A 3-D Material that Folds, Bends and Shrinks on its Own

Newest Inventions: A 3-D Material that Folds, Bends and Shrinks on its Own | Science ▶2 Harvard researchers design 3­D material with controllable shape and size. Harvard researchers have designed a new type of foldable material that is versatile, tunable and self actuated. It can change size, volume and shape; it can fold flat to withstand the weight of an elephant without breaking, and pop right back up to prepare for the next task. The structure is inspired by an origami technique called snapology, and is made from extruded cubes with 24 faces and 36 edges. Like origami, the cube can be folded along its edges to change shape. The team demonstrated, both theoretically and experimentally, that the cube can be deformed into many different shapes by folding certain edges, which act like hinges. The team embedded pneumatic actuators into the structure, which can be programmed to deform specific hinges, changing the cube’s shapes and size, and removing the need for external input. The team connected 64 of these individual cells to create a 4x4x4 cube that can grow, and shrink, change its shape globally, change the orientation of its microstructure and fold completely flat. As the structure changes shape, it also changes stiffness — meaning one could make a material that’s very pliable or very stiff using the same design. These actuated changes in material properties adds a fourth dimension to the material. The material can be embedded with any kind of actuator, including thermal, dielectric or even water. The research was supported by the Materials Research Science and Engineering Center, the National Science Foundation and the Wyss institute through the Seed Grant Program