National Transportation Safety Board

It's day five of the Tempe Police Department's investigation into Uber's self-driving car crash, the accident that resulted in the first fatality of a pedestrian from a car in full autonomous mode.

And there's still no clear answer as to what went wrong.

The Arizona police, along with federal investigators, have been examining the vehicle and accident site, while also gathering information about the technology in the car, the vehicle operator and the pedestrian. They've also been studying a video that captured the crash Sunday night from the car's dashboard camera.

That video was released to the public on Wednesday. It shows footage of the pedestrian, Elaine Herzberg, walking her red bike loaded with bags across a dark road. It stops at the moment of impact. The video also shows the vehicle operator, Rafaela Vasquez, sitting at the wheel constantly glancing down at her lap. She looks up just as the car collides with Herzberg. The video is graphic and difficult to watch.

While it's unclear how a human driver would've reacted, some autonomous-vehicle experts who've watched the video say the driverless car's broad array of sensors should have detected Herzberg before she was hit.

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Cortica, a technology company that develops autonomous artificial intelligence, analyzed the video and provided its evaluation exclusively to CNET. Its system detected Herzberg at 0.9 second before impact when the car was about 50 feet away. Cortica's CEO, Igal Raichelgauz, said that would have been enough time for an autonomous vehicle to react and save Herzberg's life.

"The advantage of machine response time and control, the right actions could be made to certainly mitigate the damage," Raichelgauz said.

Tempe police say the car didn't slow down or swerve as Herzberg appeared on the road. It hit her traveling at 38 mph.



"The video is disturbing and heartbreaking to watch, and our thoughts continue to be with Elaine's loved ones," an Uber spokeswoman said in an emailed statement. "Our cars remain grounded, and we're assisting local, state and federal authorities in any way we can."

A work in progress



Driverless cars are equipped with a system of cameras, radar and lidar sensors that allow them to "see" their surroundings and detect traffic, pedestrians, bicyclists and other obstacles. If confronted with a pedestrian, self-driving cars are supposed to stop. These sensors are said to work as well at night as in daylight.

"Although this video isn't the full picture, it strongly suggests a failure by Uber's automated driving system," said Bryant Walker Smith, a University of South Carolina law professor who studies autonomous vehicles. "The victim is obscured by darkness -- but she is moving on an open road. Lidar and radar absolutely should have detected her and classified her as something other than a stationary object."



The company Velodyne made the lidar system that was on Uber's self-driving car involved in the crash. However, CEO David Hall and President Marta Hall said they believe the accident wasn't cause by the lidar.

"We are as baffled as anyone else," Marta Hall said in an email. "Certainly, our Lidar is capable of clearly imaging Elaine and her bicycle in this situation. However, our Lidar doesn't make the decision to put on the brakes or get out of her way.

"It is up to the rest of the system to interpret and use the data to make decisions," she added. "We don't know what sensors were on the Uber car that evening, if they were working, or how they were being used."

For the most part, testing of autonomous technology has shown driverless cars to be safe. But it's still a work in progress. The vast majority of vehicle tests haven't been done on public roads, and the cars are still learning how to drive.

"Driving a car can seem like a rote process, but it is not," said Timothy Carone, a driverless car expert and associate teaching professor at the University of Notre Dame's Mendoza College of Business. "We make complex decisions and value judgments continually when we are behind the wheel."

As autonomous systems mature and become more capable of handling unusual situations, they'll get better at making those complex decisions, Carone said. But, he added, that could take years.

"As our society transitions to using more systems like driverless cars, pilotless airplanes, driverless trucks and trains, and weapons, the accidents will continue happening," Carone said.

The investigation

For now, 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 Tempe police are working with Uber representatives, the National Transportation Safety Board and the US Department of Transportation's National Highway Traffic Safety Administration in their investigation to determine who, or what, was at fault for the accident. Velodyne representatives also said they're "at the service" of the engineers and investigators in the case.

Initially, Tempe Police Chief Sylvia Moir said it would've been difficult to avoid Herzberg because she was emerging from the shadows, according to the San Francisco Chronicle.

From viewing the videos, Moir said, "It's very clear it would have been difficult to avoid this collision in any kind of mode (autonomous or human-driven) based on how she came from the shadows right into the roadway."

However, Tempe police later released a statement walking back those initial assertions and said it has yet to pinpoint responsibility for the collision.

"Chief Moir and the Tempe Police Department would like to reaffirm that fault has not been determined in this case," Tempe Police Sgt. Roland Elcock said in the statement. He added the investigation will look into driver interaction with the vehicle and opportunities for the vehicle or driver to detect Herzberg before she was struck.

"We hate to draw conclusions," Elcock said in a press conference Monday. "A conclusion will come at the end of the investigation."

First published March 22 at 5:51 p.m. PT.

Update, March 23 at 10:05 p.m.: Adds comment from Tempe Police Chief Sylvia Moir and background information.

Update, March 23 at 12:37 p.m.: Adds comment from Velodyne President Marta Hall and additional background information.

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