Exploration of Using FBG Sensor for Axle Counter in Railway Engineering

Fibre Bragg Grating (FBG) sensors are finding increasing applications in smart structures. They can be embedded in civil structures such as bridges, buildings etc for the detection and monitoring of parameters such as strain, pressure and temperature. It allows assessments on the integrity of structures at various manufacturing and construction stages, and facilitates health management of many important structures in their subsequent operations. However, their application in railway engineering is rare. This paper explores the technical feasibility and potential usage of FBG sensor for axle counter application in railway engineering. In essence, an axle counter system is used for counting the number of train axles coming in and out of a section of rail track. Field tests have been carried out and concluded that FBG is having great potential for replacing conventional railway axle counter system, which is based on the principles of magnetic field disturbance technology as the wheels are passing by. FBG axle counter have lots of advantages over their conventional counterparts due to its electrical immunity to noise, multiplexing capability, compactness and more importantly, its relatively low cost of construction. Provided there is a weather proof and robust mounting methodology in the next phase, the FBG axle counter will become a strong competitor to conventional systems. Once the physical integrity of FBG systems is proven to be satisfactorily, one can extend its application to build a smart railway, particularly as part of a new generation of signaling systems. Key-Words : Fibre Bragg Grating, Axle Counter, Train Detection & Identification