GyFoam: Fabricating Lattice Foam with Customizable Stiffness through Uniform Expansion

We present GyFoam, a fabrication method integrating foam material with lattice structure to enable controlled and uniform expansion, which supports high-quality forming in appearance and customizable stiffness in function, using standard 3D printers, filaments, commercially available Thermo-Expandable Microspheres and silicone. To achieve customizable stiffness, we propose two methods: modifying material concentration and adjusting lattice structural parameters. Additionally, we propose three shape control strategies for creating complex shapes: bending, wavy edges, and internal doming. Furthermore, a user-friendly design tool is established for users to construct lattice structures, preview basic deformation, and generate mold models for printing. Finally, through a series of applications, we validate GyFoam’s practical usage of fabricating large objects, wearable products, enabling flexible interactions and creating aesthetic designs.