MIMO模態測試於精密CNC平面磨床之應用

Application of MIMO Modal Testing to a CNC Surface Grinding Machine

王鴻智(Hung-Chih Wang) ； 李明儒(Ming-Ru Lee) ； 曹書銘(Shu-Ming Tsao) ； 廖明亮(Ming-Liang Liao)

《中華民國振動與噪音工程學會論文集》 1995 (1995/06) Pp. 137-148

https://doi.org/10.30028/CSSVANNUAL.199506.0137

摘要

本文是利用MIMO FRF (Multiple Input Multiple Output Frequency Response Function)之方法進行某型CNC精密平面磨床模態測試(Modal Testing)。此測試利用兩個激振器激振，共189個加速度頻道，在400Hz之內嵌合出19個振型，並用頻率響應函數合成法驗證，結果甚佳，顯示這些振型在這頻率範圍內，足以代表結構之整體動態特性。文中將介紹MIMO FRF之原理、試驗設備、試驗步驟及結果。此測試求取之結構動態特性可爲偵錯時之資料庫，並可驗證有限元素分析(FEA)之準確性。特別值得一提的是用有限元素分析時可以利用這些振型及振頻，來模擬磨床組件間及地板之動態參數，在缺乏結合點動態特性之情形下，此不失爲一好方法。

並列摘要

In this paper, the MIMO FRF (Multiple Input Multiple Output Frequency Response Function) estimation method is applied to a CNC surface grinding machine. The measurement system included two exciters and 189 acceleration channels. Nineteen mode shapes are obtained in the frequency range of 400 Hz. The synthesized FRFs using these modes agree with the test results quite well. The results obtained from modal testing can be used to validate those of FEM and can be used as a data base for troubleshooting. Furthermore, the dynamic stiffness of the interfaces of the grinding machine can be estimated from these results. In the absence of joints properties, this is a good alternative method.