Drone with undesired circular movement after a normal flight

Hello,

I was flying a hexarotor normally, without any issues. After landing and then starting a new flight a few minutes later, it exhibited an undesired behavior: without moving any control stick, it began to have a circular movement that increased the radius over time.

In this log, you can observe it:
https://review.px4.io/plot_app?log=f3efc137-95c3-4fe4-9a94-244de8bd4163

Logs of the flight minutes before the undesired behavior:
https://review.px4.io/plot_app?log=d2cd93ba-306b-45a3-b87e-b0695e0751dd
https://review.px4.io/plot_app?log=ce8a0ef7-ffde-42b3-a8e5-a365442a16b2

What’s strange to me is that when it exhibited this undesired behavior, I would land the drone and try to take off again, but it didn’t help. However, the next day, without changing any parameters, it flew normally, without any issues. Then, it would go back to having the problem, and if I waited for some time, it would operate normally again.

Does anyone have any advice on what could be happening? Thanks.

This phenomenon is generally caused by geomagnetic interference.

Hi,
i think your offboard companion computer has a communication issue. Check the serial cabling for any cuts

Search for the term “toilet bowling”.

Make sure you use a GPS with mag and mount it far away from power electronics.

And redo the mag calibration.

Also see: