Attitude control of a small-scale helicopter based on backstepping

In this paper, the attitude control of a small-scale helicopter is investigated. The main rotor flapping dynamics is explicitly explored to improve the control performance. Backstepping technique is adopted to derive the control law, and extended state observer is applied to estimate the immeasurable states and disturbance. Together with these two approaches, sliding mode controller is designed to force the actual attitude of the closed-loop system to converge to the reference attitude. Simulation and experimental results show that the proposed controller yields excellent performance and robustness.