Three-degree-of-freedom plane parallel mechanism with novel redundant drive branched-chain

The invention discloses a three-degree-of-freedom plane parallel mechanism with novel redundant drive branched-chains, which belongs to the technical field of machinery manufacturing. The three-degree-of-freedom plane parallel mechanism comprises a quadrangular movable platform, three identical RRR branched-chains, an extendable branched-chain, an annular guide rail and a sliding block, wherein the movement of the three identical RRR branched-chains, the extendable branched-chain and the sliding block are driven and controlled through a servo motor; and the movable platform of the mechanism has three degrees of freedom, namely two translational degrees of freedom in a plane, and a rotational degree of freedom which is vertical to the plane. Due to the redundant drive branched-chains, the parallel mechanism is high in stiffness, and simultaneously, overcomes some singular configurations in an operational process, so that the working space of the mechanism is expanded. The redundant drive branched-chains of the mechanism can simultaneously control the size and orientation of tension and pressure applied to the movable platform, and can improve the accuracy of the movable platform in an operational process better through optimizing control.