时域响应中传感器附加质量影响消除

Elimination of transducer additional mass effects in time-domain responses

提出了一种时域内的传感器附加质量影响消除方法。利用时域实测自由响应数据,通过特征系统实现算法进行模态参数识别,获得传感器附加质量影响情况下的模态参数。以实测模态参数为基准,采用信赖域和非线性最小二乘算法对考虑传感器附加质量的结构初始有限元模型参数进行识别与修正,并以修正后的有限元模型为基础预测传感器附加质量消除所引起的模态参数改变。基于振型叠加法原理建立时域内传感器附加质量影响消除的识别方程组,并结合有限元预测的模态参数改变反演传感器附加质量影响消除情况下的时域响应。通过对一个实验室两端夹支梁模型实测时域响应中传感器附加质量影响消除进行研究,对所提出的方法进行验证。

A method was developed for eliminating transducer additional mass effects（ TAME） in time-domain responses here. By utilizing measured free vibration response data,modal parameters including the effects of transducer additional mass were firstly identified with the eigensystem realization algorithm. Then,the initial finite element model of the target structure with transducer additional mass effects was updated with the experimental modal parameters,and the changes of modal parameters due to elimination of transducer additional mass were predicted with the updated finite element model. Furthermore,a set of identification equations for eliminating TAME was set up based on the modal superposition method,and TAME were eliminated from the original measured time-domain responses with the previously predicted changes of modal parameters. Finally,the proposed method was verified with dynamic tests for a laboratory beam under clamped-clamped boundary conditions.