This paper describes the application of non-intrusive modal test techniques using a scanning laser vibrometer on a cantilevered plate. Modal test results are presented for a wing-shaped cantilevered plate tested with a continuous scanning laser vibrometer and non-contacting, sine-dwell excitation. Results are also presented for the plate from a free decay test method which employs step scanning single-point sensing with non-contacting chirp excitation. Sensing was done with accelerometers, but the method is proposed for use with a step scanned laser vibrometer. Modal parameters were estimated in the time domain from free decay responses. Results are in good agreement with those from a finite element model and a conventional forced response test using accelerometers and a shaker.
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