Does ground effect compensation works well in Copter 4.0.7?


I have problem on auto landing, there is a small bouncing just before touchdown sometimes.
Now I’m focusing on the ground effect compensation and gathering some information.
I also read a topic GND_EFFECT_COMP not working as good as in Copter-4.0.

Unfortunately, I’m using modified version of ArduCopter based on 4.0.7 (22/Feb/2021) and I cannot upgrade the version to 4.1.0 immediately.

I tested with additional engage flag for ground effect compensator in the “AP_NavEKF2_PosVelFusion.cpp”.
I found that the compensator turns on when a decent starting with Land/RTL mode by " getTouchdownExpected()", and after “Land complete EV” occurred by getTakeoffExpected().

Is the compensator works propely?
If not, would you please tell me what is the reason and solution of the bug?

Thanks and Have a nice day.

There was a bug that I know affected quadplane, maybe also copter. I think the fix will be in 4.1

Not sure about backporting…

Thank yo Soooooooooo much.
Still I need to test my code,
but I found the difference between my version and master version.
In the master version, the ground effect compensation keep working during landing sequence (under 10m, -0.5m/s climb rate)
But, mine is not.
The compensation just turns on when landing sequence is started for 1 second.

Have a nice day.