

Image Source: Flickr (Roman Boed)



There was a lot of buzz in the media yesterday when it was revealed that four of the 50 self-driving cars deployed in California had been involved in accidents since hitting the streets last September. Three of those automobiles were using sensors provided by Google , though only two of the four accidents occurred when the self-driving cars were in control. None of the accidents were the fault of the self-driving cars or their drivers, though the lack of details made available to the public didn't sit well with those keeping a close eye on the program. To set the record straight, Chris Urmson, director of Google's self-driving car program, posted an informative article about what Google's learned after 1.7 million miles of testing.That includes both manual and autonomous operation among a fleet of more than 20 self-driving cars, with the majority of the miles (nearly a million) being self-driven. Out of all that driving, Google's autonomous cars have only been involved in 11 minor accidents causing light damage and no injuries. And out of those 11 incidents, the self-driving car was never the cause of the accident, according to Urmson."Rear-end crashes are the most frequent accidents in America, and often there’s little the driver in front can do to avoid getting hit; we’ve been hit from behind seven times, mainly at traffic lights but also on the freeway. We’ve also been side-swiped a couple of times and hit by a car rolling through a stop sign," Urmson says. "And as you might expect, we see more accidents per mile driven on city streets than on freeways; we were hit 8 times in many fewer miles of city driving."Intersections can be particularly dangerous, as they've accounted 21 percent of the fatalities and about half of the serious injuries on U.S. roads over the last several years. To account for this, Google's cars are programmed to pause for a brief moment after a light turns green before heading into the intersection.There are other safety protocols in place as well, though at the end of the day, Urmson alludes to distracted drivers being the real problem, not self-driving cars. Google's "safety drivers routinely see people weaving in and out of their lanes; we've spotted people reading books, and even one playing a trumpet," Urmson added.This is where self-driving cars have a distinct advantage -- 360-degree visibility and sensors that keep track of other cars, cyclists, and pedestrians up to nearly 200 feet away.