AN EVALUATION OF ROAD ROUGHNESS AND THE EFFECTS ON RIDING COMFORT AND VEHICLE DYNAMICS

The purpose of this paper is to evaluate the road roughness, its influence on riding comfort and to point out possible methods for understanding a correlation between road roughness and the resulting vehicle dynamics. First, statistical measurements of actual road roughness in summer and that in winter are carried out and its effect on riding comfort is discussed in comparison with ISO standard 2631. Based on the measurements, the road roughness characteristics can be represented by road roughness model functions. Second, regression analysis is used to investigate a linear relationship between the road profile elevation spectral density and the equivalent acceleration excitation to a vehichle. In addition, vibration source contribution method is applied to the prediction of the vibratory response of the vehicle from road roughness. As a result, significant results are obtained.