A unified ship manoeuvring model with a nonlinear model predictive controller for path following in regular waves

• Published in: Ocean engineering 2022-01, Vol.243, p.110165, Article 110165
• Main Authors: Sandeepkumar, R., Rajendran, Suresh, Mohan, Ranjith, Pascoal, Antonio
• Format: Article
• Language: English
• Subjects: KVLCC2; LOS; Model predictive control; Nonlinear MPC; Path following; PID; Regular waves; Unified seakeeping and manoeuvring model
• ISSN: 0029-8018; 1873-5258
• DOI: 10.1016/j.oceaneng.2021.110165

In this paper, a nonlinear model predictive controller for path following of a surface vessel in the presence of regular waves is studied. A model predictive controller is developed for a 3DoF unified manoeuvring model of the KVLCC2 crude oil tanker. The surge, sway and yaw motions of the ship are influenced by the second order wave drift forces and moments calculated based on a potential flow solver. Propeller thrust, rudder and hydrodynamic forces and moments are computed using empirical formulas available in the literature. For path following purposes, waypoints are assigned in head and beam wave conditions and a line of sight algorithm computes the reference heading angle. The rudder control is exerted by a nonlinear model predictive controller and the effectiveness of the controller is studied. The performance of the nonlinear model predictive controller is compared against that of a basic PID controller. •A nonlinear model predictive controller (NMPC) is developed for a unified manoeuvring model.•A 3DoF surge–sway–yaw MMG model is used to represent ship dynamics of a KVLCC2 tanker.•The wave drift forces are calculated based on Salvensen method.•The path is defined using waypoints and a Line of Sight (LoS) algorithm is used for guidance.•A nonlinear model predictive controller (NMPC) which facilitates nonlinear optimization is used for feedback control.