How The Eggplant Helps Autonomous Cars See In The Dark

As sensors need assistance detecting oncoming vehicles, paint manufacturers have become key to the new technology

- Jack Kaskey

When Henry Ford revolutionized transportation a century ago with the mass-produced Model T, it came in just one color: black. Eager to customize vehicles to buyers’ tastes, automakers have since cranked out cars in almost every hue imaginable. Now the industry is again concentrating on its original color to address a dangerous blind spot of self-driving cars: They can’t see black very well.

Dark colors absorb light, which means the navigating lasers of autonomous vehicles don’t quite bounce off—or enable detection of—black cars. Therein lies a potential windfall for old-school companies that make paint. The world’s largest producer of vehicle coatings, PPG Industries Inc., is engineering a paint that allows the near-infrared light emitted by lasers to pass through a dark car’s exterior layer and rebound offa reflective undercoat—making it visible to sensors. PPG got the idea from the purple eggplant, which uses a similar trick on farms to keep cool on hot days.

PPG and other companies see a lucrative opportunity in solving one of the most intractable problems of driverless technology—and a way to ensure demand for their products even as the number of cars on the road may dwindle.

Yet this isn’t just a challenge for tomorrow’s vehicles. Cars that can already park themselves, apply brakes, avoid obstacles, and find the correct lane rely on sensors and transmitters hidden in bumpers and side panels. Paints and coatings can interfere with or improve the performance of those sensors, says Barry Snyder, chief technology officer of Axalta Coatings Systems Ltd. “Autonomous cars create some significant issues from a paint standpoint,” he says. “But you have technology going into smart cars today that already creates challenges we need to respond to.”