Avoiding Squirrels and Other Things Google’s Robot Car Can’t Do

Photo: Ariel Zambelich/WIRED

Google’s self-driving car is still at least five years away from commercialization, but the team behind the project has made remarkable progress since starting work in 2009. We took a roughly three-mile ride around Mountain View in one of the modified Lexus SUVs, and it drove so well on its own, it was kind of boring. Over 700,000 autonomous miles, the Google cars have learned a lot. They can break the speed limit to stay safe and be just aggressive enough at a four-way stop to get through the intersection.

But a lot of work remains to be done. There are lots of things the cars still can’t do, like deal with snow or avoid killing small animals.

Here’s what we found most surprising about what Google’s robot car can and can’t do right now.

Yes It Can:

• Avoid creaming cyclists: In the event a cyclist actually decides to warn traffic before he turns, the car notices. Thanks to laser imaging, the car recognizes the hand waving and will expect the cyclist to move over.
• Be aggressive: It turns out self-driving cars tend to be too polite. Google noticed that at four-way stops, the car stayed behind the stop line, waiting for its turn. Naturally, human drivers, seeing it just sitting there, took advantage and crossed ahead of it. So the team rejiggered the car to slowly inch forward at stop signs, signaling to other drivers that it wants its turn.
• Break the law: For city driving, Google keeps it legal. But on the highway, team members adjust the settings to let the car drive above the speed limit, to safely keep up with the flow of traffic.
• Pick up on potholes:Like with speed bumps, the car spots potholes and slows down before hitting them. It doesn’t drive around them, though, so owners should think about saving up for a new suspension once in a while.
• Predict the future that didn’t happen: Say the driver takes control because he isn’t confident the car will properly handle a tricky situation, like navigating construction. The car shoots all of the info its sensors are picking up, so the team can run a computer simulation of how the car would have acted if the operator had let it handle things. That means Google doesn’t have to find out the hard way it needs to tweak the car’s behavior.

No It Can’t:

• Take you to the mountains: Bad weather doesn’t just make traction control tricky, it change how the car sees the world around. Snow on the ground and water kicked up by other cars messes with the spinning laser that sits on the roof, while fog limits how far the radar can see. Fortunately, Google is doing the bulk of its testing the Bay Area, where it will get a lot of practice with fog. Ten bucks says engineers are lobbying for a trip to Tahoe–you know, for snow testing.
• Go off the grid: Like a millennial, the car gets upset when it can’t get a cell signal, which give it access to Google’s bank of detailed maps and let it send new information back home. No worries if the connection is a bit slow, but if it drops out, the car will “do something safe,” Chris Urmson, the project director, said. He didn’t elaborate, so we’ll assume the car asks the human to take over, then focuses on other mission-critical tasks like finding a good radio station.
• Understand traffic cops: The car will detect that “there’s a person standing in the middle of the road waving their hands in a funny way,” Software Lead Dmitri Dolgov said, but it won’t be able to decipher different hand motions. Rather, it will understand that something unusual is happening, and act conservatively, or ask the human at the wheel to take over.
• Avoid creaming squirrels: While the car picks up pedestrians who may jaywalk and deer that could bolt across the road, squirrels are still too small for its sensors. The team is constantly working to pick up more and more detail, but hasn’t “done a squirrel test,” Urmson said.