Development of an UAV with a variable-span morphing wing

Abstract

Morphing concepts for Unmanned Aerial Vehicles (UAVs) have been a significant topic in recent aerospace research field. The morphing wing is a bird-like wing and one concept of morphing is to change the wing configuration to accommodate multiple flight regimes. A variable-span morphing wing (VSMW) is designed to change its wing span for various flight conditions to reduce drag or increase maneuverability. The wing area and the aspect ratio of the VSMW increase as the wingspan increases. Total lift increases while the induced drag is reduced, whereas the wing root bending moment increases. Thus it requires a larger bending stiffness of the wing structure. The purpose of the present study is to investigate the aerodynamic characteristics and structural stability of a VSMW. Aerodynamic, structural, and aeroelastic analyses of a VSMW are performed by using AVL and MSC/NASTRAN, respectively. A semi-monocoque concept without front and rear spars is proposed to build a VSMW. Based on this concept a VSMW wing and its actuating mechanism are designed, fabricated, and tested. The developed VSMW is applied to an UAV and its flight test is performed to verify its performance and structural stability.