heubie

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I know this looks like a stupid question and it probably is but this is the thing.

I build my first drone and running on a revo with aux mag and after 3 weeks or fiddling I finally got it to fly under gps in velocityroam.  This looks like the safes point to start. But the controls are far from tuned (lots of overshoot and the drone goes down under forward travel).

I did my share of reading but most of the stories are from small race drones. Mine is a large heavy H.A.L. 585 which I want to use to shoot stable videos. I did find some knobs in GCS to play with but the "basic" PID values I did not find. Can somebody point me in the right direction and tell me where to start from. 

I'm am running the NEXT version on a revo, 30A ESC with simonk on it and 935KV Multi Star Motors with Propellers 10 x 4.5 powered by a 3s LiPo 5000.

System -> Settings -> VTOLPathFollowerSettings has all the PIDs and setting to make this smoother for a particular aircraft.  Knowledge and Experimentation are the keys.  Wikipedia has a good article on PIDs.  Beware that you are stepping into college course level stuff.

For best video you must be aware that the GPS signal is not smooth.  Watch how far and fast the GPS moves around with the quad on the ground.  That is how much it will move, just because the GPS is drifting around.  You can even see the PFD (Artificial Horizon) move around a little when the quad is on the ground.

Currently the best solution is to avoid using GPS when shooting video that you want to be really smooth.  You can set it up to be rock solid smooth if you don't use GPS.  There may be an option in the next release that gives smoother PFD with minimal sacrifice.

One GPS solution that is smoother is to use a real (not clone) DJI GPS with the latest (unreleased) code.  They cost about $43 (shipped) on eBay.  This GPS is configured for smooth, not for quick motions.  Along the same line, for UBX based GPS you can change GPSSettings.UbxDynamicModel to something slower than Airborne 1G.  I think that is the difference in the DJI GPS.
« Last Edit: September 24, 2016, 09:00:43 pm by TheOtherCliff »

heubie

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thx for the reply. I will do some stationairy testing when I back home. I looked at the info on OPtune and give that a try to.

heubie

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After updating the firmwar(16 rc) and rerouting some cables it looks like de aux mag is stable. When look at al the values stationairy everything looks ok.
Flying in velocityroam (am still a beginner) is getting better. But still the behaviour is not optimal.
I setup the txpid tune. Put min to .0015 and max to .00750 and the pid values change when i turn the aux knob.

But when I put in the air and turn the knob I can get it to oscillate......
First I did it in VelocityRoam but then I read somewhere that tuning is not possible in that mode.
Then I tried stabelize1 Using stab for pitch and roll but no success ether.

Finally it tried  Stabelize3 using rate for pitch and roll but since I only have like 1 real flight hours there is now way I can keep the drone in the air and turn the knob at the same time.

Is there a way to tune in flight with some flight-aid for a beginner?

16.09 RC1 has AutoTune.  You might give that a try.  AutoTune tunes the non-GPS modes (which are automatically used by the GPS modes too).

Read at least the important part of the AutoTune wiki for that.

The simple version is:
- use stock PIDs (or known, slow, smooth PIDs) in bank #1
- set up FMS (flight mode switch) for
--- FMS#1 Attitude mode manual throttle (Stabilized 1) on bank 1
--- FMS#2 AutoTune mode on bank 1
--- FMS#3 Attitude mode manual throttle (Stabilized 1) on bank 3
- take off with FMS #1
- switch to FMS #2 and after 2 seconds, it will shake around for 60 seconds
- land after shaking stops
- disarm
- switch to FMS #3
- arm
- carefully take off to test the new PIDs (be ready to instantly drop by using zero throttle if anything strange happens)

If everything works, set up FMS as you like, with all modes pointing to bank 3
« Last Edit: September 24, 2016, 09:40:03 pm by TheOtherCliff »