Diagnosis without Sensors: Integration of External Data for Condition Monitoring of Railway Switches

A highly available infrastructure is a premise for a capable railway operation of high quality. Therefore maintenance is necessary. Especially switches are critical because they connect different tracks and allow a train to change its moving direction without stopping. Their inspection, maintenance and repair have been identified as a cost driver for infrastructure managers. The Institute of Transportation Systems, in cooperation with the German Railways (DB AG) is exploring ways to monitor the condition of switches and their degradation process to reduce failures and thus maintenance costs. Any sensor applied in the field has to be very reliable and robust, due to the fact that switches are exposed to strong forces and sometimes extreme weather conditions. But such sensors are expensive. Hence huge investments would have to be made if the current 71 000 switches and diamond crossings of German Railways would be equipped. Therefore it is the goal of the research to determine and monitor the condition without sensors. External data sources have to be identified and integrated to provide the necessary information otherwise gained from sensors. This paper presents how an existing diagnostic system can be improved via external measured parameters to monitor the switch condition