Adaptive finite time smooth nonlinear sliding mode tracking control for surface vessels with uncertainties and disturbances

A study of the tracking control design for surface vessels is presented in this paper. A nonlinear adaptive approximation of the Super-Twisting algorithm (STW) is used to design a control law which provides desired stability properties even in the presence of unknown uncertainties and disturbances. By using this procedure, a desired trajectory is followed successfully and the tracking error is reduced to a small set containing the origin over the course of a finite period of time. An algorithmic solution was developed based on a small number of parameters with physical significance, which simplifies the process of determining the configuration. A numerical example is used to verify the effectiveness and robustness of the controller designed.