Modal testing is a form of vibration testing of an object whereby the natural (modal) frequencies, modal masses, modal damping ratios and mode shapes of the object under test are determined.
A modal test consists of an acquisition phase and an analysis phase. The complete process is often referred to as a Modal Analysis or Experimental Modal Analysis.
There are several ways to do modal testing but impact hammer testing and shaker (vibration tester) testing are commonplace. In both cases energy is supplied to the system with a known frequency content. Where structural resonances occur there will be an amplification of the response, clearly seen in the response spectra. Using the response spectra and force spectra, a transfer function can be obtained. The transfer function (or frequency response function (FRF)) is often curve fitted to estimate the modal parameters; however, there are many methods of modal parameter estimation and it is the topic of much research.
Other articles related to "modal testing, testing, modal":
... Several input signals are available for modal testing, but the sine sweep and random frequency vibration profiles are by far the most commonly used signals ... or the stinger, the object responds the same way as impact testing, by attenuating some and amplifying certain frequencies ... These frequencies are measured as modal frequencies ...
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