Re: GPS assist and Heli
« Reply #195 on: January 12, 2019, 09:19:15 am »
Can I change this PIDs somehow, I tried but if turned them down it will be hard to control since it does not respond.
Only adjust the normal (Stabilization page) PIDs when flying Attitude or Rate mode, not GPS modes.  And adjust them for best operation.  Then adjust the VTOLPF PIDs, but only when flying GPS modes like PH or VR.

Maybe add a real Fly bar?
That should not help anything.  And it would only slow down the response and potentially make it toilet bowl worse I suspect.

Or maybe reconsider the load of GoPro and gimbal and big lipo ...
If it carries it in Attitude mode, it should be possible to make it carry it in GPS modes.

I did tweet a lot with the HorizontalVelPID, Kp and Ki but that had the limited effect that it only delayed the time when the toilet bows started a little. I tuned them down from 8.0 to 0.00008 :)
8.0 to 0.00008 with minimal effect means that setting is not affecting it.  Some of the settings work in this GPS mode and some in that GPS mode.  Example: I recall VelocityRoam has a separate set of PIDs.  Generally VR and PH use the same code.  They may or may not use the same PIDs.

What do you think about working on the HorizontalPosP, now at 0,25?
That is a logical one to try.  I would try all the logical ones...  :)


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Re: GPS assist and Heli
« Reply #196 on: January 14, 2019, 08:32:38 am »
Thanks. It makes sense.
I think know what to try next.
Unfortunately, will not be able to get down to south of china and try it until march though  :'(

Re: GPS assist and Heli
« Reply #197 on: January 14, 2019, 10:54:37 am »
I don't much like that CPU error.  There is an "Update Period" setting in VTOLPF.  I would be tempted to increase it till the CPU error went away.  Of course I haven't tested that myself, so be ready to switch back to Attitude or maybe even plan on switching back in 1 second the first time.

Mag alignment and GPS lag are the two things I have seen that make GPS modes oscillate when Attitude mode doesn't oscillate.  You could try changing the aux mag orientation angle numbers by say 5 degrees.  Try both adding and subtracting to see if either one helps.  I would try yaw, then pitch, then roll.

When flying in Manual mode when you give forward pitch only, does it tilt exactly forward or a little off to one side like it had a little roll too?  That would affect both Attitude and VR modes, but VR may just be closer to oscillation (toilet bowl).  Does it act the same in Attitude?

Good luck when you finally get to fly again.