The Optical Fiber Sensor That Measures The On-line Vibration Of The Vehicle Bearing

In pace with the steady speedup of railway transportation detecting and diagnosing the vehicle on-line and assuring the safety of the vehicle are currently the concerning problem. And it has been shown that the faults mostly concern with the vehicle bearing. Therefore,in the research of detecting and diagnosing the rolling bearing of the high-speed vehicle,there is of active current and theoretical significance.In the basis of abundant firsthand investigation and theory analysis a new type of optical fiber acceleration sensor system is put forward. The working principles are as follows:when the factors of the second order mechanics model are proper,the relative displacement,body to shell,is linear to the acceleration of shell. So the acceleration of the second order system is measured by measuring the relative displacement with the optical reflection displacement theory.The paper analyzes in detail the mechanics and optics theory. In the light of the characteristic of the intensity modulation optical fiber sensor,the reference-way is presented to compensate the error signals which are caused by the bias light,dark current of photoelectric detector,temperature drift of pre-amplifier. A circuit of weak signal disposal is designed in accordance with the system characteristic.In the basis of abundant theory analysis,the object model is completed. From the initial test the sensor structure is proved to be effective.This new type of sensor model enriches the researches of optical fiber acceleration sensor and presents a new conception to the detecting and diagnosing the high vehicle on-line. So the further improvement should be made in the practice and theory.