Natural frequency and damping?

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Gianluca Argentini

Dear Mojtaba, try applying a Fourier Transform to signal, you should give the fundamental frequency associated to your data. This value is the frequency of system "body with damping", therefore it could not be the real natural frequency of body. See reference below, Chap. 4, for damping effect. Gianluca

J.P. Den Hartog, Mechanical Vibrations

Hauke Gravenkamp

Dear Mojtaba,

I performed a Fourier transform of your data but it appears to be all noise. I cannot see any distinguishable frequency.

Regards,

Hauke

Mojtaba Dargahi

thanks all