harvard builds cross-functional metamaterial that could reinvent prototyping for designers

researchers at the harvard SEAS have found a way to design reconfigurable metamaterials—that’s smart materials with more that one function, which can interchange between their different properties. metamaterials are materials whose function is determined by structure, not composition. existing metamaterials have been designed to transform from soft to stiff, bend light and sounds, and even damped seismic waves from earthquakes. however, each of these functions requires a unique mechanical structure, making such metamaterials great for a specific task, but difficult to use broadly.

researchers at harvard set out to solve this problem, and have in turn created a framework to design reconfigurable metamaterials, which would be able to contain multiple functions within a single structure, and easily switch between them. the design strategy that the researchers have produced is scale independent, meaning that it can be used for everything from huge building materials to nano-scale systems such as photonic crystals and waveguides.

the design process started with a simple extruded cube that could easily fold and change shape. the team built on this idea to create structures of larger metamaterials using laser-cut cardboard and double sided tape. like origami, the resulting structures could be folded along its edges to change shape. by combining design and computational modeling, the team were able to identify a wide range of different rearrangements and create a blueprint for building those materials in the future. 

katia bertoldi, john l. loeb associate professor of the natural sciences at SEAS elaborates on their creation, explaining that ‘in terms of reconfigurable metamaterials, the design space is incredibly large and so the challenge is to come up with smart strategies to explore it. through a collaboration with designers and mathematicians, we found a way to generalize these rules and quickly generate a lot of interesting designs.’

now that the design process has been formalized, the team can move on to think about new ways to fabricate and reconfigure these metamaterials on a smaller scale. the idea would involve using 3D printing techniques to create environmentally responsive prototypes. the materials could then be useful for structural and aerospace engineers, material scientists, physicists, robotic engineers, biomedical engineers, designers and architects.