宇航产品振动试验用夹具绝对传递率的问题分析研究  

Analysis and research on absolute transmissibility of fixture for vibration test of aerospace products

作　　者：杨静静 孙杰明 马小明 YANG Jingjing;SUN Jieming;MA Xiaoming(Taist Laboratory of AVIC Fushida Technology Co.,Ltd.,Xi’an 710077,China;Xi’an Dongyi Comprehensive Technology Laboratory Co.,Ltd.,Xi’an 710065,China)

机构地区：[1]中航富士达科技股份有限公司泰斯特实验室,西安710077 [2]西安东仪综合技术实验室有限责任公司,西安710065

出　　处：《空间电子技术》2021年第4期95-99,共5页Space Electronic Technology

基　　金：国家自然科学基金(编号:51505331)。

摘　　要：振动试验作为考察产品可靠性的重要手段,如何正确有效的进行振动试验,是每个实验室或者试验人员必须要掌握的技能,振动试验夹具的优劣性,是保证振动试验顺利进行的重要前提,在实验室模拟振动时,输入量级和输出量级进行1∶1的传递,是不可能的。如果将振动台的激励源、夹具、产品看做三个不同的单元,则振动台的激励源可被视为输入,夹具视为传递,产品视为输出,这三者尽可能的刚性连接,由于阻尼的存在,在量级的传递过程中不可避免的会出现能量损失,导致无法实现1∶1的传递,但可将这种输入和输出之间的传递比尽可能的做到最大,也就是夹具的传递率最大,以这种假设为前提,以系统运动微分方程为理论基础,通过试验时的工作频率与产品及夹具在粘性阻尼系统中固有频率的关系,得出一个关于系统阻尼系数方程,同时借鉴半功率带宽法求的其阻尼系数,从而得到完整的输入与输出的关系比,即为夹具的绝对传递率,这样可以使得试验操作人员在进行试验的同时,更加明确输入的量级与产品实际经受的量级的对比关系,同时为工程中遇到此类问题时,提供一个切实可行的方法。Vibration test is an important means to investigate the reliability of products.How to carry out vibration test correctly and effectively is a skill that every laboratory or tester must master.The advantages and disadvantages of vibration test fixture is an important premise to ensure the smooth progress of vibration test.When simulating vibration in the laboratory,we hope that the input and output levels can be transferred 1∶1,but this is not the case impossible.If the excitation source,fixture and product of the shaking table are regarded as three different units,then the excitation source of the shaking table can be regarded as input,fixture as transmission,and product as output.The three are connected as rigid as possible.Due to the existence of damping,energy loss will inevitably occur in the transmission process of order of magnitude.We can't achieve 1∶1 transmission,but we can use this method The transfer ratio between input and output should be maximized as far as possible,that is,the transfer rate of fixture should be maximized.On the premise of this assumption,based on the differential equation of system motion,through the relationship between the working frequency of the test and the natural frequency of the product and fixture in the viscous damping system,the damping coefficient equation of the system is obtained,and the half power bandwidth method is used for reference In this way,the test operator can be more clear about the comparison between the magnitude of the input and the magnitude of the actual product,and provide a practical method for such problems in the engineering.

关 键 词：运动微分方程 半功率带宽法 谐振频率 对比关系 

分 类 号：TM501[电气工程—电器]