Identification of longitudinal and transversal dynamics of a fast ferry

An analysis of the system identification methods have been carried out and a new alternative approach is proposed in order to estimate models for heave, pitch and roll dynamics of a high speed craft. As starting point, a first approach resolves the identification subject as an optimization problem to fit the best model, and uses genetic algorithms and nonlinear least squares with constraints methods applied in the frequency domain. The second and definitive one suggests a new parameterization which facilitates obtaining high quality starting values and avoids non-quadratic functions in the cost function. At last it is shown an example in which the two approximations are applied and compared.