A micro-motion wrist mechanism having the six degrees of freedom (CPM, Choi Platform Mechanism) is developed and manufactured for micro motion control. The CPM is composed of upper platform with one degree of orientation freedom and two degrees of translatory freedom to perform planar motion, lower platform with two degrees of orientation freedom and one degree of translatory freedom to perform spatial motion, so that has better assembling performance than Stewart Platform Mechanism(SPM) which has many constraints for motion of End-effector.
The basic kinematic equation of the manipulator is derived and simulation is carried out to show difference between SPM and CPM for both global and micro motion.
