Procedural Metamaterials: A Unified Procedural Graph for Metamaterial Design

Abstract

We introduce a compact, intuitive procedural graph representation for cellular metamaterials, which are small-scale, tileable structures that can be architected to exhibit many useful material properties. Because the structures' "architectures" vary widely -- with elements such as beams, thin shells, and solid bulks -- it is difficult to explore them using existing representations. Generic approaches like voxel grids are versatile, but it is cumbersome to represent and edit individual structures; architecture-specific approaches address these issues, but are incompatible with one another. By contrast, our procedural graph succinctly represents the construction process for any structure using a simple skeleton annotated with spatially-varying thickness. To express the highly-constrained triply periodic minimal surfaces (TPMS) in this manner, we present the first fully-automated version of the conjugate surface construction method, which allows novices to create complex TPMS from intuitive input. We demonstrate our representation's expressiveness, accuracy, and compactness by constructing a wide range of established structures and hundreds of novel structures with diverse architectures and material properties. We also conduct a user study to verify our representation's ease-of-use and ability to expand engineers' capacity for exploration.