Theoritical Study Of Two Novel Limited-dof Parallel Manipulators With Two Equivalent Composite Spherical Joints

Limited-DOF parallel manipulators boasts a broad and promising applicationprospect and gradually attract much attention within the field of parallel manipulator. Withrelatively more degree of freedom, the compound spherical joint Sccan effectivelysimplify the parallel manipulator and make them more compact, thus saving themanufacturing costs, due to which, it is widely used in the parallel manipulator. In thepaper, the author improves a kind of equivalent compound spherical joint Sewithsimplified structure of traditional Sc, which is more suitable for the actual situation.A closed forward displacement analysis is performed for a novel5-DoF parallelmanipulator (PM) with2Se. First, the kinematics model of a5-DoF4SPS+SPR PM with2Scare established. Second, the novel5-DoF PM with2Seis created based on4SPS+SPRPM by replacing each of2Scwith Se, and the formulae are derived for solving forwarddisplacement of the proposed5-DoF PM with2Se. Third, an analytic example is given forsolving forward displacement of proposed5-DoF PM with2Se, and the analytic solvedresults are verified by the simulation mechanism using CAD variation geometry.Two novel parallel manipulator (PM) with Seis proposed and its kinematics analyzedsystematically.The paper takes the advantage of the right triangle relationship obtained bybranch of Seand modifies the kinematics model unified in the parallel manipulator to let itapply the Separallel manipulator proposed by the paper. Two analytic example is given forsolving kinematics of proposed PM with Se, and the analytic solved results are verified bythe simulation mechanism.The writer sets up statics model with Sebased on the principle of virtual work.Besides, the writer figures out mapping relation between branch angular velocity of Seandmoving platform speed, as well as the supplementary linear branch angular velocity modelby using the binding relations of the organizations.then, the writer sets up the dynamicsunified model of Separallel manipulator on the basis of principle of virtual work. Inaddition, Two analytic example is given for solving dynamics of proposed PM with Se, andthe analytic solved results are verified by virtual prototyping technology.