Should cars talk? Silicon Valley seeks to teach self-driving vehicles.

Many of the greatest minds in tech are working on self-driving cars that can travel safely on the road. But some say they will never be ready for the highway until they learn to talk – not just to its own passengers but pedestrians and other drivers.

A growing number of researchers are shifting their expectations of self-driving cars to include a language of signs, phrases, or emojis to replace the honking, nodding, and waving of a human driver. 

Self-driving cars need to "speak our language," or at least something similar, to become acceptable members of society, said Carol Reiley, co-founder of a Silicon Valley start-up devoted to the autonomous car's "brain."  

"My interest in robotics lies in where technology intersects with humanity," Ms. Reiley, president of Drive.ai, told Verge. "How do these cars actually interact with people?"

She is trying to tackle one of the toughest challenges to self-driving vehicles so far – user mistrust. A March study by AAA showed 75 percent of Americans fear the driverless cars, and only 20 percent are interested in trying one out. In fact, 39 percent of Americans don't want any autonomous features on the family car, including automated braking, adaptive cruise control, and lane-keeping assist. Half of this group said they know too little about such features, wrote Richard Read on The Car Connection:

AAA's findings jibe with other studies we've seen, and frankly, they're not especially surprising. Given how much trouble our laptops, desktops, smartphones, and tablets can give us, the idea of putting our lives in the hands of a computer on wheels traveling at 70 mph isn't exactly comforting. It's a big change, and it'll take some time to get used to. (News of the first accident blamed partially on an autonomous car isn't soothing anyone's nerves.)

Drive.ai is not the only team trying to tackle this challenge using better communication. Google has already filed a patent for its communication system, which flashes messages to pedestrians at crosswalks, Business Insider reported.

BMW also has a concept car with limited autonomous driving. While driving on its own, the car uses augmented reality to project its status and plans across the windshield, communicating with both the other drivers on the road and sidewalk traffic, Tech Insider reported. This lets the car tell pedestrians waiting to cross that they are safe to go. 

Reiley's idea is to partner with members of the auto industry to get language-conscious cars on the road as soon as possible.

“So much of driving is non-verbal communication, when you’re inside the car, you’ve made eye contact with other drivers and pedestrians, you wave people across, you’ve given head nods, you’ve honked at them,” Reiley told Tech Crunch. “All these types of things are ways that a human expresses what the driver’s trying to do to communicate with other drivers on the road. So now if you take the driver out of the driver’s seat and no one’s watching the road, how do all the other people around the self-driving car now know what the car is trying to do?”

Drive.ai aims to retrofit cars with a communications system of rooftop signs and beeps, which she says can not only equal but exceed the present state of communication on the road.

"The horn is one of the worst designed features on the car," Reiley told Verge, as the horn maintains the same pitch and volume whether warning of an impending collision or expressing support for a "Honk for Jesus" bumper sticker. She aims to create a beep system with, among other things, "more socially appropriate" honk alternatives.