振动环境试验中的结构模态参数识别  

Modal parameter identification based on vibration test

作　　者：周天朋[1] 夏江宁[1] 毕京丹[1] 

机构地区：[1]北京强度环境研究所,北京100076

出　　处：《强度与环境》2008年第6期25-29,共5页Structure & Environment Engineering

摘　　要：振动环境试验中的测点加速度响应与台面加速度响应数据之比,可以被看作结构频响函数的加权和。因此,可以将加速度传递率作为被测结构的一个"广义频率响应函数"来提取结构的模态参数,如固有频率、阻尼比。求解广义频响函数时,根据加权最小二乘法构造目标函数,并通过遗传算法迭代,得到结构的固有频率、阻尼比。应用此方法对某卫星的振动试验数据进行模态分析,得到的结果与模态试验结果一致。The acceleration＇s ratio at measuring point to that on the base is equal to the sum of the structural weighted frequency response function. So, the acceleration transfer mobility is a ＂generalized frequency response function＂. Modal parameters, such as nature frequency, damp ratio could be obtained from the acceleration transfer mobility. Target function is constructed according with weighted least-squares algorithm to solve generalized frequency response function. Genetic algorithm is used to obtain least value of target function, at the same time, receive structural nature frequency and damp ratio. The method is used to identify modal parameters of a satellite. Comparing the modal test, the results are fairly well.

关 键 词：振动试验 模态识别 加权最小二乘法 遗传算法 

分 类 号：V216.2[航空宇航科学与技术—航空宇航推进理论与工程] O321[理学—一般力学与力学基础]