“I’m not surprised,” said Chris Hendrickson, professor emeritus in civil engineering and director of the Traffic21 Institute at Carnegie Mellon University. “Autonomous vehicles aren’t that common yet. It’s a disruptive technology until people get used to it.”

Raj Rajkumar, co-director of CMU’s General Motors Connected and Autonomous Driving Collaborative Research Laboratory  said it took five to 10 years for the public to accept relatively simple technology advancements such as cruise control when it was introduced in the late 1980s. The technology of self-driving vehicles, which can communicate with each other and a central transportation computer system to keep passengers safe, is far more complicated, he said. “The technology has to mature. It’s going to take a longer time to shake things out and get public acceptance,” he said.