Introduction

Method for the identification of modal parameters (resonance frequencies, damping factors, and modal vectors) of a road or rail vehicle in steady operation, by a smart processing of the outputs of the system (displacements, velocities, or accelerations), measured in defined sensor locations. The invention allows moreover, for the indirect characterization of the statistic properties of road surfaces or railway tracks, which the vehicle is in contact with whilst moving.

Technical features

The invention is a method for the identification of modal parameters (resonance frequencies, damping factors, and modal vectors) of a road or rail vehicle in steady operation. In particular, it reviews the classical theory and provides a specialized mathematical model describing the interaction between road surfaces or railway tracks and the vehicle. It is possible to use the outputs of the sensors supplied by the manufacturer or applied for the road tests: the invention provides fitting algorithms to extract from these outputs the vehicle modal parameters and statistical properties of roads/railway tracks.

The invention will make available a novel family of simple and cost-effective tools for the estimation of modal parameters of road and rail vehicles needed to achieve: (i) vehicle dynamic identification; (ii) assessment of vehicle suspension performance; (iii) identification of chassis structural modes; (iv) vehicle structural health and condition based monitoring; (v) indirect characterization of statistical properties of roads and railway tracks.

Possible Applications

• Railways and roads;
• Road and railway transportation vehicles manufacturers;
• Service industry for maintenance of roads and railway tracks;
• Manufacture of vehicles for agriculture.

Advantages

• Need to measure system outputs only;
• Reliable evaluation of modal parameters and road profiles;
• Usage of sensors already available on the vehicle;
• Simple and cost effective tool;
• Evaluation of vehicle dynamic in real working conditions.