Copter can not go straight in Loiter mode

ArduCopter
1

Hi, Thank you very much anyone could give me some help.
Now I have faced a problem that the vehicle can not go straight in loiter mode,. I have try many times to calibrate the magnetic and change GPS modules. it do not any changes. I have check my physical construction and motors, everything seems OK.

This is my testing logs: testing log

This is the tracking point.

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image.jpg1430×795 201 KB

This is the magnetic length paragraph.

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image.png1706×697 30.6 KB

2

Thanks, I have found that the magnetic is influenced by the motos, so I closed this issue.