On-line of modeling ship manoeuvring motion by using least squares support vector machines

System identification combined with free-running model tests or full-scale trials is a kind of effective methods to determine the hydrodynamic derivatives in the mathematical models of ship manoeuvring motion. On-line support vector machines is proposed to identify ship manoeuvring motion model and ship motion first-order response model based on free-running model tests and full-scale trials, respectively. Established real-time online ship manoeuvring motion model can more accurately depict ship attitudes in time and have better robustness. The simulation results demonstrate the validity of the proposed identification algorithm.