Improving Intersection Safety and Operations Using Advance Warning of End of Green System (AWEGS)
Author(s):
S.R. Sunkari, H.A. Charara, R.T. Parker, T.A. Palekar
Publication Date:
January 2007
Abstract:
This project summary report summarizes the research performed in Texas Department of Transportation (TxDOT) Project 0-5113. The advance warning of end-of-green system (AWEGS) provides warning to motorists on high-speed approaches to isolated traffic signals about the onset of yellow by using flashing beacons on a "BE PREPARED TO STOP WHEN FLASHING" sign. AWEGS enhances the dilemma zone protection at intersections having conventional dilemma zone detectors by protecting vehicles traveling over the 85th percentile speeds up to the 99th percentile speeds. The objective of this two-year project was to improve the AWEGS algorithm, deploy the improved algorithm at existing AWEGS deployments, and install AWEGS at a new location. Researchers identified the following improvements to be made to AWEGS: reduce false actuations, improve truck detection and treatment, design and evaluate overhead sign configuration, develop failsafe operations due to detector failure, provide warning about the presence of queues, and improve AWEGS interface. Researchers modified the algorithm to ensure that AWEGS would operate safely when either of the advance detectors fails and made numerous other improvements. The AWEGS technology was installed in two locations, one in Waco and one in Brenham. Both locations showed a reduction in red-light running of approximately 40 percent. AWEGS was also installed in College Station and has shown a 40 percent reduction in red-light running on one approach and about 60 percent reduction on the other approach.
Report Number:
0-5113-S
Electronic Link(s):
Document/Product
http://library.ctr.utexas.edu/hostedpdfs/txdot/psr/5113.pdf
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