Development of a Queue Warning System Utilizing ATM Infrastructure: System Development and Field Testing

Principal Investigator:

John Hourdos, Director, MN Traffic Observatory, Civil, Environmental and Geo-Engineering


  • Henry Liu, Associate Professor, Civil, Environmental and Geo-Engineering

Project Summary:

MnDOT has been a leader in adopting new technologies to help reduce congestion and improve safety. For example, MnDOT has already deployed an extensive infrastructure for Active Traffic Management (ATM) on I-35W and I-94 with plans to expand on other segments of the Twin Cities freeway network. The ATM system includes intelligent lane control signals (ILCS) spaced every half mile over every lane to warn motorists of incidents or hazards on the roadway ahead. Variable Advisory Speed Limits are also used to warn motorists of congestion downstream on the mainline. This project aims to develop a system that can identify lane-specific stop-and-go or queuing conditions on the freeway and uses existing ILCS to warn motorists upstream for rear-end collision prevention. We plan to deploy and field test our system at two locations in the ATM equipped network that have a high frequency of rear-end collisions. These locations experience significantly different traffic flow conditions allowing for the development of a robust system that can be deployed in other locations that experience similar problems. The I-94 WB segment in downtown Minneapolis is known for its high crash rate due to rapidly evolving shockwaves while the I-35W segment north of the TH-62 interchange experiences long standing queues extending into the freeway mainline.


Project Details:

  • Start date: 05/2014
  • Project Status: Completed
  • Research Area: Transportation Safety and Traffic Flow