Sitraffic Stella from Siemens Mobility is a new roadway station unit in the form of a compact, autonomous traffic control solution. Stella is used for weather detection, warning against icy roads, wind and fog. It can also generate speed and traffic jam warnings. The system can act independently and cause traffic lights to change in accordance with the specific situation. The roadway station unit does not have to be connected to a traffic control center.

Traffic control installations on freeways provide warnings against traffic jams, ice on the road and fog. Due to the display of recommended speeds, the traffic flows more smoothly and the traffic throughput rate increases even during critical periods. The risks of traffic jams and accident hazards are thus reduced considerably. Roadway station units collect traffic and related data, and determine what is shown on the display of the variable message signs located along highways.

Sitraffic Stella from Siemens is a solution for users who intend to gradually build up some traffic management but do not immediately want a fully equipped traffic guidance system. Given that the roadway station units can be integrated into existing installations, customers with smaller systems are able to acquire some experience first before expanding their technical equipment at a later date when necessary.

In its function as a weather station, Sitraffic Stella provides the data needed for efficient, weather-related traffic guidance. Stella can be configured: from a simple fog warning system to a complete weather station. Environmental data sensors for measuring wind, precipitation, visibility, road condition, humidity and temperature can all be connected. The station is used in places which are problematic in terms of traffic in order to put out specific hazard alarms and thus increase safety and prevent accidents in these areas.

If overhead detectors are linked up, traffic data such as speed, vehicle classification or the number of vehicles can be measured. This means that Stella can be used as a counting station or traffic jam warning system.

In addition to all this, Stella allows variable traffic signs to be connected. Triggered by events such as a traffic jam, fog or strong winds, appropriate warnings can be given to the road users locally.

The compact design and the use of a battery as an uninterruptible power supply (UPS) make it possible to integrate the control module, the power supply and communications in a single housing. Depending on the equipment, different housing types are available. Stella consists of only a few components, which can be quickly installed and is therefore suitable for temporary uses as well. Power supply by means of a fuel cell or with solar power is another way of being independent of access to power grids. Connection to the night-time power supply of a street lamp not only lowers costs for separate infrastructure but also reduces the installation time. Interfaces for data communications include cable as well as radio links such as WLAN, ISM, GSM or GPRS.

Sitraffic Stella satisfies all aspects of the requirements stipulated by TLS 2002 (Technical Delivery Conditions for Roadway Stations) and has been tested in accordance with the CE standards currently applicable in Europe. Stella is based on the Siemens SST4 family of roadside stations, which are being used successfully in many different countries all over the world.

This press release is supplemented by a photo which you can view in the Internet at:
http://www.siemens.com/mobility-bilder/MO2008020120

Further information on intelligent traffic control systems from Siemens Mobility at http://www.siemens.com/traffic