Estimation of road transport vehicle dynamic characteristics using random decrement analysis and on-the-road vibration data

This paper presents the application of a recently developed and validated approach to accurately estimate the sprung mass mode dynamic characteristics of road transport vehicles using only on-the-road vertical vibration response data during constant speed operation. A description of the developed analytical approach using the random decrement technique and the Hilbert transform is included. Three experimental case studies are presented, each using a different road transport vehicle travelling at various nominally constant operating speeds over different roads to demonstrate the ability of the on-the-road approach to practically estimate the sprung mass modal properties, namely natural frequency and damping. The estimated dynamic characteristics were compared with different experimental procedures currently in use, including response-only (transient), and excitation-response methods. The new method provides a simpler, cost effective, and practical approach to obtain reliable and realistic estimates of the sprung mass mode natural frequency and damping ratio