"Smart" Headlight System Sees through Heavy Rain, Snow

Researchers at Carnegie-Mellon University have developed a headlamp system that analyzes falling raindrops and alters its beam to shine between them.

The system uses a camera to track the motion of individual raindrops or snowflakes and estimate where those particles will be a few milliseconds later. The technology then turns on and off the multiple projector beams to avoid the particles.

The beam flickers too quickly to be detected by the human eye, according to the researchers at Carnegie-Mellon's Robotics Institute. At low vehicle speeds, the system eliminates light bounceback from at least 70% of the visible rain during a heavy storm, thus providing the driver with a clearer view ahead.

A laboratory version of the system consists of a light projector, 50:50 beam splitter and camera. It can predict raindrop trajectories and alter a light beam within 13 milliseconds. But developers say such adjustments would have to occur within a few milliseconds to be effective at highway speeds.

The researchers envision a headlamp unit consisting of multiple LEDs that could be turned on and off by the system. They currently are engineering a more compact version of the technology for tests in a vehicle. The developers note that it may be possible to develop LEDs and image sensors on a single chip to reduce cost.

The Robotics Institute's research was sponsored by the National Science Foundation, Office of Naval Research, Intel Corp. and the Samsung Advanced Institute of Technology.