In additive manufacturing, infill structures are commonly used to reduce the weight and cost of a solid part. Currently, most infill structure generation methods are based on the conventional 2.5-axis printing configuration, which, although able to satisfy the self-supporting condition on the infills, suffer from the well-known stair-case effect on the finished surface and the need of extensive support for overhang features. In this paper, based on the emerging continuous multi-axis printing configuration, we present a new lattice infill structure generation algorithm, which is able to achieve the self-supporting condition for both the infills and the boundary surface of the part. The algorithm critically relies on the use of three mutually orthogonal geodesic distance fields that are embedded in the tetrahedral mesh of the solid model. The intersection between the iso-geodesic distance surfaces of these three geodesic distance fields naturally forms the desired lattice of infill structure, while the density of the infills can be conveniently controlled by adjusting the iso-values. The lattice infill pattern in each curved slicing layer is trimmed to conform to an Eulerian graph so to generate a continuous printing path, which can effectively reduce the retractions of the nozzle during the printing process. In addition, to cater to the collision-free requirement and to improve the printing efficiency, we also propose a printing sequence optimization algorithm for determining a collision-free order of printing of the connected lattice infills, which seeks to reduce the air-move length of the nozzle. Ample experiments in both computer simulation and physical printing are performed, and the results give a preliminary confirmation of the advantages of our methodology.

在增材制造中，填充结构通常用于减少实体零件的重量和成本。当前，大多数填充结构生成方法是基于常规的2.5轴打印配置的，尽管能够满足填充上的自支撑条件，但仍存在着众所周知的对完成表面的阶梯效应和需求的困扰。对悬垂功能的广泛支持。在本文中，基于新兴的连续多轴打印配置，我们提出了一种新的晶格填充结构生成算法，该算法能够实现零件的填充物和边界表面的自支撑条件。该算法至关重要地依赖于使用嵌入在实体模型的四面体网格中的三个相互正交的测地距离场。这三个测地距离场的等大地距离面之间的交点自然形成了填充结构的所需晶格，而填充物的密度可以通过调整等值值方便地进行控制。修剪每个弯曲切片层中的晶格填充图案以使其符合欧拉图，从而生成连续的打印路径，这可以有效减少打印过程中喷嘴的缩回。另外，为了满足无碰撞的要求并提高印刷效率，我们还提出了一种印刷顺序优化算法，用于确定所连接的格子填充物的无碰撞印刷顺序，力图减小空气移动的长度。喷嘴的 在计算机仿真和物理打印方面都进行了大量实验，