La connaissance fine des pratiques cyclistes pose des problèmes méthodologiques particuliers, plus difficiles a résoudre que ceux concernant les piétons, ou les automobilistes. Pour rendre compte du découpage temporel des stratégies utilisées par le cycliste, la démarche adoptée a consiste à coupler les techniques utilisées pour analyser les trajets piétonniers avec celles utilisées pour étudier le comportement des conducteurs. Un vélo de ville léger a été équipé de quatre cameras miniaturisées reliées a un mixeur afin d'avoir les quatre images sur le même support avec la même base temporelle et d'un magnétoscope. Les données recueillies (vidéo et verbales) ont été traitées pour analyser l'organisation du déplacement et les stratégies mises en oeuvre par les cyclistes. L'expérimentation a porte sur les trajets habituels d'une vingtaine de cyclistes urbains (à Paris et à Lyon). English abstract: Means for understanding the specific behaviour and strategies adopted by cyclists in urban traffic, INRETS has undertaken research in the framework of the French "Ecomobility" project, using an experimental device, which enables the parameters traditionally employed in studies on motorist's behaviour to be observed and recorded on a bicycle. A city-bicycle has been equipped with four miniaturised video cameras, connected to a mixer - in order to have the four pictures on the same medium with the same time base - and to a videotape recorder. One camera films the cyclist's face, the second the view of the road in front, the third the view of the road behind and the fourth the speedometer. The experiment was carried out with volunteer cyclists on their usual daily trips. The observations have revealed that cyclists seek, to varying degrees, a certain efficiency in their travel, by limiting the number of stops they make to a minimum. In addition, the most complex tasks for cyclists occur when crossing intersections, where they must simultaneously take in visual information and carry out different manoeuvres. In more detail it was observed that cyclists adopt different methods for riding up a line of vehicles. It was also noted that cyclists travelling in a dense urban environment are required to avoid more obstacles (vehicles double parked, vehicles manoeuvring, stationary buses) that cyclists travelling in the outskirts. The results make it possible to envisage establishing a relationship between the different strategies adopted by the subjects and the characteristics of the journeys. (A)
Abstract