The development of an automatic method of safety monitoring at Pelican crossings

Abstract

This is an author produced version of an article published in Accident and Analysis Journal. It has been peer reviewed but does not contain the publishers formatting or pagination. AbstractThis paper reports on the development of a method for automatic monitoring of safety at Pelican crossings. Historically, safety monitoring has typically been carried out using accident data, though given the rarity of such events it is difficult to quickly detect change in accident risk at a particular site. An alternative indicator sometimes used is traffic conflicts, though this data can be time consuming and expensive to collect. The method developed in this paper uses vehicle speeds and decelerations collected using standard in-situ loops and tubes, to determine conflicts using vehicle decelerations and to assess the possibility of automatic safety monitoring at Pelican crossings. Information on signal settings, driver crossing behaviour, pedestrian crossing behaviour and delays, and pedestrian-vehicle conflicts was collected synchronously through a combination of direct observation, video analysis, and analysis of output from tube and loop detectors. Models were developed to predict safety, i.e. pedestrian-vehicle conflicts using vehicle speeds and decelerations.

Development and Implementation of a Vehicle–Pedestrian Conflict Analysis Method

“…Taking specific examples of the former case, the so-called "US method" for traffic conflicts is used in (19) to model the interaction between left-turning vehicles and pedestrians at signalised intersections and the STCT is applied in (20) to assess the efficiency of the safety regulations for vulnerable road users at intersections in Beijing. Regarding new techniques, an early pedestrian conflicts technique is described in (21), involving the qualitative categorisation of conflict types and severity, and quantitative methods are presented in (22) and (23), where speeds and decelerations are used to quantify pedestrian conflicts at Pelican crossings and left-turn situations respectively. The analysis process is also automated in the latter two studies, using pneumatic tubes in (22) and a video detection technique in (23).…”

“…Regarding new techniques, an early pedestrian conflicts technique is described in (21), involving the qualitative categorisation of conflict types and severity, and quantitative methods are presented in (22) and (23), where speeds and decelerations are used to quantify pedestrian conflicts at Pelican crossings and left-turn situations respectively. The analysis process is also automated in the latter two studies, using pneumatic tubes in (22) and a video detection technique in (23).…”

Analysis of Pedestrian–Vehicle Traffic Conflicts in Street Designs with Elements of Shared Space

“…However, some examples of work on conflicts between vehicles and other road users can be found in the literature, mostly for the purpose of assessing the safety of pedestrian crossings and the interactions within mixed traffic flows. These include: (24), where a method categorising vehicle-pedestrian conflicts at crossings into one of 13 types was derived with a view of identifying potential safety hazards; (25), where pedestrianvehicle conflicts along with traffic characteristics data were used to perform automated assessment of the safety of Pelican crossings in the UK; and (26)(27), in which an automated video analysis system to classify road users as vehicles or pedestrians, identify conflict situations between them and categorise them according to their severity was developed. Also, there are several instances of methods adapted from well-established vehicle-vehicle methods to monitor pedestrian-vehicle conflicts, such as: the application of the STCT in (28) and (29); the use of the USDoTCT in (30); and the adaptation of the CIHTCT in (12) and in (31).…”

Requirements of a system to reduce car-to-vulnerable road user crashes in urban intersections

“…However, STRADA and SafetyNet databases do not contain this information as such, nor even information from which it can be deduced. For this study, therefore, data from a study by Malkhamaha et al (2005) were used. They state that applied deceleration, relative to other conditions, is mostly affected by perceived situation urgency and may be expressed as a function of time to collision.…”