Tuning The Primary Resonance of Vibrating Beam Micro-Gyroscopes Based On Piezoelectric Actuation and Multiple Nonlinearities

In this paper, the nonlinear dynamic characteristics of statically piezoelectric actuated vibrating beam micro-gyroscopes are studied. The comprehensive nonlinear model including curvature, inertia and electrostatic force nonlinearities is considered. In the research of electrostatic micro-gyroscopes, it’s a novel way to tune the primary resonance by piezoelectric actuation and multiple nonlinearities. The multiple scales method and numerical continuation technique are used to characterize the frequency-amplitude and force-amplitude responses of the micro-gyroscopes. The effect of varying the size-dependent, fringing field, statically piezoelectric voltage and nonlinear curvature and inertia on the dynamic response of the micro-gyroscope is investigated in detail. The frequency-response results show that small vibrations produce a symmetrical frequency response curve in sense direction while the system actually has a significant softening characteristic in drive direction. The nonlinear multi-value problem effectively reduces in sense direction under the size-dependent effect, which plays an important role in the design of detection instruments for micro-gyroscopes. Choosing a positive piezoelectric actuation voltage will obtain a higher sensitivity. Increasing the curvature nonlinearity and reducing the inertial nonlinearity of the gyroscopic system will help the micro-gyroscope obtain better sensitivity, and may eliminate multi-valued responses as much as possible.

Design and Simulation of a Z-Axis Dual Proof Mass Micromachined Gyroscope with Decoupled Oscillation Modes

In this paper, a Z-axis micromachined gyroscope with a new decoupled design was presented. The gyroscope consists of dual proof mass, sense frame and drive frame structure. The sense frame is constrained in the sense direction and anchored on the substrate, which minimize the influence from the motion of the proof mass in the drive direction. The drive frame is also restricted to oscillate in the drive direction. ANSYS has been used to make modal analysis and harmonic analysis to determine the vibration characteristics of the decoupled gyroscope. We introduce the decoupling ratio (ηDtS) of drive mode to sense mode and the decoupling ratio (ηStD) of sense mode to drive mode to determine the decoupling design. The results show that the drive mode and the sense mode are well decoupled.