Multi-exciter stationary non-Gaussian random vibration test with time domain randomization. (1st May 2019)

• Record Type: Journal Article
• Authors: Zheng, Ronghui; Chen, Huaihai; Vandepitte, Dirk; Luo, Zhengbo
• Is Part Of: Mechanical systems and signal processing. Volume 122(2019)
• Page Start: 103
• Page End: 116
• Publication Date: 2019-05-01
• Subjects: MIMO vibration test -- Random non-Gaussian vibrations -- Kurtosis control -- Skewness control -- Time domain randomization; Structural dynamics -- Periodicals; Vibration -- Periodicals; Constructions -- Dynamique -- Périodiques; Vibration -- Périodiques; Structural dynamics; Vibration; Periodicals; 621
• DOI: 10.1016/j.ymssp.2018.12.013
• Languages: English
• ISSNs: 0888-3270

Abstract

Highlights: High computational efficiency of non-Gaussian vibration control is emphasized. Relationships between reference skewnesses, kurtoses and spectra are revealed. Limitation of the setting of reference kurtoses and skewnesses are discussed. Results from a numerical simulation and an experimental test are provided. Abstract: This paper presents a new control method for multi-input multi-output stationary non-Gaussian random vibration test using time domain randomization. The control objectives are composed of response skewnesses, kurtoses and power spectral densities. The generation process of stationary and coupled reference non-Gaussian signals by specified reference skewnesses, kurtoses and spectra is analyzed. The reference non-Gaussian signals combined with system frequency response functions are then utilized to obtain the desired drive signals for dynamic inputs, in which the inverse system method in the frequency domain is employed. The primary advantages of the proposed methods are the high computational efficiency and simultaneous control of the time-frequency characteristics of response signals. In consideration of system cross coupling characteristics manifested in coherence and phase coefficients, the skewness and kurtosis tuning steps for each control channel are formulated by using a sequential phase modification method. The relationships between reference skewnesses, kurtoses and spectra are discussed and they reveal that the reference spectra have an influence on the settings of reference skewnesses and kurtoses, which implies that proper settings of reference skewnesses, kurtoses and spectra are necessary. A numerical example and a triaxial vibration test are provided and the results show the validity and feasibility of the proposed method.