Model Based Sliding Mode Control for a 3-DOF Translational Micro Parallel Positioning Stage

This paper presents mechanical system dynamics modeling analysis and control of a novel compliant flexure-based micro-parallel positioning stage. The designed microparallel positioning stage consists of a mobile plate, a fixed base, and three limbs with identical kinematic structure. Certain geometric conditions are adopted to make the mobile plate with purely 3 translational degrees of freedoms. Each limb connects the mobile base to the fixed plate through a (P) over bar (prismatic) joint and two U (universal) joints in sequence, where (P) over bar joint is the active joint driven by a pair of novel electromagnetic actuators assembled on the fixed base. The prototype of the designed system is fabricated, dynamics model of the manipulator is constructed through Lagrange method and sliding mode controller is designed based on the dynamics model.