The experiment convinced the engineers that it might not be possible to have a human driver quickly snap back to “situational awareness,” the reflexive response required for a person to handle a split-second crisis.
.. So Google engineers chose another route, taking the human driver completely out of the loop. They created a fleet of cars without brake pedals, accelerators or steering wheels, and designed to travel no faster than 25 miles an hour.
.. At the soonest, Google says it hopes to put such vehicles on the market by 2019.
.. Significantly, Toyota, the world’s largest carmaker, has not joined the rush to self-driving. It has established a research laboratory in Palo Alto, Calif., that does not aim to make a car that drives itself, but instead a “guardian angel” — a computerized system that would take over only when the human driver made an error.
.. Automotive engineers at work on autonomous vehicles refer to a design challenge they call “overtrust,” the possibility that humans may not fully understand the limitations of the self-driving safety features they rely on.
.. “Beta products shouldn’t have such life-and-death consequences,” said Steve Wozniak, co-founder of Apple, who owns a Tesla Model S.