Models for Quantitative Assessment of Video Detection System Impacts on Signalized Intersection Operations

in length and width than their actual size. The perceived larger vehicle size can also result in various occlusion scenarios (5–7). Occlusion of a detector can result in increased detector occupancy and false detections when no vehicles actually exist at the detector location. Occlusion of a following vehicle can also result in missing detections. Several studies have been conducted regarding video detection system applications at signalized intersections. Abbas and Bonneson (8) developed a set of guidelines on deployment of video detection systems at signalized intersections, including detection design and configuration for design speeds less than 60 mph. A model to calibrate the effective vehicle length by the video systems was presented. Zheng et al. (9) applied video detection systems to detect cycle failures at signalized intersections. Applications of video detection systems have also been attempted to measure vehicle delay and other performance measures at signalized intersections (10–13). Grenard et al. (14) evaluated the performance of video detection systems at signalized intersections from the point of view of comparing differences in detector occupancy between video and inductive loops. Tian et al. (2) developed a model to calibrate the perceived detector location by video detection systems based on various geometric elements. Potential applications of the model were cited, but no detailed quantitative evaluations were conducted. A set of models is provided that can be applied to conducting quantitative evaluations of various issues related to video detection system applications at signalized intersections. It is not the intent of the authors to provide general quantitative results of the impacts but rather to provide modeling tools and to demonstrate their applications if case-specific analyses are desired. The models focus on addressing various occlusions and their potential impact on signal operations, including the impact on actuated signal operations, advance detection, missing detection, and false detection.