Extended high-gain observer for robust position control of a micro-gripper in air and vacuum

This paper aims to develop a position tracking controller for a micro-gripper´s tip. The controller should be robust, able to compensate external disturbances and perform precise reference tracking under parameter variation and incertitudes. It becomes clear when considering the gripper´s response on two different environments: air and vacuum. In this work, two models were identified based on experimental data, one for each case of study, and an extended high-gain observer controller based on output feedback is proposed. Simulations show that the controller, chosen to achieve a desired performance for the system in air, is able to maintain similar results in vacuum. The proposed setup was implemented in real-time for the system in air and simulated for vacuum.