For artificial intelligence, human nature is the unknown quantity.
Three years ago, Google’s self-driving car project abruptly shifted from designing a vehicle that would drive autonomously most of the time while occasionally requiring human oversight, to a slow-speed robot without a brake pedal, accelerator or steering wheel. In other words, human driving was no longer permitted.
The company made the decision after giving self-driving cars to Google employees for their work commutes in San Francisco and recording what the passengers did while the autonomous system did the driving. In-car cameras recorded employees climbing into the back seat, climbing out of an open car window, and even smooching while the car was in motion, according to two former Google engineers.
“We saw stuff that made us a little nervous,” Chris Urmson, a roboticist who was then head of the project, said at the time. He later mentioned in a blog post that the company had spotted a number of “silly” actions, including the driver turning around while the car was moving.
Johnny Luu, a spokesman for Google’s self-driving car effort, now called Waymo, disputes the account, but says behavior like an employee rummaging in the back seat for his laptop while the car was moving and other “egregious” acts contributed to shutting down the experiment.
We humans are easily distracted by our games, phones and mates. And automotive engineers, computer interaction designers and, yes, lawyers, wonder if the self-driving cars they are working on will ever really be able to count on us in an emergency.
Engineers say they believe that cars will be intelligent enough to do all the driving, somewhere between five years and a decade from now, depending on whom you ask.
But until then, what passes for autonomous driving will be a delicate ballet between human and machine: Humans may be required to take the wheel at a moment’s notice when the computer can’t decide what to do.
To outline a development path to complete autonomy, the automotive industry has established five levels of human-to-machine control, ranging from manual driving — Level 0 — up through complete autonomy, Level 5. In the middle, Level 3 is an approach in which the artificial intelligence driving the car may ask humans to take over in an emergency.
But many automotive technologists are skeptical that the so-called handoff from machine to human can be counted on, because of the challenge of quickly bringing a distracted human back into control of a rapidly moving vehicle.
“Do you really want last-minute handoffs?” says Stefan Heck, chief executive of Nauto, a startup based in Palo Alto, California, that has developed a system that simultaneously observes both the driver and the outside environment and provides alerts and safety information. “There is a really good debate going on over whether it will be possible to solve the handoff problem.”
Nauto’s data shows that a “driver distraction event” occurs, on average, every four miles. Heck says there was evidence that the inattention of human drivers was a factor in half of the approximately 40,000 traffic fatalities in the United States last year.
Last month, a group of scientists at Stanford University presented research showing that most drivers required more than five seconds to regain control of a car when — while playing a game on a smartphone — they were abruptly required to return their attention to driving.
The handoff challenge is compounded by what is known as “over-trust” by automotive engineers.
Over-trust was what Google observed when it saw its engineers not paying attention during commutes with prototype self-driving cars.
Driver inattention was implied in a recent National Highway Traffic Safety Administration investigation that absolved the Tesla from blame in a 2016 Florida accident in which a Model S sedan drove under a tractor-trailer rig, killing the driver.
Solving the over-trust issue is a key to autonomous vehicles in the Level 3 category, where the computer hands off to humans.
The first commercial vehicle to offer Level 3 autonomy is expected to be released next month by Audi.
A version of its luxury A8 model will be able to drive in stop-and-go freeway traffic up to 37 mph while allowing drivers to pursue other tasks.
The vehicle reportedly will notify drivers in emergencies, giving them 8 to 10 seconds to intervene.
Despite these limited advances, many automotive technologists remain uncertain about whether technology will ever be able to operate smoothly with a human driver who may be reading email or playing World of Warcraft.
“I believe that Level 3 autonomous driving is unsolvable,” says John Leonard, a mechanical engineering professor at the Massachusetts Institute of Technology who has collected detailed examples of driving situations that are currently impossible for state-of-the-art autonomous driving systems. “The notion that a human can be a reliable backup is a fallacy.”