Airbus’ Newest Design Is Based on Bones and Slime Mold
When you board a flight, you probably don’t notice the partition that separates the crew’s work station from the rest of the cabin. On an aircraft, people tend to pay attention to their seat, their neighbors, and whether there’s space for their carry-on bags. That partition is unglamorous infrastructure that fades into the background.
Unless, of course, you’re an aircraft manufacturer, in which case that partition is a major engineering headache. Like everything on an airplane, that wall must be as light as possible, and consume the smallest amount of space. And like everything on an airplane, it must be strong: That partition bears the weight of flight attendants who, during takeoff and landing, sit on fold-out chairs affixed to it. Such a requirement tends to make partitions heavy and bulky.
European aircraft manufacturer Airbus, like everyone else in the industry, wants to fly lighter, more efficient planes. In its mission to do, Airbus has joined Autodesk to rethink the design of those lowly partitions. Its new partition debuted today at the Autodesk University conference in Las Vegas and, thanks to 3-D printing and some wild new algorithms based on slime mold and bone growth, it weighs in at just 66 pounds. Airbus’s current partitions weigh 143 pounds apiece. “Our goal was to reduce the weight by 30 percent, and we altogether achieved weight reduction by 55 percent,” says Bastian Schaefer, innovation manager at Airbus. “And we’re right at the beginning.”
The beginning might more accurately be 2011, when Airbus unveiled Future By Airbus, its vision for flying in 2050. It included a concept cabin, many features of which were so forward-thinking as to seem frivolous or unattainable—like a virtual gaming wall for tennis, golf, and basketball. But other aspects of the plan, like aircraft components designed and printed with additive manufacturing techniques, were well within reach of current and near-future production practices. Schaefer says the more immediately attainable design objectives were particularly important to Airbus’s ambitions: “This is still the goal, to be able to print an entire airplane, or large components of it.”
More recently, Schaefer has worked with architect David Benjamin, principal of The Living, on making that “large component” part of the plan a reality. The Living is an avant-garde architecture practice that makes structures that are in some sense alive, like a tower of fungus bricks, or a glass building containing living frogs. Autodesk bought it last year as part of its effort to expand research on synthetic biology. With the Airbus partnership, Benjamin is still doing what The Living does—turning to biology for architectural inspiration—but this time it’s the software, not the materials, that are based on nature.
Benjamin has harnessed two naturally recurring design patterns and built algorithms that mimic them. His intention was to solve the load-bearing puzzle of the airplane partition with a design that weighed as little as possible. He describes the final product, the Bionic Partition, in terms of its macro design—the larger frame—and micro design, which includes the lattices connecting the bigger perimeter. Benjamin based the algorithm for the macro frame on the growth patterns of slime mold, a single-celled organism that can naturally, and uncannily, create a strong, efficient structure between two fixed points. The micro elements of the partition mimic mammalian bone growth, filling open spaces with delicate grid structures. Benjamin says the design principles are similar to those used by the Autodesk Within Medical program, which uses generative algorithms to create implants for reconstructive surgeries.
With these algorithms in place, Benjamin and Airbus could define parameters for the partition and let the software do its thing. “We can generate literally tens of thousands of design iterations, compared with the manual process which could generate maybe a dozen,” says Benjamin, echoing other advocates of generative design at Autodesk.
In the case of the crew partition, the resulting design is a web-like pattern that looks arbitrary but forms a net of optimized, load-bearing points. The final configuration requires minimal material—in this case, an alloy of aluminum, magnesium, and scandium called Scalmalloy—and is something a designer couldn’t conjure up on his own, says Benjamin. “A human might make something where, if you wanted to connect all the points, you would start at the perimeter, or start at the center and draw spokes,” he says. “It’s hard for a human with a rule-based brain to think of the complexity of connecting local neighborhoods, but also connecting the whole. The slime mold type of connectivity is a really fascinating way to connect two points.”
It would be easy for purists in the aeronautics industry to view this experimental approach with skepticism, but Richard Aboulafia, an aviation analyst at Teal Group Corporation, says such cross-pollination is essential. “There’s so much stuff going on outside the aircraft industry that it’s imperative that it migrates in,” he says. “How much bigger is the home construction business than the aircraft? There’s just more R&D.”
As for an entire aircraft that’s built like this partition, Aboulafia says it’s feasible, but that we’re years from seeing one. Designing a new airliner typically takes many years and many billions of dollars. “It depends on a new program launching which typically happens once a decade,” he says.
Since landing on the 66-pound partition, Airbus has subjected prototypes to a battery of tests. Like all aircraft components, the partition went through static and dynamic tests to simulate all the ways force is applied to airplane parts. “Everything about the project has been intended to make this real, according to current aerospace standards,” Benjamin says. Airbus could have the design installed in airplanes as early as next year.
Going forward, Schaefer says he hopes manufacturers apply generative design techniques to other, larger parts of the cabin. Just what might get The Living’s bio-design treatment remain confidential, but “you can imagine that when you build a wall here, you can apply this approach to any other wall in the airplane,” he says. “This is quite easy to do—David presses the button again, and we get a new kind of component.”