(217dc) Adaptive Origami Structures and Their Mechanical Properties

In nature we find examples of a relatively small set of building blocks arranged in ways that give rise to properties that range orders of magnitudes. Specifically in bioelastomeric materials, only 20 different amino acids are used to synthesize proteins for the human body; yet they are arranged in such a way that proteins can have mechanical properties ranging from something resembling rubber – low stiffness, high resilience and extensibility – to silk – high stiffness and strength, and everything in between. The large variation in mechanical properties, such as strength and extensibility is enabled by secondary structures that undergo different degrees of conformational change. Using the same idea, we demonstrate the design and fabrication of tunable mechanical properties over orders of magnitude by both macroscopic and microscopic patterning of “secondary structures”. Here we report using three types of “paper”, including nanocomposite, to experimentally demonstrate using hierarchical structures to induce elastic instability. FEM results are compared to elucidate the effect of different geometries. The conformational change and instability involves deformation response out of the plane of the applied force, which can be potentially applied to flexible electronics and metamaterials over a range of length scales.