The modal testing experiment presented here is performed by one branch of SIEMENS Medical using ModalVIEW software and National Instruments DSA hardware as the modal testing and analysis tool. The analysis result provides instructive guidance on the design of their products.
The testing object is a steel frame for magnet coil. There are some challenges to perform modal testing of the structure:
In this modal testing experiment, the following software and hardware are used：
4．Tri-axial accelerometer (Kistler 8690C50).
Modal analysis for the structure is finished with ModalVIEW’s advanced mode estimation method based on mode stabilization diagram。The following figure shows the clear mode stabilization diagram from 48*3 measured FRF data.
The closely spaced modes can be selected from stabilization diagram. The real modes are kept with mathematical or faked modes being discarded. Part of the picked meaningful modes are listed in following table :
following figure displays the plot of synthesized FRFs
from estimated modes (red line) and measured original FRFs.
The synthesized FRFs should match original FRFs
well, which indicates that estimated modes are accurate enough.
One of the mode shapes is displayed as following :
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|Last updated April 28th, 2018|