Whats Holding Back Self-driving Cars? Human Drivers

In just a few years, well-mannered self-driving robotaxis will share the roads with reckless, law-breaking human drivers. The prospect is causing migraines for the people developing the robotaxis.

In just a few years, well-mannered self-driving robotaxis will share the roads with reckless, law-breaking human drivers. The prospect is causing migraines for the people developing the robotaxis.

A self-driving car would be programmed to drive at the speed limit. Humans routinely exceed it by 10 to 15 mph (16 to 24 kph) - just try entering the New Jersey Turnpike at normal speed. Selfdriving cars wouldn’t dare cross a double yellow line; humans do it all the time. And then there are those odd local traffic customs to which humans quickly adapt.

In Los Angeles and other places, for instance, there’s the “California Stop,” where drivers roll through stop signs if no traffic is crossing. In Southwestern Pennsylvania, courteous drivers practice the “Pittsburgh Left,” where it’s customary to let one oncoming car turn left in front of them when a traffic light turns green. The same thing happens in Boston. During rush hours near Ann Arbor, Michigan, drivers regularly cross a double-yellow line to queue up for a left-turn onto a freeway.

“There’s an endless list of these cases where we as humans know the context, we know when to bend the rules and when to break the rules,” said Raj Rajkumar, a computer engineering professor at Carnegie Mellon University who leads the school’s autonomous car research.