Block Backstepping Trajectories Tracking Control for Unmanned Helicopters

This paper proposes a block backstepping trajectories tracking control scheme for a class of unmanned helicopters. The control objective is to make the position and yaw angle trajectories of the helicopter track the desired position and yaw angle trajectories. In order to design the controller, the helicopter system is divided into three subsystems at first. Then based on the block backstepping technique, four control inputs which constitute the helicopter controller are designed step by step in three subsystems. The asymptotic stability of the closed-loop helicopter trajectories tracking error system is verified based on Lyapunov stability analysis. Finally, numerical simulations demonstrate the effectiveness of the proposed block backstepping control scheme.