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Developing DAS for rail industry use could have enhanced asset management crew management and security applications.
During the past five years, different technologies, for example fiber optic sensors using technologies such as Fiber Bragg Grating (FBG) and Distributed Acoustic Sensing (DAS) gained increasing interest within the railway industry. Several tests and trials regarding proof of concept, reliability and safety standards were performed by various railroad companies. As a leading supplier of sensor technology for railway applications, Frauscher Sensor Technology is aware of such trends and continually investigates innovative sensor technologies to improve detection and monitoring with less effort and costs. True to this basic philosophy, only DAS revealed comprehensive potential to become a base technology for various specific railway applications.
Fascinating results
Appropriate tests have been made on tracks ofTransportation Technology Center, Inc., and CSX, as well as in various countries all over the globe, such as Australia, Germany and the United Kingdom. Besides comprehensive train tracking and asset condition monitoring capabilities these projects revealed the ability of DAS-based systems to track people, monitor work groups, detect trespass, protect infrastructure and more. On that base a substantial number of applications in the areas of train tracking, asset condition monitoring and security of people and infrastructure have been carried out. Whereas the realization of complex and safety relevant applications in the fields of train tracking and asset condition monitoring still needs further development, full wayside security solutions are already available.
As a worldwide expert for sensor technologies used on railroads, Frauscher has started a comprehensive and highly focused research and development program to make DAS ready for the railway industry. This program comprises various concepts, which include starting to enhance the DAS system and to provide a rail-specific Human Machine Interface (HMI) that displays data in a proper way and enables appropriate reactions to tracked events.
Principle of DAS
The principle of DAS is based on the ability of detecting changes in intensity of light reflections caused by sound waves radiating against a single-mode fiber optic cable as shown in Figure 1. A coherent laser is pulsed into this fiber at a set frequency. Natural impurities within the fiber cause a small portion of light to be reflected back to the source, which is called...