Finite-Time Backstepping Sliding Mode Control Applied to the Yaw Control of UAV Helicopters with Actuator Faults

摘要

In this brief, finite-time backstepping sliding mode control technique is investigated to handle with the yaw control of non-affine nonlinear unmanned aerial vehicle (UAV) helicopters with actuator faults and unknown disturbances. Using a taylor series expansion technique, the control input in non-affine nonlinear system is presented as an explicit expression, which is convenient for controller design. Based on it, nonlinear disturbance observer is designed to estimate unknown compound disturbance. Furthermore, finite-time convergence backstepping sliding mode controller is designed to force tracking errors to small bounded sets in finite time, in which dynamic surface control avoids explosion of complexity and the sliding mode variable enhances system robustness. Then, the Lyapunov function is employed to verify the stability of the control system. Finally, the validity of proposed scheme adopted in yaw-channel dynamic model of UAV helicopters under actuator faults is demonstrated via simulation results.