700 size instability

I have just started flying a KDS 700 Innova v2 with a Pixhawk 2.4.8 with recent FW. Low weight / head speed (1020rpm) set-up

It flies, but is not stable and seems to be toilet bowling at pos hold even if the compass seems OK.

The yaw is also unstable, with a oscillations/overshoot. I have tried reduce P and increase D but with little effect.

Log file from above flight [HERE] - comments and suggestions very welcome.

@mike_o Check the link you provided for the log. It is a log for a plane.

Bill, thanks. I fixed the link (and THIS is the file).

Hi Mike,
You need to remove the vibrations from the rotorhead using the Harmonic Notch. The wiki on it is here. Then you need to follow the tuning guide here. I would suggest that you change your LOG_BITMASK so that it includes PID and FAST_ATTITUDE in addition to the default selections. If you have questions or need a little assistance, post your questions on this thread.
I would like you to work through the wiki’s first to do the tuning. I’d rather you come to me with a few pointed questions. I am trying to make tuning easier with an autotune feature. Hopefully it will be out in the next 6 months.

Bill, thanks a lot. I will go through the Wiki again and more throuroughly :wink:


Hy Bill, do we realy have to wait 6 more months for autotune? I cross fingers for shorter time.



@heri Heri,
Well it will take some time for me to get it reviewed and ready for beta release. I hope this next round of alpha level testing with users will go smoothly. I think I have a good sense of what is necessary for a good heli tune. If you want to get involved with the alpha level testing let me know.