Project Title: Improved Operation of Traffic Signal Controllers at Isolated Intersections

Sponsor: Texas Department of Transportation

Principle Investigator: Nadeem Chaudhary

Research Staff: TTI

Project Number: 443042

Start Date: 9/1/01

End Date: 8/31/02

Abstract: In most urban areas of Texas, it is not uncommon to encounter traffic signals operating under isolated control. Many of these signals are located near adjacent signals, and their operational efficiency significantly reduces when platoons of traffic from an adjacent signal begin to arrive. Detectors installed at these signals for providing actuated control, are currently unable to detect platoons and are incapable of assign priority to higher demand approaches. As a result, most of these platoons are forced to stop in order to serve a few (sometimes only one) vehicles on a conflicting approach. This causes significant delay and stops to high-priority vehicles. This research project has been requested by TxDOT to develop an intelligent traffic control system that is capable of: 1. Demand detection, 2. Platoon detection, and 3. Controller manipulation to accommodate the detected platoon/demand. Additional objectives of this research project are to: · install and test the deve loped system at two selected sites in Texas; · provide benefit-cost analysis using before-and-after field studies; and · develop guidelines for installing future systems.