The recommendations help to encourage the auto industry to adopt additional safety features, Transportation Secretary Anthony Foxx said Thursday in announcing them to a group of automotive engineers in Washington, D.C. Foxx’s department includes the traffic safety agency. Devices that use cameras and radar to track traffic and objects in front of a driver could go a long way toward cutting the number of crashes. Nearly a third of all crashes reported to police in the U.S. in 2013 were rear-end collisions with other vehicles, according to NHTSA.