Zero-error tracking control of nonlinear systems with input saturation

This paper is concerned with the problem of tracking control for strict feedback nonlinear systems in the presence of input saturation. A transformation nonlinear function is employed to guarantee the saturation constraint. Then, to deal with the transformed system with nonaffine structure, an auxiliary integrator is introduced such that the use of backstepping is feasible in the control design. It is rigorously proven that the proposed control scheme can ensure that all closed loop signals are globally bounded, and the tracking error is asymptotically converge to zero. The effectiveness of the proposed approach is verified through a numerical example.