ZG Control for Ship Course Tracking with Singularity Considered and Solved

Zhang dynamics (ZD) and gradient dynamics (GD) are both effective methods for online problems solving. By combining ZD and GD methods, an innovative ZG (Zhang-gradient) control method is thus proposed and investigated in this paper, which is applied to ship course tracking for the first time. Firstly, for a constant parameter setting, we design a ZD-based controller to solve the tracking-control problem of a ship course system with no singularity appearing. Then, for a time-varying parameter setting, the ZG method is applied generally to solve the singularity-containing tracking-control problem of such a system. Simulation results further demonstrate and verify the feasibility and superiority of the unified ZG method in fulfilling the tracking-control task while conquering the singularity problem for the ship course system.