October 1, 2008 Engineers and computer scientists developed software to coordinate the movement of thousands of cars in case of an emergency evacuation. The tool analyzes traffic flow to create an adaptable model and adjust routing in real time.
In most American cities, gridlock is a fact of life -- but don't blame it all on that daily commute. Sometimes, it's the unexpected. Natural disasters and other emergencies can create huge traffic jams. In fact, hurricanes Katrina and Gustav both forced 2 million people out of their homes. Now, scientists and engineers may have a solution to evacuation chaos.
For Angela Tyson and other drivers, detours mean headaches. "Sometimes I wanna cry because I'm stuck in traffic so long!" Tyson told Ivanhoe.
With road construction, detours usually come with some advance warning; but how do you plan for the unexpected? The massive Minneapolis bridge collapse was one of the first tests for a new kind of computer software. It's a rapid response emergency planning tool designed to help traffic engineers reroute thousands -- even millions -- of drivers quickly, whether it's a bridge disaster or a statewide hurricane evacuation.
"This model allows us to accommodate such a vast amount of traffic over a short period of time, over such a large geographical area," Yi-Chang Chiu, Ph.D., a civil engineer at the University of Arizona in Tucson, Ariz., told Ivanhoe.
Civil engineers at the University of Arizona developed the tool, which analyzes traffic flow to create a model based on drivers' behavior.
"Basically, with this model, you are able to estimate -- under any circumstances -- how they choose when to leave their destination -- which route they take," Dr. Chiu said.
Using this software, transportation managers can respond and adapt as emergencies unfold. They can even plan for potential traffic nightmares before they happen -- like evacuating a packed football stadium in an emergency.
BACKGROUND: Planning for a natural disaster necessarily includes a plan for moving people out of that disaster area, whether in anticipation of a weather disaster that can be forecast ahead of time like a hurricane, or in response to something like an earthquake. In the latter case, decisions need to be made quickly, which is the scenario on which Dr. Chiu's research focuses. His software can react to situations in real time, and is based on real traffic data showing how drivers navigate obstacles and delays. The model considers variables such as when drivers are likely to take to the roads and the likelihood that they will be listening to news updates on the radio. It can even be combined with airborne hazard models to show how drivers would respond to a plume of dangerous gases
TRAFFIC FLOW: Scientists studying traffic's ebb and flow create complex mathematical models in order to simulate the actual patterns that emerge on roads. These models are an important part of efforts to improve the placement or timing of various items like traffic lights, additional lanes, and more. The scientists use insights developed from sources as diverse as the physics of fluid flow and human reaction time in order to build better models and glean insights from them.
The American Society of Civil Engineers, the Human Factors and Ergonomics Society, and the Institute for Operations Research and the Management Sciences contributed to the information contained in the TV portion of this report.