. If you get oscillations at takeoff lower your P value slightly and try again. The bench testing method will only get you in the ballpark. in flight tuning / autotune will get you the rest of the way.
I added the video I tested on Youtube : https://www.youtube.com/watch?v=RhTdd01-2KU