Application of Active Disturbance Rejection Control to Micro-Electro-Mechanism System Transducers

Abstract

Active disturbance rejection control(ADRC) is an emerging robust control technology. It improves the performance of micro-electro-mechanism system(MEMS) sensors and actuators and increases their measurement and displacement accuracies through effectively compensating the imperfections in micro-fabrications and environmental variations. The applications of an ADRC to MEMS gyroscopes and electrostatic actuators are introduced in this paper. The ADRC facilitates accurate sensing of both constant and time-varying rotation rates for MEMS gyroscopes. In addition, an alternative ADRC is initially applied to an electro-static actuator. The alternative ADRC is constructed based on partially known model information. It drives and stabilizes the displacement output of an electrostatic actuator to 99% of full capacitor gap despite of the presence of disturbance. The alternative ADRC also has better noise rejection capability than traditional ADRC. Simulation and experimental results demonstrate the robustness, effectiveness and feasibility of the ADRC in MEMS area.