Simulation of Micro-Gyroscopes Dynamics

Numerical simulations were performed to find the optimal parameters (stiffness, mass and damping) for a MEMGyroscope actuated by parametric resonance. Micro-gyroscopes are micro-sensors that detect changes in system's angular rate. A 2 DOF system is subjected to the Coriolis effect and actuated by parametric resonance, was analyzed. This system is more robust since it is less sensitive to parameter variation due to fabrication imperfection. It is an improvement over previous designs because the response of conventional harmonic gyroscopes is very sensitive to parameter differences. Parametric resonance occurs when external excitation appears as a time-varying modification of a system parameter. Interdigitated combfingers were used as an actuation system where force depends on the displacement, thus the stiffness of the system varies along the motion. Matlab was used to develop numerical simulations where spring stiffness and mass parameters were changed. It was observed that it is possible to generate a flat and high amplitude parametric resonance response, which implies a more sensitive sensor with a wider range of operation (bandwidth). Finally we present an ANSYS model of the system with the optimal parameters obtained in the numerical simulations.