Integral terminal sliding mode control for uncertain nonlinear systems

A novel methodology for designing nonsingular terminal sliding mode controller (TSMC) for a class of uncertain nonlinear systems is introduced. The system states can be guaranteed to reach a integral terminal sliding surface in finite time and then converge to the origin in finite time, while the singularity problem is eliminated. Compared with many existing works on nonsingular TSMC, the proposed method exhibits three attractive features: (1) the switching gain is only required to be designed greater than the bound of the disturbances; (2)when using boundary layer to alleviate chattering, for constant or eventually constant disturbances, zero steady-state error can be achieved; and (3) can be applied to higher order systems directly. Simulation results are presented to illustrate the effectiveness of the proposed method.