Advanced science.  Applied technology.


SwRI models traffic behavior associated with mass evacuation of urban areas

January 25, 2010 — Urban roads can be overwhelmed during disaster evacuations, such as during Hurricane Katrina. As smartphone technology advances and proliferates, Southwest Research Institute® (SwRI®) is developing and applying agent-based modeling techniques to study how providing evacuation route information via smartphone affects urban traffic congestion.

Agent-based models simulate the actions and interactions of autonomous agents, such as individual vehicles, to better understand how their actions affect an overall system, such as roadway traffic. Combining elements of game theory, complex systems, emergence, computational sociology, multi-agent systems and evolutionary programming, the SwRI model uses Monte Carlo methods to introduce randomness. By modeling the simultaneous operations and interactions of multiple agents, SwRI engineers are seeking to better understand, re-create and predict complex phenomena, specifically how personalized mapping can facilitate mass evacuations of urban areas.

"As the number of vehicles crowding existing highway infrastructure increases, the effects of congestion range from minor irritation and loss of productivity to increased fuel use and pollution," says Paul Avery, a senior research engineer in the SwRI Intelligent Vehicle Systems Section. "In the case of a disaster evacuation, road systems can become so overburdened that the risk of injury and death greatly increases."

With more than 20 years of experience in intelligent traffic systems research and development, SwRI created an agent-based traffic system model based on the San Antonio highway system, where individual vehicles, created as separate agents, interact with other vehicles. The simulations look at traffic congestion under extreme conditions, such as when a mass evacuation is under way, and how that is affected when a small percentage of vehicles are provided with a personalized evacuation route via smartphone.

"Our simulations indicate that when targeted information about traffic conditions is provided through a smartphone app, driver behavior can be modified to improve the overall traffic flow and help decrease congestion," says Ryan Lamm, IVS manager at SwRI. "This application is a new approach for using an emerging technology to increase driver mobility and safety within the existing infrastructure."

For more information contact Deb Schmid at (210) 522-2254, Communications Department, Southwest Research Institute, 6220 Culebra Road, San Antonio, TX 78238-5166.