01628109

Component

This paper studies intersection signal control in which traffic arrivals from all approaches along with the queuing situation are assumed known. The optimal control policy minimizes the overall intersection delay by deciding the green intervals for signal phases dynamically as driven by real-time traffic but subject to a set of constraints. The set of constraints allow consideration of practical factors such as min/max green time for each phase and may be flexibly pre-defined. This paper proposes an analytical model for intersection vehicle delay and derives optimal conditions for green signal switch. Two numerical algorithms are proposed: optimum based (DORAS) and queue-based heuristic respectively. Numerical tests are conducted via simulation using an actual intersection data covering peak hours, mid-day hours and night hours. With a fixed sequence of phases, the tests show an up to over 20 percent reduction of average vehicle delay due to our proposed algorithm compared with the fully actuated control. This research prepares a new concept for the signal control problem in a cyber-enabled environment.

This paper was sponsored by TRB committee AHB25 Standing Committee on Traffic Signal Systems. Alternate title: Dynamic Optimal Real-Time Algorithm for Signals: Case of Isolated Roadway Intersections.

01618707

17-01496

English

23p

2017

Transportation Research Board 96th Annual Meeting

Digital/other

Figures; References; Tables

Algorithms; Isolated intersections; Phasing by right of way; Signalization; Signalized intersections

Highways; Operations and Traffic Management

Transportation Research Board Annual Meeting 2017 Paper #17-01496

TRIS, TRB, ATRI

Dec 8 2016 10:29AM