When the Wright brothers accomplished their first powered flight more than a century ago, they controlled the motion of their Flyer 1 aircraft using wires and pulleys that bent and twisted the wood-and-canvas wings. This system was quite different than the separate, hinged flaps and ailerons that have performed those functions on most aircraft ever since. But now, thanks to some high-tech wizardry developed by engineers at MIT and NASA, some aircraft may be returning to their roots, with a new kind of bendable, “morphing” wing.
The new wing architecture, which could greatly simplify the manufacturing process and reduce fuel consumption by improving the wing’s aerodynamics, as well as improving its agility, is based on a system of tiny, lightweight subunits that could be assembled by a team of small specialized robots, and ultimately could be used to build the entire airframe. The wing would be covered by a “skin” made of overlapping pieces that might resemble scales or feathers.
The new concept is described in the journal Soft Robotics, in a paper by Neil Gershenfeld, director of MIT’s Center for Bits and Atoms (CBA); Benjamin Jenett, a CBA graduate student; Kenneth Cheung PhD ’12, a CBA alumnus and NASA research scientist; and four others.
Researchers have been trying for many years to achieve a reliable way of deforming wings as a substitute for the conventional, separate, moving surfaces, but all those efforts “have had little practical impact,” Gershenfeld says. The biggest problem was that most of these attempts relied on deforming the wing through the use of mechanical control structures within the wing, but these structures tended to be so heavy that they canceled out any efficiency advantages produced by the smoother aerodynamic surfaces. They also added complexity and reliability issues.
By contrast, Gershenfeld says, “We make the whole wing the mechanism. It’s not something we put into the wing.” In the team’s new approach, the whole shape of the wing can be changed, and twisted uniformly along its length, by activating two small motors that apply a twisting pressure to each wingtip.
This approach to the manufacture of aircraft, and potentially other technologies, is such a new idea that “I think we can say it is a philosophical revolution, opening the gate to disruptive innovation,” says Vincent Loubiere, a lead technologist for emerging technologies and concepts at Airbus, who was not directly involved in this research. He adds that “the perspectives and fields this approach opens are thrilling.”