Structural optimization design of working table of direct-drive machine tool based on a dragonfly wing structure

Abstract

To improve the stiffness and to realize the lightweight of the working table of the direct-drive machine tool, the similarity between the working table and wing structure is analyzed. The structural characteristics of the wing membrane and veins are used as the design guidelines for the bionic design of the ribbed plate structure of the working table. A new bionic wing working table is finally obtained. The static properties of the common table, the bionic leaf table, and the bionic wing table are compared with finite element simulation. A 3D printer is used to fabricate an equally scaled-down model of the working table, and the reliability of the simulation results is verified through static load experiments. Deformation morphology and stiffness-strengthening mechanisms of three types of working tables are studied through methods combining compression experiments and FEM analysis. The research results show that the bionic wing table has the most decrease in static deformation among the three tables with similar masses. Compared to the common table, the maximum deformation of the bionic wing table is reduced by 25.6% and the average deformation is reduced by 21.9%. The compressive strength of the bionic wing table is significantly higher than that of the common and bionic leaf tables. The integrated design of the transverse partition with an imitation wing membrane design and the stiffener with an imitation wing vein design can improve the torsional stiffness of the stiffener. The deformation of the stiffener is mainly compression, and compressive S-type curves with two half-waves symmetrically centered on the transverse partition are created. The layout of the bionic rib plate based on the structural features of the wing can effectively improve the strength and stiffness of the working table of the direct-drive machine tool. The working table has a uniform distribution of deformation to guarantee high machining accuracy of the machine tool.