(c) wien.gv.at

Traffic lights are a key factor for a smooth traffic flow. In the future, traffic lights with pedestrian recognition and a holistically interconnected traffic light system will help to make traffic smoother and more efficient in Vienna. Additionally, through weather and environmental sensors that are mounted to Viennese traffic lights, a dense grid of measuring stations is formed, which provide valuable data for diverse applications.

Traffic lights equipped with a camera system are to reduce the waiting time for pedestrians in the future. This system is being tested since May 2017 at an unknown intersection in the tenth district of Vienna – this is to ensure that pedestrians behave naturally and the results are not deliberately falsified. In case of a positive test result, the technology should replace traffic light systems with push buttons in the long run.

Algorithms recognise desire to cross

The system developed by the TU Graz and the municipal department 33 (Public Lighting) differs significantly from a simple motion sensor. While such a system would switch to green even when any other object would pass it, the traffic light camera detects not only people but also whether there is a desire to cross or not. “This system can detect if a person actually wants to cross the road or if he/she has actually nothing to do with the traffic light,” says Walter Mimmler from the municipal department 33. The new traffic lights have the purpose of reducing unnecessarily long waiting times and thus improve the comfort of pedestrians.

Strict framework conditions during the test phase

With the traffic light camera in Vienna Favoriten the reliability of the technology is tested. The system may fail a maximum of 50 times in a sample of 10,000 pedestrians. If the tests stay within these numbers, nothing stands in the way of a more extensive implementation from spring 2018 on. With costs of around € 5,000, the new system, according to Walter Mimmler, is just as expensive as conventional pedestrian traffic lights with push buttons.

Interconnected traffic lights

In addition to traffic lights with pedestrian recognition, there are also efforts in the City of Vienna to make the traffic light system as a whole smarter and more flexible. This is to be achieved by interconnecting all traffic lights. This allows individual traffic lights to communicate with each other and to resolve unpredictable traffic jams caused by accidents or construction sites quicker. Traffic light phases can thus adapt to the actual traffic situation, thereby improving the traffic flow and reducing emissions.

Integration in navigation systems

The traffic lights should not only communicate with each other, but also pass on valuable traffic-related information to smartphones and navigation devices. With this information, these could in turn calculate at what speed a car has to move around in order to having to stop at red traffic lights as rarely as possible. Corresponding street signs along certain routes could also specify the pace for the green wave. “With this traffic light we would for example have the opportunity to create a green wave at 40 km/h in order to naturally avoid congestion. That’s what a modern metropolis like Vienna needs. I think this is a good investment in our future,” says Maria Vassilakou, Executive City Councillor for Traffic & Transport.

Weather and environmental sensors

In cooperation with the Central Institute for Meteorology and Geodynamics (ZAMG), the traffic lights in Vienna will be equipped with around 10,000 weather and environmental sensors over the next few years. This enables a multitude of applications using “big data analytics”. For example, heat islands can be detected or air quality can be improved through intelligent traffic flow control. The aim is to equip all traffic lights in Vienna with high-quality sensors that are able to directly transfer the data to an online tool for analysis. In the first expansion stage, sensors for measuring temperature and humidity are planned. At a later stage sensors for nitrogen oxide, sulfur oxide and noise will follw. According to ZAMG the system is sustainable and designed in a way that any kind of sensors can be connected. The measurements will provide enormous amounts of data every day. High-performance computers and methods from artificial intelligence and machine learning will analyse and process this data. Using big data analytics patterns and correlations can be identified and used for practical applications.


Municipal Department 33 – Public Lighting

E-Mail: post@ma33.wien.gv.at

Website: Municipal Department 33 – Traffic Lights

This post is also available in: German