Identifying physical parameters of structural dynamical system using Padé approximation

A new identification method for the physical parameters of structural dynamical system is proposed. The Padé approximants is used to fit the dynamic stiffness curve of the structural dynamical system, and the coefficient matrices in the Padé polynomial are determined by the least squares method. In addition, genetic algorithms is adopted to optimize the parameters in Padé polynomial. Then the mass, damping and stiffness matrices in the physical space can be extracted from the Padé polynomial. Numerical examples illustrate that the proposed method has good accuracy and is effective for viscous or non-viscous damped systems.