Experimental Modal Analysis by Using Hilbert Transform of Signal from Continuous Scanning Laser Vibrometer

연속 스캐닝 레이저 진동계 신호의 Hilbert 변환을 이용한 실험적 모드 해석

  • 강민식 (경원대 공대 기계공학과) ;
  • 장태규 (중앙대 공대 전기전자공학부) ;
  • 김호성 (중앙대 공대 전기전자공학부)
  • Published : 2002.06.01

Abstract

This paper deals with the vibration deflection shape measurement technique for a sinusoidally excited structure using a continuously scanning laser Doppler vibrometer (CSLV). The CSLV output signal is an amplitude-modulated vibration in which the excitation signal is modulated by the deflection shapes, and thus the deflection shapes of vibration defined along a scan line can be derived by the envelop and the phase information of the CSLV output signal. In this work, a Hilbert transform based approach has been proposed for measurement of deflection shapes. This technique is as simple as the demodulation technique and allows more convenient experimental settings than the Fourier transform approach. The feasibility of the proposed technique is illustrated along with results of experiment.

Keywords

References

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