Design of a 3-DOF parallel translating manipulator with U-P-U joints kinematic chains

An analytical and algebraic procedure based on the screw-systems theory for the design of general parallel manipulators is presented. After recalling some theoretical features, serial kinematic chains are considered and then arranged in parallel, the resulting motion being specified as an elementary screw-system. Finally, constraints for the geometrical design as well as kinematic properties are deduced. The method described is applied to the design of a parallel structure with U-P-U joint kinematic chains.