Localized Strain Sensing Using High Resolution, Highly-sensitive MEMS Resonant Strain Gauges

This thesis presents experimental measurements of the first-ever MEMS double ended tuning fork (DETF) resonant strain gauge for localized strain field sensing, successfully bonded to steel by rapid inductive heating. With a gauge length of just 200μm, the presentedMEMS resonant strain gauge enables a high spatial resolution sensor capable of accurately detecting localized strains better than commonly used foil strain gauges, which average strain measurements over much larger areas. The improvement in sensing of MEMS gauges over the foil gauge is demonstrated both experimentally and theoretically, and as such, the technology exhibited herein may help improve crack propagation detection, service life monitoring to prevent catastrophic failure in components like bearings and aircraft landing gear, monitoring of critical joint components in structures such as bridges and buildings, and high resolution strain detection in precision machine-tools