Los Angeles: The sun was barely above the horizon on March 13, 2004, but the Slash X saloon bar, in the middle of the Mojave Desert, was already thronging with people.
The bar is on the outskirts of Barstow, a California town between Los Angeles and Las Vegas. It’s a place popular with cowboys and off-roaders, but on that spring day it had drawn the attention of another kind of crowd. A makeshift stadium that had been built was packed with engineers, excited spectators and foolhardy petrol heads who all shared a similar dream: to be the first people on Earth to witness a driverless car win a race.
The race had been organized by the U.S. Defense Advanced Research Projects Agency, or DARPA (nicknamed the Pentagon’s “mad science” division). The agency had been interested in unmanned vehicles for a while, and with good reason: Roadside bombs and targeted attacks on military vehicles were a major cause of death on the battlefield. Earlier that year, DARPA had announced its intention to make one-third of U.S. ground military forces vehicles autonomous by 2015.
Up to that point, progress had been slow and expensive. DARPA had spent around half a billion dollars over two decades funding research at universities and companies in the hope of achieving its ambition. But then came an ingenious idea: Why not create a competition? The agency would invite anyone in the country to design their own driverless car and race them against each other on a long-distance track, with a prize of $1 million for the winner. It would be a quick and cheap way to give DARPA a head start in pursuing its goal.
On the morning of the 132-mile race, a ramshackle lineup of cars gathered at Slash X, along with a few thousand spectators. Things didn’t quite go as planned. One car flipped upside down in the starting area and had to be withdrawn. A self-driving motorbike barely cleared the start line before it rolled onto its side and was declared out of the race. One car hit a concrete wall 50 yards in. Another got tangled in a barbwire fence. The scene around the saloon bar began to look like a robot graveyard.
The top-scoring vehicle, an entry by Carnegie Mellon University, managed an impressive 7 miles before misjudging a hill — at which point the tires started spinning and, without a human to help, carried on spinning until they caught fire. It was over by late morning. A DARPA organizer climbed into a helicopter and flew over to the finish line to inform the waiting journalists that none of the cars would be getting that far.
The race had been oily, dusty, noisy and destructive — and had ended without a winner. All those teams of people had worked for a year on a creation that had lasted, at best, a few minutes.
But the competition was anything but a disaster. The rivalry had led to an explosion of new ideas, and by the next DARPA Grand Challenge in 2005, the technology was vastly improved. An astonishing five driverless cars completed the race without any human intervention.
Now, more than a decade later, it’s widely accepted that the future of transportation is driverless. In late 2017, Philip Hammond, the British Chancellor of the Exchequer, announced the government’s intention to have fully driverless cars — without a safety attendant on board — on British roads by 2021. Daimler, a Germany-based auto manufacturer, has promised driverless cars by 2020, and Ford by 2021. Other manufacturers have made similar forecasts for their driverless vehicles.
On the surface, building a driverless car sounds as if it should be relatively easy. Most humans manage to master the requisite skills to drive. Plus, there are only two possible outputs: speed and direction. It’s a question of how much gas to apply and how much to turn the wheel. How hard can it be?
But, as the first DARPA Grand Challenge demonstrated, building an autonomous vehicle is a lot trickier than it looks. Things quickly get complicated when you’re trying to get an algorithm to control a great big hunk of metal traveling at 60 mph.
For instance, how do you teach a self-driving algorithm to understand that you need to be extra cautious upon hearing the tunes of an ice cream truck, or when passing a group of kids playing with a ball on the sidewalk?
Even harder, how do you teach a car that it should sometimes break the rules of the road? What if an ambulance with its lights on is trying to get past on a narrow street and you need to drive up on the sidewalk to let it through? Or if an oil tanker has jackknifed across a country lane and you need to get out of there by any means possible?
Unfortunately, the answer to that question is probably not anytime soon. That driverless dream we’re all waiting for might be a lot further away than we think. That’s because there’s another layer of difficulty to contend with when trying to build that sci-fi fantasy of a go-anywhere, do-anything, steering-wheel-free driverless car, and it’s one that goes well beyond the technical challenge.