Non-linear Free Vibration Identification via the Wavelet Transform
نویسنده
چکیده
This paper presents two time methods to identify weak non-linearities on damping and stiffness of a free vibrating system. Only the displacement is known. The first method is a direct parameter estimation method : using the measured displacement data of the system we obtain by numerical differentiation velocity and acceleration. A linear system containing the parameters is then derived. A least squares and a total least squares procedures are applied to obtain the physical parameters. The second method uses the wavelet transform : using the ridges and skeletons of the wavelet transform, we identify the parameters of the nonlinear vibrating system. These methods are applied to simulated single degree of freedom systems with nonlinearities on damping and stiffness.
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