Passenger Car Vibration Dose Value Prediction Based on ISO 8608 Road Surface Profiles

This study aimed to evaluate the relation between measured vibration dose value (VDV) in passenger car and road unevenness power spectral density (PSD). Measurements were taken on the passenger seat surface and feet in three axes. Nine test cars (small/large family cars, city car, SUV, and van) were used. The relation between VDV and road PSD in 200-m segments was estimated. Measured total VDV was fitted by a function of road spectrum parameters and vehicle speed. Fitting parameters were estimated for three road categories and particular test vehicles. Road profiles in C road class according to ISO 8608 may induce the vibration higher than the VDV exposure action value, 9.1 m/s^1.75, in 80.2% of cases and the VDV exposure limit value, 14.8 m/s^1.75, in 22% cases. The critical vehicle speed was calculated as a function of the road PSD parameters and VDV exposure action and limit values. Road class C profiles should be used in simulation for relatively low speeds to not exceed the VDV limit values. A low contribution ~3% of foot vibration to the total VDV was observed. The horizontal vibration on the seat surface contributes by ~10% to the total VDV on the seat surface. The significant variability among test vehicles in total VDV with relative range up to 50% was observed.