In this paper, parameter identification is carried out for the coefficient matrices in the equation of motions of offshore structures subjected to wind generated wave forces. The extended Kalman filtering technique is employed to estimate the parameters in the nonlinear equations related to the nonlinear hydrodynamic forces.
For stable and convergent estimation, the exponential data weighting and the weighted global iteration procedures are incorporated into the extended Kalman filter.
The results of the simulation study on simplified cases indicate that the exponential data weighting scheme is more effective than the weighted global iteration technique. The former is found to be less sensitive to the inaccuracy of the initial guesses for the unknown parameters and the observational noise intensity and less time consuming to estimate parameters.
