SIEMENS road traffic data systems
SIEMENS AG
Assessing the traffic situation in a road network requires a detailed analysis of the development and distribution of the traffic. In turn, this information is needed by traffic management systems. The following parameters are recorded from the moving traffic using traffic detectors: Number of vehicles, speed, road capacity utilization and classification into cars and larger vehicles such as trucks.
TEU (Traffic Eye Universal) from SIEMENS is a system for recording traffic data which does not require cables for external power or data connections. TEU traffic detectors are fitted within urban areas and on highways to existing masts or road bridges as part of a traffic management system. The power supply consists of a solar panel and battery. Data transfer to the traffic control centre takes place wirelessly through the GSM mobile data network.
Interfacing the TEU detectors (Traffic Eye Universal)
Because TEU detectors do not need any connecting cables, installation costs can be reduced significantly compared to conventional detector systems. However, a system without cables places high demands on reliable data transfer.
SIEMENS AG commissioned INSIDE M2M to supply the GSM data transfer system because the latter company already has many years of experience with comparable M2M projects.
The chosen solution uses our well-proven product M2MGate to handle data transfer through the GSM mobile data network. Each TEU is connected via the RS485 bus to an intelligent GPRS terminal.
M2MGate with customer-specific features
A project-specific application was developed on the basis of our product M2MGate to connect the TEU traffic detectors. In defined intervals it interrogates all connected detectors and reads the recorded traffic data (length and speed of passing vehicles).
In order to reduce the volume of data which is transferred, the data is pre-processed in the GPRS terminals and key statistical parameters are determined. The statistical parameters are then sent from the GPRS terminal to a central server (M2MGate Server) which puts the data in a database and transfers it to the Siemens road traffic management system through an interface.
In addition, the GPRS terminal interrogates the solar-powered battery charger at regular intervals to get information on the current battery charge level of the TEU traffic detectors. The GPRS terminal enters a power saving mode if the battery charge level is low to ensure that the batteries can be recharged by the solar panel before they reach the state of deep discharge.
