Keith Naughton:

It’s nothing more than a dune buggy on a cordoned-off street but it’s headed for trouble. A jumble of sawhorses and traffic’ cones simulates a road crew working over a manhole and the driverless car has to make a decision — obey the law against crossing a double-yellow line or break the law and spare the crew. It splits the difference, veering at the last moment and nearly colliding with the cones.
 “I imagine that wasn’t the most comfortable experience for you,” Chris Gerdes, a boyish and bespectacled Stanford engineering professor, calls out to the slightly shaken passenger in the car.