NED frame and Home Position

I have a question about Home Position and NED Frame.
I am working on offboard NED velocity guidance and I have noticed that, every time the drone takes off, the Home Position is updated to the current GPS position. On the contrary, it seems to me that the position that is used as reference for the NED frame is always the GPS position of the first GPS fix and it is never updated afterward.
This really messes with my algorithms because, if I restart the offboard program without having first turned off and on the UAV, I have no way to know the Geographic position of the NED reference point.

So, my question is:β€œIs there a way to update or just to get the NED reference GPS point used internally by PX4?”

Thank you so much

Hi @LorenzMeier,
is there a way to get (Latitude, Longitude, Altitude) of the point that is used as reference point for the autopilot NED frame? I mean the one that is initialized only once, at the first GPS fix?
I tried the reverse formula to compute this point from the current position (geodetic and local cartesian) but it adds an approximation error. It would be much easier to get it from the autopilot.

Thank you

I struggle with this problem since the beginning of using PX4.

the offboard control works in its local_frame. which is set on first gps fix. it would be sufficient when you get the cartesian coordinates referenced to the world-frame. then you could do a transformation between the coordinate frames. but this is also not working for me with MAVROS.

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