The researchers ran a simulation of their approach in the city center of Dresden. The area has 13 traffic light–controlled intersections, 68 pedestrian crossings, a train station that serves more than 13,000 passengers on an average day and seven bus and tram lines that cross the network every 10 minutes in opposite directions. The flexible self-control approach reduced time stuck waiting in traffic by 56 percent for trams and buses, 9 percent for cars and trucks, and 36 percent for pedestrians crossing intersections. Dresden is now close to implementing the new system, says Helbing, and Zurich is also considering the approach.
Traffic jams aren’t just infuriating, they cost time and money, says Orosz. Estimates suggest that in one year, the U.S. driving population spends a cumulative 500,000 years in traffic at a cost of about $100 billion. And the roads are just going to get more congested. The optimal way of dealing with such congestion is to take an approach like Helbing’s and combine it with technologies that deal with driver behavior, Orosz says. Car sensors that detect the distance between your bumper and the car in front of you can prevent a sweep of brake-slamming that can tie up traffic, for example.
“In general these algorithms improve traffic, but maybe not as much as they do on paper because we are still human,” he says. “It is still humans driving the cars.”