Crash-Testing Driverless Cars in a Robot City

A mother pushing a baby carriage jaywalks across a busy city street. Cutting between two parked cars and partially obscured by a bus, she edges her stroller into traffic before freezing as a speeding car bears down on her. Will the car stop in time? Or will it mow down mother and child? It doesn’t really matter: The mom is a robot, and the car is a driverless vehicle cruising down a fake street in a mock town.

Welcome to M City, a soon-to-open 23-acre mini-metropolis at the University of Michigan, where automakers can test autonomous cars to prepare for the driverless future expected within a decade. Seeking to replicate a modern city’s chaos—traffic jams, unpredictable pedestrians, weaving cyclists—M City starts running on July 20 and has carmakers and tech companies queuing up to conduct research on its roads.