TRB’s National Cooperative Highway Research Program (NCHRP) Synthesis 403 explores the state of practice of adaptive traffic control systems (ATCSs), also known as real-time traffic control systems, which adjust, in real time, signal timings based on traffic conditions, demand, and system capacity. The study methodology included three sequential efforts. The first focused on the selection of ATCSs, which are typically deployed in the United States (and worldwide), and identification of ATCS agencies that could be interviewed. The next effort was to conduct a literature review and gather as much information as possible about ATCS operations and deployments from previous studies. Finally, two electronic surveys were conducted: a shorter e-mail survey for ATCS vendors and a longer web-based survey for ATCS users. Responses were obtained from 34 of 42 agencies in North America, an 81% response rate. Also, responses were obtained from 11 agencies in other countries. Municipal and county traffic operations agencies were the primary contributors among the 45 agencies that responded to the survey. (Author/publisher)
Abstract