Manual takeoff or at least set the altitude of takeoff

Hello,

I am trying to implement a manual takeoff with olympe sdk
I saw the userTakeOff that allows to arm the drone. However after that I try moveBy or PilotingCmd but nothing works.
Somebody has a solution, please?
At least, is there the possibility to change the altitude of takeoff that is 1meter by default?

Thank you for your help,
Best regards