Severe problems with AC 4.0.3 - Drifting, FlowHold, logging,

ArduCopter Copter 4.0
21

I have taken another look at this and all I can come up with is the instability in flow hold may be because the altitude is deviating. This causes the gains on the flow hold to increase and that could be why you are seeing the instability. As this gets worse you then see the loiter start to drift.

If this is what is happening I can’t say why. Again this is one for Paul.

22

Can you tell me which flowhold device you have?
@Alberto_Ds which flowhold device do you have?

23

Hi Andy,

I have this:

24

So this uses the onboard gyros (CX-OF). The PX4Flow uses a separate gyro, I am wondering whether this is what @mtbsteve has.

Either way we are averaging gyro values over some time period in the driver which to me sounds like a very poor-man’s filter which we should actually replace with filtered gyro values. This would also mean adding a filter/notch filter to the PX4 driver, but that seems pretty doable.

@priseborough, @Leonardthall thoughts?

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Andy yes I am using a PX4FLOW sensor