Uber once again grounded its self-driving car experiment Friday following a vehicle collision in Tempe, Arizona in which one of the autonomous Volvos landed on its side.
TechCrunch reported on the crash, and Uber gave a statement saying "We are continuing to look into this incident and can confirm we had no backseat passengers in the vehicle." They also confirmed that there was a person behind the wheel, but the car was in autonomous mode at the time of the crash.
Bloomberg reported, via the Tempe Police Department, that the Uber vehicle was not responsible for the collision. "Another car failed to yield for the Uber car, causing the autonomous vehicle to flip on its side, according to the police report."
This does not adequately answer the question of how the vehicle flipped onto its side, and the accident may end up proving to be an example of how self-driving technologies come up short in complex situations. As the Washington Post puts it, sharing the road with human motorists "will put autonomous vehicles in situations that may seem simple but are actually difficult to navigate, such as what to do when another vehicle honks its horn."
Uber took most of its self-driving fleet to Arizona in December following their short-lived attempt to skirt DMV regulations here in SF. More recently the company applied for and received testing permits from the California DMV for two autonomous vehicles that had been, until Friday, being tested on the streets of San Francisco. Uber currently has 43 self-driving vehicles, including a fleet in Pittsburgh, where they have been picking up passengers for several months.
It is unclear for how long Uber plans to keep the cars off the road following this latest incident.