The Simplification of the MMG Model of Ship Motion With the Method for Parameter Calculation

As a simplified MMG (Manoeuvring Model Group) model, the ship motion model proposed in the standard of the International Electrotechnical Commission (IEC62065) has limitation of imprecise motion simulation for atypical ship, because of the simplification of some physical quantity such as propeller thrust and fluid resistance. To keep the concision of the IEC62065 model and address the issues of inaccuracy of atypical ship, this paper proposed a method of simplifying the complex MMG model with considerable accuracy for atypical ship into IEC62065 model. By designing motion simulation experiment of the complex MMG model for atypical ship, the relevant parameters in the IEC62065 model for the atypical ship will be calculated. Comparing the simulation results of the IEC62065 model with complex MMG model for the same atypical ship, it shows a high fitting degree between them. By using the method, a good model simplification effect can be obtained.