When self-driving car companies test their cars on the open road they measure the vehicles' success and improvement on a number of factors. One such test is how many miles the car can drive autonomously without human intervention.
Uber's driverless cars require human intervention once every 13 miles, according to company documents obtained by The New York Times. This isn't a great rate, compared with Uber's competitors.
Cruise, GM's driverless car unit, has reported that its cars can go 1,200 miles between interventions, according to the Times; and Waymo, the self-driving car unit of Google's parent company Alphabet, can go 5,600 miles.
This is notable because one of Uber's self-driving cars hit and killed a pedestrian while in full autonomous mode in Tempe, Arizona, on Sunday night. The vehicle had a safety driver behind the wheel, but she didn't appear to be watching the road when the accident occurred. The fatality has some people questioning whether the cars are ready for public roads.
Uber says miles per intervention isn't a measure of the overall safety of its autonomous vehicle testing operations, but rather a way to track the system's improvement. It says different companies may define the interventions differently and the outcome can be arbitrary depending on where and how the cars are tested, such as on an empty highway versus a crowded street.
"We believe that technology has the power to make transportation safer than ever before and recognize our responsibility to contribute to safety in our communities," an Uber spokeswoman said. "So as we develop self-driving technology, safety is our primary concern every step of the way."
When Uber CEO Dara Khosrowshahi joined the company in August, he reportedly thought about shutting down its self-driving car program, according to the Times. But he changed his mind. The CEO was expected to visit Arizona next month to take a ride in one of the company's driverless cars, but that trip has been canceled due to scheduling, according to the Times.
Because of Sunday's fatality, Uber has temporarily halted its self-driving operations in all cities where it's been testing its vehicles, including Tempe, Phoenix, Pittsburgh, San Francisco and Toronto. The local police department and federal agencies are investigating the accident to determine who, or what, was at fault.
"We're heartbroken by what happened this week, and our cars remain grounded," the Uber spokeswoman said. "We continue to assist investigators in any way we can."
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