Cloverleaf microgyroscope with electrostatic alignment and tuning

摘要

A micro-gyroscope (10) having closed loop output operation by a control voltage (V_ty), that is demodulated by a drive axis (x-axis) signal V_thx of the sense electrodes (S1, S2), providing Coriolis torque rebalance to prevent displacement of the micro-gyroscope (10) on the output axis (y-axis) V_thy˜0. Closed loop drive axis torque, V_tx maintains a constant drive axis amplitude signal, V_thx. The present invention provides independent alignment and tuning of the micro-gyroscope by using separate electrodes and electrostatic bias voltages to adjust alignment and tuning. A quadrature amplitude signal, or cross-axis transfer function peak amplitude is used to detect misalignment that is corrected to zero by an electrostatic bias voltage adjustment. The cross-axis transfer function is either V_thy/V_ty or V_tnx/V_tx. A quadrature signal noise level, or difference in natural frequencies estimated from measurements of the transfer functions is used to detect residual mistuning, that is corrected to zero by a second electrostatic bias voltage adjustment.