Assessment of Child Pedestrian Safety in School Zones: An UAV Driven Approach
摘要
The school going children are one of the most vulnerable groups of road users due to their lesser developed cognitive skills and small physical structure. During morning school drop-off and afternoon pickup times, a large volume of pedestrians and vehicles interact with each other within a shorter time frame. Thus, the children are often exposed to very risky situations. In developing countries like India, other factors like heterogeneous traffic conditions, lane indiscipline coupled with poor road infrastructure and enforcement aggravate the situation further. This paper presents a case study conducted in an Indian city for a typical school zone. To circumvent the limitation of data collection using a fixed camera setup, an Unmanned Aerial Vehicle, (UAV) was used for video data collection. The video data processing was done using advanced image processing techniques and computer vision. As the availability of crash data for safety assessment is an intricate issue for developing countries, proactive means of safety assessment have been utilized to evaluate the safety of children. Different surrogate safety indicators such as time-to-collision, post-encroachment time and instances of heavy braking were extracted to identify the conflict points within the selected school zone. Thresholds for mild and serious conflicts were verified using 85th percentile data. Further conflict maps and heatmaps were developed to get insights to the exact conflict locations. Significant differences between the morning and afternoon situations were observed. The findings emphasize on the utility of UAV technology in providing a comprehensive overview of traffic behavior and critical interactions in school zones. This study offers a detailed understanding of crash causal scenario in the school zone where child pedestrian crashes are prevalent. Further, it provides a methodology for an extensive safety assessment method, which can serve as an invaluable tool for traffic engineers, policymakers, and transport planners aiming to implement effective safety improvements around schools.