Abstract: A new control scheme for helicopter hover is developed. The scheme does not change the original structures of the velocity loop, adding only a robust controller as an outer loop for the original velocity loop. For this reason, the new scheme improves the robust properties of the variation of the parameters in the helicopter hover. The design method of the robust controller combined with the controller of the helicopter hover is given in detail, and the computer simulation results well explain the function of the robust controller in the example.

Key words: robust controller, servo-compensator, stabilizing compensat or helicopt er hover