Look Mom, No Lights!

Ford Motor Co. has begun testing a prototype self-driving car at night without its headlights turned on, forcing the vehicle to rely on lidar and high-resolution 3-D mapping to navigate roads and stay in its lane.

The test car, a specially equipped version of a Fusion hybrid midsize sedan, is being run through its paces at Ford’s Arizona proving grounds. Without lights, the carmaker notes, the vehicle’s forward-looking cameras don’t work effectively.

New 3-D maps provide precise information about the road’s lanes and topography as well as details about landmarks such as signs, buildings and trees. Lidar (light detection and ranging) pulses pinpoint the vehicle’s location on the map, sending out 2.8 million laser pulses per second to scan the surrounding environment. Additional data from radar is used to supplement the lidar information.

Ford says the lightless test vehicle was able to drive on its own as well at night with lidar as it does during the day, Citing statistics from the U.S. National Highway Traffic Safety Administration, Ford notes that the fatality rate during “dark hours” is three times higher than the daytime rate.