Continuous self-calibration canceling drive-induced errors in MEMS vibratory gyroscopes

We report a system for simultaneous rate readout and drift cancellation for MEMS vibratory gyroscopes without significantly affecting the sensor noise or bandwidth. The drift cancellation is accomplished by periodically reversing polarity of the gyroscope´s forcing voltage. As opposed to the state-of-the-art methods, our self-calibration does not interrupt normal gyroscope operation nor require a symmetric sensor. The proposed here self-calibration has enabled a five-fold reduction of the output drift (rate random walk) for ADXRS800 iMEMS gyroscope with a quadruple mass architecture.