Help interpret flight record

[sar104]

OK - the only correlation appears to be the IMU/magnetic yaw discrepancy, which is a clear function of yaw. That means, I think, that there is a component of the magnetic field of the aircraft that is not being subtracted out by calibration, perhaps because it is too large, or that the compass is faulty. You could try demagnetizing next.

 

[BudWalker]

I'm not convinced. If you remove the t < 0 data then the 2π periodicity is still there in my opinion:

View attachment 76664

And the change in the yaw error before motor start is due to the aircraft being rotated:

View attachment 76665

Or viewed in yaw space:

View attachment 76667


The reason that it doesn't get corrected, I suspect, is that the change doesn't occur on takeoff - when I ran the tests it only reset on takeoff.

One more round. After removing the t < 0 data the data that causes the 2π periodicity occurs after the motors have stopped. It looks like the M2 was then picked up and moved about. @gershee were you wearing a watch. Or, otherwise move the M2 close to ferrous metal in the 4 secs after motor stop?

 

[sar104]

One more round. After removing the t < 0 data the data that causes the 2π periodicity occurs after the motors have stopped. It looks like the M2 was then picked up and moved about. @gershee were you wearing a watch. Or, otherwise move the M2 close to ferrous metal in the 4 secs after motor stop?
View attachment 77026

Good spot. Good tenacity too. Flight only:



Your hypothesis about handling it while wearing or carrying something magnetic is probably correct, although during the flight itself the measurements don't sample enough yaw space to be conclusive.

 

[raymo]

Well I dont power up the drone in the van preflight but there are times post flight I bring the drone into the van while it's still on, engines off though.

Looks like the equipment he added was a "van". Putting a small piece of metal on a Mavic can have bad effects and powering up over buried re-bar will have devastating effects on occasion. Enveloping a Mavic with a metal van can have nothing but bad effects. He added a van