In a few weeks, about 2,800 cars, trucks, and buses will start talking to one another on the streets of Ann Arbor, Mich., in a giant experiment that government officials are hoping will lead to safer roads.
Wireless devices will allow the vehicles to send signals to one another, warning their drivers of potential dangers such as stopped traffic or cars that might be blowing through red lights. They can even get traffic lights to turn green if no cars are coming the other way.
The U.S. Department of Transportation and the University of Michigan are hoping the yearlong, $25 million project generates data that show the devices can cut down on traffic crashes. Eventually, officials say, that could lead to the devices going in every car.


