The paper presents a technique for experimentally generating non-Gaussian random forced vibrations of linear and nonlinear mechanical models mounted on the platform of an electrodynamic or ervohydraulic shaker. The method proposed implies generation of pseudo-random excitation in the form of a Fourier expansion which is a commonly accepted approach to simulate Gaussian random excitations for the shaker testing. The non-Gaussian solution obtained invokes a kurtosis value as a basic control parameter in addition to usual power spectrum fitting. Simulation in the probability distribution domain is based on an analytical expression derived for the kurtosis parameter of the polyharmonic process in term sof amplitudes and phase angles for any number of harmonic components. An experimental study has been carried out for a cantilevered beam model and an iterative technique was used to compensate for the influence of the shaker and test item dynamics affecting the kurtosis and spectral characteristics of the response.
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