Static Deformation Analysis And Structural Topology Optimization Of 7R 6-DOF Spray Paint Robot

Spray robots are widely used for spraying operations due to their high quality spray,good work flexibility and high working efficiency.However,the static and dynamic stiffness of spray robots is an important index to measure the structural performance of robots.Therefore,it is of great significance to carry out research on stiffness performance and structure optimization design of the whole painting robot and to improve the static and dynamic characteristics of the robot structural parts,to improve the motion accuracy and overall performance of the robot.In this paper,the self-developed 7R6-DOF spraying robot is taken as the research object.Firstly,the three-dimensional finite element model of 7R6-DOF spraying robot are established,and the statics analysis is carried out.Secondly,according to the robot in different installation mode,the static deformation analysis of each position in the working space of the robot is carried out,and the static deformation distribution of the spraying robot in its working space is obtained.Finally,the deformation contribution rate of each component of the robot is analyzed at the position where the robot's deformation is large.Based on the analysis of the deformation of the robot along the gravity direction on the film thickness,the functional relationship between the distance and the thickness of the coating in the two function deposition model is deduced.According to the error range of car paint film thickness,the K value index for evaluating the range of robot deformation is deduced initially.In order to improve the static and dynamic characteristics of the spraying robot upper arm and realize the lightweight design of the robot,a new design method of topology optimization was put forward.Firstly,the dynamic analysis of the 7R6-DOF spraying robot based on the typical spray trajectory to obtain the joint load under multi-conditions.Secondly,the design region of initial arm model was released with maximum extent in the condition of assembly boundary conditions.By using the finite element software ABAQUS and optimization software TOSCA to realize the optimization design of the outline of robot arm.Then the quadratic topology optimization model was obtained based on the outline model.The topology optimization of the internal structure of the arm was realized under the outline constraint.Finally,a new arm structure was provided.The comparative analysis shows that the lightweight of the large arm structure is realized by using the new structure of the large arm,and the feasibility and effectiveness of the optimization method are verified.