Auxetic Grammars: An Application of Shape Grammar Using Shape Machine to Generate Auxetic Metamaterial Geometries for Fabricating Sustainable Kinetic Panels

Abstract

Auxetic materials are materials with a peculiar mechanical behavior compared to other regular materials. Its main difference exists in its reaction to tension. Most materials exhibit a positive Poisson’s ratio [1], that is, they laterally shrink when stretched or expand when compressed. On the contrary, auxetic materials exhibit a negative Poisson’s ratio (NPR), that is, they laterally expand when stretched or laterally shrink when compressed [2]. In this paper, the significance and role of geometry in auxetic materials’ behavior will be investigated. For this purpose, we will be using shape grammar rules with a strong generative tool called Shape Machine [3] to create auxetic geometries with their complex behavior out of simple rules. These geometries’ applications can be fabricating sustainable kinetic panels for buildings to interact with and adapt to the environment.