考虑测量误差影响的改进随机激励辨识方法  

An Improved Random Excitation Identification Method Considering the Influence of Measurement Errors

作　　者：盖晓男 于开平[1] GAI Xiaonan;YU Kaiping(School of Astronautics,Harbin Institute of Technology Harbin,150001,China)

机构地区：[1]哈尔滨工业大学航天学院,哈尔滨150001

出　　处：《振动．测试与诊断》2020年第6期1105-1111,1231,共8页Journal of Vibration,Measurement & Diagnosis

基　　金：国家自然科学基金资助项目(11372084)。

摘　　要：为研究考虑测量误差影响的随机激励辨识方法,首先,在逆虚拟激励法中引入模型测量误差和响应测量误差,推演总结影响随机激励辨识精度的因素;其次,分析提高辨识精度的途径;最后,引入系数矩阵来减弱频率响应函数矩阵的条件数对随机激励辨识精度的影响。以悬臂梁结构为对象进行多点随机激励辨识的数值仿真研究;以复合板结构为对象,进行多点随机振动试验研究。结果表明,与传统的逆虚拟激励法相比,此改进方法在考虑测量误差的同时能有效地提高某些固有频率附近的识别精度。In order to discuss random excitation identification method considering the influence of measurement errors,model measurement error and response measurement error are introduced to inverse pseudo excitation method.Influencing factors of random excitation identification accuracy are deduced.The ways to improve identification accuracy are analyzed.Coefficient matrix is introduced to reduce the effect of frequency response function matrix′s condition number on identification accuracy.Numerical simulation of multi-point random excitation identification of cantilever beam is carried out.Taking a composite plate structure,multi-point random vibration tests are conducted.Results show that,compared with traditional inverse pseudo excitation method,the proposed method can effectively improve random excitation identification accuracy near some natural frequencies with consideration of both model measurement error and response measurement error.

关 键 词：随机振动 激励辨识 测量误差 系数矩阵 

分 类 号：TH113.1[机械工程—机械设计及理论] O324[理学—一般力学与力学基础]