Several luxury automakers now have systems that automatically steer cars on highways

With automakers starting to make realistic predictions about when they can deliver self-driving cars, many motorists may not realize that to a large extent, such cars are here already.
Infiniti, Mercedes-Benz, Lexus and Acura are among automakers that have started fielding vehicles that allow drivers to take their hands off the wheel. The cars stay on the road using a combination of radar and camera systems that track lane lines on the pavement. Most have alarms that remind drivers to put their hands back on after a few seconds. But not all: Infiniti’s Q50 sedan can steer itself for miles without a finger on the wheel.
See video of CMU autonomous vehicle.