Skip to Content

How Do You Know An Autonomous Vehicle Has Seen You?

MIT’s Media Lab demonstrates a system that lets driverless vehicles communicate with pedestrians.
April 26, 2012

The Media Lab seems to have solved a problem that we don’t yet have.

Suppose it’s the future, and you are walking along a busy street. You pass a quaint shop or two, and decide to cross the street to get to a coffee (I was going to say to visit bookstore, but of course those probably won’t be around by the time this problem arises).

Swiveling headlights and directional speakers (black cans in the middle) allow this autonomous vehicle prototype to communicate with pedestrians.

You step off the curb, look to your left, and there is a car coming toward you without a driver—one of the many autonomous vehicles that seem to be appearing in trendy neighborhoods. It slows down and stops at the intersection.

Do you dare step out in front of it to cross the street? Does it know you are there? Or will it suddenly accelerate and break your legs? There’s no driver to make eye-contact with.

A group led by Kent Larsen at the Media Lab has a solution. The researchers have outfitted a prototype electric vehicle (it’s about the size of a desk) with lights that look like eyes and the sensors from an X-Box 360 Kinect. The lights swivel to look at you when the sensors detect you, and blue LEDs flash to indicate the car has seen you. Directional speakers swivel toward you, too, and the car tells you it’s safe to cross. The system can also flash bright white LEDs to get your attention. 

Sonar sensors can detect if a pedestrian is too close to the side of the car. If they do, LEDs in the wheels to turn from green to orange and red—getting redder as you get closer—to warn you, and let you know the car knows you are there.

Just a few years ago, the possibility of autonomous vehicles driving themselves around seemed remote. It would require massive infrastructure, new laws, and completely changing driver’s minds about how reliable robotic cars could be. But now Google is testing driverless cars, and automakers are steadily adding features that allow drivers to opt out of more driving. Adaptive cruise control has taken over braking and acceleration, even in some mid-range cost vehicles. Next year, BMW will sell a car that can drive itself at speeds under 25 miles per hour.

A researcher puts his hand close to a sonar sensor, causing LEDs in a wheel to turn orange.

Autonomous vehicles seem far more plausible now. But it will probably be many years before municipalities allow them to drive around in cities. They’ll at the least require that a driver is behind the wheel in case the car goes berserk and decides to mow down a  latte-bearing pedestrians.

Keep Reading

Most Popular

Large language models can do jaw-dropping things. But nobody knows exactly why.

And that's a problem. Figuring it out is one of the biggest scientific puzzles of our time and a crucial step towards controlling more powerful future models.

The problem with plug-in hybrids? Their drivers.

Plug-in hybrids are often sold as a transition to EVs, but new data from Europe shows we’re still underestimating the emissions they produce.

Google DeepMind’s new generative model makes Super Mario–like games from scratch

Genie learns how to control games by watching hours and hours of video. It could help train next-gen robots too.

How scientists traced a mysterious covid case back to six toilets

When wastewater surveillance turns into a hunt for a single infected individual, the ethics get tricky.

Stay connected

Illustration by Rose Wong

Get the latest updates from
MIT Technology Review

Discover special offers, top stories, upcoming events, and more.

Thank you for submitting your email!

Explore more newsletters

It looks like something went wrong.

We’re having trouble saving your preferences. Try refreshing this page and updating them one more time. If you continue to get this message, reach out to us at with a list of newsletters you’d like to receive.