Research On Optimization Design Of The Rotary Worktable For Vertical Lathe Based On Structural Bionic Method

In order to improve the ability of independent innovation in equipmentmanufacturing industry and strengthen the application of new design method and theoryin the structure design of large NC machine tools, the rotary worktable of vertical lathe isoptimization designed based on the structural bionic, topological optimization and sizeoptimization design method. And the objective of optimization design is to improve thestructure’s stiffness and to reduce its weight. This paper combines structural bionic withtopological optimization, providing a new idea for optimization design on getting morereasonable structure.The paper’s primary coverage is as follows:First, the importance of large NC machine tools in equipment manufacturingindustry is illustrated. And the present development situation of the finite elementmethod, structural bionic method, topological optimization method and size optimizationdesign method in optimization design of machine tools structure are systematicallysummarized. Then the main research contents of this paper are illustrated.Secondly, according to the design requirements of vertical lathe, the rotaryworktable components are conventionally designed. Through the design, the supportingscheme and control system scheme are determined. At the same time, the detailedmechanical structure of the rotary worktable component is designed. By finite elementmethod, the rotary worktable which is conventionally designed is analyzed using ANSYSWorkbench. And this is the foundation of research on optimization design for the rotaryworktable.Thirdly, based on the structural bionic method, the optimized objectives needs of therotary worktable are analyzed, and we are looking for bionic prototype. Through fuzzysimilarity analysis, the similarity of the Victoria amazonica and the rotary worktable isobtained. And Victoria amazonica is selected for rotary worktable’s bionic prototype.Then according to the bionic prototype, two bionic optimization models are established.Finally the rationality of the bionic models is verified by statics analysis, and the betterone is selected to be used on the rotary worktable.Fourthly, based on the idea of establishing the bionic model of the rotary worktable,using the topological optimization variable density method, the rotary worktable isdesigned aiming at compliance minimization and volume minimization, respectively. The supporting skeleton structure of the rotary worktable is extracted, and the topologicalmodel of the rotary worktable is established. The topological model, the bionic modeland the conventional model are compared to each other, and the optimization effect isverified.Finally, with the APDL language command stream file, the parameterized rotaryworktable model is established without changing the structure of the topological modelof the rotary worktable. Based on the zero-order optimization method, key dimensions ofthe topological model of the worktable are optimized, and the best group of dimensionsis obtained. Then, the fabrication properties, installation and usage are considered, andthe final comprehensive optimized model is obtained. The finite element analysis provesthat the comprehensive optimized model has higher stiffness and lower weight comparedto the conventional model.The structure optimization design makes the rotary worktable’s structure anddimensions more reasonable. It realizes the optimization target that enhancing thestructure’s stiffness and reducing the structure’s mass, and it provides a feasible methodfor the optimization design of rotary worktable. At the same time, the idea that usingstructural bionic and topological optimization to determine structure, and that using sizeoptimization to define dimensions has certain reference significance for other machinestructure optimization design.