On Precision Motion Control for an Industrial Long-Stroke Motion System with a Nonlinear Micropositioning Actuator

In this study, we propose a control technique that can be used to significantly reduce the tracking error of a short-stroke motion system whose dynamics are considered totally unknown with possibly input and output nonlinearities. As an example, the tracking performance of a uni-axial piezoceramic actuated positioning stage is examined under mainly sinusoidal test input signals with various frequencies and amplitudes, where we show that the proposed controller does invert the plant dynamics. Interestingly, neither modeling nor identification of the stage dynamics is needed. Mainly, the indented operation bandwidth is the only needed information when the proposed controller is synthesized. Experimental results demonstrate the effectiveness of the proposed approach when the piezoceramic actuated stage is attached to an existing long-stroke positioning motion system as an add-on to motivate the former usefulness in specifically enhancing the performance of wafer scanner machines used in semiconductor manufacturing.