Robust model-reaching control of high-precision linear motion systems

In this paper, a robust model-reaching control method is proposed for tracking of motion trajectory in high-precision linear positioning systems. The proposed method requires only the knowledge of the estimated parameters and their corresponding bounds as well as the bound of external disturbance in the implementation. The key idea of this method lies in the specification of a desired performance model and formulation of a robust scheme for a system to drive the position tracking error to converge to zero. Experiments are conducted on a two-axis stage for tracking a specified motion trajectory. The proposed method which is easily realized, produces superior tracking ability when compared to the popular PID plus feed-forward and model-based control schemes.