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5 08-Apr-2016, 12:30 AM (This post was last modified: 08-Apr-2016, 12:31 AM by fpvmonkey.) Tuning question of the day.
What is the correct way to eliminate prop wash oscillation on descent or hard turns?
What PID should I adjust?
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5 08-Apr-2016, 12:34 AM (This post was last modified: 09-Apr-2016, 12:43 PM by Multirotor Army.) Prop wash can be reduced by using a flying technique commonly taught to full size helicopter pilots, as known as "nose dive" - avoid descending in a straight downward line, instead try to always have some horizontal speed. This causes the copter to constantly move away from propwash.
We crashed our faculty drone because we don't remembered this (it was quite underpowered and could not fight the wash with raw power).
Regarding propwash in a sharp turn, you seem to be turning with a higher G force than your motors can provide, hence the copter is "descending", albeit sideways into the propwash. Again, try to have as much forward speed as possible during sharp turns, for the same reason as above. Hope this helps
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0 I agree with the above as a better way to fly, but you should also be able to tune most (if not all ) of it out.
It's hard to say definitively without seeing your config, but TYPICALLY bumping up I just a little bit, corrects the issue.
You first need to determine which axis is wobbling. Watch you copter to see if it's wobbling left to right or front to back, then try bumping up I on that axis. If your I is tuned good to start with, then you should only need a very little bit of an increase. You don't want to over tune I.
As an example, I had this problem when descending through prop wash on one of my older copters. My roll I value was 0.035. I increased it to 0.036 then 0.037, and finally landed on 0.038. After that, I only saw the wobble in very rare cases.
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