Trajectory tracking optimal control with backstepping method for quadrotor helicopter

This paper propose a trajectory tracking control method for the quadrotor helicopter based on backstepping technique. To avoid the increasing complexity of analytically and improve the stability of controllers, the control system is divided into inner and outer loop, named attitude control and position control. The outer is designed as a full-driver controller and the inner is underactuated one. Although the underactuated system isn't commonly stable enough, the backstepping method used in this paper can solve this problem well. The outputs of position controller are regarded as novel inputs and sent to the inner control loop. The control inputs are obtained by the backstepping method. The stability of the control system is ensured by the Lyapunov stability theory. Finally, the effectiveness and stability of the controller is demonstrated through various track simulations.