Parametric Modeling of Lattice Structures for Manufacturing via Masked Stereolithography Apparatus

Abstract

Abstract An investigation into parametric modeling of lattice structures is conducted in pursuit of an effective and efficient process for manufacturing lattice structures via masked stereolithography apparatus (MSLA). Principals of Design for Additive Manufacturing (DfAM) are applied, keeping in mind the manufacturing process to be used. Key design features are parameterized to decrease the effort required to design and implement changes to the structures. Unit cells are modeled as interconnected struts according to parameters such as unit cell side length and strut diameter or thickness. As well as parameterizing the unit cell geometry, the number of cells in each of the three cartesian directions are parameterized such that a three dimensional array of unit cells is constructed based on the single unit cell. Three unit cells are to be considered: the simple cubic (SC) unit cell, the body-centered cubic + simple cubic (BCC|SC) unit cell, and the face-centered cubic + simple cubic (FCC|SC) unit cell. A simple procedure for interfacing the lattice to bulk material is proposed. The proposed design process is validated through qualitative analysis of lattice samples designed with varying unit cell and overall lattice properties with results supporting future studies. Additionally, an example of replacing a solid model’s interior with the lattice structure is detailed to demonstrate the simplicity and power of the approach. It is found that even very thin features with maximum dimensions less than 10 pixels or layers depending on feature orientation (0.34mm and 0.5mm, respectively) are able to be manufactured using affordable consumer grade equipment, which allows for a multitude of potential applications from general purpose lightening to primitive object strength augmentation.