Four highway safety groups have asked U.S. safety regulators to require tractor-trailers and big buses to have devices that alert drivers to stopped traffic and brake the trucks if drivers don't respond.

The groups — Advocates for Highway and Auto Safety, the Truck Safety Coalition, the Center for Auto Safety and Road Safe America — petitioned the National Highway Traffic Safety Administration Thursday seeking the requirement for trucks weighing 10,000 pounds or more. They say the systems could prevent more than 2,500 crashes per year, but the agency hasn't required them.

Such systems use radar, cameras and computers to detect objects in front of a vehicle. If the computer determines a crash is imminent, it warns the driver and can even brake vehicles to a stop, preventing a crash. Such devices are becoming common on luxury cars and are making their way into less-expensive automobiles.

The groups contend that from 2003 to 2008 there were 32,000 crashes in which trucks rear-ended other vehicles, killing at least 300 people per year and injuring more than 15,000. They say only 3 percent of the 3 million tractor-trailers on the road now have the technology.

"The safety technology is available to reduce the carnage on America's roads resulting from rear-end crashed by large trucks," Henry Jasny, senior vice president of Advocates for Highway and Auto Safety, said in a statement.

The groups contend the electronic devices could limit truck-car crashes in highway construction zones, where car drivers are stopped and particularly vulnerable. They cited a NHTSA study showing that automatic braking systems would cost $270 to $290 per truck.

The American Trucking Associations, an industry trade group, said it will review data in the petition before taking a position. The association "supports proven safety technologies that prevent crashes and therefore save lives," spokesman Sean McNally said in a statement.

A spokesman for NHTSA said he could not immediately comment on the petition.

Data from 2013 released by NHTSA last year showed the number of U.S. deaths in wrecks involving large trucks — including rear-ended collisions — rose slightly to 3,964, even though the number of traffic deaths nationwide dropped about 3 percent.

Earlier this month, the trucking associations calculated that the truck crash death rate fell 1.6 percent in 2013, to 1.44 deaths per 100 million miles.