You’ll be able to buy a car that can drive itself under most conditions, with an option for override by a human driver, in 2020, according to the median estimate in a survey of 217 attendees of the 2014 Automated Vehicles Symposium. By 2030, the group estimated, you’ll be able to buy a car that is so fully automated it won’t even have the option for a human driver.

Though 2020 is just six years away, there remains a lot of debate over how the industry is going to get there. Most auto manufacturers are incrementalists, adding automated features such as adaptive cruise control, self-parking, and traffic-jam assist, two or three at a time. Google and some others in Silicon Valley, however, are more interested in producing highly or even fully automated cars as soon as possible.

The Society of Automotive Engineers and National Highway Traffic Safety Administration have slightly different definitions of different levels of automated cars. But both basically agree that a “partially automated car” can take over some driving functions such as speed and steering but can’t actually drive itself; “highly automated” can drive itself under most conditions but has a human override, and “fully automated” can drive itself without a human override.

Don Norman, a human-factors engineer from UC San Diego, seemingly endorsed Google’s strategy in a keynote speech Wednesday that argued that even highly automated vehicles might be too dangerous for people to use. “I strongly favor full automation,” he said, but feared that highly automated vehicles might find themselves unable to handle some condition and give the human drive an inadequate amount of time to safely take over.

Airplanes have been highly automated for years, Norman pointed out, but if a plane that is 30,000 feet up suddenly decides it can’t handle current conditions and demands that a human takes over, the human pilot has several minutes before the plane might crash. An auto driver in the same position might have only a fraction of a second.

As I indicated here July 16, another source of debate is whether cars should come with vehicle-to-vehicle (V2) communications. This would allow, among other things, cars to operate in “platoons” of several to many cars each. Since the cars would be in constant contact with each other, they could close the gaps between them and greatly increase highway capacities.

On the other hand, cars using adaptive cruise control today are typically programed to operate 2 to 4 seconds behind the vehicles in front of them. Greek auto engineer Markos Papageorgiou pointed out that a 2-second headway means 1,800 vehicles an hour, which is less than the 2,200-vehicle-per-hour capacity that has been frequently measured for freeway lanes. “Traffic conditions will worsen without cooperative traffic management,” meaning V2V, says Papageorgiou.

However, the fact that manufacturers have set their current equipment for 2-second headways doesn’t mean that’s the best they can do. Google isn’t interested in platooning and seems to think that it will be able have its cars safely operate in close quarters with other cars without V2V communications.

Another question was how long it would take before autonomous cars outnumber human-driven ones on the highways. Pessimists doubted the 2020 date for highly automated and 2030 for fully automated, but even if the first highly automated cars go on sale in 2020, most cars sold that year won’t be highly automated.

Cruise control and antilock brakes were first introduced on American cars in the early 1970s, yet it was probably twenty years before most cars sold had these features and at least another decade before nearly all new cars had them. Based on this, some experts think that self-driving cars may not dominate the highways until 2060 or later.

On the other hand, partially automated cars being sold today can probably be retrofitted into highly automated cars with the addition of a few sensors and a software upgrade. Once fully automated cars enter the market in 2030, virtually all highly automated cars could probably be turned into fully automated cars with nothing more than a software upgrade. Such retrofitting possibilities could rapidly hasten the adoption of self-driving cars.

Though most people agreed that autonomous cars would have dramatic social effects, few could predict what they would be. “For many things, we don’t even know the signs much less the magnitude,” said one transportation expert, meaning we don’t know whether autonomous cars would increase or reduce miles of driving, auto ownership, energy consumption, or a variety of other factors.

Most people agreed that autonomous cars combined with Uber-like smart-phone apps would increase car sharing. But this wouldn’t necessarily decrease car sales, though it might decrease the size of the average car sold.

“Most people buy cars that are as big as they sometimes need, even if they don’t need a car that big all the time, which is why so many F-150s are sold,” said Brad Templeton, who has been thinking about what he calls robocars for longer than most. “If people can use an app to summon a large car on the few times they need one, they’ll buy a smaller car for their daily use,” he suggested.

Templeton also made a point for urban planners: “The Internet succeeded because the people who built it use a stupid infrastructure, rather than trying to design intelligence into it. The stupid infrastructure was easily adapted into all kinds of uses. Urban planners need to realize that because they don’t know what the future will be, they need to provide stupid urban infrastructure, for example, bus-rapid transit instead of light rail because bus lanes can easily be used for something else if large buses turn out to be unnecessary.”

I may be guilty of wishful thinking, but I’m inclined to believe that highly automated cars will become dominant sooner rather than later. In 1912, the year before Henry Ford introduced the moving assembly line to build Model Ts, less than 5 percent of American households owned a car. By 2027 1927, more than half did. The advantages of autonomous cars are so great that I suspect their adoption will be nearly as fast.

Originally published on The Antiplanner blog. Published on KurzweilAI with permission.

Which of the major automotive manufacturers will be first to offer a fully autonomous (self-driving) car to consumers in the U.S.?

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