Search Cars for Sale

Self-Driving Cars: What Is LIDAR and Why Does It Matter?

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.

Russ Heaps
Russ Heaps is an author specializing in automotive, financial and travel news. For nearly 35 years he has covered the automotive industry for newspapers, magazines and internet websites. His resume includes The Palm Beach Post, Miami Herald, The Washington Times and numerous other daily newspapers through syndication. He edited Auto World magazine, and helped create and edit NOPI Street... Read More about Russ Heaps

Sign up for Autotrader newsletters

The best cars and best deals delivered to your inbox

Email Address 

By subscribing, you agree to our privacy policy

Where You Can Buy

Loading dealers...

Leave a Comment

Most Popular Articles

2020 Hyundai Sonata Hybrid: First Look

The 2020 Hyundai Sonata Hybrid jumps to the head of the hybrid class.

Best Truck Deals: June 2022

These are the best deals on trucks for the month of June 2022.

Here Are 5 Great 1980s Performance Cars for Sale on Autotrader

Looking for a fun 1980s car? Look no further.

Search By Style

More Articles Like This