Robust integral backstepping and terminal synergetic control of course keeping for ships

Course keeping control of ships deals with the automation of their trajectories for which a better rudder action is required to control the ship heading to continuously remain at the desired reference despite of environmental disturbances like sea winds and sea waves. For this purpose, this paper proposes Robust Integral Backstepping, Synergetic, and Terminal Synergetic controllers for good course keeping performance and reducing the energy consumption in course keeping control for ships. Output response of system, energy consumption and smooth-ness performances have been computed to check the efficiency of these proposed controllers. Lyapunov stability theory has been used for the proposed nonlinear controllers to ensure the global asymptotic stability of the system. Proposed controllers have been simulated on MATLAB/Simulink, where a comparative analysis of the proposed nonlinear controllers has been presented with each other, with conventional PID controller and with recently proposed nonlinear controllers for the course keeping control of ships.