Efforts to shut out human drivers notwithstanding, stepwise automation of various features offers a more realistic short-term view of how the shift to driverless cars will play out, according to Ragunathan “Raj” Rajkumar, a professor of electrical and computer engineering in Carnegie Mellon University’s CyLab and veteran of the university’s efforts to develop autonomous vehicles, including the Boss SUV that won the DARPA 2007 Urban Challenge. “The transition to roadways filled with driverless drones will be gradual,” he says. “People will buy cars with more and more autonomous features in the coming years until, sometime in the 2020s, the majority of vehicles on the road will for the most part be fully autonomous.”