A time-domain procedure for non-Gaussian stationary environmental testing using zero-memory nonlinear transformation. (13th January 2020)

• Record Type: Journal Article
• Authors: Cui, Song; Zheng, Enlai; Kang, Min
• Is Part Of: Journal of vibration and control. Volume 26:Number 15/16(2020)
• Page Start: 1197
• Page End: 1213
• Publication Date: 2020-01-13
• Subjects: Time-domain procedure -- non-Gaussian -- zero-memory non-linear transformation -- finite impulse response filter -- kurtoses; Vibration -- Periodicals; Damping (Mechanics) -- Periodicals; 620.3
• DOI: 10.1177/1077546319894853
• Languages: English
• ISSNs: 1077-5463

Abstract

This article proposes a time-domain procedure for a non-Gaussian stationary random vibration test with prescribed power spectral densities. Previous procedures for generating non-Gaussianity suffered from certain defects. For example, zero-memory nonlinear transformation, an algorithm frequently applied to transform Gaussian signals into non-Gaussian signals, often produces changes in both auto-power spectral densities and cross-power spectral densities, which might result in control instability under certain circumstances. In this article, the authors propose a different approach for the zero-memory nonlinear function. First, a time-domain procedure for a non-Gaussian random test is introduced. Second, a rescaling method is applied to correct the magnitude amplification on the auto-power spectral density because of zero-memory nonlinear transformation. We offer experience formulas in this method to adjust the auto-power spectral density of both super-Gaussian and sub-Gaussian responses. Third, a control strategy using a finite impulse response filter is proposed to further improve the auto-power spectral density if the shape of the auto-power spectral density is distorted. The kurtosis loss induced by the filtering process is also analysed and a corresponding solution is put forward to ease the reduction. Numerical test and a biaxial shaker table test are conducted to validate the availability and superiority of the proposed procedure.