(SOLVED)Strong oscillation not getting better with extensive PID Tuning

ArduCopter Copter 4.0
1

Hello everyone!
I am relatively new to the community, so please forgive me for “dumb” questions.
I am building a quadcopter with Ardupilot OS.

The hardware is as follows:
Motors: 4x MultiStar Elite 2810-750kv
ESC: Holybro Tekko 32 30amp
FC: Matek F405-CTR
Props: 10x4.5
RX: FrSky R-XSR
TX: FrSky Qx7
Battery: Turnigy 25-35C 5000mAh 4S
GPS: Matek SAM-M8Q(without magnetometer)

I am facing a very strange problem with oscillation. The quad is oscillating heavily no matter what I set the PIDs to. Has anyone an idea what may cause these kind of oscillations?

MissionPlanner says that the compass is not healthy(the onboard one of the FC), but imho this should not change oscillation.

If anybody has any tips regarding this topic, please consider helping me out here.

Best regards
Jonathan

UPDATE: (SOLVED)
The problem was entirely not related to any PID values.
The problem was pretty simple. It was caused by wrong Motor connection. Apparently ABCD does not stand for 1234 and the signal connections on the FC are not numbered chronological with 1234 but with 1243. So the FC could never send the right correction signals to the right motors causing severe oscillation.
I BEG YOU TO MAKE THIS (ABCD does not mean Motor 1234) WAY MORE CLEAR IN THE DOCUMENTATION AND THE MISSION PLANNER MOTOR TEST FEATURE. THIS IS NOT OBVIOUS FOR BEGINNERS! TALK ABOUT THIS AT THE START OF “INITIAL SETUP”
We changed the mapping for the motors in the Mission Planner and know everything works fine.

2

Have you checked the parameters from this link: Tuning Process

3

I have indeed not. A beginner mistake I guess. I´ll try it out immediately and let you know if it worked.
Thanks Igor

4

Once you’ve gone through the tuning process and an auto tune, be sure to post log files if you need assistance.

5

The problem is AutoTune is impossible to do, as they quadcopter is so instable it can´t even launch and get into Auto Tune.
UPDATE:
Tuning the listed parameters that Igor/ajghor talked about I didnt get any improvements at all. I don´t really know what to do now. I´ve tried all kinds of PID Values with little to no improvement at all.
I really don´t want to blame it on hardware as I am a beginner and have probably just not done something that is required for a project like mine to work, but could a broken/bad magnetometer cause such behavior?
Any tips or advice would be immensely appreciated.

6

Post your parameters and a log of the problem

7

UPDATE: (SOLVED)
The problem was entirely not related to any PID values.
The problem was pretty simple. It was caused by wrong Motor connection. Apparently ABCD does not stand for 1234 and the signal connections on the FC are not numbered chronological with 1234 but with 1243. So the FC could never send the right correction signals to the right motors causing severe oscillation.
I BEG YOU TO MAKE THIS (ABCD does not mean Motor 1234) WAY MORE CLEAR IN THE DOCUMENTATION AND THE MISSION PLANNER MOTOR TEST FEATURE. THIS IS NOT OBVIOUS FOR BEGINNERS! TALK ABOUT THIS AT THE START OF “INITIAL SETUP”
We changed the mapping for the motors in the Mission Planner and know everything works fine.

1 Like
8

The Motor Test order is done in Mission Planner for a purpose. So all craft regardless of configuration test in the same order. The note on the Motor Test screen indicates the order. Further, the link in the screen to the Wiki page for this explains the test order with big bold red letters.

1 Like
9

I made the same mistake on my very first arducopter. ABCD not equaling 1234 isn’t terribly intuitive. That said, it’s why doing a motor test is so critical for motor layout and motor direction.