Dashed box: the ball as the simulator knows it, drawn only when it is in frame and nothing stands in front of it — what a perfect detector would report. Map: the floor the camera covers, and the ring where the robot last saw the ball. Reading the ball from the camera, System 1 goes by that ring: it keeps the ball in view with its head on the way, and only when the ball has been out of view too long does it stop, look where it last saw it, and look around if it is not there.