NSF Award
2437781
This EArly-Concept Grant for Exploratory Research (EAGER) project will identify gaps in translating traffic control theoretical research into practical traffic controls (such as traffic signals, ramp meters, and congestion pricing) in real-world settings and will attempt to discover scientific reasons for these gaps. Although academics have developed complex new controls built on models that are supposed to be more accurate, the traffic controls used in practice rely on theories and models that are at least two decades out of date, with no plans to implement the new methods that already exist from research. This issue leads to a fundamental research question: can controls based on more advanced theories perform better than legacy theories in practice? A positive answer will provide a tighter connection between research and practitioners to justify use of new research, and a negative answer will identify causes for performance differences that will inform future research and prepare for next-generation design of transportation and traffic control systems. The societal benefits could include reduced traffic congestion and lower travel times, which improves the well-being of travelers. This project also advances the field by improving the likelihood that traffic control research in general will become useful to practice. Results will be disseminated through conferences, curriculum redesign and development, as well as collaborations with industry and community partners through various educational and outreach activities. <br/><br/>The technical approach to the research is based on studying differences between widely accepted traffic flow models and real traffic from public vehicle trajectory data in the new transportation era. Kinematic wave theory is the most common macroscopic flow model, but how useful is the continuous partial differential equation for describing discrete vehicle traffic? How does heterogeneity in vehicle types and driver behaviors affect model accuracy, which is well-known as the variance in the congested side of the flow-density relationship? How does stochasticity in travel demand and route choices affect controls built for the average value? By modifying traffic flow models to include specific characteristics (such as time- and space-varying flow-density relationships caused by heterogeneous vehicles), researchers will test the importance of such characteristics on predicting reality. What are the important traffic characteristics to consider for different types of traffic controls? Answering this question might validate that specific existing traffic controls are likely effective in practice, or lead to new traffic flow models that incorporate important traffic behaviors.<br/><br/>This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.
