Direct self-repairing control for four-rotor helicopter attitude systems

In this paper, a tracking controller is designed based on direct self-repairing control for a fault four-rotor helicopter without any exact information on the fault, when the voltage of the actuator is damaged, so that this helicopter under fault conditions can perfectly track the reference model. A feedback compensator is designed to ensure the strictly positive real of such system. The stability of this reconfiguration system is proved by applying Lyapunov function. And the effectiveness of the proposed method is verified by simulation to ensure that the system performances under fault conditions can be quickly recovered to its normal level.