Abstract： A method was presented for evaluating evolutionary power spectral density (PSD) responses of vehicle to random road excitations in spatial frequency-time domain. The stochastic road excitation was modulated in accordance with an integral transform, the PSD formulas of road excitations and vehicle responses was derived corresponding to the certainty relationship between traveling distance and duration, and the PSD responses of stochastic road vehicle was predicted using simulation result of certainty vibration in real field. The PSD matrix of road excitations and some computer simulated results of road four-wheel cars in spatial frequency-time domain were given. The results showed that: if only the traveling distance is a certainty function of duration, the spatial stationary excitations of road may be converted into an evolutionary random process in time domain; this method is feasible for predicting evolutionary PSD responses of road vehicles in real field.
2012, Vol. 31 
