Researchers at Harvard University have developed a new type of material that can change size, shape, volume, and stiffness. It can be folded flat, withstand thousands of pounds of weight, and pop back up to be reshaped into another form. The researchers believe the 3D material could be used to design portable buildings and to transform walls in those buildings into windows.
The research team was led by Professor Katia Bertoldi, Senior Research Scientist James Weaver, and Chuck Hoberman from the Graduate School of Design. The material is described in the journal Nature Communications.
The design of the material is inspired by snapology, an origami technique. It is made from extruded cubes that have 24 faces and 36 edges. A cube can be folded along its edges in order to change its shape.
The researchers demonstrated theoretically and with a centimeter-scale prototype that by folding certain edges that act like hinges, the shape of the cube can be changed. They embedded pneumatic actuators in the structure that can deform hinges to change the shape and size of the cube without any need for external input.
The researchers connected 64 cells to make a 4x4x4 cube. It was able to grow, shrink, change shape and orientation, and fold completely flat. Changing the shape of the structure also changes its stiffness. The material can be made pliable or very stiff with the same design. These changes in the material’s properties add a fourth dimension to the structure’s material. The material can be embedded with other types of actuators, such as thermal, dielectric, or water.
The researchers at Harvard believe the new material could have many practical applications. They think it could be used for portable shelters, adaptive building facades, and retractable roofs. The material can work at a variety of scales, from nanoscale to meter-scale. It can be used to make small objects, such as surgical stents, and large pop-up domes to shelter victims of natural disasters.