Design And Comprehensive Performance Analysis Of Parallel Mechanism Based On Anti-hinge Four-bar Structure

With the continuous development of industrial technology,industrial production has put forward higher and higher requirements on robot design.In this paper,the 3-R(RPU & RPU)parallel robot based on the anti-articulated four-bar mechanism is deeply researched in the manufacturing industry for the needs of industrial robots.The main research includes structural theory,inverse kinematics,positive position solution,singularity of workspace,static performance prediction and comparison.The main research results are as follows:(1)Structural theory.The rigid characteristics of the four-bar linkage with the hinged four-bar linkage in plane motion are analyzed.The possibility of constructing a parallel robot with the four-bar linkage is deduced.A three-dimensional solid model of 3-R(RPU & RPU)parallel robot is constructed.Draw a diagram of the mechanism and analyze the mechanism of the mechanism accordingly.Using spiral theory to analyze the degree of freedom of the mechanism,the number of degrees of freedom and the movement form of the mechanism are determined.(2)Kinematics.Based on the structural analysis,the pose-attitude equation of 3-R(RPU & RPU)parallel robot was established by using closed-loop vector method.The position inverse solution model and inverse velocity model of mechanism were obtained based on vector equation.basis.At the same time,based on the pose equation,a positive model of the parallel mechanism is established.(3)Workspace and strange shape.Based on the traditional definition of working space,five working spaces are defined to help analyze the performance of the organization.The influence constraints on the length of the working space,the kinematic secondary angle and the interference of the connecting rod are solved.Then the method of numerical search is used to obtain the reachable working space of the institution and the position and attitude of the institution is limited to obtain the position space of the institution.Based on the location space,the influence of the size parameter on the work space was studied.The complete Jacobian matrix is used to analyze the singularity of parallel robots.(4)Institutional static performance estimation and comparison.The finite element model of the structure is established by using SolidWorks Simulation powerful finite element analysis module,and then the static stiffness analysis of the parallel robot is established.On this basis,the differences in the static stiffness of three different types of parallel robots are analyzed and compared.It proves the static stiffness advantage of the trans-3-R(RPU & RPU)parallel robot in the periphery of the working space,so as to expand the working space of the parallel robot.The anti-hinge four-bar mechanism in the parallel robot laid the foundation for the application.