An Experimental Test Bed for Developing High-Rate Structural Health Monitoring Methods

Figure 5

Results from the mass drop experiment. (a) Diagram of the mass dropping from the beam. (b) Amplitude of the discrete Fourier series (DFS) of the tip acceleration. (c) Time history of the tip acceleration. (d) Spectrogram of the tip acceleration when the mass drops. The horizontal dashed lines indicate the frequencies for the first natural frequency with and without the added mass.

(a)

(b)

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(d)