Identification of Modal Parameters for Defective Vibration Systems
نویسندگان
چکیده
A defective vibration system is a special linear vibration system which can not be completely uncoupled by linear transformation. Previous studies have shown that the modal models of defcctiw vibration systems are determined by modal parameters (modal frequencies, damping ratios and mode shape vectors), as well as the structural matrices of the vibration systems. So the whole identification of defective vibration systems includes two steps: (1) identification of the structure matrices; (2) estimation of the modal paraneters. In this paper, the theory about the modal paraneter identification of defective vibration systems by using the free responses of the systems is presented. The theory supposes the structure matrices of the systems are known, and uses the non-linear least square method for estimations of the modal parameters. Identification examples ax aJso presented.
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