Performance Analysis And Design Of 2-PSS&2-P2(?) Parallel Robot Mechanism

The progress of robot technology has promoted the development of modern mechanisms.Mechanism is the skeleton and actuator of the robot,which is used to complete the functional requirements of the robot system.The topology is an important part of modern mechanisms and it provides an effective method for mechanism innovation.However,there is no systematic theory to support whether the kinematic characteristics of the same topology structure has scale effect.This thesis chooses 2-PSS&2-P2(?) parallel robot mechanism to study the scale parameter's impact on the kinematic characteristics of the same topology structure first.Then,for a novel 4-DOF parallel robot mechanism,this thesis designs the kinematic parameters and analyzes the spatial static stiffness.Finally,some applications of the novel mechanism are given.For 2-PSS&2-P2(?) parallel robot mechanism,thirty kinds of structures were constructed by changing the scale parameter conditions first.Using the traditional formula for the degree of freedom and kinematic simulations to give the primary research for kinematic characteristics,it is found that there are differences in their kinematic characteristics.The direct and inverse kinematic models of the 2-PSS&2-P2(?) parallel robot mechanism are established,and the forward position solutions are obtained based on Jacobian matrix methed which further supplement and verify the software simulation results.On the basis of this analysis,the velocity,acceleration and singularity of the EM11(C_s~pC_p~pC_s~pC_p~p,named EM11)are analyzed.It finds a general numerical approach to the pose description of this kind of parallel robot mechanism.It also gives the specific analytic methods to the pose description of EM11 and EM12(C_s~pC_?~pC_s~pC_?~p,named EM12)according to their structure characteristics.Taking EM12 as the research object,it shows the necessity of using the minimum output dimension to describe the output of the mechanism motion.The workspace of the EM11 is got based on the inverse kinematics,and the kinematic structure parameters are designed preliminary according to the requirements of the workspace and force transfer performance.A method is presented to evaluate the performance of 3T1R parallel robot mechanism based on the Jacobian matrix determinant.According to the analysis of the singularity of the EM11,the corresponding avoidance strategies are put forward.Finally,the kinematic parameters of the mechanism are determined,and the validity of the design method is verified.Based on the superposition principle under small deformation and the virtual mechanism method,the spatial static stiffness matrix of the EM11 is obtained.Then the results got by the numerical method and the results received by the finite element analysis software are compared.The results of the comparison show that the method is effective.