Smart City

The concept of Smart City is gaining popular attention with the goal of sustainability and efficiency, the needs of enhancing quality and performance, and the explosion of technological advances in communication and computation. Given that 50% of the world’s population lives in urban regions, critical infrastructures of energy, transportation, and health and their growing interdependencies have to be collectively analyzed and designed to provide the substrate for the realization of the Smart City Concept. The active-adaptive control laboratory is addressing one of these infrastructures, Urban Mobility, and in particular the concept of dynamic toll pricing to alleviate congestion.

Real-time Control of Traffic Flow Using Dynamic Toll Pricing

Thao Phan, Anuradha Annaswamy, Diana Yanakiev, and Eric Tseng

With the growth and expansion of many large metropolitan centers in the last few decades, the problem of traffic congestion continues to grow and vex commuters, commercial drivers, city planners and officials, and environmentalists worldwide. Over 1 billion vehicles travel on the roads today, and that number is projected to double by 2020. Driving a car is an unavoidable choice for at least 65% of city populations, who rely on their vehicles to get to school or to work. An on-going project in our laboratory, funded by Ford, explores the use of dynamic toll pricing for alleviating traffic congestion, and increasing traffic flow during peak hours of the day. A model-based approach to dynamic toll pricing has been developed to provide a systematic method for determining optimal freeway pricing schemes. Real-time traffic information from on-road sensors is integrated with complex models of driver behavior and traffic flow to determine the toll price, which acts as a controller to divert traffic flows to desired lanes and routes and lessen the traffic congestion experienced in certain areas. The three key findings from this study are [1,2]:

  1. With careful design of the pricing scheme, that includes important linear and nonlinear components, our dynamic toll pricing system has the ability to both prevent and exit quickly from traffic congestion.
  2. Not only does our method improve speeds from dynamic toll lane customers, but it also improves overall traffic flow of the freeway.
  3. This approach has the ability to be easily modified for different objectives in controlling the traffic flow.

  • [1] Thao Phan, Anuradha Annaswamy, Diana Yanakiev, and Eric Tseng, “Real-time Control of Traffic Flow Using Dynamic Toll Pricing,” (to be submitted to) American Control Conference, Boston, MA. July 2016.
  • [2] Thao Phan, “Dynamic Toll Pricing for Alleviation of Traffic Congestion in Highways,” MS Thesis, Department of Mechanical Engineering, August 2015.