Project Title: Detection-Control System for Rural Signalized Intersections

Sponsor: Texas Department of Transportation

Principle Investigator: Jim Bonneson

Research Staff:

TTI Project Number: 440222

Start Date: 9/1/00

End Date: 8/31/02

Abstract: Commonly used detection-control systems at isolated, high-speed intersections are designed to extend the phase in service until the approach "dilemma zone" is clear of all vehicles. However, This system has several limitations. They include: (1) dilemma zone protection is eliminated whenever the phase reaches its maximum green duration, (2) system operation is not sensitive to the type of vehicle in the dilemma zone (e.g., car, truck), (3) system operation is not sensitive to the amount of delay experienced by motorists desiring service via other phases, and (4) system is costly in terms of the number of detectors needed along the intersection approach. The objective of this research project is to develop and test an economical detection-control system that is capable of minimizing both delay and crash frequency at rural intersections. A two-year program of research is proposed that will satisfy this objective. The approach to be taken in this research is to develop and tes t an intelligent detection-control system at two rural intersections in Texas. Before-and-after studies will be conducted to measure the system's effect on delay, stops, conflicts, and accident frequency. At the conclusion of the proposed research project, a Design Guidelines and a Specifications Document will be developed to facilitate implementation of the recommended system.