Heli flying with PID values where d=0

Hi all, I’ve setup an electric heli like a 500 size and it is flying well. Indeed it is able to fly even automated missions. My question is related with the fact of having D values for Pitch and Roll at 0. When I try to increase any of those values at 0.001 it start to oscillate quite a lot, but with this value at 0 it flies I would say quite well.

Anyone could tell me a way in order to try to increase that value?. I think it could perform better if I could increase slightly that values.

Roll Pitch

P=0.036 P=0.050
I=0.061 I=0.069
D=0.000 D=0.000

Thank you in advance.

Julio.

Julio,
The current firmware prematurely limits the tuning of the PID controller. Instead of your I term being so high, it is more desirable to have your P term around 0.2 and if possible your D term at some low value (approximately 0.003). Unfortunately these values can’t be reached because of the Heli instabilities. See my post on Technique to expand roll and pitch rate PID gains without instabilities. This describes how you could use the filter to get a little more out of the P and D gains but ultimately a notch filter is needed to filter out the instability frequency.
Respectfully,
Bill

Thank you very much Bill for your response, I should add I’m using firmware version 3.3.3. I will review your post.

Kind regards,

Julio.

IIRC I used Full Parameter List/Tree xxx_D = 0 to 0.0005 on one heli. looked better, but … Bill knows better :slight_smile: