Hover flight control of a small helicopter using robust backstepping and PID

In this paper, a robust control strategy applying on a small helicopter is proposed. The controller is designed using the backstepping approach based on Lyapunov function. In control design, a hierarchical inner-outer loop based structure is proposed to control the hover flight in the presence of external wind gusts. The outer loop (position control) employs robust backstepping controller to control the translational trajectory, while the inner loop (attitude control) controller is designed by means of PID controller that allow the stabilization of the attitude of a small helicopter. This new method combines the advantages of both robust backstepping and PID, particularly it is simple and easy to implement and tune in future real flight test. Finally, a computer simulation is conducted to show the hover flight control performance of the proposed controller in a gusty environment.