Morphing Wing Based on Composite Elastic Periodic Structure and Pre-Morphing Mechanism

A flexible large-deformation morphing wing based on variable-height composite elastic periodic structures and silicone rubber flexible skins was designed using the NACA0014 airfoil. A pre-morphing mechanism was introduced to address the stiffness issue of flexible silicone rubber skins. Under the premise of satisfying structural strength and stiffness, nonmechanical chord extension and camber variation were achieved. Finite element models and aerodynamic analysis models of the morphing wing were established to evaluate its morphing capability, aerodynamic performance, static strength, and dynamic response. The results show that the pre-morphing design effectively improves the normal stiffness of the silicone rubber flexible skin. The wing can achieve chordwise morphing up to 23.3% and [Formula: see text] deflection angle, and lift and lift-drag ratio increase by 181.24% and 24.10% compared to the original wing. The strength, stiffness and stability requirements of the wing are met under severe and economic cruise load cases. Initial damage of the elastic periodic structure occurs under the critical load which is 2.44 times the static strength load, and the damage mode is fiber compression failure. The wing displacement converges to cruise level within 1.5 s under gust load. The morphing wing with variable-height composite elastic periodic structures incorporating pre-morphing mechanism improves the stiffness of flexible skins, simplifies the morphing method, and significantly enhances the aerodynamic performance of the wing.