Oscillations due to IMU on GPS Pole?

Hi Guys

I’m using a Pixhawk 2.4.8 controller and a Here3 RTK Rover. I’m doing test flights in winds gusting to 50+ kph and its performance seems to be pretty good but it is getting oscillations which it pulls out of ok but it does nothing for my confidence.
I think the reason (apart from wind gusts) is that the Here3 Rover has an IMU in it that is mounted on a pole which must be wobbling +/- 10mm with that whipping. No doubt the error in the external IMU would cause some control issues. Has anyone else experienced this?

Is there any tips to design a good drone for harsh wind conditions?
I’ve attached a bin file which had these issues. Wind was 20-40kph at that time.
Time of the oscillations is most noteably 9min:2secs and 17min:25secs
Log file download: WeTransfer - Send Large Files & Share Photos Online - Up to 2GB Free

I’ve seen designs by others having a small support frame over the top.
Essentially like a miniature bar chair like design. In that way it’s firmly anchored at four corners and has little wind resistance whilst providing a firm base for a sensor like you’ve mentioned.

Something like this:


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The IMUs on the Here 3 are ignored. So you can ignore their vibration.

Just tune the copter properly without skipping ANY step, and you are golden.

Do not forget the notch filter too

Yea, that’s not an issue.

Set these as per the tuning guide based on MOT_THSDT_HOVER:
Configure the Dynamic Notch Filter. With that FC and ESC’s Throttle based. Continue tuning after these have been set and configured but that gumby frame will only get you so far.