Bidirectional cycle tracks in Valencia (Spain) are usually placed between pedestrian sidewalk and motor vehicle parking. They are separated from the other users by a line, a line of trees, hedges or a curb. Bicyclists should yield to pedestrians at some points. Using an instrumented bicycle provided with four cameras, four rangefinders, a laser pointer, a microphone and a GPS tracker, every conflict occurring with vehicles or pedestrians was analysed. The main Traffic Conflict Techniques (TCT) parameters such as Time to Collision (TTC), Conflicted Speed (CS) or Post Encroachment Time (PET) and a subjective risk perception for every conflict were obtained. Conflicts were classified as “static objects”, “wrong circulations” (pedestrians or motorbikes circulating on the cycle track), and “crossings”, which could be law-compliance or not, depending on the location. 650 conflicts (70% pedestrians) were studied in 6 different cycle tracks in Valencia. 10 hours of video were recorded on a 130 km stretch. The study showed that is possible to detect conflicts (and to obtain the main TCT parameters) from a bicycle in movement allowing the researchers to create maps of conflicts and detection hotspots. The analysis compared each location by the number of conflicts per kilometre. By studying the TCT parameters, a relation between TTC, CS and subjective risk perception was founded, but it was not with PET, mainly in bicycle-pedestrian crossing conflicts. (Author/publisher)
Samenvatting