Active disturbance rejection control for MEMS gyroscopes

A new control method is presented to drive the drive axis of a MEMS gyroscope to resonance and regulate the output amplitude of the axis to a fixed level. It is based on a unique active disturbance rejection control (ADRC) strategy, which actively estimates and compensates for internal dynamic changes of the plant and external disturbances in real time. The stability analysis shows that both the estimation error and the tracking error of the drive axis output are bounded and the upper bounds of the errors monotonously decrease with the bandwidths. The control system is simulated and tested using a field programmable gate array (FPGA)-based digital implementation on a piezoelectric vibration gyroscope. Both simulation and experimental results demonstrate that the proposed control method not only drives the drive axis to vibrate along the desired trajectory but also compensates for manufacture imperfections in a robust fashion that is insensitive to parameter variations and noises.