IDENTIFICATION OF TIME-VARYING MODAL PARAMETERS USING LINEAR TIME-FREQUENCY REPRESENTATION

作     者：XuXiuzhong ZhangZhiyi HuaHongxing ChenZhaoneng 

作者机构：DepartmentofMechanicalEngineenngShanghaiMantimeUniversityShanghai200135China NationalKeyLaboratoryofVibrationShock＆NoiseShanghaiJiaoton9UniversityShanghai200030China SchoolofMechanicalEngineeringShanghaiJiaotongUniversityShanghai200030China 

出 版 物：《Chinese Journal of Mechanical Engineering》 (中国机械工程学报（英文版）)

年 卷 期：2003年第16卷第4期

页      面：445-448页

核心收录：

学科分类：08[工学] 080203[工学-机械设计及理论] 0802[工学-机械工程] 

基　　金：Automobile Industrial Science Foundation of Shanghai (No.2000187) 

主　　题：Linear time-varying system Modal parameter identification Hilberttransform Gabor expansion 

摘      要：A new method of parameter identification based on linear time-frequencyrepresentation and Hubert transform is proposed to identity modal parameters of linear time-varyingsystems from measured vibration responses. Using Gabor expansion and synthesis theory, measuredresponses are represented in the time-frequency domain and modal components are reconstructed bytime-frequency filtering. The Hilbert transform is applied to obtain time histories of the amplitudeand phase angle of each modal component, from which time-varying frequencies and damping ratios areidentified. The proposed method has been demonstrated with a numerical example in which a lineartime-varying system of two degrees of freedom is used to validate the identification scheme based ontime-frequency representation. Simulation results have indicated that time-frequency representationpresents an effective tool for modal parameter identification of time-varying systems.