The system builds on the navigation systems used in other self-driving cars, using 3D laser scanning technology to create a real-time map of the environment, then comparing that real-time map to a pre-drawn map stored in the system. By making thousands of comparisons per second, they're able to determine the vehicle's location within a few centimeters. The software converts the map data into a 3D picture much like a video game. The car's navigation system can then compare these synthetic pictures with the real-world pictures streaming in from a conventional video camera.
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