In Phoenix, Arizona, you can open an app, tap a button and a car pulls up with nobody in the driver’s seat. It opens its doors, lets you in, drives you across town and drops you off. These are called robotaxis - and they’re already running in cities like Phoenix, San Francisco, Beijing and Wuhan.
Self-driving cars use a stack of sensors to “see” the road. Cameras spot lane lines and traffic lights. Radar tracks moving objects in the rain or dark. A spinning laser called LIDAR sends out millions of pulses a second and builds a 3D map of everything around the car - sometimes detecting a pedestrian or cyclist hundreds of meters away.
The hard part isn’t driving in normal traffic. The hard part is handling rare weird situations: a piece of cardboard blowing across the road, a child running after a ball, a police officer waving by hand. Engineers train the cars on billions of miles of real and simulated driving. Slowly, robotaxis are spreading to more cities every year.
