Further considerations on mathematical manoeuvring models

For the prediction of the ship's manoeuvrability use is made of computer simulations based on mathematical models. Empirical methods exist for the determination of the hydrodynamic characteristics in these models. Up till now, the derivation of the non-linear hydrodynamic coefficients by means of these empirical methods is not very accurate. However, these non-linear coefficients influence the ship's manoeuvrability significantly. For this reason further research is performed on the assessment of the non linear terms. Some results of such studies are presented in this paper.