UBER’S USE OF FEWER SAFETY SENSORS SPARKS QUESTIONS AFTER CRASH

PITTSBURGH: When Uber decided in 2016 to retire its fleet of selfdriving Ford Fusion cars in favour of Volvo sport utility vehicles (SUV), it also chose to scale back on one notable piece of technology: the safety sensors used to detect objects in the road.

That decision resulted in a selfdriving vehicle with more blind spots than its earlier generation of autonomous cars, as well as those of its rivals, according to interviews with five former employees and four industry experts who spoke for the first time about Uber’s technology switch.

Driverless cars are supposed to avoid accidents with lidar – which uses laser light pulses to detect hazards on the road – and other sensors such as radar and cameras.

The new Uber driverless vehicle is armed with only one roofmounted lidar sensor compared with seven lidar units on the older Ford Fusion models Uber employed, according to diagrams prepared by Uber.

In scaling back to a single lidar on the Volvo, Uber introduced a blind zone around the perimeter of the SUV that cannot fully detect pedestrians, according to interviews with former employees and Raj Rajkumar, the head of Carnegie Mellon University’s transportation centre who has been working on self-driving technology for more than a decade.

The lidar system made by Velodyne – one of the top suppliers of sensors for self-driving vehicles – sees objects in a 360-degree circle around the car, but has a narrow vertical range that prevents it from detecting obstacles low to the ground, according to information on Velodyne’s website as well as former employees who operated the Uber SUVS.

Autonomous vehicles operated by rivals Waymo, Alphabet’s selfdriving vehicle unit, have six lidar sensors, while General Motors’ vehicle contains five, according to information from the companies.

Uber declined to comment on its decision to reduce its lidar count. An Uber spokesperson said this week: “We believe that technology has the power to make transport safer and recognise our responsibility to contribute to safety in our communities. As we develop self-driving technology, safety is our primary concern every step of the way.”

Uber referred questions on the blind spot to Velodyne. Velodyne acknowledged that with the rooftop lidar there was a roughly 3m blind spot around a vehicle, saying that more sensors were necessary.

“If you’re going to avoid pedestrians, you’re going to need to have a side lidar to see those pedestrians and avoid them, especially at night,” said Marta

Hall, president and chief business development officer at Velodyne.

The safety of Uber’s self-driving car programme is under intense scrutiny since Elaine Herzberg, 49, was killed last week after an Uber Volvo XC90 SUV operating in autonomous mode struck and killed her while she was jaywalking with her bicycle in Tempe, Arizona.

The precise causes of the Arizona accident are not yet known, and it is unclear how the vehicle’s sensors functioned that night or whether the lidar’s blind spot played a role.

The incident is under investigation by local police and federal safety officials.

Uber has said it was co-operating in the investigation and had pulled all of its autonomous cars off the road, but provided no further details about the crash.

Like the older Fusion model, Uber’s top competitors place multiple, smaller lidar units around the car to augment the central rooftop lidar, a practice experts in the field say provides more complete coverage of the road.

The earlier Fusion test cars used seven lidars, seven radars and 20 cameras. The newer Volvo test vehicles used a single lidar, 10 radars and seven cameras, Uber said.

Since Uber launched a selfdriving car programme in early 2015, it has tried to catch up with Waymo, which began working on the technology in 2009.

Uber management moved swiftly even as some car engineers voiced caution, according to former employees, in a rush to get more cars driving further.

Seven experts who have reviewed the crash agree that a selfdriving system should have seen Herzberg and braked.

She had crossed nearly the entire four-lane, empty road before being struck.

“Radar is supposed to compensate for (the lidar’s) blind spot,” said Rajkumar.

Uber declined to comment on its radar system. Volvo, owned by China’s Geely, also declined to comment.

A Ford spokesman said the company was not involved in Uber’s use of the Fusion or the selfdriving technology employed on the cars. – Reuters/african News Agency (ANA)