Driving on Interstate 495 toward Boston in a Ford Fusion one chilly afternoon in March, I did something that would’ve made even my laid-back long-ago driving instructor spit his coffee over the dashboard: I took my hands off the steering wheel, lifted my foot off the gas pedal, and waited to see what would happen. The answer: not much. To a degree, the car was already driving itself. Sensors were busy tracking other vehicles and road markings; computer systems were operating the accelerator, the brake, and even the steering wheel. The car reduced its speed to keep a safe distance from the vehicle ahead, but as that car sped up again, mine did so too. I tried nudging the steering wheel so that we drifted toward the dotted line on my left. As the line approached, the car pushed the steering wheel in the opposite direction very slightly to keep within its lane.
The technology behind this kind of vehicle automation is being developed at a blistering pace, and it should make driving safer, more fuel-efficient, and less tiring. But despite such progress and the attention surrounding Google’s “self-driving” cars, full autonomy remains a distant destination. A truly autonomous car, one capable of dealing with any real-world situation, would require much smarter artificial intelligence than Google or anyone else has developed. The problem is that until the moment our cars can completely take over, we will need automotive technologies to strike a tricky balance: they will have to extend our abilities without doing too much for the driver.