Development of a nano-positioning planar motion stage

This paper develops a planar motion stage with high precision, long working range, and nano-positioning accuracy. The stage consists of a stage base, side walls, a carriage supported with eight air bearings, a magnetic suspension control unit, a magnetic actuation unit, and a two- dimensional optical encoder. Configuration design concepts are proposed for better operation characteristics. The structural characteristics of the stage are analyzed by static finite element method. The measurement system for this stage employs the two-dimensional optical encoder for sensing both X and Y positions. The multiple-input and multiple-output controller is used to control four sets of drivers independently.