Most of the rural or suburban high-speed isolated intersections have higher traffic volumes on the major
approach compared to the minor approach. The vehicle platoons on major approach are often forced to
stop frequently due to conflicting calls placed by few vehicles on the minor approach. To overcome this
issue, platoon-priority signal control systems have been developed to progress platoons efficiently at
these intersections in a number of previous studies. In addition, Advance Warning Flashers (AWF) are
used at these intersections to provide advance warning of end of green to the motorists. The conventional
method uses trailing overlap green which holds the green for a fixed time after gap-out. This trailing
overlap green replaces the existing dilemma-zone protection provided by loop detectors and also
increases delay on the minor approach. Recently, Advance Warning of End of Green System (AWEGS)
has been developed to provide advance warning at these intersections without having to hold green after
gap-out. The purpose of this research study is to develop and evaluate the benefits of an integrated system
which provides platoon-priority, advance warning of end-of-green, and also dilemma-zone protection at
the end-of-green for rural high-speed isolated intersections. Cabinet-in the-loop tests were performed
using a real world scenario. These study results showed 50 percent reduction in delay and stops on the
major approach with platoons. It was found that the total intersection delay and stops were reduced by as
much as 20 percent. The system was also successful in providing advance warning to the motorists by
predicting gap-outs 7 to 8 seconds earlier in the majority of the cases.
Liu, Henry; Bhimireddy, Sundeep.
Development of a Platoon-Priority Control Strategy with/out Smart Advance Warning Flashers for Isolated Intersections with High-Speed Approaches.
Minnesota Department of Transportation.
Retrieved from the University of Minnesota Digital Conservancy,
Content distributed via the University of Minnesota's Digital Conservancy may be subject to additional license and use restrictions applied by the depositor.