Research On Structural Optimization And Lightweighting Of Mechanical Arm Of Industrial Robot

Industrial robots play an irreplaceable role in the manufacturing industry.With the high attention of the country to the manufacturing industry and the rapid development of modern science and technology,in the future,the market for industrial robots will continue to expand.The increase of market demand will put forward the requirements of high speed and high precision for industrial robots.Therefore,in terms of structure,industrial robots are required to be light in weight,high in strength and good in stiffness,and to achieve the purpose of quick response,large in load and small in deformation in actual work.The research object is the big arm structure of ER20-C10 6-DOF Industrial robot.Firstly,the topology of the big arm is optimized based on the original model.Before optimization,first of all,the big arm should be analyzed to determine whether the big arm model is reasonable or not,and also provide the basis for the verification of optimization results after optimization.The static analysis of the big arm is carried out by Inspire software,and the modal analysis of the big arm is carried out by ANSYS Workbench software.When the topology of the big arm is optimized,Inspire software is used,and the static analysis is carried out directly in the software after completion.The model after topology optimization can not be analyzed and verified again because of a large number of meshes in the process of optimization.In order to solve this problem,the optimized big arm clean in ANSA software,and then the mesh is divided.The model after meshing is imported into ANSYS Workbench for modal analysis.Comparing the analysis results before and after the optimization,and it is found that the optimized big arm can improve the stiffness and the minimum safety factor,reduce the maximum stress and reduce the mass.The orthogonal test design can achieve the equivalent results with a large number of comprehensive tests through the statistical analysis of representative test points.On the premise of ensuring the existing functions of the big arm,the orthogonal test design is used to reduce the number of topology optimization in the research of the optimal structure of the big arm.According to the analysis results of each orthogonal test,the range of each influencing factor is continuously reduced,and the optimal big arm structure is finally confirmed.The modal analysis and statics analysis are carried out for the optimized big arm structure.The method and steps used in the analysis are the same as those in the previous section.Compared with the original model,the minimum safety factor of the optimized big arm is significantly improved,the maximum displacement and stress are significantly reduced,and the mass is also reduced.Compared with the structure optimized on the basis of the original model,in addition to the improvement of quality,all parameters have been improved.The lightweight of the big arm is studied from two aspects: material replacement and lattice structure.After replacing the big arm material with aluminum alloy,the strength of the big arm structure decreases and the maximum displacement increases under the same constraints and loads.Therefore,the orthogonal test method is used again to find the optimal structural performance,and finally the optimal lightweight scheme of the big arm is obtained.The lightweight big arm has achieved remarkable results on the basis of ensuring better strength and stiffness.Lattice structure has the mechanical characteristics of light weight,high specific strength,low density and other high-quality mechanical properties.Making full use of the lattice gap structure,it can also realize the integration of functions,greatly expand the design direction.Lattice structure is applied to the lightweight of the big arm.The structural performance under different parameters is discussed,and the lattice optimization scheme of the big arm structure is confirmed.It can be seen from the static analysis that the maximum stress is further reduced compared with other schemes.This paper provides an important idea for the research and design of the mechanical structure of industrial robots,and a feasible reference scheme for the structural optimization and lightweight of similar products.