A new adaptive signal control system demonstrated by Siemens in the German city of Muenster has improved the flow of traffic by 30%.

Siemens installed the Sitraffic Motion traffic control system at 24 traffic signal-controlled intersections on the heavily travelled Albersloher Weg in Muenster in 2006.

The technology was used to analyse the current traffic situation on the main artery and then automatically optimise the red-green phases of the traffic signals at the 24 intersections. The result was an average 30% reduction of driver waiting times at traffic lights. Fuel consumption and exhaust emissions where also reduced.

A spokesperson for the study said that the level of improvement had been unexpectedly high.

“In view of the success of the study, which brought about a further improvement in traffic quality compared to a traffic-dependent control method, the Muenster city council has decided to equip another busy road with the new system from Siemens in a subsequent construction phase,” the spokesperson said.

Sitraffic Motion determines how many vehicles are underway, where they turn off and where there is an imminent threat of congestion by means of detectors mounted in the approach roads.

A central traffic computer then receives the data, analyses the traffic situation at the intersections along the 6km-long road in 15 to 20 minute cycles and automatically adapts the lengths of the red-green phases of the traffic signals as well as the green wave accordingly.

Siemens mobility demonstrated the Sitraffic system as part of the “green wave for Muenster” programme.

By Daniel Garrun.