How will driverless cars ‘talk’ to pedestrians? Waymo has a few ideas

For years, developers have been working on ways for self-driving cars to communicate their intentions to other road users, either through audio recordings or visual cues. Today, Waymo says it wants to be one of the first companies to put some of these methods into practice.

The Alphabet-owned company’s Jaguar I-Pace autonomous vehicles will use their domed roofs, which are wrapped in LED screens, to communicate messages to other road users. For now, the company only uses two messages: for pedestrians in front of the vehicle, changing gray and white rectangles intended to communicate that the vehicle is yielding to them, and for drivers behind the vehicle, a yellow pedestrian symbol to Let them know there is a pedestrian crossing.

The symbols join other visual and audio signals that Waymo uses to “talk” to other road users. The company has used the roof dome to display the initials of the customer requesting the trip and to signal to cyclists that a passenger tries to open the door. Waymo also uses external audio alerts to communicate with emergency services or to explain what the vehicle is going to do next, such as rerouting.

Waymo calls these recordings and signals “tertiary communication.” Human drivers have become pretty good at communicating their intentions to the people around them: a small wave of the hand, a nod of the head, maybe some eye contact. And, if all else fails, we can lean on our horns or roll down the windows and say what we think (sometimes in colorful ways). Waymo vehicles have no hands or eyes to communicate with, so new methods had to be invented.

The most challenging thing was figuring out how to present them so they didn’t seem like they were telling other people what to do, said Orlee Smith, senior product manager at Waymo. After all, Waymo didn’t want its driverless vehicles to take on the role of traffic cop, barking orders at pedestrians or trying to intimidate other drivers.

“We need to create a way for someone to say, ‘Okay, I know what Waymo is doing, that Waymo is giving in, it’s not going to work right now,’” Smith said. “And as the driver behind this car, ‘This Waymo is stopped because he’s yielding to a pedestrian.’ So that was one of our big challenges.”

For now, the roof domes will only display pedestrian yield symbols for road users at the front and rear of the vehicle. Waymo plans to roll it out in San Francisco, followed by Phoenix and then Los Angeles. And since all Waymo vehicles are equipped with LED displays on their domes, the possibility of integrating future messages is almost certain.

For years, AV developers have been wrestling with the problem of how best to communicate with other road users. Uber (back when it still thought it would build its own self-driving cars) took a maximalist approach, putting flashing turn signals on the side mirrors, doors, roof, and basically anywhere there was a little bit of clearance on the road. vehicle. Drive.ai, a now-defunct audiovisual startup, was more subtle in its approach, relying on LED signs that use text and emoji-like images to communicate.

While still housed in Google’s Other types of notifications sounded stranger, such as “a robotic hand for making gestures or robotic eyes on the vehicle that allow the pedestrian to recognize that the vehicle ‘sees’ the pedestrian.”

But even though it’s been talked about for years, only one AV operator has actually brought these features into the fleet so far. Meanwhile, Waymo and other self-driving vehicles have been involved in a handful of accidents and other incidents, especially in San Francisco, that have angered emergency services and irritated residents. Better communication wouldn’t solve all of these problems, but it could have been helpful in some of them, such as when a self-driving car stops in the middle of the road.

Orlee said it took Waymo years to research this issue because it wanted to make sure it got it right. The company began studying various communication methods in 2019 and only started arriving at available solutions this year.

But if Waymo starts using its own symbols, and then rival robotaxi companies like Cruise, Zoox and Motional come up with completely different symbols, we could quickly reach a situation where multiple autonomous vehicles each display their own personalized messages to pedestrians. and other drivers. In other words, epistemological chaos.

Orlee said Waymo supports standardizing light patterns, sounds and symbols across the industry to avoid this potentially confusing scenario. She said Waymo hopes to lead that conversation, but of course other companies have their own ideas. For example, before closing, Argo AI urged other companies to adopt its technical guidelines for safe interactions between robotaxis and cyclists.

Ultimately, the onus will fall on all of us—pedestrians, cyclists, and other drivers—to figure out what these eyeless, handleless, mouthless, humanless cars are trying to tell us. And that could take some time, depending on how clear and universal the communication method is. “This will be a learned signal,” Smith said. “This isn’t something that when you first see it, you’re like, ‘Oh, I know exactly what that means,’ right?”

And of course, if all else fails, Waymo cars can still honk.