Repeatability of vibration-based damage detection on rolling element bearings with FBG sensors

Current state-of-the-art condition monitoring techniques for rolling element bearings, such as accelerometers and microphone arrays, face limitations in sensor placement and susceptibility to electromagnetic interference (EMI). This study addresses these challenges by employing fiber Bragg grating (FBG) sensors, which offer high sensitivity and immunity to EMI, for real-time monitoring of vibration signals directly on the stationary and rotating parts of the bearings. We created 0.5 mm micromachined damage on the outer raceway to simulate early-stage faults and assessed the probability of detection by performing repeated measurements. Our results show that FBG sensors can accurately detect and locate faults at early stages, with clear differences in damage indicators (DI) between healthy and faulty bearings, although large uncertainties in the detection of faulty signals limit the probability of detection. By enabling more precise fault location and improving diagnostic capabilities, this approach has the potential to enhance operational efficiency, safety, and cost savings in industrial applications with and prototyping of rotating equipment.