The research of dynamic characteristics of a vehicle driving over road roughness

Abstract

The paper analyses the effect of road roughness on the variation of the vertical oscillations’ frequency of the sprung and unsprung masses of a vehicle driving at varying speed. The research aims to determine the regularity with which the wheel of a vehicle moving at varying speed reproduces the roughness of road pavement texture. The theory of mathematical statistics is used to define the distribution law of road defects measured during the experiment. In the present investigation, the displacements of the wheel and suspension of the vehicle, driving at varying speed over the defects of the selected road section pavement, have been evaluated. Based on the frequency characteristic obtained from the measured data, the frequency variation of the displacements of the sprung and unsprung masses in a vehicle moving on a rough road has been determined. The vertical acceleration of the wheel and the body of a vehicle has been measured, and the frequency characteristic of vertical acceleration of the sprung and unsprung vehicles’ masses has been analysed. The schematic view of the wheel’s axis displacement model is presented.