Research Status of Materials and Structural Design of 3D Printed Parts Considering the Factor of Gravity Balance

If 3D printing is a functional unit, making sure that it can remain stable is a main challenge from the model transforming into practical parts. This paper focuses on the codesign strategy for materials and structures to achieve gravitational balance during 3D printing processes. In terms of materials, choosing multi-material 3D printing and functional gradient material printing to realize density gradient printing. By distributing materials of different densities, a component with front heaviness similar to a toppling doll is achieved. This method takes advantage of the fact that the materials change the center of gravity position and moment of inertia of the component, and adds topological optimization in the low-density material area, which greatly reduces the influence of gravity on the printed component. In the structural section, the key structural design strategies that have emerged to solve this problem are systematically reviewed.First of all, discussing the static optimization method based on a single material, including the technology of controlling the center of mass through internal hollowing and fine-tuning the shape, as well as the scheme of achieving the coordinated optimization of lightweight and mechanical properties through density gradient filling. And then, introducing the dynamic balance design, which means the movable mass block method. It achieves adaptive stability under various complex working conditions.