Failure Mechanism Analysis and Experiment of MEMS VRG under High-g Shock

This paper investigates the structure response and failure mechanism of a micro-electromechanical system (MEMS) vibrating ring gyroscope (VRG) under high-g shock. A principle for categorizing different types of loading shock according to the VRG’s frequency scales is devised. A dynamic response model of the VRG structure to diverse types of shock based on quasi-static, vibration and elastic wave theories is established. The failure mechanism of the VRG is analyzed for the typical failures of MEMS devices, including pull-in, fracture and delamination. Based on the established dynamic response model, the inertial displacement that leads to pull-in failure, the fracture-sensitive positions of the VRG structure under different shocks, and the physical model of delamination failure under shock are derived. Through the shock experiments, the critical amplitudes of the loading shock that cause the failures of the VRG are obtained, the reliability model of the VRG under high-g shock is established, and the model established by analyzing the failure mechanism of the VRG is verified from the results of the experiments.