Implementation and Self-Tuning Adaptive Control Design of an Electromagnetic Submicro-positioner

A novel, compact and two degree-of-freedom (DOF) submicro-positioner with a large travel range is presented. The design of the submicro-positioner utilizes a monolithic parallel flexure mechanism with built-in electromagnetic actuators and eddy current sensors to achieve the 2-DOF motion. We have analyzed the dynamics of the positioner and derived its analytical model. The whole control architecture takes two configuration parameters measured by the two sensors and endeavors to control the 2-DOF motion through regulating the current in the electromagnetic actuators. To let the compact system be more robust and stable in positioning, we propose a self-tuning adaptive controller (STA) to improve the system regulation and tracking performances. From the experimental results, satisfactory performances of the system, including stiffness and precision, have been successfully demonstrated