Research on Ship Path Following Control Method Based on MPC-IMFAC

Abstract：Objectives? This study aims to solve the problem of path-following control under environmental disturbances and model uncertainties especially the effect of external wind and wave environments on ship path-following control. Methods Based on the Model Predictive Control (MPC) controller, Improved Model-free Adaptive Control (IMFAC) is introduced as the path following control compensator. The error between the ship state and the predicted state is corrected to solve the problem of insufficient accuracy of the model under the environmental disturbance such as sudden cross wind and external wind waves, so as to improve the precision of path following control. Results Ship path-following control simulation experiments with a scaled-down KVLCC2 ship model. The results show that compared with the traditional MPC control, the MPC-IMFAC method makes the maximum absolute heading error of the ship decrease by 25.4% under sudden disturbances. The average absolute heading error decreases by 2.6% under time-varying environmental disturbances. Conclusions Through simulation verification, it is verified that this control method exists a better anti-interference ability while ensuring the path-following control accuracy.