April 2013

Enhanced SMART Signal system provides real-time traffic data to road users and traffic engineers

When traffic signals run efficiently, local road networks become faster and safer. With increasing congestion on our nation’s roadways, transportation engineers are looking for new ways to monitor and manage local traffic signal systems. Despite this growing need for traffic signal data and analysis, most existing signal control systems don’t make it convenient to monitor or archive traffic signal performance data. That’s where SMART Signal (Systematic Monitoring of Arterial Road and Traffic Signals) technology developed by University of Minnesota researchers comes in.

“In past research, we developed the SMART Signal technology to collect and analyze real-time traffic signal and signal system performance data and deployed that technology in several test projects,” says lead researcher Henry Liu. “In this most recent project, we’ve enhanced SMART Signal with plug-and-play technology that makes it extremely simple and much more cost-effective to deploy.”

The enhanced SMART Signal system connects
quickly to traffic signal controller cabinets with just
a power source and an Ethernet connection.

The enhanced SMART Signal system features a single data collection unit that connects quickly to standard traffic signal controller cabinets. “The ultimate goal is to reduce the effort of customized installation as much as possible,” says Liu.

Funded by MnDOT, the latest SMART Signal research has also put real-time traffic data from one of the test projects—Minnesota’s Trunk Highway 13 in Burnsville and Eagan—live on the web, where both road users and traffic engineers can access it quickly and easily. Drivers can now use the new web interface to view real-time travel information, historical queue length, and real-time queue length at intersections equipped with the system. In addition, users can calculate actual travel time along the roadway between any two intersections, at any time of day.

Researchers expect that this innovative traffic signal technology will provide even greater benefits in the future. Researchers plan to use data from SMART Signal to develop an intersection safety monitoring system that will determine if a signal is properly timed to maximize safety, particularly under different weather conditions. Better signal timing could mean less red-light running, resulting in fewer crashes. The system could also be used to measure the frequency of red-light running and calculate the probability of related crashes.