Planar positioning system and method of using the same

A planar positioning system having a flat base comprising

• a X-axis assembly having a X-axis linear actuator means arranged orthogonal to the Y-axis;
• a Y-axis assembly having a pair of Y-axis linear actuator means mounted onto the flat base forming a H-configuration;
• a Z-axis assembly having an aerostatic bearing mechanism that floats on thin film of externally pressurized air on top of the flat base, wherein a movement in the Z-axis is segregated into a coarse Z-position and a fine Z-position, and wherein the coarse Z-position adjustment is actuated by means of a pneumatic system with the topmost critical movement being frozen by a kinematically determinate construction of three precision shafts sitting on three vee grooves;
• a θ-axis assembly having actuator anchored from the X-axis to drive the Z-axis assembly which carries a workpiece, wherein the Z-axis assembly is rotated with the rotary axis for the θ-axis perpendicular to the flat base;
• and
• three fine positioning actuators placed 120 degrees apart, wherein the fine Z-position adjustment is carried out by a mechanism formed by the said three fine positioning actuators, said mechanism being the three degrees of freedom to attain the statically determinate final unique Z-position.