Optics of Autonomous Vehicles

Cameras and lidars are playing key roles in the development of self-driving cars. Tesla Motors of Palo Alto, CA (USA), used a front-looking camera in the autopilot system it introduced in 2014, and the new version announced in October 2016 includes eight cameras mounted around the car.

Experimental self-driving cars being tested by Google and others also sport roof lidars for three-dimensional mapping.

The optical systems are part of a suite of sensors that work with an onboard computer to map the local environment and steer the vehicle through a dynamic environment that contains traffic signals, pedestrians, other cars, tractor trailers, and even wild animals. The ultimate goal is a robotic system that drives better than error-prone humans, but most observers think that's many years away.

Further upgrades to fully autonomous cars are in our future but we aren't there yet, as shown tragically by the fatal full-speed crash of a Tesla into a tractor trailer making a turn across a divided highway in Florida in May 2016.

"Neither the autopilot nor the driver noticed the white side of the tractor trailer against the brightly lit sky, so the brake was not applied," Tesla wrote in a 30 June 2016 blog post. The car was headed east on a sunny afternoon, and the driver was not paying attention. The car's one forward-looking camera missed the color difference between the truck and the sky, perhaps because it was monochrome.

The concept of self-driving cars has been gaining attention. General Motors says it will introduce "Super Cruise" technology in its Cadillac CT6 model in 2017. Uber is testing its own autonomous cars in Pittsburgh, PA (USA). In October, Uber's Otto subsidiary claimed the first commercial delivery by a self-driving truck, a modified Volvo 18-wheel tractor trailer. It drove more than 50,000 cans of beer on 120 miles of Colorado (USA) highway from Fort Collins to Colorado Springs, passing through Denver.

But don't expect robocars to become routine yet.

"Lots of progress has been made in the past few years, but we still have quite a long way to go before we can fully automate the driving function," says Raj Rajkumar, director of the Technologies for Safe and Efficient Transportation Center at Carnegie Mellon University (USA). He predicts gradual progress, with cars coming on the market in three years that can drive themselves in "geographically fenced regions" such as limited-access highways, where there are no pedestrians, bicycles, or other potential perils.

In an article in the January 2017 issue of SPIE Professional Jeff Hecht, a science and technology writer, shows how cameras and lidars are playing key roles in the development of self-driving cars.

Read the full article about autonomous vehicles in SPIE Professional.