Researchers at Stanford University, California develop a revolutionary laser imaging technique that allows self-driving cars to see beyond corners and avoid potential danger.
To understand how it works, just imagine this scenario. While navigating through an unfamiliar neighborhood, an autonomous vehicle stops before reaching a blind corner.
Apparently, its system has detected a child running across the road, right where the car is about to make its turn. Had the situation occurred without laser technology involved, another young life would have been added to the death toll.
Surprisingly, statistics reveal that traffic accidents claim more than 1.2 million lives a year, making it the world's second leading cause of death among children at age 5 to 14.
Should the group become successful in creating a system using the new laser technology, there is a great chance that these alarming figures would become a thing of the past.
"This is a big step forward for our field that will hopefully benefit all of us," says Gordon Wetzstein, assistant professor of electrical engineering at SU and lead author of the study.
How The Laser-Based System Detects Looming Road Accidents
To "magically" see through corners, the researchers installed a laser device right next to a photon detector that's sensitive enough to capture the smallest particle of light.
With everything in place, they began shooting laser beams at a solid wall where they are reflected on a hidden object. From there, they bounce back to the wall and to the detector.
The entire process, also known as a "scan", takes anywhere between a couple of minutes and an hour to complete. At this point, the captured photons are merely blobs without any distinct form.
Using an algorithm, which the group claims as more effective than existing ones, the blobs are turned into sharp images in less than a single second.
In a paper published March 5 on international science journal Nature, researchers refer to the recently-discovered technique as "confocal non-line-of-sight imaging" or C-LOS imaging.
Laser Cameras That See Through Corners And Walls
This is not the first time that bouncing lasers have been used in detecting hidden objects. As early as December 2015, a group at Heriot-Watt University, Scotland placed laser devices inside cameras to make them see and record moving objects around corners and through walls.
The Scottish researchers came up with an incredibly fast system, with a laser device that shoots an average of 67 million pulses per second and a highly sensitive camera capable of capturing even the tiniest photon particles at a rate of 50 picoseconds.
Similar to SU's technology, this laser-based camera system would prove useful in making self-driving cars much safer from collisions.
"If the other vehicle or person is arriving too fast, implying that there could be a collision, then the system could feed this information to the car, which could then autonomously decide to slow down," explains Daniele Faccio, a physicist at HWU and lead author of the 2015 study.
More details of their laser-based system are found in a paper published Dec. 7 on research journal Nature Photonics.
