Non-Gaussian Random Vibration Test by Control of Multiple Correlation Coefficients, Skewnesses, and Kurtoses

Abstract

Non-Gaussian random vibrations have gained more attention in the dynamics-research community due to the frequently encountered non-Gaussian dynamic environments in engineering practice. This work proposes a novel non-Gaussian random vibration test method by simultaneous control of multiple correlation coefficients, skewness, and kurtoses. The multi-channel time-domain coupling model is first constructed which is mainly composed of the designed parameters and independent signal sources. The designed parameters are related to the defined correlation coefficients and root mean square values. The synthesized multiple non-Gaussian random signals are unitized to provide independent signal sources for coupling. The first four statistical characteristics of the synthesized non-Gaussian random signals are theoretically derived so that the relationships among the generated signals, independent signal sources, and correlation coefficients are achieved. Subsequently, a multi-channel closed-loop equalization procedure for non-Gaussian random vibration control is presented to produce a multi-channel correlated non-Gaussian random vibration environment. Finally, a simulation example and an experimental verification are provided. Results from the simulation and experiment indicate that the multi-channel response spectral densities, correlation coefficients, skewnesses, and kurtoses can be stably and effectively controlled within the corresponding tolerances by the proposed method.