An Improved Real-Time LOS-Based Model Predictive Control for the Semi-Submersible Offshore Platform Under Ocean Disturbances

To enhance the autonomy of semi-submersibles, a Model Predictive Control (MPC) strategy was proposed based on real-time Line-of-Sight (LOS) to address the issue of thruster saturation. By identifying parameters using experimental data from sea trials, the dynamic model of the semi-submersible was derived and established. The kinematic and dynamic models were combined to construct a complete MPC prediction model, and the LOS method was integrated into the MPC strategy to achieve trajectory-tracking functionality. Unlike prior research that was validated exclusively through simulations, this paper further validated the efficacy of the improved LOS-MPC in real path tracking through a series of sea trials. The experimental findings indicate that the improved LOS-MPC approach is capable of rapidly guiding the semi-submersible to precisely follow the reference trajectory. In comparison to conventional PID controllers, the LOS-MPC-based path-tracking controller demonstrates enhanced effectiveness in terms of response speed, tracking accuracy, and robustness.