ISBN 978-3-540-755524 Google Scholar. Chung YT, Krebs DJ, Peebles JH (2001) Estimation of payload random vibration loads for proper structure design. Random Vibration is a varying waveform. Eq. (2.29) is not mathematically valid in the case of non-uniform flow because the power spectral density (PSD) of the excitation force, S F ω)(=2G(ω)) depends on the axial location along the tube. 2. Random Vibration Analysis. ISBN 0-471-58579-3 Google Scholar. Random vibration is also more realistic than sinusoidal vibration testing because random simultaneously includes all the forcing frequencies and “simultaneously excites all our product’s resonances.” ¹ Under a sinusoidal test, a particular resonance frequency might be found for one part of the device under test and at a different frequency, another part of the DUT may resonate. A random vibration analysis provides the likely structural response to a spectrum of random excitations. It does not refer to the physical quantity power such as watts or horsepower. Wirsching PH, Paez TL, Ortiz H (1995) Random vibrations, theory and practice. These pages were created to assist you when doing random vibration analysis. Wijker JJ (2008) Spacecraft structures. Sine and random vibration testing cannot be equated. Back to: Random Testing In vibration analysis, the PSD stands for the Power Spectral Density of a signal.Each word is chosen to represent an essential component of the PSD. Random vibration. Consider Tustin’s description of random vibration: “I’ve heard people describe a continuous spectrum (random vibration, VRC), say 10-2000 Hz as ‘1990 sine waves 1 Hz apart.’ No. It’s intensity is defined using a Power Spectral Density (PSD) spectrum. Random vibration consists of all the frequencies in a defined spectrum that are sent to the shaker at any given time. 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