Going left the right way:
Vehicles improve turning skills at tricky intersection
The future of self-driving cars could depend, in part, on a Mesa intersection. Some tricky situations at South Longmore and West Southern Avenue are being used by Waymo to “teach” autonomous vehicles how to navigate some difficult left turns.
Waymo has been “teaching” its autonomous vehicles how to navigate difficult left-hand turns based on a tricky Mesa intersection.
James Stout, a lead software engineer for Waymo, the self-driving car project from Google’s parent company Alphabet Inc., explained the tests in a blog posted Thursday.
The Mesa intersection of South Longmore and West Southern Avenue uses a
flashing yellow arrow to indicate to drivers they can make a left turn when traffic is clear, he said. Common in metro Phoenix, flashing yellow turn signals are not used around the company’s headquarters in Mountain View, California.
Waymo brought test vehicles to the Chandler-Mesa area last year, and earlier this year began offering free rides around town to certain families who apply through the company website.
The test drivers who operate Waymo cars would retake manual control at this intersection, as they do in all instances when they feel it is the safest maneuver. The cars have been getting better at guiding themselves through tricky situations, but are not perfect.
“This type of intersection can be tricky for humans and self-driving cars alike,” Stout wrote.
Rather than run self-driving cars through the intersection — or others like it — repeatedly in real life, Waymo created a virtual computer world where the self-driving cars can practice the intersection with different cars, pedestrians, cyclists and other challenges.
“Think of this simulation as a ‘Matrix’ world we’ve designed for our self-driving cars,” Stout said. “In doing that, we are able to get far more experience than we could get just driving alone.”
Google has as many as 25,000 cars operating in simulated environments and they can gain 8 million miles of driving experience a day. That experience is added to the collective knowledge of the software making decisions in the cars on the road.
“Just like for human drivers, the key to learning is practice,” Stout wrote.
The simulators also allow the cars operating in the Phoenix area and other cities to run smoothly while they are conducting on-road tests.