Using Vehicle 2 Infrastructure technology, Audi drivers can “catch a green wave” of traffic lights.
Using Vehicle 2 Infrastructure technology, Audi drivers can “catch a green wave” of traffic lights.
Image: Supplied

Audis in Germany, provided they are fitted the Audi connect Navigation & Infotainment package and optional camera-based traffic-sign recognition, are now able to network with traffic lights in Düsseldorf, Germany.

After Audi’s home city of Ingolstadt, Düsseldorf is the second in Europe in which Audi is introducing its Traffic Light Information service.

It’s one of the new technologies championed by the German brand in efforts to minimise the time drivers spend being stationary at intersections, and also reduce emissions through improved fuel consumption by gliding through cities largely unopposed by red lights.  In a pilot project of these V2I (Vehicle 2 Infrastructure) systems, Audi says it was able to reduce fuel consumption by 15%.

With almost all intersections in Düsseldorf to be compatible with this system by mid-2020, Audi’s Traffic Light Information system works in two separate protocols: Green Light Optimised Speed Advisory (GLOSA) which provides drivers of cars fitted with this V2I info on approximate speeds required to catch the next green light (getting a “green wave”); or if stopping is unavoidable, there’s also a "Time-to-Green" countdown displaying the seconds remaining until the next green phase begins. Drivers can relax, take their foot off the throttle pedal and save fuel.

Drivers do not have to accelerate unnecessarily, they are not stressed and they drive more safely.

GLOSA can also suggest reducing speed gradually about 250 metres ahead of the traffic lights so that the driver and the cars behind reach the intersection when the lights turn to green. This reduces uneconomical stop-and-go traffic.

“With Audi Traffic Light Information we wish to improve convenience for drivers, increase traffic safety and encourage an economical style of driving that looks ahead,” says Andre Hainzlmaier, head of development for Apps, Connected Services and Smart City at Audi.

“To do this, we have to predict precisely how traffic lights will behave in the next two minutes. At the same time, exact forecasts are the biggest challenge. Most signals react variably to traffic volume and continuously adapt the intervals at which they switch between red and green.”

Audi and its project partner Traffic Technology Services have developed a complex algorithm that calculates exact predictions from three sources: from the control programme of the traffic signals; from the real-time data of the traffic computer, a combination of road-occupation cameras, detector strips in the road surface, data on approaching buses and trams, and buttons that pedestrians press; as well as from historical data.

The forecast algorithm improves itself continuously and learns how, for example, the traffic volume changes in morning commuter traffic or at midday when children leave nurseries and schools.

Audi Traffic Light Information premiered in 2016 in the US and is available at more than 10,000 intersections in North America. Audi is said to be the world’s first automotive manufacturer to network its series-production models with city traffic lights.