Along a wet and darkened city street drive two robotaxis. Both cars drive themselves, but they perceive the world very differently. The Waymo uses these sensors to generate a detailed 3D model of its surroundings, detecting pedestrians and cars that human drivers might struggle to see. It has no lidar and no radar, just eight cameras housed in pockets of glass. The car processes these video feeds through a neural network, identifying objects, estimating their dimensions, and planning its path accordingly.