On-the-road Measurements to Establish the Dynamic Characteristics of Transport Vehicles

摘要

This paper deals with a proposed approach to estimate the dynamic characteristics of road vehicles using only on-the-road response data. Previous work undertaken by the authors was ultimately unable to be validated as the actual pavement elevation profile traversed by the single-wheeled, idealized vehicle was unknown. In order to address this, the single-wheeled vehicle used by the authors was instrumented to operate as an inertial profilometer in order to measure the actual longitudinal pavement elevation profile to establish the transmissibility frequency response function of the vehicle during operation. The on-the-road transmissibility frequency response functions were compared with those established in the laboratory (using a large-scale vibration table) and found to significantly differ, particularly in the level of damping of the sprung mass mode (body) of the vehicle. The unsprung mass mode (axle-hop) resonant frequency is also consistently observed to shift to a lower frequency during operation (on-the-road). Two approaches are outlined to estimate the spectral exponent of the assumed pavement elevation spectral model but were found to yield inaccurate results because of the variation in the pavement profiles travelled by the vehicle during each experimental run. The in-built profilometer revealed that it is incorrect to use an assumed spectral model for the excitation as it is unable to accurately represent the actual pavement spectrum travelled over by the vehicle. Copyright (c) 2015 John Wiley & Sons, Ltd.