New details about have emerged, and suggest that the vehicle’s software may have made a risky decision seconds before the collision.
According to a police report, the self-driving Volvo had been travelling along a wide boulevard with a 40mph speed limit.
It was in self-driving mode at the time and was carrying two ‘safety’ drivers, who say it was travelling at 38mph.
The traffic lights that the Uber car was approaching turned yellow as it entered an intersection, where a Honda on the other side of the road made a left turn.
Gadgets and tech news in pictures Gadgets and tech news in pictures
The two vehicles collided, and the Uber was flipped onto its side.
The police report states that the driver of the Honda hadn’t seen the oncoming Uber, and Patrick Murphy, one of the people in the Uber, said a blind spot caused by traffic meant there was no time to react.
Police have said that the Uber car was not at fault, but an eye-witness claims otherwise.
“It was the other driver’s fault for trying to beat the light and hitting the gas so hard,” Brayan Torres told police in a statement, reports . “The other person just wanted to beat the light and kept going.”
Such accounts aren’t always reliable, but Uber’s self-driving cars have previous when it comes to questionable traffic light conduct.
One of them ran a red light in San Francisco last year, an incident that Uber blamed on human error, though two employees said it had been in self-driving mode at the time.
The Arizona incident raises questions about how Uber’s software reacted to the traffic lights.
The thought of its sensors failing to register the changing signals is frightening enough, but the possibility that it chose to speed up to avoid waiting at a red light is far more worrying.
According to a from February, Uber’s driverless cars have “failed to recognise” six sets of traffic lights during San Francisco tests.
The company is currently trialling its system in Arizona, Pennsylvania and California.