Headlights That Dodge Rain Are Tomorrow's Newest, Coolest Safety Feature

By Blake Z. Rong | July 10, 2012
Rain-dodging headlights might seem like a frivolous impossibility, but anyone who's driven in a downpour (not us, firmly ensconced in Southern California) will understand how annoying the glare of the headlights against raindrops and snow is, making bad visibility even worse. But researchers at Carnegie Mellon University have developed smarter headlights that see around particles, eliminating the streaks that make us look like we're warping into hyperspace but eventually become distracting and unsafe. The system consists of a video camera, a digital projector, a beam splitter, and a computer, loaded with an algorithm that can predict the falling of raindrops. The video camera captures the falling rain (it all starts to sound poetic after a while) as it launches towards the view of the headlights, outlining each individual raindrop on the projector. (The projector display looks like an especially hellish game of Tetris.) Then, the computer tells the lights to turn off imperceptibly—within the span of 13 milliseconds, too short to be distinguished by human eyes. Does it work? Well, sorta. The system itself performed as expected, but the headlights themselves aren't as bright or far-reaching as your average halogen lights. Blame the resources needed for adaptive headlights to turn on and off so quickly as to not be detected. Also, the accuracy of detecting raindrops fell drastically as speed increased, with only 15 percent of drops sighted at 60 mph.
But with newer headlight technology happening fast—witness BMW's laser headlights, or Audi's proliferation of LEDs—don't be surprised if a similar rain-thwarting technology makes its way to a German luxury car in a few short years. Source: Carnegie Mellon