Integrated transit priority and rail/emergency preemption in real-time traffic adaptive signal control

Pitu B. Mirchandani, David E. Lucas

Research output: Contribution to journalArticlepeer-review

33 Scopus citations


The article discusses a strategy, referred to as Categorized Arrivals-based Phase Reoptimization at Intersections (CAPRI), which integrates transit signal priority and rail/emergency preemption within a dynamic programming-based real-time traffic adaptive signal control system. The system takes as input sensor data, from detectors, automatic vehicle locators, transponders, etc., for real-time predictions of traffic flow, and "optimally" controls the flow through the network using signal phasing. The system utilizes a traffic adaptive signal control architecture that (1) decomposes the traffic control problem into several suhprohlems that are interconnected in a hierarchical fashion, (2) predicts traffic flows, at appropriate resolution levels (individual vehicles, platoons of vehicles, transit vehicles, emergency response units, and trains) to enable proactive control, (3) supports various optimization modules for solving the hierarchical subproblems, and (4) utilizes data structure and computer/communication approaches that allow for fast solution of the subproblems, so that each decision can be implemented in the field within an appropriate rolling time horizon of the corresponding subproblem. Simulation-based analyses illustrate the effectiveness of the CAPRI system.

Original languageEnglish (US)
Pages (from-to)101-115
Number of pages15
JournalJournal of Intelligent Transportation Systems: Technology, Planning, and Operations
Issue number2
StatePublished - Apr 1 2004
Externally publishedYes


  • Emergency preemption
  • Rail preemption
  • Traffic control
  • Transit priority

ASJC Scopus subject areas

  • Software
  • Information Systems
  • Aerospace Engineering
  • Applied Mathematics
  • Control and Systems Engineering
  • Automotive Engineering
  • Computer Science Applications


Dive into the research topics of 'Integrated transit priority and rail/emergency preemption in real-time traffic adaptive signal control'. Together they form a unique fingerprint.

Cite this