I’m following the Arducopter webpages on tuning. I set my parameters to those recommended by the Mission Planner wizard and did a couple of flights.
The first flight was just in STABLIZE mode while the second flight was STABILIZE for takeoff, followed shortly by ALTHOLD for most of the rest of the flight.
These are the logs (download them first by clicking on the Download icon otherwise it won’t work → password is my username):
You can see the yaw is okay, but DesRoll/Roll shows lots of noise. In practical terms, the drone was jerking around a bit, like a hyperactive child.
How would I reduce this behaviour? The documentation only talks of problems with oscillation which I do not appear to have. The problem I have is random twitches.
Because it wants to be tuned ASAP
To many overshoots on both pitch and roll axes (±5 degrees).
You can do some really short flights for manual tuning in alt hold and reduce the P values with some small steps until you see a little bit fewer overshoots.
If your vehicle is symmetrical, do both roll and pitch at the same time.
If you are confident enough about your vehicle (could be some overshoots but no undesired, unstable movements that may lead a crash), you can start the AutoTune process.
Basically, is Autotune what I should be aiming to do? The docs suggest doing all sorts of things but it seems that the Autotune sort of is the final word in tuning.
Thanks for the link - the video was useful. Before using the Mission Planner tuning initial params tool, I was “okay” with the quadcopter performance. I might as well go back to the original params because the drone was more controllable than it is now with the Mission Planner-suggested params.
Then I suppose I should do an Autotune?
Do some roll and pitch in ALTHOLD and LOITER modes. Start from some low stick movements to quick and high stick movements (somewhere 30 degrees). You shouldn’t see any instabilities. When you see instability, change PID values (for example, lower P). I highly suggest you follow the wiki. Yes, AutoTune is the last part. You can also divide the autotune process into some parts from weak aggressiveness to high.
I’ve read the wiki several times and am attempting to follow it but it says nothing about what to do if your drone twitches about randomly.
I’ll just assume that the correct thing to do in response to this is the same as the response to having an unstable (i.e. oscillating) drone.
I don’t know how you ended up these:
I would reset the PID’s to default. Run the Initial Tuning setup. Configure the Dynamic Notch filter, then run Auto Tune.
How do I reset PID values to defaults?
The format of the parameter file from QGC is not very user friendly. Best to export it from Mission Planner or use Mission Planner to extract it from a .bin file.