Synthesizing Nonstationary, Non-Gaussian Wheeled Vehicle Vibrations

This paper presents a novel technique by which non-Gaussian vibrations are synthesized by generating a sequence of random Gaussian processes of varying root-mean-square (rms) levels and durations. The technique makes use of previous research by the authors which shows that non-Gaussian vibrations from wheeled vehicles comprise of a sequence of Gaussian segments. Synthesis is achieved by creating a modulation function which is then applied, by means of a purposed-designed amplifier module, to a Gaussian random signal itself generated by a standard laboratory random vibration controller. This technique yields nonstationary, non-Gaussian random vibrations that statistically conform to the desired spectral and statistical (rms) distribution functions and are typical of those generated by wheeled vehicles. Results from experiments using such a Statistical Vibration Synthesizer system demonstrate the effectiveness of the method and its relevance for evaluating the effects of nonstationary random vibrations on consignments and passengers alike.