Programmable Anisotropic Multi-stability in an Origami-inspired Metamaterial

In this project, we design, develop, fabricate and study a new class of 3D origami-inspired metamaterials with highly anisotropic mechanical instability and controlled reconfigurability. This metamaterial is constructed by connecting star-shaped units that are formed by folding an array of interconnected Miura-ori patterns, also known as origami string. The origami string is a one degree of freedom slender mechanisms in which we substituted paper and creases with 3D printed faces and revolute hinges, respectively. The star-shaped unit exhibits mechanically rich and strongly nonlinear behavior that includes bi-stability and reconfigurability. In addition, we introduce a 3D combination of star-shaped units with zero effective Poisson’s ratio in three orthogonal directions allowing its behavior in each loading direction to be programmed independently. The mechanical instability of this metamaterial in each orthogonal direction directly depends on the characteristics of star-shaped units aligned in that direction. Also, our study provides a framework to program the star units and create the desired properties in each orthogonal direction of the 3D metamaterial.