Smart Self-Driving Cars Still Need to Factor in Human Error

As companies such as Google Inc., Mercedes-Benz and Volvo Cars race to develop vehicles that are smart enough to drive themselves, even the most sophisticated systems will sometimes be no match for human error.

In a recent incident, a Volvo employee trying to demonstrate safety features instead ran into a group of people. The driver thought the car was equipped with an option that detects pedestrians and brakes automatically. It wasn’t, and the way the driver gunned the XC60 sport utility vehicle might have overridden the function anyway.