Autonomous driving engineers are squarely focused on long-haul freight, the interstate runs with almost no complexity save for a slow curve or an E-ZPass lane. As such, those routes are some of the simpler challenges on the self-driving spectrum.

The biggest hurdle may be infrastructure. The short trip from a factory or distribution center to an interstate is usually far more complicated than the next several hundred miles. The same is true once the machine exits the interstate. One solution is for trucking companies to set up transfer stations at either end, where human drivers handle the tricky first leg of the trip and then hitch their cargo up to robot rigs for the tiresome middle portion. Another station at the exit would flip the freight back to an analog truck for delivery.

Such a system, according to a new study out of the University of Michigan, could replace about 90% of human driving in U.S. long-haul trucking, the equivalent of roughly 500,000 jobs.