Course Keeping Control for Ships Based on Bipolar Sigmoid Function Nonlinear Feedback

In order to make the ship course keeping algorithm more energy-efficient, this paper used the closed-loop gain shaping algorithm to design the linear controller, and then used a kind of bipolar sigmoid function nonlinear feedback to replace the original linear feedback. Theoretical analysis showed that in the same control effect, the proposed algorithm could reduce control energy. Took the ship Yukun to do computer simulation by using Simulink Toolbox of MATLAB, and the results indicated that the designed controller based on nonlinear feedback had good robustness. The average rudder angle was reduced by more than 10%. The proposed algorithm is concise and effective.