Research On The Performance Analysis And Control Experiment Of Sperical 2-DOF Redundantly Actuated Parallel Robot

The spherical 2-DOF redundantly actuated parallel manipulator is obtained on the basis of spherical 5R parallel manipulator which adds a same driving branch.It has the advantages of higher bearing capacity,higher rigidity and the continuous workspace with few singularity,it can be applied to locating device on the spherical surface,and has good application prospects.Therefore,this article takes the spherical 2-DOF redundantly actuated parallel robot as research object,and researches the kinematics,the performance and the control experiment.The positive and inverse position solution kinematics model of spherical 2-DOF redundantly actuated parallel manipulator is established based on the geometric constraint equation.The workspace is solved based on the actual constraints of the prototype.The two spherical path within the workspace are planned,and the kinematics track is planned by the trajectory planning method that acceleration is combined sine function.On the basis of the principle of virtual work,the discontinuous stiffness mapping model is established by considering the influence of the joint stiffness?the bar's selfrespect and the load,and the output displacement error caused by the elastic deformation is analyzed.The finite element model of static stiffness is established based on ANSYS,and the static stiffness and the elastic deformation are analyzed when the mechanism is under the different attitude with different load.The rigid-flexible joint simulation model is established based on ANSYS and ADAMS,and the elastic deformation are analyzed when the mechanism is in the process of movement.In order to study the trajectory tracking vibration phenomenon in the process of movement of a spherical 2-DOF redundantly actuated parallel robot,this article researches the elastodynamics.The elastodynamic model is built based on the finite element method,the natural frequencies and the output dynamic responses within the workspace are analyzed.The mechanism simulation model and motor control simulation model are built based on SimMechanics and Simlink,the simulation with the hybrid control of force/position is completed through the input torques optimization.And this method is verified which can improve the actuator's output accuracy and stability by the prototype's control experiment.