“We have introduced a headlight system that can see through rain” and other precipitation, says Srinivasa Narasimhan, an associate professor at Carnegie Mellon University’s Robotics Institute. Narasimhan’s team worked with researchers from Texas Instruments and France’s Paris Institute of Technology, with funding from the Office of Naval Research, the National Science Foundation, the Samsung Advanced Institute of Technology and Intel Corp.
Narasimhan is the first to admit that the concept sounds a bit farfetched. The key is that even a sheet of heavy rain is still mostly empty space. “When we see rain, we see streaks, so it looks like the precipitation is inhabiting the air very densely,” Narasimhan says. “But if you look at an instantaneous snapshot of rain it’s actually very sparse. This is the case even in a thunderstorm.”
The headlight is actually an array of bulbs. The system uses a digital camera to track the motion of individual raindrops or snowflakes and then applies a computer algorithm to predict where each bit of precipitation will be a few milliseconds later. It deactivates bulbs that would otherwise illuminate the drops or flakes in their predicted positions.