A Tesla Model S driver was recently killed in an accident between his car and a trailer crossing the highway. The car's Autopilot feature was turned on, but seemingly neither it nor its driver noticed the obstacle on the road and the brakes weren't engaged.
In a post on the company’s website, Tesla expressed its "deepest sympathies" for the family of driver while also announcing that the US NHTSA has launched a preliminary investigation into the accident.
According to the company, the driver was going down the highway with the Autopilot system turned on. At some point, neither the driver nor the car’s Autopilot took notice of a tractor crossing the highway perpendicular to the Tesla. The error, on the car's part, seems to have occurred due to a combination of factors including the white paint job of the tractor, brightly lit against a bright sky, and the high ride height of the trailer that the tractor was pulling. The company says these are "extremely rare circumstances" that its Autopilot feature had not encountered before. And it's this type of situation where the driver's attention and focus become very important.
The Tesla Model S drove straight under the trailer without engaging the brake, crashing off the road afterwards. Its driver died at the scene.
In its post the company repeatedly stressed that Autopilot is an assistive technology and not one that’s meant to replace the driver. Repeated warnings tell the driver to remain attentive and keep their hands on the steering wheel, with the car slowing down and stopping if it does not detect the driver’s hands.
It’s also worth mentioning that the car’s Autopilot relies on a number of optical cameras and RADAR to determine the obstacles around it. Tesla’s cars do not feature LiDAR, like Google cars do. LiDAR is a much more expensive, laser-based guiding system whose main advantage is that it should be able to recognize its surroundings in whatever weather and lighting conditions. Recently, Elon Musk said he believes LiDARs don’t make sense on cars.
The downsidse of LiDAR are its price and limited range, so even if it had been present it’s not at all clear it would have made a difference in this case.
Autonomous vehicles are seen as possibly the much safer alternative to human drivers, something that Tesla reiterates in its public statement. The company says its Autopilot has driven 130 million miles, with this being the only fatality. Around the world, on average, human drivers cause a fatality every 60 million miles. Recently, Elon Musk said that Tesla’s Autopilot feature was “almost twice as good as human drivers”. These numbers seem to show it’s actually better. Unfortunately though, the technology is still not good enough to save us in every situation.