Changing the Way Highways Operate
It is not news that congestion has reached epic proportions. According to The 2007 Urban Mobility Report published by the Texas Transportation Institute, "Congestion caused urban Americans to travel 4.2 billion hours more and to purchase an extra 2.9 billion gallons of fuel for a congestion cost of $78 billion." This growing traffic leads to costly delays that undermine the American quality of life, jeopardize the economic system, waste fuel, and contribute to pollution. The available highway capacity simply is not keeping pace with traffic demand. In addition to adding capacity, another solution is to optimize the operation of the existing system.
In 2007, the U.S. Department of Transportation (USDOT) challenged the transportation community to find revolutionary solutions to traffic congestion across the country. One such effort started in August 2007 when USDOT announced the selection of five cities to become Urban Partners with the Agency to tackle congestion. Through Urban Partnership Agreements, USDOT and its partner cities will use an unprecedented, four-pronged approach that includes tolling, transit, technology, and telecommuting. With new technology as the key enabler, the four parts will work together to spread the traffic load more evenly across the transportation system.
At the Federal Highway Administration's (FHWA) Turner-Fairbank Highway Research Center, several research projects concentrate on developing a range of new methods and technical innovations to reduce congestion. Smart sensors and traffic signals should be able to sense traffic, adapt to it, and keep it moving to help reduce delays. Adaptive signal controls using new, low-cost, ACS Lite software already help move vehicles faster. Technologies such as global positioning systems, geographic information systems, more powerful cell phones, and even new higher powered dedicated communication systems may one day be able to help improve communications between cars and the roadside. Technologies like these already have facilitated electronic toll collection, reducing delays at toll plazas. The evolution of these communications technologies will enable in-vehicle navigation systems to identify not only what street a vehicle is on but also the specific lane on which it is located.
FHWA's Office of Operations R&D is using modeling and simulations to determine the trajectory of an oncoming vehicle and whether it will end in a crash, gauge whether a vehicle will run a red light, and determine if it is safe for a vehicle to make a left turn at a red light. Advanced research will develop and evaluate concepts for innovative vehicle-highway automation, new methods for data acquisition, and new ways to improve the operation of traffic signal systems.
This issue of Public Roads features an article titled "A New Look at Sensors," which describes some of the latest and most effective strategies to sense the characteristics of vehicles. They enable advanced adaptive control and ramp metering systems to accommodate the impacts of varying, and often increasing, traffic flow and incidents, and thus reduce congestion and minimize travel time variability.
Research solutions have contributed to the success of the transportation system. Infrastructure research provides new ways to build roads that last longer. Safety research makes roads less dangerous and crashes more survivable. The ultimate goals of applied research and long-term, exploratory advanced research in the operations area are to one day eliminate traffic congestion and crashes altogether.
Joseph I. Peters
FHWA Office of Operations R&D