In a few weeks, about 2800 cars, trucks and buses will start communicating with each other on the streets of Ann Arbor, Michigan, in a giant experiment that US government officials are hoping will lead to safer roads.Wireless devices will allow vehicles to send signals to each other, warning drivers of potential dangers such as stopped traffic or cars going through red lights. Something everyone will enjoy is the ability for cars to change traffic lights to turn green if no cars are coming the other way.COULD GO INTO EVERY CARThe US Department of Transportation and the University of Michigan are hoping the year-long project generates data which shows the devices can cut down on traffic crashes. Officials say eventually this could lead to the devices going in every car. There are about 500 vehicles with the devices currently on the roads. That will rise to 2800 in about six weeks, officials said on Tuesday, August 21, 2012. Transportation secretary Ray LaHood said: "This is a big day for safety. We'll use this information to decide if vehicle technology can be applied to daily lives."More than 32 000 people died in 2011 in US traffic crashes, down 1.7% from 2010. The number of crashes has fallen in recent years as car manufacturers added safety devices such as air bags, antilock brakes and stability control, which help drivers maintain control in emergency situations.LaHood said 80% of crashes in which the drivers aren't impaired by drugs or alcohol could be prevented — or the severity reduced — if cars could "talk" to each other.It is not clear when the technology will be implemented in vehicles around the country as LaHood suggests they first need to analyse the data received from the experiment before it is decided. He claims a decision will be made in 2012.