Configuration Design And Kinematics Analysis Of A (2-RRR&RPR+R)&URS Parallel Mechanism

Nowadays,the parallel mechanism has been widely used in the mechanical automation production industry,especially in some specific occasions,such as the transportation of goods,the packaging of food,the pick-up and sorting of express delivery,etc.In this paper,a parallel picking and sorting mechanism which can quickly pick up and put the goods on one conveyor belt to another conveyor belt is studied based on the application background of picking and putting the goods in the express industry.Based on this kind of movement form,design a(2-RRR&RPR + R)& URS parallel mechanism,in the organization configuration,the location is,inverse kinematics,static stiffness and modal analysis is studied and the instance simulation and research show that the parallel mechanism compared with tandem pick up institutions have larger rigidity and response speed,work space,can meet the current logistics industry to the demand of the quick pick up sorting items.The main contents of the study are summarized as follows:1.Configuration design of parallel picking mechanism.A 4-DOF parallel mechanism was designed according to the functional requirements of industrial pickup mechanism.The degree of freedom of the parallel mechanism was analyzed based on the screw theory,that is,a four-degree of freedom movement with two movements and two rotions could be realized.The correctness of the screw theory analysis was verified by the improved G-K formula,and the selection of driving pairs of the mechanism was analyzed and determined.2.The position of the(2-RRR&RPR+R)&URS parallel mechanism was analyzed.Based on the static and dynamic coordinate systems established,the inverse position solution model of the parallel mechanism was established by the closed-loop vector method through the coordinate transformation relationship of Euler Angle,and the calculation equation of the inverse position solution was obtained,and the corresponding inverse solution example was calculated.Based on the particle swarm optimization algorithm,the forward solution of the parallel mechanism was solved.Through the comparison of the forward and inverse solution examples,as well as the theoretical calculation and simulation verification by using MATLAB and ADAMS software,the correctness of the mechanism position model was illustrated.3.The 4-DOF parallel pickup mechanism was analyzed kinematically.On the basis of the above theory,the expression of the velocity and acceleration of the mechanism was obtained through the derivation method,and the mapping relationship between the input and output was obtained.The variation diagram of the parameters of the set motion calculated by MATLAB programming was compared with the simulation results of the virtual prototype to verify that the kinematic performance of the mechanism was good.The numerical search method was used to solve the reachable workspace of the parallel mechanism.The results show that the workspace has no void and good continuity,which can meet the design requirements of picking operation.4.The parallel picking mechanism of(2-RRR&RPR+R)&URS was analyzed by finite element method.Institutions based on Solidworks and ANSYS Workbench on the finite element static rigidity and modal analysis,through the establishment of institutions Solidworks 3 d model is imported into the analysis in the ANSYS Workbench,by institutions under the posture of five kinds of typical deformation nephogram and first six order natural frequency and the corresponding vibration mode cloud,through analysis shows that the institution exists in the configuration design of weak links,and provide the basis for subsequent structure optimization design.5.The(2-RRR&RPR+R)&URS parallel pickup mechanism was simulated by a motion example.Here will be Solidworks established three-dimensional model into ADAMS software to carry on the simulation,set a certain trajectory and add the corresponding driver to simulate the pick up of agency action,through the curve of the simulation results show that the parallel pick up agency to complete the desired motion,can realize continuous in X,Z plane point movement,meet to pick up the range of movement,further verify the feasibility of the design.