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Employing Cyber-Physical Systems: Dynamic Traffic Light Control at Road Intersections



Ossama M. Younis, Nader Moayeri


Traffic Lights are used to control traffic at road intersections. Typically, the employed traffic light control mechanism on the road operates according to a periodic schedule to change the light/color (red/yellow/green). In some places, a different schedule is employed at late night/early morning hours. Such fixed light control mechanism does not adequately account for changing traffic conditions, and is unaware of/unresponsive to congestion. In this work, we propose a novel framework for dynamic traffic light control at road intersections. The framework relies on a simple sensor network to collect traffic data and includes novel protocols for traffic flow control to handle congestion and facilitate more efficient flow. We show that our proposed algorithms have low overhead and are practical to employ in live traffic flow scenarios. Through analysis and extensive simulations, we demonstrate the benefits of our framework in optimizing traffic flow metrics, such as traffic throughput, average vehicle waiting time, and vehicle waiting line length. This work is a step toward developing/employing smart traffic lights, which are part of the envisioned smart city.


Traffic light control, traffic flow optimization, distributed algorithms, sensor networks


Younis, O. and Moayeri, N. (2017), Employing Cyber-Physical Systems: Dynamic Traffic Light Control at Road Intersections, Elsevier, [online], (Accessed July 19, 2024)


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Created December 1, 2017, Updated January 27, 2020