Design And Application Of 3D Printing Lightweight Structure Based On Voronoi Diagram

Lightweight is an important research direction in manufacturing,and is also the goal that designers constantly pursue.At present,there are two main ways to achieve lightweight:one is to use lightweight materials,and the other is to use lightweight structure.This paper mainly focuses on the latter.However,lightweight structure can be divided into two categories:one is to obtain a better size and topology structure through the constraints and forces of parts,the result cannot be known before optimization,such as topology optimization.The second is to replace the parts that need to be optimized with lightweight structures,whose results can be predicted,such as various sandwich structures.Sandwich structures,especially three-dimensional lattice structures,are generally complex and have two difficulties:one is the complexity of generating methods,and the other is that it is hard to be manufactured by traditional manufacturing methods.As a new manufacturing technology,3D printing can perfectly solve the second difficulty,manufacturing difficulty,and this paper will seek a solution for the first difficulty.In this paper,a lightweight sandwich structure generation method based on Voronoi diagram is proposed.The research objects include irregular honeycomb structure generated by two-dimensional Voronoi diagram and irregular foam structure generated by three-dimensional Voronoi diagram.The main research contents and results are as follows:(1)An algorithm for generating irregular Voronoi diagram and corresponding solid model is proposed,and its parameters such as irregularity,relative density and mesh density are defined.(2)The finite element simulation method was used to study the influence of the above parameters on the elastic properties of the structure.The results show that the larger the irregularity is,the elastic modulus increases and then decreases.The higher the relative density,the more meshed,the higher the elastic modulus.(3)On the basis of studying the influence of different printing parameters on the mechanical properties of 3D printing parts by orthogonal experiments method,two kinds of lightweight structural entities were produced by selecting appropriate parameters.The simulation results were verified by tension and compression experiments,and the experimental results were basically consistent with the simulation results.(4)Applied the two structures to the front and rear girders of the wing of a certain type of small unmanned aerial vehicle.The mechanical simulation was carried out respectively,and the performance before and after optimization was compared to verify the usability of the structure.The results show that the maximum stress of the wing increases after optimization,but within the allowable range,the maximum displacement increases slightly,the low-order natural frequency increases,and under the premise of model simplification,the mass is reduced by 19.67%and 16.24%respectively,which proves that the structures have certain application value.