The overarching goal of this research project was to investigate the potential for the NCDOT Central Office Signal Timing (COST) Section to monitor and assess the quality of field deployed closed-loop signal system plans using the data inherent in the systems. The project is complete and has produced recommendations and deliverables that should enhance the COST Section’s ability to achieve its mission of developing and maintaining quality signal coordination plans across the state of North Carolina.
Key findings and conclusions include the identification of a series of monitoring and analysis elements that can be implemented using the OASIS software detector and split monitor logs. In order to analyze dynamic, cycle-by-cycle bandwidth, a tool entitled the Dynamic Bandwidth Analysis Tool (DBAT) was developed and provided as a project deliverable. The DBAT tool was enhanced to provide exhaustive search optimization that identifies offset combinations that maximize dynamic bandwidth for a given set of split monitor log cycle-by-cycle signal indications. DBAT optimization is feasible for systems up to four or five intersections in length. An LP formulation was developed and tested that overcomes the system size limitation. The LP formulation can serve as the basis for future development of an implementable dynamic bandwidth optimization tool.