[DAS]

Hi.

I have a problem with small quick oscillations in flightmode attitude with GPS-assist.

I have recently upgraded my Revo from v.15_02_02 to v.16_09 and now i have problems with small quick oscillations.
I am using FM rate, attitude, attitude + GPS-assist.
When I am in rate or attitude mode everything looks fine and it flies ok except for a slight drift towards SE motor in hover but no noticeable oscillations.
When i go in to attitude + GPS it starts to oscillate.
I did not have this issue with the previous firmware. Before the upgrade the quad flew very well and GPS assist was spot on.

It is a zmr250 with OP Revolution and OP GPS and i use aux mag only and ins13.
accel filter set to 0.07

I have looked through the GCS set a couple of times but I can not find anything obvious and I have set home pos, and completed all mag, gyro, accel, temp calibration steps with oplink and with the quad setup in the way it is supposed to be when I fly it.

I would appreciate ideas what to look for.

BR
Daniel Stromberg

[TheOtherCliff]

Does this happen only when pointing in a particular compass direction?  There is an old issue about that, but it even affected 15.09.

Did you recalibrate your ESCs?

Do your output bank update rates match what you had in 15.09?

Did you copy your stab bank PIDs, VtolPathFollowerSettings, TPS curve, output settings, Gyro Tau, etc. from 15.09 or are you using defaults?

I know of at least one thing that could cause it and there may be others.
System -> Settings -> StabilizationSettings -> MeasureBasedDTerm
was added.  Set it false to act like it used to, but I wouldn't guess that it is the cause.

[DAS]

Yes it happens in all directions. But I never had this problem with the old firmware wich was the last of the OP ones.

With the update I did an update and erase, and then I walked thru the set up wizard.
ESCs recalibrated.

update rate match.  I am still using a couple of old turnigy plush 12a esc and they were set to Rapid ESC and 400Hz.

I did not copy stab bank PIDs, I tuned them manually.

regarding VtolPathFollowersettings, TPS curve, Gyro Tau. I have been using the default ones. Not using TPS.


But today I really bad idea, weather was exellent so I thought today is the perfect day to adjust and try things.
and for some dumb reason I set esc to standard ESC with 50Hz (because I know the ESCs are old) but I did not set Stab PIDs to default. Took of in Rate mode and... Well result was quite wiggly with an assplant and a broken GPS anntenna mounting post.

After that I did a quick set up without the GPS with 50Hz ESC update rate and defalut stab PIDs. Rate mode was like almost ok but with oscillations in climb and decent. and when i flipped over to attitude it was small oscillations like the ones I had with Attitude + GPSassist.
But as I don't want to have it without GPS i did not continue today, tomorrow I will fix the GPS mounting post and hopefully if we get the same good weather i will do a completely new setup again.

The hardware I am using is:
ZMR250 frame
sunnysky 2204 2300kv
turnigy plush 12a ESC (standard firmware)
Spektrum radio DSM2 connected to FC with PWM
OpenPilot Revolution FlightController
OpenPilot GPS

//
Daniel Stromberg
 

[TheOtherCliff]

Well, given a different set of PIDs and 50Hz ESC update rates, I can't really say that is should fly the same as before. 

[DAS]

Yes I can confirm that it was a bad idea so if anyone else is planning to do the same, please don't. You will end up reparing.

Well got my quad back to one piece today, did an upgrade and erase to v16.09, recalibrated ESCs and all the other sensors.
Now I am using PWMsync for my ESCs. Tried on Rate mode with default PIDs and it was ok I raised the PIDs alittle no oscillations allmost no drift. Flipped over to Attitude mode also looking good and with no drift, raised kp alittle ki set to 0.
In climbouts I have no oscillations in decent there is small wobble tried to work with raising the left side of the TPS curve but I am not sure that it got any better it was not worse anyway.
So far the quad flies as good as in the v15.02.02 firmware. But when i kick in the Attitude + GPSassist i get some small oscillations, way better than before but there is still some to get rid of to get it perfect.

And now to the hijacking of my own thread.
Right now i am using a Spektrum DX7 dsm2 and the FC is wired to my radiorx with PWM one wire to each channel. Let's say that I want to upgrade my ESCs to some that can handle Oneshot, oneshot125, multishot etc do I need to change my reciever aswell to one that can handle PPM. I think I have seen something about this but I can't remember if it was just with the OP CC3D FC or if it was with all FC boards.

Anyway it felt good to get the quad flying again and that it was even better than before.

//
Daniel Stromberg

[TheOtherCliff]

From what I recall, there is an issue such that using OneShot on a CC3D required you to use PPM on a different pin.  It is a CC3D issue only and based on the fact that CC3D MCU just doesn't have as many pins as Revo class FC's.