In the lexicon of self-driving cars, LIDAR is a common term, but hardly a household name. Is it something families discuss around the dinner table? Probably not, but in the world of autonomous vehicles (AVs), it’s the Rosetta Stone. Indeed, it’s the key breakthrough for cars safely driving themselves.
As a word, it may appear in different forms (LIDAR, LiDAR or Lidar) in different publications, but whichever spelling is used, it is critical to AVs safely operating on public streets.
What Is It?
LIDAR stands for “light detection and ranging.” If you’ve seen a photo of an AV with the big circular rig perched on the roof, you’ve seen a LIDAR unit. It’s literally the eyes in the back of an AV’s head, as well as in front and 360 degrees all around. Think of it as extremely sensitive sonar that uses light rather than sound to map its surroundings.
How Does It Work?
Just as sonar detects objects and their distance by emitting sound waves and then measuring how quickly those waves return after bouncing off an object, LIDAR uses rapid pulses of laser light to achieve the same end. Radar works similarly using radio waves. Light, however, travels much quicker than sound or radio waves, providing a more rapid response. All use what are essentially echoes to see what otherwise couldn’t be seen.
All three of these echo detection systems measure the time it takes for their signals to return. Because short bursts of light can be sent, received on their return and measured more quickly, LIDAR is extremely effective in accurately mapping the ever-changing world surrounding an AV in traffic.
When operated from an airplane or satellite, LIDAR can actually penetrate cloud cover or even a forest canopy to see the earth’s surface. The capability to see clearly through fog, rain, snow and so forth is what makes LIDAR such an essential technology for AVs.
LIDAR, Its Inventor and AVs
Currently, the LIDAR technology widely used among AV developers comes from the leading maker of LIDAR sensors, Velodyne. Forbes recently identified Velodyne and its founder and inventor Dave Hall as key to today’s AV revolution. According to Forbes, it was the multibeam spinning LIDAR sensor Hall patented in 2006 that catapulted the AV movement forward. Without it, developers of self-driving cars would still be stuck trying to figure out how an AV could possibly read and interpret its surroundings in all types of weather and light conditions with just cameras and radar.
Without LIDAR, and specifically Hall’s spinning LIDAR sensor, there would be little optimism that self-driving cars might be in our foreseeable future. There are still plenty of obstacles standing between now and a future filled with AVs, but being able to accurately see what’s surrounding them is no longer an issue for cars that drive themselves.