Self-driving cars and Left Turns

"In a perfect world, cars and trucks would never turn left. Left turns waste time, gas, and are dangerous for drivers, oncoming traffic, and crossing pedestrians. So imagine teaching a machine to turn left - in Boston's infamous traffic, no less? A driverless car has to read human psychology - the subtle signals from other drivers and pedestrians - to navigate one of the hardest maneuvers on the road.

"As engineers race to build self-driving cars, they've found that making them safely turn left is one of their toughest problems. 'I see a lot of challenges every day, and left turns are near the top of the list,' said John Leonard, a professor at the Massachusetts Institute of Technology who specializes in self-driving vehicles.

"Left turns are so tough because they involve psychology as well as technology. Drivers and pedestrians read subtle signals from each other as they approach an intersection. We've come to learn how to read those signals to make pretty good guesses about when it is safe to turn left in a variety of traffic conditions. . . .

"But today's automated cars don't know how to read people - and people don't know how to read them. As a result, said Pratt, building cars that can safely negotiate all kinds of left turns will take years - perhaps more than a decade."

A recent Boston Globe article reported on this challenge in developing safe self-driving cars.

To access the complete Boston Globe report, please visit:

The Boston Globe: Teaching a driverless car to turn left