Static Design of a Selective Compliance Morphing Wing Profile Based on Integrated Variable Stiffness Bi-Stable Components

The realisation of morphing requires an efficient internal structure capable of significant shape adaptations, implying vastly anisotropic stiffness properties. In this context, introducing variable stiffness elements into distributed compliance systems shows great promise. Specifically, bi-stable laminates demonstrate stiffness variability characteristics arising from the markedly different properties of each equilibrium configuration. This paper presents a novel concept of a morphing wing section based on a distributed arrangement of embeddable variable stiffness bi-stable composites. The final configuration emerges from parameter studies into positioning distinct optimised bi-stable elements within a NACA 0012 profile. The structural response of the aerofoil is assessed numerically, with a particular focus on the global stiffness modification potential as well as exploring the snap-through behaviour of the component laminates. Final specimen manufacturing and testing validates the numerical strategy developed, confirming the feasibility of the innovative morphing approach based on variable stiffness bi-stable elements integrated into a selectively compliant system.