A Unified Procedural Graph for Metamaterial Design

We introduce a compact, intuitive procedural graph representation for the full spectrum of mechanical metamaterials. The "architecture" of each metamaterial may contain elements such as trusses, curved beams, thin shells, or solid bulks. However, it is challenging to explore these diverse architectures using existing representations. Generic approaches like voxel grids are versatile, but representing and editing any individual structure is cumbersome. Architecture-specific representations address these issues, but are generally incompatible with one another. We propose a unified procedural graph that succinctly represents the construction process for any structure using a simple skeleton annotated with spatially-varying thickness. By extending this design philosophy to all architectures, we greatly expand engineers' capacity for exploration. To demonstrate the expressiveness, accuracy and efficiency of our representation, we recreate a wide range of established structures. We also show that random searches over our representation can efficiently produce large collections of novel structures with promising material properties.