Drone undesired movements, need help to analyze LOG

Drone rotating at yaw and pulling to left side. Please help me to analyze the log and find the cause.


LOG file: https://drive.google.com/file/d/1b0X5gb54Jrks6kJhap6XkHu3voaC-Nnb/view?usp=sharing

Motor: Sunnysky X3520 720kv
Props: 14x7
ESC: Hobbywing Skywalker ESC 80A
PBD: Matek Xclass Pdb Fchub-12s
FC: Cube Orange with Arducopter 4.2.1
Frame: Quadrotor


You need to perform the basic tuning. All your PID gains seems default to me.

Your motor outputs are oscilating a lot, probably due to poor PID tuning.

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I didnt find the chance to do the auto tuning yet, tho i did use the initial parameters calculator and it was flying good with the exact same setup. I will do the Auto Tune at the first chance i can but i dont think this is the source of the problem.

Don’t underestimate the negative effects of poor tuning. Get the notch filter set up and follow the tuning instructions.

In the photo the motors don’t look level (maybe it’s just the photo). Make sure they are all level with each other and that the C of G is centered.

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In the photo motor arm lengths were not equal it was fixed before flight.

I ll set the notch filter but is it the source of unintended yaw movements? Cause i used exact same setup for 4 5 times.

I looked at a few other things:

The motors are fluctuating wildly. This will go back to the filters and the tuning. On several occasions motors would hit their minimum value.

The first compass (Mag0) is being severely affected by the power settings.

That yellow line in the graph should be flat. The second compass (mag1) isn’t having the same problem. You might want to clean up some of the wiring and see if that helps. You could try to set up COMPASS_MOT. Advanced Compass Setup — Copter documentation You may also need to disable the internal compass.

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