Obtaining the Surge Hydrodynamic Derivatives of a Container Ship

Abstract

Ship maneuver simulators and autonomous vessels rely substantially on the hydrodynamic coefficients identification to accurately reproduce its dynamics. Therefore, the objective of this article is to propose and execute a specific maneuver to identify the surge hydrodynamic derivatives for a container ship class. For this purpose, ship motions are generated through a maneuvering model implemented by Fossen (1994) in Matlab. Therefore, given the container ship and its sea trial data, a system identification method for nonlinear dynamics (SINDYc), adapted to identify hydrodynamic derivatives directly, and a regression method (LASSO) are applied to obtain the hydrodynamic coefficients that satisfy the tested maneuver. The maneuver is repeated with the new coefficients and the trajectories are compared. The results obtained for the ship’s coefficients and trajectory show good adherence, specially for the most excited terms.