Redundantly actuated mechanism synthesis of the symmetrical unconstrained branched chain parallel mechanism

A mechanism synthesis method on redundantly actuated branched chain of symmetrical unconstrained branched chain parallel mechanism was put forward in this paper, and the redundantly actuated branched chain and its number of the lower-mobility parallel mechanism with 4 degrees of freedom (DOF) were synthesized. First the brached chain with less rods of one line vector, one couple and mixture of line vectors and couples were selected, based on synthesis method on redundantly actuated branched chain of uncontrained branched chain parallel mechanism, the redundantly actuated parallel mechanism with practical meanings of 4 DOF was synthesized; Under different branched chain constrained screw systems, the corresponding number of redundanly actuated branched chains was given out. And a 4-SPS/RzPzUxy parallel mechanism was synthesized out. The research result showed that the method was simple and effective.