Vibration monitoring with a Silicon micro-fabricated device coupled to an optical fiber

We developed a micro-fabricated structure embedded to an optical fiber, which combination integrates a vibration sensing monitoring device, including sensing in high electromagnetic media. The micro-machined structure uses a combination of mass structures coupled to a centered mirror through springs, all Silicon-based and assembled in front of an optical fiber for motion interrogation using interferometry techniques. We present the design and fabrication steps of two different size and shapes of the micro-fabricated devices, along with their resulting resonant frequencies, and optical characterization. The results show that devices have potential for vibration monitoring including applications for high electromagnetic power generation machines such as big motors and transformers, as well as integration into condition-monitoring equipment.