Experimental and Analytical Investigation on a Proposed Embedded Fiber Optic Displacement Sensor

摘要

Vibration damping measurements are currently obtained using sensors that measure beam tip displacements by determining the position of the beam cross section with time. In composites, bending-twisting couplings can occur which result in the beam undergoing two dimensional vibration motion when subjected to a bending moment. A new monitoring technique was conceptualized and validated which utilizes embedded optical fibers as the sensors. This paper discusses the experimental validation of the concept, the physics involved in the optimization of the technique, and the areas in need of further development. The experiments have shown that two dimensional vibration can be detected using this technique. Actual displacement time information was not available for the specific test apparatus used and therefore damping loss factor information was not obtained. Further development of the data acquisition system and methodology for determination of the image center is required along with an appropriate grid xy sensor in order for the technique to be acceptable as a new technique for measuring the vibration damping loss factors for materials.