Dynamically Amplified Dual-mass Gyroscopes with In-situ Shock Survival Mechanism

This paper reports on development of Dynamically Amplified dual-mass Gyroscope (DAG) and introduces, for the first time, a Trap-and-Hold (TAH) concept intended to increase survivability of gyroscopes to mechanical shocks and vibrations. The TAH concept utilizes out-of-plane electrodes to electrostatically excite the gyroscope's proof-mass at resonance in the direction perpendicular to the substrate, trap the proof-mass electrostatically, and then keep the sensor structure locked to the substrate during the events of shock. We discuss our fabrication process to realize the TAH mechanism and present initial experimental results. In our demonstration, the operational device measuring rotation was instantaneously immobilized by TAH before the event of shock, and was subsequently released to its normal operation after the event of shock. The device preserved its functionality and fundamental characteristics, Angle Random Walk (ARW) and in-run bias instability (IrBS), before (ARW: 0.048 deg/rt-hr, IrBS: 0.6 deg/hr) and after the experiment (ARW: 0.0483 deg/rt-hr, IrBS: 0.69 deg/hr).