Research On Structure Optimization In 3D Printing

The traditional product development process is divided into two stages of product design and manufacturing, which are responsible by the design and manufacturing en-gineers respectively. It gradually formed an independent mode that can be described as "we designed, you create". In this development mode, there is little communication between design and manufacture engineers, which cause high cost, long cycle, and low quality problems. To solve these problems, design for manufacturing pattern emerged. Design for manufacturing refers to the design engineers should consider the manufac-turing requirements at the design stage of the product, so that the design product has good manufacturability to avoid the cost, manufacturing and quality problems.3D printing has a huge potential and enduring vitality in the field of design for manufacturing. It is considered as an import sign of the third industrial revolution. The creation of a 3D printed object is achieved using additive processes in which an object is created by laying down successive layers of material until the entire object is cre-ated. Each of these layers can be seen as a thinly sliced horizontal cross-section of the eventual object. Therefore even though it’s called "printing", it is really a "manufactur-ing" process based on 3D model. It effectively links up the gap between the virtual 3D model design and the real products which make the two stages more tightly connected together. Therefore, it is important to full play the advantages of 3D printing technology to achieve design for manufacturing which can promote manufacturing industry mode transformation and upgrading.In this context, based on summarizing the related existing research results, this paper presents some works on structure optimization problem in 3D printing. In chap-ter two, we introduce the related research achievements which were classified from material savings, strength, stability and support optimization aspects. Some of the ad-vantages and disadvantages of existing research results are analyzed. From material savings perspective, the third chapter consider how to optimize model to reduce print material consumption and printing costs without sacrificing print quality of the object surface. To solve this problem, we present a topology optimization algorithm for min-imal volume in 3D printing with traditional evolutionary structural optimization meth-ods combined with Von Mises stress. The algorithm calculates Von Mises stress of the model to guide the evolution of the volume reducing, until the maximum Von Mises stress reaches the allowable stress value of the material. Furthermore, we introduces multi-resolution technology to accelerate optimization computing with from the coarse tetrahedral meshes to fine meshes, which effectively improve the computational effi-ciency. Compared to other existing methods, the optimization results of our method can be more flexible and better reflect the load transfer path of model under the given force.Many models designed by individual users may have some structural or stress de-fects as the users may be lack of manufacturing experience. Concerning this issue, we present an approach to help users analyze a model’s structural strength while designing its shape in chapter four. We adopt sectional structural analysis instead of conventional FEM analysis which is computationally expensive. Based on sectional structural anal-ysis, our approach imports skeletons to assist in integrating mesh designing, strength computing and mesh correction well. Skeletons can also guide sections building and load calculation for analysis. For weak regions with high stress over a threshold value in the model after analysis, our system corrects them by scaling the corresponding bones of skeleton so as to make these regions stiff enough. A number of experiments have demonstrated the applicability and practicability of our approach. In chapter five, we summarize our paper and present some future work from the view of geometric com-puting and structure optimization in 3D printing.