One afternoon last month, as I was crossing a busy four-lane street that runs through the University of Pittsburgh campus, I looked up to see a robot blocking my path.
This wasn’t unexpected. Over the summer, several four-wheeled, knee-high robots had been roaming campus, unmarked and usually with a human handler several feet behind. Recently they’d multiplied, and now they were flying solo. They belonged to Starship Technologies, I learned, an autonomous delivery service rolling out on college campuses across America.
