High-order mismatched disturbance rejection control for small-scale unmanned helicopter via continuous nonsingular terminal sliding-mode approach

In this paper, the problem of finite-time control for small-scale unmanned helicopter system with high-order mismatched disturbance is investigated via continuous nonsingular terminal sliding-mode control approach. The key idea is to design a novel nonlinear dynamic sliding-mode surface based on finite-time disturbance observer. Then, the finite-time convergence and chattering attenuation capability is guaranteed by the continuous nonsingular terminal sliding-mode control law. Additionally, rigorous finite-time stability analysis for the closed-loop helicopter system is given by means of the Lyapunov theory. Finally, some simulation results demonstrate the effectiveness and predominant properties of the proposed control method for the small-scale unmanned helicopter even in the presence of high-order mismatched disturbance.