A new video released online shows the moment Google's autonomous vehicle slammed into a bus in Mountain View, California.
Uploaded by The Associated Press, the YouTube video contains both surveillance footage from the bus in question, as well as images of the damage caused to Google's autonomous prototype.
Google's fleet of self-driving cars has logged over two million miles in testing and clocked up an average of 10,000-15,000 autonomous miles per week on public streets in Mountain View, California and Austin, Texas.
While accidents have been reported in the past, these have usually been caused by standard drivers on the road causing minor issues such as rear-ending the car.
Everything was going well until Valentine's Day on February 14 this year. As the video below shows, Google's self-driving car hit a bus, leading to damage to the vehicle.
It's difficult to say who is at fault based purely on the footage. The bus driver was controlling his vehicle one-handed while munching on a sandwich -- and without a seatbelt, to boot -- but either way, Google acknowledged the accident within the firm's self-driving car February report (.PDF).
Within the report, Google says the vehicle was driving autonomously and pulled towards a right-hand curb to prepare for a right turn. The car's sensors then detected sandbags near a storm drain, and as these obstacles were blocking the car's path, it came to a stop.
The autonomous vehicle then waited while other cars passed, before angling back to the centre of the lane at roughly 2mph -- and managed to collide with a passing bus traveling at 15mph. Google's car sustained body damage to the left front fender, left front wheel and a driver-side sensor due to the crash.
"Our car had detected the approaching bus but predicted that it would yield to us because we were ahead of it," the report states.
"Unfortunately, all these assumptions led us to the same spot in the lane at the same time. This type of misunderstanding happens between human drivers on the road every day. This is a classic example of the negotiation that's a normal part of driving -- we're all trying to predict each other's movements."
The test driver thought the bus would let them pass, and the bus driver probably assumed they were staying put. In the world of driving, full of people cutting each other up, road rage and a lack of indicator use -- at least in the UK -- this incident seems rather minor. However, if the self-driving car will ever be given free reign on our roads, each incident needs to be analysed.
After scrutinising the incident, of which Google said it "clearly bear[s] some responsibility," the tech giant has refined its program to improve traffic prediction while on the road.
"Our cars will more deeply understand that buses and other large vehicles are less likely to yield to us than other types of vehicles, and we hope to handle situations like this more gracefully in the future."
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