Evaluating Different Methods for Estimating Queue Length on Access Ramps

Ramp metering is a traffic management strategy designed to mitigate congestion on freeways by adjusting the flow of traffic entering freeways. Ramps are often metered individually, where the ramp exit rate can be adjusted based on mainline congestion. Coordinated ramp metering is a higher-level strategy, where the exit rates across several adjacent ramps can be coordinated to reduce or eliminate mainline bottlenecks. In both individual or coordinated ramp metering systems, efficiency is gained when timely and accurate information about the ramp queue state is available. Currently, this information is collected using loop detectors, which exhibit limited accuracy in highly-congested (i.e., bumper-to-bumper) conditions. To this end, this project will develop a computer-vision-based method to infer queue states along the freeway ramps. The proposed method will be validated through comparisons against the loop detectors.


  • English


  • Status: Completed
  • Funding: $108000
  • Contract Numbers:


  • Sponsor Organizations:

    Office of the Assistant Secretary for Research and Technology

    University Transportation Centers Program
    Department of Transportation
    Washington, DC  United States  20590
  • Managing Organizations:

    Mountain-Plains Consortium

    North Dakota State University
    Fargo, ND  United States  58108
  • Project Managers:

    Tolliver, Denver

  • Performing Organizations:

    Dept. of Civil and Environmental Engineering

    University of Utah
    Salt Lake City, UT  United States 
  • Principal Investigators:

    Markovic, Nikola

    Rashidi, Abbas

  • Start Date: 20221013
  • Expected Completion Date: 20240731
  • Actual Completion Date: 20231218
  • USDOT Program: University Transportation Centers Program
  • Source Data: MPC-699

Subject/Index Terms

Filing Info

  • Accession Number: 01863394
  • Record Type: Research project
  • Source Agency: Mountain-Plains Consortium
  • Contract Numbers: 69A3551747108
  • Files: UTC, RIP
  • Created Date: Nov 8 2022 5:28PM