H_∞ attitude control for helicopter based on slow switching principle

Novel control scheme for helicopter attitude control was proposed using the Two-Degree-Freedom(TDF) H∞method and slow switching logic.In this scheme,local robust controllers were designed using the TDF H∞method to establish the sub-controller group.Furthermore,the slow switching logic based on "dwelling time" was utilized to realize the stable switching between different controllers,and the helicopter attitude loop control could be achieved.Simulation results show the proposed scheme can exert the advantages of the TDF H∞method and reduce its design conservatity effectively.Good uncoupling performance and strong robustness against side wind disturbance are also demonstrated.