砂轮划片机模态测试中的传感器测点优化研究

针对砂轮划片机这类复杂设备振动模态测试中测试时间长、传感器数目难以确定和测点难以定位的问题,提出了结合有效独立法、QR分解法及模态验证准则、香农扩展定理对砂轮划片机主系统进行测点优化的方法。采用锤击模态测试方法对某一型号的砂轮划片机测点优化前后的模态进行了测试,识别出划片机主系统的振型和模态参数,比较测点优化前后的测试结果,表明测点优化的模态测试实现了将有限个传感器布置在关键的测点位置上并获取最接近真实信息的目的,缩短了测试时间,提高了测试精度,为复杂设备的振动模态测试提供了参考。

Optimal placement of sensors for modal testing of dicing saws

For problems of too long testing time,the difficulty to determine the number of sensors,and the difficulty to determine measurement points in vibration modal tests of a dicing saw,a method to combine the effective independent method,QR decomposition method,the mode assurance criterion (MAC) and Shannon expansion method was proposed to optimize measuring points for the main system of a dicing saw.The hammering modal test method was adopted to measure modes of a certain type of dicing saw before and after optimizing measurement points.Meanwhile,the vibration modes and modal parameters for the main system of the dicing saw were identified.The modal parameters before and after measuring points optimization were compared.The results showed that the modal tests after test points optimization can realize the target as close as possible to the real information using limited sensors arranged on key measure points,the test time is shortened,and the accuracy of tests is improved.The results provided a reference for the vibration modal testing of complex equipments.