Low altitude flight using distance sensor data

PX4 Autopilot
1

Hi , I am encontering an issue: at low altitudes (<10m and lower speeds) only the down facing distance sensor should be used for alitude estimate. I see that distance_sensor/current_distance and vehicle_local_position/dist_bottom coincide, but that the local z position is quite wrong (it gives me negative values for a simmple hover flight). I am attaching an image that shown this and the link to flight review where you can see the local z pos: https://review.px4.io/plot_app?log=229cec44-3946-4bfd-885b-2fee28ecef45

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image933×1230 11 KB

Does anyone have any takes

Thanks,
~Nick

2

Hi Nick
Did you consider that PX4 uses NED frame, so the vehicle_local_position should have a negative z when flying up?

Cheers
Nick

3

I see, but how should that solve the problem? Or how would it give additional info to build upon?

~ Nick