University researchers have invented a distributed-mass micromachined gyroscope which minimizes quadrature error, eliminates effects of directional residual stresses, and completely decouples the drive and sense modes. The device has multiple drive-mode oscillators, distributed symmetrically around the center of a supporting frame. The multi-directional linear drive-mode and the rotational sense-mode allows complete decoupling of the drive and sense direction oscillations, minimizing instability and zero-rate drift due to dynamical coupling between the drive and sense modes. Due to the radial symmetry, the drive forces applied to the drive-mode oscillators cancel out in all directions, and the quadrature error is effectively nullified. The effects of directional residual stresses are also eliminated, due to the multi-directional and symmetric nature of the drive-mode oscillators. The device also provides a wide-bandwidth operation region in the drive-mode frequency response. By designing each drive-mode oscillator to have incrementally spaced resonance frequencies, the total Coriolis torque is set at a constant value over a wide range of driving frequency. If the sense-mode resonance frequency is designed to be accommodated in the same frequency band, robustness and insensitivity to parameter fluctuations is achieved.
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