The European Union is funding research on a project called SARTRE. SARTRE is the first real-world test of a "road train". The idea involves a convey of cars autonomously following a human-operated lead vehicle (a tractor-trailer) driven by a professional.
Think driving from Dallas to Denver and you are one of four cars following your "leader" - - by reducing wind resistance and traveling at a steady speed, your convoy could improve fuel economy and reduce tailpipe emissions by 20%. Your 12-hour car trip could become cheaper, more sustainable, safer, and pleasant - - you might be able to enjoy that new book during the trip.
The convoy key is the ability to communicate with and react to one another - - part camera, part radar/lidar senors, part Wi-Fi - - and all software.
Check out the test video