Understanding Log Help with rll_axis shaking

ArduCopter Traditional Helicopter
1

Hi Community!
Finaly I did my maiden! Whoop Whoop!
I noticed very hard fast shaking over roll axis. Now I want to solve this.
I need your help understanding my Log Data.
First thing: testing FC vibrations on ground during idle up and stable head rpm there was such no ekf warning or FC vibration.
During maiden i noticed stable head in lift off but within seconds the frame is oscillating over roll axis! Unable to fly.
I paste the Log link:

https://drive.google.com/file/d/1bkEHS_Pn1l67n3YWeD0EixRXPo-_mDCT/view?usp=sharing

2

I haven’t looked at you log but from what you described it is probably that ATC_RAT_RLL_P or ATC_RAT_RLL_D gain is too high. You could cut them in half and try flying again. Are you using the default gains or did you load or change the gains. I will try to look at your log today.

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3

Thank you Bill!! I will check the values! Hope to hear from you later!

4

ATC_RAD_RLL_D is set to 0.001000
ATC_RAD_RLL_P is set to 0.080000

5

Yes it depends on the size of the heli but I would say that these gains are too high.

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6

Ok…
Any advice for me? It’s 700 Gasser. Is it possible that ATC_RAT_RLL_D limited to minimum 0.001000?
Thank you for your time Bill!

7

I requested access to your the file you posted. Well the minimum for the D gain is zero. So you can make it 0.0001 if you want

8

Oh thats my fault! Sorry @bnsgeyer
This Link should work now!

https://drive.google.com/file/d/1bkEHS_Pn1l67n3YWeD0EixRXPo-_mDCT/view?usp=sharing

9

This maybe stubid question but is it naccesary what MP I did use for FC setup?
At least I used QGround. Should I better use Missionplanner?

10

Either is ground station software is fine.

Looking at your log, it is definitely due to the P or D gain. Did you follow the tuning guide to tune your heli? Follow the guide to set these gains and the VFF gain.

11

I follow the Setup by Chris Olsen on YouTube and used the Tuning Guide you´ve send.
As I read in another Thread you had answerd the other day I set the VFF to 0.08.
The Guide say increase the Gain till Frame is start to shake and cut in half the last value.

12

Follow the tuning guide in setting up the VFF gain. This could be quite different between aircraft, even similarly size aircraft.

Correct, but it appears that you are still having oscillations so you will need to redo that part of the tuning. My guess would be that your P gain is too high.

13

Thank you @bnsgeyer I’ll give it a try! Unfortunately it’s bad weather outside.
Thank you for your time and the knowledge you share!