Extracting Modal Parameters of Constrained Structure from Free Test Data
This study explores the method of extracting modal parameters of constrained structure from test data. The normal mode spectrum matrix constituted of low order frequencies of the structure can be derived from the free test data, while the normal mode shapes and the extra high order modes can be obtained through FEM analysis; The boundary constrains are equivalent as a kind of sub-structure, and the modal synthesis is used to extract the constrained modal parameters. Experiment and simulation are conducted and the results show that the extraction method based on the modal synthesis and which combines the experiment model and the analytical model is feasible.
B. Wu et al., "Extracting Modal Parameters of Constrained Structure from Free Test Data", Applied Mechanics and Materials, Vols. 110-116, pp. 4198-4203, 2012