Evaluation of Vehicle Detection Systems for Traffic Signal Operations

Abstract

Typical vehicle detection systems used in traffic signal operations are composed of inductive loop detectors. Because of costs, installation challenges, and operation and maintenance issues, many alternative nonintrusive systems have been developed and are now commercially available. Field-testing was conducted to evaluate nine alternative vehicle detection systems (four video, two radar, one thermal, and two hybrid) at the stop-bar zone of a signalized intersection under varying time-of-day and weather conditions: (1) daytime versus nighttime; and (2) favorable versus windy, rainy, or snowy conditions. The systems were set up for two detection zones: one for the through and right-turn movements and one for the left-turn lane. Based on the results of this study, no single system universally performs best. Depending on a specific time of day or weather conditions, several of the system types tested could claim that their technology outperforms all others. However, based on the percentage of false and missed detections, all of the products representing different system types exhibit opportunities for improvement and enhancement.