Control of an XY Nano-Positioning Table for a Compact Nano-Machine Tool

Abstract

This paper describes the control of an XY nano-positioning table for a compact nano-machine tool. The aim of its controller design is to provide (1) high motion accuracy, (2) high robustness to disturbance forces and (3) high bandwidth. The controller has a PID element as a tandem compensator and a feedforward compensator. A bandpass filter is added so that the table system can show the mentioned specifications (1) and (2). The reference following characteristic and the robustness to disturbance forces are examined and evaluated theoretically and experimentally. The results prove that the table control system is suitable for a compact ultraprecision machine tool, attaining high positioning accuracy and frequency response up to 500Hz in a circular motion of a 100nm radius.