Altitude data fusion from other altitude sources

Development Team
1

I don’t know right now in Ardupilot what provision is there for fusion of altitude data from different altitude sources or if there’s any fusion of altitude data at all or just kind of switching system ?

When generally i use RTK GPS as primary altitude source, it seems like that EKF altitude estimation only use just GPS as altitude source, in cases like where my GPS switching from RTK float/fix status to less precise 3D fix status then altitude can vary a lot, and i don’t know what role actually EK3_ALT_M_NSE is playing in cases like as above mentioned, i thought this parameter will make baro play more role in cases like above, but in actual flights it doesn’t seems like that, can anyone please help in clearing the picture, what’s really going on where there are multiple altitude estimation sources available ?

Also how i can further minimise the role/weightage of RTK GPS altitude estimates if it not able to maintain RTK float/fix during the flight and make baro altitude estimations to take over the control of vehicle’s altitude ?

2

The latest github master improves a bit on the altitude department, but there is still to real fusion of multiple altitude sources, and no dynamic multi-source co-variance dependent weight adjustment.

So you can improve the code yourself by submitting a pull-request, because there are currently no magic parameters that you can change to achieve what you want.

3

Hello, which of the libraries of ardupilot that has the code for the altitude estimation/ efk estimation of altitude?

4

The normal EKF library: libraries/AP_NavEKF3