Google's landmark deployment of autonomous cars — vehicles that can drive themselves — onto public roads and into live human traffic last summer and early fall was announced casually, and after the fact.

Astonishingly, the search-engine giant was able to set loose seven Toyota Prius hybrids, all adorned with a dizzying array of odd-looking sensors, onto Highway 1 between San Francisco and Los Angeles for several months without raising suspicion. Each vehicle was piloted by artificial-intelligence software designed to interpret the data collected by the sensors and use it to mimic the decisions made by a human driver. The goal: to fundamentally change the way we use cars.

How so, you ask? Google believes that the use of autonomous vehicles could nearly halve the number of automobile-related deaths — which it estimates at 1.2 million worldwide per year — because computers are theoretically more precise drivers than humans. In addition, the instant reaction time and 360-degree awareness of computer-controlled vehicles would allow them to ride closer together on the highway than vehicles driven by humans, thus reducing traffic congestion. And finally, they can be more fastidious with the accelerator, reducing fuel consumption and carbon emissions considerably.

Essentially, riding in an autonomous car could shave time off your daily commute, reduce your carbon footprint, save you money and save lives in the long run. And you don't even have to lift a finger. Instead of driving, you're a passenger — working, watching television, conversing with friends. Sounds idyllic.

Does this mean that self-directed robot cars, the kind that science-fiction writers have been dreaming about for decades, will hit the streets within a couple of years? No.








While the Google project may be one of the most high-profile demonstrations of autonomous-vehicle research, and one of the most successful to date, the path to a production robotic car still remains uncertain and would require clearing a staggering number of technical and legal hurdles. But plenty of people, in both the academic world and in the research-and-development divisions of carmakers such as GM and Volvo, are working out the kinks.