Multi-modal mechanical stimuli stage for in-situ calibration of MEMS gyroscopes

We report a multi-axis piezoelectric multi-modal mechanical stimuli stage capable of in-situ calibration of MEMS gyroscopes attached to the stage. The system is fully self-contained with electronics for portable operation. In this work, we demonstrate active calibration of a commercial Z-axis gyroscope ADXRS646 for high bandwidth applications. The dithered stage is capable of pure sinusoidal angular rates at 0-300 deg/s even after being loaded with a gyroscope die, to extract the scale factor and the bias. The stage has the added capability of X-Y in-plane acceleration stimulus 0-90 m/s² to extract the cross-axis sensitivities which are essential parameters. The measured maximum in-plane cross-axis sensitivity for unpackaged gyro ~ 13.64% (S^x/S^y x 100) operated at ~800Hz bandwidth, providing high bandwidth calibration data useful for personal navigation. The maximum power consumption of the unloaded calibration stage is ~396mWatts during calibration.