Enhancements to the Advance Warning of End of Green System (AWEGS)

The objective of this project was to make improvements to the Advance Warning of End of Green System (AWEGS). These improvements have enhanced the operation of AWEGS as well as have made the implementation of AWEGS much simpler. The enhancements include reducing false actuations, accounting for detector failures, detecting and treating queues, improving the visibility of the AWEGS sign, and making numerous modifications to the AWEGS interface. The improvements to AWEGS have made a significant improvement in the implementation of AWEGS at new locations. These improvements were implemented at existing AWEGS sites and at a new location in College Station, Texas. However, the advance warning at the College Station location is higher than expected at times. This basically means that sometimes the controller is not gapping out after AWEGS predicted that it would. Analysis of the data has shown that this is primarily due to the high volumes on the arterial approaches at the College Station site. These results have illustrated that the volumes have an impact on the operation of AWEGS and should be considered in the selection of future AWEGS sites. From the data collected from all AWEGS locations, it appears that AWEGS would function very well when the average daily traffic (ADT) at the intersection is below 15,000 vehicles. Above those volumes, the advance warning times can be higher than expected. A higher advance warning is not harmful. However, if it happens frequently, it can give rise to some confusion in the motorists.