Smart headlights to help drivers see through rain developed
Researchers have developed technology for smart car headlights that let drivers see through heavy rain or snow. The system tracks motion of raindrops and then applies an algorithm to predict where those particles will be a few moments later. It then deactivates light beams that would reflect off the particles in their predicted positions, preventing glare that would distract drivers.
Washington, Jul 4 (PTI) Scientists, including one of Indian origin, have developed a smart headlight system for the first time that can help drivers see through heavy rain or snowfall and safely navigate roads during stormy nights. The system invented by researchers at Carnegie Mellon University (CMU) in the US improves visibility by constantly redirecting light to shine between particles of precipitation. It prevents the distracting and sometimes dangerous glare that occurs when headlight beams are reflected by precipitation back toward the driver. "If youre driving in a thunderstorm, the smart headlights will make it seem like its a drizzle," said Srinivasa Narasimhan, CMU associate professor of robotics. The system uses a camera to track the motion of raindrops and snowflakes and then applies a computer algorithm to predict where those particles will be just a few milliseconds later. The light projection system then adjusts to deactivate light beams that would otherwise illuminate the particles in their predicted positions. "A human eye will not be able to see that flicker of the headlights," Narasimhan said. "And because the precipitation particles arent being illuminated, the driver wont see the rain or snow either," To people, rain can appear as elongated streaks that seem to fill the air. To high-speed cameras, however, rain consists of sparsely spaced, discrete drops. That leaves plenty of space between the drops where light can be effectively distributed if the system can respond rapidly. Lab tests demonstrated that the smart headlight system could detect raindrops, predict its movement and adjust a light projector accordingly in 13 milliseconds. At low speeds, such a system could eliminate 70 to 80 per cent of visible rain during a heavy storm, while losing only five or six per cent of the light from the headlamp. To operate at highway speeds and to work effectively in snow and hail, the systems response will need to be reduced to just a few milliseconds. Lab tests have demonstrated the feasibility of the system and the researchers are confident that the speed of the system can be boosted. For instance, the test apparatus couples a camera with an off-the-shelf DLP projector. Road-worthy systems likely would be based on arrays of light-emitting diode (LED) light sources in which individual elements could be turned on or off, depending on the location of raindrops. 