For the first time, one of Google's self-driving cars was involved in a minor crash that caused minor injuries. However, Google said the crash was not the fault of the self-driving vehicle.
Google cars have been in minor crashes previously, but never with injuries.
The incident, which occurred July 1 during the evening rush hour in Mountain View, Calif., near Google's headquarters, happened when one of the Google fleet's Lexus self-driving cars was waiting behind stopped traffic at a green light, according to a blog post about the incident by Chris Urmson, director of Google's self-driving car project. The waiting Lexus was struck from behind by a car that slammed into it at 17 mph without ever using its brakes, Urmson wrote.
"Our self-driving cars are being hit surprisingly often by other drivers who are distracted and not paying attention to the road," he wrote in the post. That's what apparently happened in this incident, he explained.
"The light was green, but traffic was backed up on the far side, so three cars, including ours, braked and came to a stop so as not to get stuck in the middle of the intersection," he wrote. "This certainly seems like the driver was distracted and not watching the road ahead. Thankfully, everyone in both vehicles was okay, except for a bit of minor whiplash, and a few scrapes on our bumper. The other vehicle wasn't so lucky; its entire front bumper fell off."
The silver lining in the incident, however, is that the Google self-driving car project, which first began in 2010, is now accumulating enough data that statistics can be compared with human-driven vehicles, wrote Urmson. "But we're now driving enough — and getting hit enough — that we can start to make some assumptions about that real crashes-per-miles-driven rate; it's looking higher than we thought."
Google's cars are self-driving about 10,000 miles per week, which is about what a typical American adult drives in a year, he wrote.
"It's particularly telling that we're getting hit more often now that the majority of our driving is on surface streets rather than freeways; this is exactly where you'd expect a lot of minor, usually-unreported collisions to happen," wrote Urmson. "Other drivers have hit us 14 times since the start of our project in 2009 (including 11 rear-enders), and not once has the self-driving car been the cause of the collision."
Over and over again, the cause of the crashes has been human error and inattention, he wrote.
In May, Urmson reported that Google's self-driving cars were so far involved in 11 collisions over the six years and the 1.7 million miles the company has been testing the vehicles, according to an earlier eWEEK story. All of the accidents were minor, caused no injuries and resulted when a human driver was behind the wheel, he wrote at the time.
Google is one of several companies testing self-driving vehicles in California. Others include Delphi, Tesla, Audi, Daimler Benz and Nissan. The companies are working on developing cars that will one day be capable of operating on public roads in an autonomous fashion with very-little-to-no human involvement.
The goal is to improve vehicle safety with technologies that help remove blind spots, detect objects at greater distances and respond to dangerous situations much faster than human drivers. Google has claimed that its autonomous vehicles are capable of detecting objects two football fields away in all directions.
In May 2014, Google announced that it was beginning work to build its next generations of the vehicles on its own, rather than using modified cars from existing automakers.
The self-driving vehicle project was launched by Google in 2010 as a research effort to see how such vehicles could be used to save peoples' lives, cut driving time and curb carbon emissions and pollution. The project began using Toyota Prius hybrid vehicles with trained operators all over the roads and highways of California, and since has expanded to other vehicles.
The vehicles will be equipped with special sensors and hardware that give them their self-driving capabilities while also including special safety features, such as a flexible windshield and a foam-like front end to protect pedestrians in the event of a crash, according to Google. The vehicles will also include electric batteries for propulsion as well as primary and backup systems for steering and braking.
The first artist's renderings and photos of the vehicles display rounded vehicles that look a bit like stylized versions of early Volkswagen Beetles. Previous Google self-driving vehicles so far have included Toyota Prius and Lexus models.