A slicing and path generation method for 3D printing of periodic surface structure

Abstract

Periodic surface (PS) model holds enormous potential in the field of lightweight, heat management, and biomedical implants. To achieve tunable mechanical strength and high surface area versus volume (SA/V) ratio, it is imperative to achieve solid representation of the PS models. However, because of the complex inner structure, converting the surface model to solid model with uniform thickness remains a major challenge. In the meantime, the most pervasive practice to achieve tunable wall thickness is by offsetting the contour with a constant value or setting a constant value difference between two implicit functions. However, these existing approaches cannot guarantee uniform wall thickness. In this paper, a novel method is proposed to define an adjacent implicit surface with a uniform offset distance to the original. By repeatedly generating implicit surfaces with uniform distance from each other, the solid representation of the PS model with uniform thickness can be achieved. Meanwhile, a new slicing method allowing for the slicing without stereolithography (STL) file is developed to slice the implicit surfaces and generate the printing path so that the accumulation of slicing errors introduced by meshing steps can be avoided. By slicing each implicit surface separately, the corresponding G-code file is generated. This developed method is demonstrated by fabricating typical PS with fused filament 3D printing.