Researchers at the Massachusetts Institute of Technology (MIT) have created a novel material whose lightweight components can be fit together like LEGO pieces, according to a paper which appears in a recent issue of the journal Science. According to the researchers, the new material may revolutionize the construction of aircraft, spacecraft, and large-scale construction projects such as bridges and levees.
The paper, entitled “Reversibly Assembled Cellular Composite Materials,” co-authored by postdoctoral researcher Kenneth Cheun and director of MIT’s Center for Bits and Atoms Neil Gershenfeld, describes the development effort of the material as a combination of the research fields of fiber composites, cellular materials, and additive manufacturing.
The resultant structure, which Gershenfeld likens to chainmail, is 10 tens stiffer than current ultra-light materials. In addition, the structure can be assembled and disassembled with ease, which makes the task of repairing damage or recycling parts into different configurations much less cumbersome than that which would normally be experienced with conventional building materials. Cheung and Gershenfeld are currently developing a robotic system to assemble the individual pieces, which can be mass-produced, into aircraft components, rockets, bridges, and many other structures.
The added benefit of this process is that each component will be fabricated as a continuous unit, which eliminates the need for multiple facilities to make individual parts that must be joined farther on into the construction process. This challenge has been witnessed with the construction of Boeing’s 787 Dreamliner.
The impetus for the development of the process arose in response to the query, “Can you 3-D print an airplane?” As Gershenfeld and Cheung realized how difficult 3-D printing would be at the large scales required in the construction of aircraft and bridges, the duo sought to examine the possibility of using the “digital” materials that they were already studying as possible candidates for a similar process. According to Gershenfeld, “This satisfies the spirit of the question, but it’s assembled rather than printed.”
As the composite material spreads out stresses across the entire structure, Gershenfeld and Cheung believe that the system would fail incrementally, which makes damage to the structure easier to repair. The new approach to building composite structures has attracted the attention of Airbus innovation program director Alain Fontaine, who commented that this novel approach, “is really disruptive. It opens interesting opportunities in the way to design and manufacture aerostructures.”
Gershenfeld and Cheung’s work received support from the Defense Advanced Research Projects Agency (DARPA), the sponsors of the Center for Bits and Atoms, and Spirit Aerosystems – which collaborated on the composite development.