The bends to the left are heavy and unprotected links – no traffic light or stop sign to show the way – are even more difficult. This applies to both human and robot drivers; even the most skilled self-driving car struggles to make a seamless left-turn.
Cruise, the self-driving division of General Motors, knows that this is true. In a recently published video, the company calls unprotected left-hand turns "one of the most difficult maneuvers" a self-driving car can perform. That is why the company has focused on perfecting these turns. Cruise & # 39; s self-driving cars & nbsp; routinely run 1,400 unprotected lefts every day in the complex environment of San Francisco, the company said.
"In an unpredictable driving environment like SF, no two unprotected left-hand turns are the same," said Kyle Vogt, Cruise & # 39; s president and chief technology officer. "By processing 1,400 regularly, we generate enough data for our engineers to analyze the lessons and include them in the code they develop for other difficult maneuvers."
Weird flex? Not really. Cruise probably feels a bit stubborn after massive, back-to-back investments from SoftBank and Honda, giving the company a post-money valuation of $ 19 billion. This may explain why Cruise feels comfortable with the release of this data point, while other self-driving companies try to hold expectations about when their cars will take to the streets.
Why are turns to the left so difficult? It is because they need self-driving cars to be both careful and assertive at the same time. The vehicle must push its front end into oncoming traffic while the sensors look for an opening between cars. Human drivers can communicate non-verbally with other drivers with the help of hand gestures or eye movements; robot cars & # 39; s do not have those benefits.
"Unprotected lefts are one of the toughest things you can do while driving," Nathaniel Fairfield, a software engineer who manages the Waymo behavior team, told Popular science earlier this year.
Waymo, one of Cruise's biggest rivals, is all too well aware of the challenge of unprotected left-hand turns. During a recent test drive, a reporter with The Washington Post reported that "turning left turns can be painfully slow" when turning on an important traffic artery. The information reported a similar problem in 2017. (I experienced an unprotected left-hand turn in Arizona last November that was not painfully slow or seamless.
In a separate article about Cruise & # 39; s bumpy ride to autonomy, The information noted that the company wanted to tackle the left-turn challenge with machine learning:
Cruise has developed an algorithm that can calculate how far it can crawl in the middle of many intersections before attempting to make a left turn. (It is another matter to successfully complete the turn.) Still, the surface of what a machine should be able to replace people scribbles.
Cruise has said it plans to launch a commercial ride farewell service in San Francisco in 2019.