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Creators/Authors contains: "El Helou, Charles"

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  1. Abstract Integrated circuits utilize networked logic gates to compute Boolean logic operations that are the foundation of modern computation and electronics. With the emergence of flexible electronic materials and devices, an opportunity exists to formulate digital logic from compliant, conductive materials. Here, we introduce a general method of leveraging cellular, mechanical metamaterials composed of conductive polymers to realize all digital logic gates and gate assemblies. We establish a method for applying conductive polymer networks to metamaterial constituents and correlate mechanical buckling modes with network connectivity. With this foundation, each of the conventional logic gates is realized in an equivalent mechanical metamaterial, leading to soft, conductive matter that thinks about applied mechanical stress. These findings may advance the growing fields of soft robotics and smart mechanical matter, and may be leveraged across length scales and physics. 
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  2. The development of materials with periodic microstructures provides the means to tune mechanical properties via prescribed collapse mechanisms. As investigations give attention to tunable unit cell designs, questions arise regarding strategic ways to exploit built‐up materials to empower large, programmable control over properties and material functionality. The potential to rationally design functionally graded elastomeric materials to yield prescribed mechanical properties is demonstrated herein. Following computational and experimental studies of simplified unit cells and layers, the results inspire ways to exploit linear elastic network analogies to design built‐up and functionally graded materials. This approach exemplifies a streamlined means to create pre‐programmed properties on the basis of simple calculations related to measurements from fundamental material constituents. The results build a foundation for innovative approaches to newly leverage elastomeric materials with programmable collapse for myriad engineering applications. 
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