Friday Seminar – Eleni Christofa on Traffic Signal Optimization with Transit Priority

light rail tracks and wires, October 23, 2005

This Friday’s TRANSOC Seminar has Eleni Christofa, Ph.D. Candidate, University of California, Berkeley, presenting "Traffic Signal Optimization with Transit Priority."

Traffic responsive control with transit signal priority (TSP) is a strategy that is increasingly used to improve transit operations in urban networks. However, none of the existing real-time signal control systems has explicitly incorporated the passenger occupancy of transit vehicles in granting priority, or has effectively address issues such as the provision of priority to transit vehicles traveling in conflicting directions at signalized intersections. A person-based traffic responsive signal control system with TSP is presented that provides priority to transit vehicles while minimizing the negative impacts on the auto traffic even when transit vehicles travel in conflicting directions. The objective is to minimize the total person delay at the intersection by explicitly considering the vehicles’ occupancy and schedule adherence. Such a system has been made feasible by advanced technologies which provide real-time information such as Automated Vehicle Location systems and passenger counters.

The proposed traffic responsive signal control system was first developed for isolated intersections, and extended to arterial signalized networks.  Evaluation tests for a wide range of traffic and transit operational characteristics show that the proposed system can achieve substantial reductions in transit delays with no significant increase in auto delays, and can outperform signal settings provided by commonly used optimization tools that minimize vehicle delays. The contribution of this research is the development of readily implementable strategies that take advantage of existing infrastructure to improve transit and traffic operations in congested metropolitan areas.

The seminar will be held Friday, March 16, from 4:00-5:00 p.m. in 534 Davis Hall. Please join us for a TRANSOC-sponsored Cookie Hour in the ITS Library from 3:30-4:00 p.m.