A Differential Light Intensity-Modulation Optical Fiber Bundles Designed for Milling Tool Vibration Measurement

Tool vibration occurs widely in various machining operations and is one of the main factors affecting machining quality and stability. Light intensity-modulation optical fiber displacement sensor has distinctive advantages and greatly potential in tool vibration measurement. In order to overcome the shortages of conventional reflective light intensity modulation fiber bundle in small measurement range or low sensitivity, a novel differential light-intensity optical fiber bundles were proposed for measuring the high-speed milling tool vibration displacement. The mathematical model was demonstrated based on differential light-intensity modulation principle for sensing characteristics analyzing in this paper, firstly; then, the static calibration platform and the dynamic experiment platform were established to verify the differential light intensity-modulation characteristic of the fiber bundles; in the end, the static calibration experiment results shown that the measurement range of the differential light-intensity fiber bundles is more than 2mm, which expanded the measurement range of conventional fiber bundle by two times while improving the sensitivity obviously. The dynamic experimental results confirm the operating principle of differential light-intensity optical fiber bundles well. It has greatly availability applied for on-line precision measurement of tool vibration in milling machines.