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Ford Tests Its Self-Driving Car In Total Darkness Using LiDAR Tech (fortune.com)
An anonymous reader writes: Using a combination of radar, cameras, and light-sensitive radar called LiDAR, one of Ford's self-driving cars has successfully navigated a winding road at night and without headlights. LiDAR works by emitting short pulses of laser light -- 2.8 million laser pulses a second -- so that the vehicle's software can create a real-time, high-definition 3D image of what's around it to determine the best driving path. Ford's self-driving cars come equipped with high-definition 3D maps, which include information about road markings, signs, geography, landmarks, and topography. If a vehicle isn't able to see the ground due to inclement conditions, it will detect above-ground landmarks to locate itself on the map. Ford's self-driving cars equipped with the LiDAR radar system are particularly noteworthy because they can operate without the usual cameras that depend on sunshine and street lamps.
So one of the problems with modern depth sensors is handling sunlight. Blackbody radiation can cause all kinds of noise in the signal that is bounced back at the camera from a laser. This makes it harder, not easier, for a lot of depth perception tech to work in good lighting conditions.
Driving at night should, for the most part, be easier for many systems than driving during the day.
Not necessarily. Lidar can use multiple beams and multiple wavelengths to work around this.
http://velodynelidar.com/faq.h...
"Velodyne's LiDAR sensors work well in snow, sleet, and rain. The multiple beam approach of Velodyne's LiDAR sensors with laser beams with millions of laser beams at different angles enables to find "holes" in-between the snowflakes to "see" the environment. An inferior LiDAR with only one or a few laser beams would not work as well as one with 16, 32 or 64 laser beams."