Design and Evaluation of an Intelligent Dilemma-Zone Protection System for a High-Speed Rural Intersection

Abstract

This paper presents the design and evaluation of a dilemma-zone protection system that uses dynamic detection technology to track individual vehicles as they approach an intersection of interest. A high-speed rural intersection in Maryland experiencing a high crash frequency was selected for system installation and evaluation. Data were collected from three sensors designed specifically for tracking individual vehicles and deployed along the target approach. The sensors were used in real time to control the signal logic and provided green or all-red extensions when the predefined parameters of detected vehicles were met. A field test was conducted to evaluate the performance of the system design and the effectiveness of the associated parameters. The data analysis included the identification of falsely called red extensions (related to efficiency) and missed red extensions (related to safety) to assess the overall performance of the newly installed system. The field observation results indicate that the newly designed dynamic dilemma-zone protection system using an all-red extension offers distinct advantages over traditional systems by providing additional protection to highspeed vehicles even when they are in the “cannot go” zone and make an incorrect decision to go.