Aleksandar Stevanovic, PhD, P.E., FASCE

Associate Professor

Director, Pittsburgh Intelligent Transportation Systems (PITTS) Lab

218D Benedum Hall | 3700 O’Hara Street | Pittsburgh, PA 15261 P: 412-383-3766

stevanovic@pitt.edu www.pittslab.pitt.edu

Traffic Signal Control for Greener Environment

Our traffic signals have been traditionally timed to reduce congestion and improve commuting times for traffic with predominantly private cars. As a society, we have not paid enough attention to retime traffic signals to decrease unnecessary fuel consumption and vehicular emissions. Extra fuel consumption does not only reflect energy inefficiency, but it generates extra emissions some of which could be harmful for human health (e.g., particulate matters) whereas others (e.g., CO2) can contribute to the climate change. Our recent research on this subject has revealed that correlation between signal operations and fuel consumption (as the main drive of vehicular emissions) is of complex nature. Any attempt to minimize excess fuel consumption, due to traffic signals, requires a sophisticated approach to find the right balance of signal timings taking in consideration a half of a dozen of factors representing various operational and traffic conditions. This line of research is currently supported by three sponsors: Pitt’s Mascaro Center for Sustainable Innovation, Lake County (IL) department of Transportation, and US Department of Energy (through a contract with the University of Tennessee – Chattanooga).

Flexible Utilization of Roadways for Traffic Management in Connected and Automated Vehicle Environment

With ever-increasing traffic demand our urban road infrastructure will soon reach a state of constant oversaturation where it will be difficult to distinguish between peak and non-peak traffic periods, all accompanied with long and unreliable travel times. At the same time, our technological advances in IT and Connected and Automated Vehicles (CAVs) have opened some opportunities for innovative traffic management concepts. We developed such a concept, whose first version we named Combined AlternateDirection Lane Assignment and Reservation-based Intersection Control (CADLARIC). In CADLARIC, vehicles can utilize any available lane, even the ones who have been traditionally reserved for the other direction. In such traffic control scheme CAVs preposition themselves in a proper lane ahead of the downstream intersection, an action which enables traffic control logic to better resolve vehicular conflicts within the intersection boundaries. The proposed concept, through its numerous variations, has shown very promising results both in hypothetical and field-like networks. In such heavy-automated control environment vehicles constantly communicate (among themselves and with smart road infrastructure) to efficiently utilize any available road space. In this way they are able to reduce number of conflicts at intersections and improve travel times on urban arterials. This line of research is currently not funded but it is heavily utilized in a variety of proposals to NSF, DOE, FHWA, and similar sponsoring agencies.