Can your car tell you when the light's about to change?

An Audi connect-equipped A6 cruises on the Las Vegas strip.
An Audi connect-equipped A6 cruises on the Las Vegas strip.
(Courtesy of Audi AG)

Traffic lights are so tedious, right? You have to know they're there, pay attention to what color they are and know what the colors mean, when all you really want to do is hack your car's entertainment system so you can watch Netflix while you drive. I mean, come on.

Well, sigh no more wannabe inattentive drivers! Audi is working on Project Traffic Light Online, which uses the Audi connect Online system to read the signals from a city's central traffic computer. If a green light is going to turn red, Audi's system will let you know with a message in the instrument cluster display that's located between those pesky dials that tell you, like, how fast you're going and how fast the engine is turning. Who even uses that information?

The system will also know when a red light is about to turn green, so it can fire up the engine a few seconds early to make start-stop tech even easier for drivers to use. And it will even calculate if you can make that stale green light; if not, it warns you to use the brakes. It won't actually break for you, but it will strongly suggest that you get on that.

Of course, all of that data isn't just floating in the air for anyone to use. Audi has a Project Traffic Light Online test car that's driving around Las Vegas right now, and they had to get permission from the Regional Transportation Commission of Southern Nevada to tap into the data. Luckily, Nevada is already on board with driverless cars being tested in the state, so this probably wasn't a big leap for the RTCSNV. But, as Audi electronics engineer Michael Zweck noted, "For a nationwide rollout, we will have to contact more than 500 independent agencies." Not to mention that as of right now, the format of the data hasn't been standardized.

A Couple of Reasons Why This Might Matter

Traffic light information is displayed on Audi's Driver Information System (DIS) located in the vehicle's central instrument cluster.
Traffic light information is displayed on Audi's Driver Information System (DIS) located in the vehicle's central instrument cluster.
(Courtesy of Audi AG)

Beyond helping those drivers who simply cannot be bothered to notice the most basic traffic information to avoid running over pedestrians at every intersection, there are some practical advantages of Project Traffic Light Online, too. First, it helps save gas. Starting and stopping the vehicle sucks up gas, while cruising along at a steady speed, whether that's 25 miles per hour (40.2 kilometers per hour) or 65 miles per hour (104.6 kilometers per hour), uses less fuel. So Audi's system, according to Zweck, "recommends an optimal speed within reasonable limits to reach a green traffic light. This avoids unnecessary stops and speeding and thus improves fuel efficiency." That's engineer-speak for the system telling you that if you roll along at 32.7 miles per hour (52.6 kilometers per hour), you'll hit green lights all the way down this street. If you don't have to stop for a light or mash the gas to make the green, you use less fuel.

The second practical advantage of the system is to smooth out traffic flow. If everyone is flowing through traffic lights at optimal speed within reasonable limits, there are likely to be fewer waits at red lights and fewer fender benders that snarl up entire intersections. But if only a few Audi models are equipped with the ability to read traffic light data, won't those schmucks in the unhelpful cars muck everything up anyway? Not according to Zweck, who said, "Research suggests that improved traffic flow can be measured when 5 to 10 percent of all vehicles are equipped with this technology." That's still a lot of cars. In 2013, there were nearly 250 million cars on the road, which means 12.5 million cars, at a minimum, would have to be talking to the traffic signals.

While this is another step toward the driverless cars of the future we've been hearing so much about, Zweck noted that Project Traffic Light Online was developed independently of Audi's self-driving A6 Avant, which was at the 2013 Consumer Electronics Show. There are a couple of test cars in a small handful of cities worldwide, but there's no projected on-sale date for red-light reading Audis yet.

Author's Note: Can your car tell you when the light's about to change?

I have an uncle who, when I was a kid, timed all the lights along a nearby city's main drag. He calculated the optimal speed for making every green light in this long string of traffic signals. He would express dismay -- but never outrage -- at drivers who were unaware of this optimal speed and travelled too slowly by a couple miles per hour, thereby wrecking his green-light run. He would very much admire Michael Zweck and his team's work, I think. Or maybe he'd think they took all the fun and personal satisfaction out of figuring it out.

In any case, Audi and Zweck make a convincing case for smoothing out the traffic flow. I can't count the number of times some idiot who was definitely not me thought she could make a green light if she sped up, only to realize she could not make it and, after checking the rear view to make sure there wasn't anyone too close to her bumper, engaging the always helpful ABS. But that was very much not me. At all.

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  • Edelstein, Stephen. "Audi Traffic Light Recognition Could Save Time and Fuel." Popular Science. March 12, 2014. (March 26, 2014)
  • Experian Automotive. "Total number of vehicles on the road reaches highest level since 2008." PR Newswire. Nov. 4, 2013. (April 3, 2014)
  • New York Daily News. "Audi shows off self-driving A6 Avant and RS7 Sportback." Jan. 28, 2013. (March 26, 2014)
  • Zweck, Michael. Audi electronics engineer. E-mail interview conducted on April 2, 2014.