FIBER OPTIC MICROBEND SENSOR FOR DETECTION OF DYNAMIC FLUID PRESSURE AT GEAR INTERFACES

An intensity-based microbend fiber optic pressure sensor has been developed and tested that is capable of detecting the dynamic fluid pressure between spinning gears. The microbend response of various fibers was measured in order to select the best fiber for the application and to determine the optimum deformer periodicity. The sensing fiber was embedded into the root of a modified gear, using a deformer method based on the compression of silicone rubber under pressure. Embedded gear sensors were calibrated under static pressure to 100 psi, yielding consistent results with different sensors. Gearbox tests demonstrated successful detection of dynamic fluid pressures at gear interfaces, and the ability to perform in a highly rugged environment.