Conceptual modeling of an adaptive torsion wing structure

This paper presents the conceptual analysis of a novel Active Aeroelastic Structure (AAS) device, which allows tailored twist deformations of wing structures to be achieved. The Adaptive Torsion Wing (ATW) concept is a thin-walled closed section two-spar wing-box whose torsional stiffness can be adjusted by changing the area enclosed between the front and rear spar webs. This is done by translating the spar webs in the chord-wise direction inward and towards each other using internal actuators. As the webs move closer to each other, the torsional stiffness of the structure reduces, while its bending stiffness in the span-wise direction is unaffected. The reduction in torsional stiffness allows external aerodynamic loads to induce twist on the structure and to maintain its deformed shape. These twist deformations can be controlled by changing the relative position of the webs as a function of the flight conditions to obtain an optimal or targeted level of performance. A Quasi-static Aeroelastic Suite has been developed in MATLAB™ to model the ATW concept and to study its behavior with respect to different web shifting strategies. Finally, the variation of structural figures of merit such as torsion constant, tip twist, shear centre position, and minimum actuation energy are evaluated and discussed.