Daniel Stanczyk’s scientific contributions

The knowledge of heavy traffic on the road network presents a strategic interest for the road operators, in order to:- increase mobility by adapting their policies to the traffic,- optimise the life expectancy of road surface and bridges,- improve safety.This implies the collection of the following data: number, time distribution, type (defined by the number of axles), speed, and weight.The traditional systems are able to count the vehicles and to measure the HGV's speed. However, the control of overloaded HGV was made randomly and the vehicles were stopped and weighed on parking areas. This method caused congestion and its efficiency was limited.As a result, no significant data was available on the HGV's type or weight and the knowledge on heavy traffic was restricted to time distribution and speed. To improve the national database on heavy traffic and to develop a new control method for overloaded HGV, the French Ministry of Transport defined a detection system based on weighting equipments and automatic number plate recognition (ANPR). The detection systems are connected to a national database, which can be give real-time information on the heavy traffic or be used for statistics.Today, around 25 detection systems are installed on the structural road network, fulfilling the following objectives:- building a national database on heavy traffic,- preselecting and identifying overloaded HGV to make controls on parking areas more efficient,- developing specific traffic management measures,- identifying, via ANPR, transporters regularly in breach with the law to make specific controls in the companies.In a first part, the presentation will describe the detection system (material, sensors, hardware and software) and its deployment on the French road network.In a second part, the presentation will be focused on the results, their precision, the first extractions made on the national database, and the global efficiency of the system.

This paper reports the research works done by IFSTTAR and CETE de l'Est to take into account vehicle lateral position effect on road sensor Weigh-In-Motion (WIM) accuracy. The considered WIM sensors are piezoceramic strip sensors. Different methods and their results are discussed. Refinement of automated calibration process is first studied, then an off-centered vehicle sorting out method is introduced, and finally a signal processing method is used. These results partially confirm previous theoretical and lab studies, and lead to a significant improvement of the WIM accuracy by removing the bias due to the wheel lateral position. Résumé Cet article présente les travaux de recherche réalisés par l'IFSTTAR et le CETE de l'Est sur la compensation de l'influence de la position latérale du véhicule sur la précision d'un système de pesage en marche utilisant des barreaux piézo-céramiques. Plusieurs méthodes et leurs résultats sont présentés. L'amélioration de la procédure d'étalonnage automatique est la première piste étudiée, puis la détection et l'élimination de véhicules excentrés dans la voie, et enfin une méthode de compensation directe des pesées. Ces résultats confirment en partie les précédentes études théoriques et menées en laboratoire, et conduisent à une nette amélioration de la précision des pesées par compensation des erreurs liées à aux roues excentrées. Mots-clefs: Pesage en marche (WIM), capteurs, piézo-céramique, position latérale des roues et du véhicule, précision, poids lourds.