Nonlinear system parameters inversion method based on substructure

The nonlinear system parameter identification problem with incomplete input and output information is studied. The consideration of Rayleigh-type proportional damping introduces a nonlinear system parameters identification problem. In this paper, combined with decomposition algorithm, the proposed method obtains minimal norm least square solution of the unknown system parameter and the unknown input in one step by using Moore-Penrose Pseudo-inverse, The substructure method offers an efficient approach for the dynamic detection of engineering structures with limited observations. Compared with Compensation Method, the method is more efficient and has a wider application background. The numerical example shows that the proposed approach can effectively identify the structural parameters from incomplete measurements. The algorithm is expected to provide an economical, simple, efficient, and robust system identification technique that can be used as a nondestructive defect detection procedure in the future.