Integrating transit signal priority with adaptive signal control in a connected vehicle environment

Source Organization:
University:Carnegie Mellon University
Principal Investigator:Stephen Smith
PI Contact
Project Manager:Courtney Ehrlichman
Funding Source(s) and Amounts Provided (by each agency or organization):$90,000
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Start and End Dates:January 2016 - January 2017
Project Status:Active
Subject Categories:Infrastructure-based Technologies
Abstract:This project aims at development of a more effective approach to transit signal priority (TSP) through integration of real-time adaptive signal control technology with DSRC-based detection of buses and communication of status information. We focus specifically on extending the Surtrac adaptive signal control system (in particular, the core intersection scheduling procedure) to achieve TSP objectives while at the same time minimizing the disruptive effects to overall traffic flow efficiency. Recent work with Surtrac has produced an intersection scheduling procedure that inputs weights reflective of the relative priority of vehicles and pedestrians, and uses these weights to generate signal timing plans that minimize the cumulative weighted delay of currently perceived incoming traffic flows. Taking this procedure as a starting point, we first investigate an extension that factors knowledge of bus stop locations and expected dwell times into Surtrac’s aggregate representation of traffic inflows to more accurately reflect bus arrival times at the intersection (as well as the arrival times of passenger vehicles that are likely to be blocked during dwell time at the bus stop). In Phase 2, we consider the added benefit of exploiting real-time bus status information, including such factors as bus schedule status (ahead or behind), bus occupancy, and bus door status (open or closed). In each of these two phases of the project, technology results will be evaluated first in simulation and then in the field. Field tests during both research phases will be carried out on the 24-intersection, DSRC-equipped test bed network that comprises the western end of the East Liberty Surtrac deployment.
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