Uber self-driving SUV saw person but didn’t brake

DETROIT — Federal investigators say the autonomous Uber SUV that struck and killed an Arizona pedestrian in March spotted the woman about six seconds before hitting her, but didn’t stop because emergency braking was disabled.

In a preliminary report on the crash, the National Transportation Safety Board said Thursday that emergency braking manoeuvrs are not enabled while Uber’s cars are under computer control, “to reduce the potential for erratic vehicle behaviour.”

Instead, Uber relies on a human backup driver to intervene. The system, however, is not designed to alert the driver.

In the crash, the driver began steering less than a second before impact but didn’t brake until less than a second after impact, according to the preliminary report, which does not determine fault.

A video of the crash showed the driver looking down just before the vehicle struck and killed 49-year-old Elaine Herzberg in Tempe, Ariz.

Uber said in a company release that it has worked closely with the NTSB and is doing an internal review of its self-driving vehicle program. The company also has brought in former NTSB chair Christopher Hart “to advise us on our overall safety culture, and we look forward to sharing more on the changes we’ll make in the coming weeks.”

The NTSB report comes a day after Uber pulled its self-driving cars out of Arizona, eliminating the jobs of about 300 people who served as backup drivers and performed other jobs connected to the vehicles. Uber had suspended testing in Arizona, Pittsburgh, San Francisco and Toronto while regulators investigated the cause of the March 18 crash.

Sensors on the fully autonomous Volvo XC-90 SUV spotted Herzberg while the car was travelling 70 km/h, according to the report.

Herzberg was pushing a bicycle across a boulevard in the darkness when the crash occurred on a part of the road that had no crosswalk and was not lighted, the report said.

She was wearing dark clothing and did not look in the direction of the vehicle until just before impact. A toxicology report showed she tested positive for methamphetamine and marijuana, according to the NTSB. Her bicycle had no side reflectors.