While much has been made of Google's driverless cars, it will likely still be years before a fully autonomous vehicle takes you home after you've had one too many drinks at the bar. But when it does arrive, you can tip DARPA for the ride.
In 2004, DARPA staged its first Grand Challenge for autonomous vehicles in the Mojave Desert. The competition expanded in 2007 to an urban competition where the contestants had to obey traffic rules, park and interact with other driverless vehicles.
Last year, Nissan got a permit to test autonomous vehicles on public roads in Japan, where the technology is seen as potentially helping its elderly population. The Yokohama-based company plans to introduce a self-driving car by 2020.
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