Off-The-Shelf MEMS for rotary MEMS

This work demonstrates the utilization of an Off-The-Shelf (OTS) MEMS accelerometer to accurately and repeatedly determine the onset of instability and perform in situ diagnostics of a high-performance rotary MEMS device. The accelerometer is shown to provide high sensitivity, wide bandwidth vibration measurements when bonded to the stator of a MEMS device. Vibration sensing is augmented with optical displacement sensors to create a multi-modal sensor platform. The sensor suite has been used to characterize the rotor instability for rotor speeds from 10-20 krpm, diagnose imbalance acceleration with sensitivity down to 0.001 g, determine rotor wobble of with an accuracy of <;500 nm, and monitor system resonances through the speed range of 5-20 krpm. The data provided by the on-chip accelerometer can be used in feedback systems to optimize device performance and increase operational lifetimes.