Distributed Actuation and Control of a Tensegrity-Based Morphing Wing

Modern aircraft wings change shape via the deflection of discrete, hinged, control surfaces, which often exhibit areas of adverse pressure gradient along the hinge line, leading to flow separation and poor wing efficiency. To reduce surface discontinuities and sharp edges, a possible solution is to replace part of the conventional wing with a smart structure with distributed actuation, allowing subtle changes in curvature. Greater wing shape adaptability also allows better matching of the aerodynamic performance to the flight regime. This article presents an active tensegrity structure concept as the basis for a morphing wing. An experimental device has been designed and built, incorporating six pneumatic actuators giving four controlled shape-changing degrees-of-freedom, and two internal load paths controlled to maintain the pre-stress in the structure. The dynamic behavior of the smart structure has been investigated via a series of simulations and experiments. Wind tunnel test results have demonstrated that the prototype morphing wing is capable of achieving accurate shape control in the presence of a variety of aerodynamic load conditions and that its aerodynamic performance matches that predicted by simulation. As a lightweight controllable structure, it is a promising candidate for future development in the challenging field of morphing wing design.