Improved super-twisting sliding mode control for ship heading with sideslip angle compensation

This study aims to improve the performance of ship heading control and reduce the tracking error. A sideslip angle compensation method and an improved super-twisting sliding mode control algorithm are proposed. Firstly, a pre-filter is selected to reduce the effect of overshoot in turns. The time varying sideslip angle is estimated by an finite time extended state observer (FTESO), while external disturbance and internal uncertainty are also estimated, and the heading error is simultaneously amended by sideslip angle. To address the inherent chattering effect of sliding mode control, a reaching law based on improved super-twisting algorithm is designed. Additionally, a saturation compensation system is used to eliminate the input saturation characteristics. The stability of control system is proved using the Lyapunov theory. Finally, simulation results illustrate the effectiveness of the proposed controller.