Time to green

Friday evening on the famous Las Vegas Strip. A steady stream of traffic flows along Las Vegas Boulevard. Six lanes moving north to south meet up with ten lanes of close-packed, east-west traffic on the busy West Sahara Avenue. It’s a recipe for a lot of stress behind the wheel—or so you’d think. But a small yet conspicuous display in the Audi Q7’s Audi virtual cockpit makes the stop-and-go drive through the city a little more relaxing. As the car approaches the intersection, a red traffic light symbol and a “time-to-green” countdown appear in the digital display. It reads 68, 67, 66 seconds: That’s how long it will be before the traffic light ahead turns green. So step off the gas and roll slowly toward the junction. At the next intersection, it’s a mere 32 seconds before the red signal switches punctually to green.

Welcome to the world of car-to-x technologies, where connected smart mobility is gradually becoming a reality. Late last year, Audi became the first carmaker to launch the first true car-to-x service,“Traffic Light Information” (TLI), in Las Vegas. Audi plans to roll out “Time-to-Green” in other U.S. cities soon. TLI marks a milestone on the road to mobile swarm intelligence, where vehicles communicate with the city and each other to optimize important details such as journey time, route guidance, fuel consumption and even parking space availability—all in real time.

As unremarkable as the red traffic light symbol on the display seems: A trial on the streets of Las Vegas, a city with a population of two million that attracts more than 40 million tourists each year, soon makes you realize that the connected world now extends to road traffic as well.

Equipped with this knowledge, the drive through Las Vegas is much more agreeable—like waiting for an elevator, seeing what floor it’s currently at and knowing exactly when you’ll be picked up. Initial experience shows that if you can see when a light will turn green, your journey is much more relaxing. Relaxation in road traffic is about more than just comfort. If you’re relaxed and less stressed, you drive more safely. Cars communicating with the infrastructure around them can also cut fuel consumption in urban traffic by up to 15 percent, accor­ding to forecasts.

Las Vegas has around 1,300 traffic lights. So far, 1,100 of them transmit information about their timing. Audi is the first manufacturer to process this information in the IT backend. Oregon-based company Traffic Technology Services (TTS) compares raw data from the traffic lights with historical data, checks it for statistical reliability and sends it in real time to the on-board computer via LTE, provided the connect PRIME service is enabled. This works in the U.S. with all current Audi Q7 and Audi A4 models fitted with Audi connect. Every vehicle crossing a traffic light intersection in Las Vegas contributes to improving the system and the quality of the forecast, meaning the “Time-to-Green” service can be continuously enhanced. This is no easy task. Multilane intersections have complex traffic light timing systems that have to take into account, say, two left-turn lanes and hundreds of pedestrians.

As the first city to offer a traffic light countdown, Las Vegas sees itself as a pioneer in smart mobility that transmits infrastructure data to individual vehicles without any time lag. “I realized during the first demonstration how important traffic light info can be for the driver. It has an immediate, positive impact on how you drive,” says Dan Langford, executive director of the Nevada Center for Advanced Mobility (NCAM). NCAM is a central organization geared to driving forward smart mobility projects. “It looks simple because it just works, but it’s quite a technical accomplishment.” Software on board the vehicle and in the cloud is already capable of learning from a driver’s behavior and from a constant influx of infrastructure data such as traffic light timings. Going forward, a car will be able to develop and refine its own rules for road traffic behavior and share them with other cars and external services in the context of piloted driving. Future generations of autonomous vehicles will be able to “see” their surroundings without having to identify traffic lights visually like a human driver.

Audi is also actively involved in urban planning in Somerville near Boston, Massachusetts. Together with the city and local real estate developers, the four rings are working on building intelligent technologies and services into an integrated mobility system. For example, using car-to-x communication, traffic flows in cities could be improved—or, thanks to piloted parking, the space required for personal mobility could be reduced.