Estimating Input Forces of Plate Structures by an Inverse Method

Abstract

This study presents an inverse method to estimate the excitation forces from the dynamic responses of plate structures. The approach consists of two parts: the Kalman filter without input item and an estimator. The filter is used to generate the innovation sequence. The estimator then computes the onset time histories of the input forces by utilizing the residual innovation sequence through a least squares algorithm. The mathematical model of the plate structures was constructed by using the Finite Element Method. The practicability and accuracy of the proposed method were verified with numerical simulations from which the input forces of a rectangular plate were estimated from the output responses. In the numerical experiment, the plate was subjected to five types of input forces, i.e., sinusoidal, triangular impulse, rectangular impulse, a series of impulses and random. The simulation results indicate that the proposed method has a good tracking ability for identifying the input forces of plate structural systems from the noisy dynamic responses.