Probability density function of whole-body vibration in passenger car

Abstract

This study identified the probability density function (PDF) model of the driver/passenger whole body vibration (WBV) in the passenger car based on wide in-situ measurements. The WBV was evaluated at the seat surface and feet of twenty-eight test vehicles travelled on test sections of different quality of total travel distance over 2,600 km. The WBV was quantified by the frequency-weighted acceleration at the driver’s/passenger’s seat surface and feet according to the ISO 2631-1 in three perpendicular axes. The lognormal PDF was identified as the most suitable model to fit empirical WBV data. Vibration data were divided in the groups according to the road roughness, vehicle speed, road and vehicle category. The results showed the marked influence of the road roughness and the lower influence of the vehicle speed, road and vehicle category on the PDF parameters. The linear relation between scale and shape parameters of PDF and road roughness level was estimated. The identified parameters of lognormal PDF can be useful for the basic statistics estimation of the WBV in passenger car and estimation of human ride comfort and health.