Abstract:
Ride comfort, suspension working space and road holding are three important indices to evaluate the dynamic performance of vehicles. The object of this paper is to develop the analytical model and numerical solution procedure of dynamic performance indices of vehicles with uncertainty in system parameters and road conditions. A quarter car model is used to describe the dynamic behavior of vehicles running on randomly profiled roads. The sprung mass, unsprung mass, suspension damping, suspension and tire stiffness are considered as random variables. The road irregularity is considered as a Gaussian random process and modeled by means of a simple exponential power spectral density. The mean value, standard deviation and variation coefficient of the vehicleâ¿¿s natural frequencies and mode shapes are obtained by using the Monte-Carlo simulation method. The computational expressions for the numerical characteristics of vehicleâ¿¿s dynamic performance indices in frequency domain are developed by means of the random variableâ¿¿s functional moment method and algebra synthesis method. The influences of the vehicleâ¿¿s parameters on the vehicleâ¿¿s dynamic performance indices are investigated using a practical example, and some useful conclusions are given.
