Project morphAIR: DLR tests deformable wings

Flexible surfaces instead of flaps: The German Aerospace Center (DLR) is testing wings that deform in flight. These are intended to make aircraft more efficient and safer.

Morphing Technologies & Artificial Intelligence Research Group (morphAIR) is the name of the project in which wings were developed that change during flight. “The morphing wing can change its shape during flight and thus adapt optimally to different flight conditions,” says project leader Martin Radestock from the DLR Institute for Composite Structures and Adaptive Systems.

The DLR team has developed two sets of wings, both made of fiber composite materials. These wing sets were then tested on the unmanned DLR research aircraft Proteus.

The morphing wings have a shape-variable trailing edge, called hyperelastic trailing edge morphing (HyTEM), which deforms without gaps or steps. Small motors accomplish this. “The HyTEM concept replaces conventional flaps and ailerons with an intelligent system of multiple actuators distributed across the wingspan,” says Radestock. “These can precisely adjust the profiles at ten points without creating gaps between the areas.”

Advantage for aerodynamics and flight mechanics

The continuous shape reduces the wing's profile drag. In addition, lift, induced drag, and aircraft control can be specifically influenced, explains Radestock. This represents “a great advantage for aerodynamics and flight mechanics.” However, the system is not only intended to improve efficiency but also to ensure greater safety, as control functions can be distributed across the entire wing.

The complex HyTEM system is controlled by an artificial intelligence (AI) flight control system developed and trained by the DLR Institute of Flight Systems Engineering. Training also included simulating damage or failure of individual control surfaces. This allowed the algorithm to learn to recognize changes in flight and control the still intact actuators in such a way that the flight behavior remains as stable as possible.

DLR mounted the morphing wings on the unmanned research aircraft Proteus and tested them at the National Experimental Center for Unmanned Aerial Systems in Cochstedt, Saxony-Anhalt. The initial tests were successful, according to DLR: both the morphing wings and the reference wings proved to be airworthy.

DLR plans another test campaign with Proteus later this year. The aim will be to investigate, among other things, whether the system can also be scaled for larger aircraft. The system will then be further developed in the UAdapt (Unmanned Aircraft Wing Adaption) project.

(wpl)