抄録
Detecting crack by using the cross correlation function of the measured vibration responses was carried out. A fast and easy check of machine parts is necessary for mass-production. The method of a fast and easy check of machine parts need (1) simple hold method for clamping the test piece and (2) fast signal processing. In this study, we pay attention to (2) fast signal processing. Real crack in the machine parts was treated as two-dimensional crack model. Test piece size and crack size were varied. Natural frequency of first bending mode was obtained by period derived from result of the cross correlation function. And also, natural frequency of first bending mode was obtained by the result of Fast Fourier Transform (FFT). Natural frequency was changed by test piece size and crack size. Distribution of the natural frequency can be confirmed clearly by the result derived from the cross correlation function.
