Interaction between car drivers and vulnerable road users at roundabouts

Abstract

Roundabouts represent one of the most used road intersection. The reduction of conflict points between trafficflows, associated with the moderation of the driving speed, in fact, makes them preferable to signalizedintersections. However, great attention should be paid to bicycle and pedestrian paths present in the roundabout, because incidental statistics show that not always secure accessibility of these vulnerable users is ensured. According to this, the design approach of roundabouts must consider not only the transportation aspects, but also the drivers' behavior. Their mechanisms of understanding, recognition and decision, in fact, heavily influence the mutual interaction with pedestrians and cyclists. Furthermore, considering that users widely scan with eyes the surrounding environment during the driving task, searching for the relevant information on their spatial and temporal position, is crucial to consider which elements of the road environment are seen and considered by drivers, in order to design roundabouts that are safe for all categories of users. This paper reports the results of an experimental test, which involved a sample of drivers who have traveled by car along a road section including two roundabouts. By an innovative eye tracking equipment, able to track the eye movements (saccades), the sight point of the drivers' eye and their visual behavior in entering, circulating and exiting from the roundabouts have been analyzed. The interaction with non-motorized users was focused, obtaining useful information for the design of cycling and walking paths in these intersections.