Fiber Bragg Grating Sensor Based Vibration Monitiring for Foreign Matter Invasion of Protective Barrier

Abstract

A vibration monitoring system based on fiber Bragg grating is proposed to meet the need of protective barrier along the railway to monitor the foreign matter invasion. A high sensitivity fiber Bragg grating vibration sensor based on cantilever structure is developed. Three vibration sensors were deployed to a protective barrier with a length of 20 meters to conduct intrusion vibration monitoring test. Test results show that: 1) the fiber Bragg grating vibration sensor can well monitor the vibration signal; 2) the vibration intensity decreases obviously with the distance impact position increasing; 3) the response time of vibration measurement of different sensors is also in sequence when the distance impact location is different. Therefore, the magnitude of the external impact and the impact position in the protective barrier can be analyzed through the response amplitude distribution of each sensor and the response time sequence of the sensors.