A New Method of Configuration Design about the 4-DOF and 5-DOF Parallel Robot on Base of the Screw Theory

The new method of constraint accession to the 4DOF and 5DOF parallel mechanism is provide with screw theory in this paper.The steps of structural synthesis are discussed that active kinematical chains control necessaries DOF,and driven kinematical chains control needless DOF.It is clarified by an example that new configurations can be got by assembling different kinematical limbs.