Kalman Estimator-Based State-Feedback High-Precision Positioning Control for a Micro-scale Air-Bearing Stage

Due to the high positioning precision requirement and the low damping surface effect, the design of high-quality controller for a micro-scale air-bearing positioning stage is a challenging for micro-scale positioning system. Furthermore, the strict synchronization requirement of the linear motors on both sides of the gantry beam even intensifies the difficulty of the controller design. An optimized state-feedback gain has been designed by implementing a suitable Kalman estimator to minimize both the tracking error and the control efforts. Significantly, the merits of such a state-feedback control are the capabilities of handling the coupling of the two motors on the two outputs and compressing the overshooting as well. Finally, the experimental results of the proposed state-feedback controller on the air-bearing stage are displayed in comparison with the traditional PID control law.