On The Design, Simulation And Experiment Of Open Thin Wall Flexure Joints For Parallel Robots

Parallel robot is a kind of new branch of robot since the series robot wasdeveloped. Lots of advantages like high rigidity, well carrying capacity, high speedwith high kinematic precision and well dynamic performance are presented in parallelrobot. The parallel robots are easier to get vibrating or strike by the gaps between jointparts which are also earlier to be worn-out. Even though mainly studies are focused onflexure joint design, statics and dynamics analysis with experiments, the studies forflexure joint parallel robots are still not enough. So the theoretical and experimentalstudy of both flexure joint mechanism and the parallel robot with flexure joint arevery important and valuable.A flexure joint is designed and manufactured in this paper. Firstly, the kinematicsanalysis is worked out based on the structure of3-RRR parallel robot. The inversesolution of joint rotation movement is done. Based on the joint rotation range andrequired rigidity as design requirement, the geometry parameters of joint aredetermined. The advantages of large range of motions and fixed rotation axis arepresented in this joint. The joint is made of65Mn spring steel.Beside the theroretical, the joint modeling is also created in Solidworks andimported into ANSYS for stress analysis during the linkage moving process. In thestatics experiment, the strain of both open thin wall flexure joint and leaf springflexure joint are measured based on the simulation of linkage movement. Thecomparison between simulation and experiments is made and the strength of open thinflexure joint is testified.Finally, the experiments with both leaf spring and open thin-walled flexure jointsare presented. The flexure joints parallel robots experiments plat is built with changedsection linkages. The trajectory experiments can be carried out on the parallel robotwith open thin-walled flexure joints and its superiorities are presented by comparewith the3-RRR parallel robot and leaf spring experiments results.