Airbus signs research agreement with MIT to explore use of digital manufacturing in aerospace vehicles
Airbus has signed a research agreement with the Massachusetts Institute of Technology (MIT) to explore the use of digital manufacturing in aerospace. Working with Neil Gershenfeld, director of MIT’s Center for Bits and Atoms (CBA) and his team, the aircraft manufacturer will evaluate how the digital material concepts being developed at MIT can potentially be applied to the design and construction of aerospace vehicles.
CBA was launched by a National Science Foundation award in 2001 to create a unique digital fabrication facility that gathers tools across disciplines and length scales for making and measuring things. These include electron microscopes and focused ion beam probes for nanostructures, laser micromachining and X-ray microtomography for microstructures, and multi-axis machining and 3D printing for macrostructures.
Digital material technology is based on the idea that a complex structure can be constructed by assembling a simple set of discrete components, similar to how the body builds all of its proteins from amino acids.
Carbon-fiber–reinforced composite materials can improve efficiency in engineered systems (for example, airframes) by reducing structural weight for given strength and stiffness requirements, but challenges with manufacturing and certification have slowed their adoption. High-performance composite components are conventionally constructed with many continuous fibers that span the shape of a component and are embedded in a resin matrix that is either pre-impregnated or subsequently infused. Parts produced in this way typically require custom tooling to form them, pressurization for consolidation, and heat for matrix curing. Each of these processes multiplies the time, cost, and inflexibility of design, production, and certification. Joint systems between different parts add further complexity and structural vulnerabilities.
The approach that we developed uses many small identical parts as regular building blocks. The parts integrate unidirectional fiber composite beams and looped fiber load-bearing holes that are reversibly linked, like chains, to form volume-filling lattice structures. These parts can be mass-produced and then assembled to fill arbitrary structural shapes, with a resolution prescribed by the part scale, which is chosen to match the variability of the boundary stress encountered in an application. Each type of identical part can be individually qualified, and as a cellular material, the periodic nature of their assemblies simplifies the analysis and prediction of their behavior.—Cheung and Gershenfeld (2013)
When the novel parts developed by MIT are assembled—much like snap-together building blocks—the resulting structure is not only lightweight, but also extremely durable and easy to disassemble and reassemble. The technique, which could lead to a completely new way of assembling airplanes, may offer substantial benefits, including lighter aircraft structures as well as lower construction and assembly costs.
|Models of digital composite airfoils from a CBA presentation. (Press the “i” key for index.) Click on the graphic to launch a video showing the airfoil flex. Source: CBA.|
As Airbus seeks to explore new efficient and cost-effective ways to design and manufacture its aircraft in the future, this approach radically challenges the traditional airframe architecture, which consists of manufacturing large structures or parts in single pieces.
Airbus is also exploring the use of 3D digital printing for the cost and weight saving potential it offers in the production of individual parts or even larger airframe structures.
Kenneth C. Cheung and Neil Gershenfeld (2013) “Reversibly Assembled Cellular Composite Materials,” Science 341, 1219 doi: 10.1126/science.1240889