loiter problem

[hani]

Hi everyone,
I have a problem with my copter in loiter mode. I cant find the sweet spot (throttle input) where the copter hovers at a fix altitude. It tends to go either up or down on its self. Could you please give me any sugestions?

[coppelia]

Hello,

normally you would continually adjust the thrust based on the height. So what exactly is the problem? Writing the controller, or finding out about the robot's altitude?

Cheers