Digital design and fabrication of two-dimensional soft lattice structures with genotype patterns

Abstract

Emerging additive manufacturing technologies allow the fabrication of complex designs with favorable properties such as mechanically efficient lattices for engineering and biomedical applications. For example, soft lattice structures such as silicones are broadly used in soft robotics and flexible electronics due to their high flexibility and mechanical behavior. This paper aims to develop an additive manufacturing strategy that allows the fabrication of two-dimensional elastic soft structures with cost-effective stereolithography. The proposed architecture for the lattice structures is based on a new family pattern called genotypes. Six types of lattice structures based on genotypes (A, C, L, O, P and K) and two regular structures (square and hexagonal) were designed, simulated, manufactured, and tested using a compression test. The mechanical behavior of the 2D lattice structures was analyzed by studying the compressive strength-stretching curve. The 2D lattices tested show two types of mechanical rubber-like behavior: linear (L and K) and quadratic (A, C, P, and hexagonal). The O and hexagonal genotypes have more complex behavior that an adequate mathematical model cannot be found. The design and application of new geometric shapes and architectures to porous materials in conjunction with advanced additive manufacturing techniques allow a rapid evolution towards the engineering of increasingly complex products and devices that can be connected to other technologies.