Modulation of Auxeticity of Kirigami-Inspired Programmable Metamaterials

This study investigates the auxetic behavior of a truncated octahedron-based mechanical metamaterial structure, characterized by a negative Poisson’s ratio (NPR). A detailed CAD model was developed to represent the unit cell geometry, featuring surface bodies with extrusions and connectors for tessellation into one-dimensional and two-dimensional structures. Finite element simulations using Ansys were performed to analyze the structural response under compressive loads, incorporating static structural and rigid body dynamic analyses. The material properties of structural steel, along with varying geometric parameters such as side length, extrusion length, and connector length, were utilized to study deformation behavior and validate NPR characteristics. To further validate the auxetic nature, analytical formulations were derived to study deformation angles and Poisson’s ratio. MATLAB was employed to implement deterministic analysis. This comprehensive approach, combining CAD modeling, finite element analysis, and statistical validation, demonstrated the reliability of the auxetic response of truncated octahedron-based structures. The findings enhance our understanding of NPR metamaterials, paving the way for potential applications in energy absorption, impact resistance, and flexible mechanical systems.