Sliding mode control approach with nonlinear integrator
非线性积分滑模控制方法

A nonlinear integral sliding mode control approach is proposed for a class of uncertain nonlinear systems. To promote the performance of the traditional integral sliding mode control, this approach incorporates a new nonlinear saturation function which enhances small errors and will be saturated with large errors in shaping the tracking errors. While maintaining the tracking accuracy of the traditional integral sliding mode control, this approach provides better transient performances. Using Lyapunov stability theory and LaSalle invariance principle, we prove that the proposed approach ensures the zero steady-state error in the presence of a constant disturbance or an asymptotically constant disturbance. When the control input is constrained, the saturated controller operates like a PD controller with a nonlinear I term. Simulation example is given to demonstrate the effectiveness and robustness of the proposed approach.