Design of a four-degree-of-freedom nano positioner utilizing electromagnetic actuators and flexure mechanisms

Positioning devices are widely used in industrial applications. High precision is a key performance of the positioner and recently high precision positioners for advanced applications are required to satisfy other performances such as larger motion range, nanometer level precision, and multiple degree-of-freedom (DOF) motion within compact size. We propose a new 4-DOF high-precision positioner employing voice coil motors and flexure guides. Millimeter motion range and nano level resolution were achieved simultaneously, utilizing the frictionless characteristic of the voice coil motors and the flexures. The mathematical model describing static and dynamic behaviors of the positioner was developed and the design parameters were optimized to achieve the best performances. The proposed positioner was manufactured with the size of 180 × 180 × 30.7 mm(3) which was very compact. The experiment of feedback control showed the motion range more than 1.80 × 1.80 mm(2) in-plane and 0.3 mm vertically and the minimum resolution of 10 nm in-plane and 14 nm vertically.