Manoeuvring simulations on the design of three rudder-shaped like (RSL) bodies for low drag USV model

This paper presents an investigation into manoeuvring prediction simulation program to assess the effects of hydrodynamic derivatives for single and threerudder shaped like (RSL) hulls model. The study was conducted by simulating the manoeuvring mathematical model with values of hydrodynamic derivatives of a three-RSL hulls (model A) and comparing them with the values of hydrodynamic derivatives of single-RSL hull (model B) of a vessel during a turning circle test. Development of the manoeuvring time domain simulation programme by using MATLAB-Simulink software was included this study. The hydrodynamic derivatives and coefficients were obtained from a model test by performing various harmonic tests through a planar motion mechanism (PMM) at Universiti Teknologi Malaysia's Marine Technology Centre towing tank. By simulating the manoeuvring mathematical model and comparing with values of hydrodynamic derivatives, it was found that the tactical diameter and advance ability of the vessel during turning was not the same with Intemational Maritime Organisation (IMO) criteria. The simulation for turning circle trajectory model B was 0.65 times smaller than simulation model A in turning circle size. It showed that by using the values of hydrodynamic derivatives on a single-RSL and then combining their values into one unit to become three-RSL (model B), gave much smaller turning circle size trajectory as compared to the size of the model. Two types of three-RSL hull mathematical manoeuvring models were simulated and successfully demonstrated. In addition, these manoeuvring prediction simulations were proposed for use in the future study on manoeuvring characteristics simulation for three-RSL hull to comply with the IMO criteria.