Design, Analysis and Experimental Testing of a Morphing Wing

The aim of this work is to illustrate a new wing morphing concept and to compare its performance with the conventional wing-flap configuration. While there is no formal definition for the word "morphing", it is usually considered to mean large shape change or transfiguration. In the field of aeronautics, "shape morphing" has been used to identify those aircraft that undergo significant geometrical changes to enhance or adapt to their mission profiles. This investigation aims to find out more about non conventional solutions over the classical wing structural design. The main goal in this research is to replace the ordinary wing structure adopted on a model aircraft with a new morphing wing. In this way, aerodynamic performances during different flight conditions may be improved thanks to the prevention of typical aerodynamic losses caused by geometrical discontinuities in conventional designs. The ability of a wing surface to change its geometry during flight has interested researchers and designers over the years as this reduces the design compromises required. Conventional flap systems inevitably contain discontinuous sections that cause aerodynamic losses, and this is the point where using a morphing technology that would prevent those aerodynamic losses makes sense. Wing morphing concepts can be classified into three major shape changing types: planform alternation, out-of-plane transformation, and airfoil adjustment. An example of planform alteration is wing span resizing through telescopic structures. The morphing wing in the telescopic designs is sectioned longitudinally to form several segments with reducing cross sectional area, such that each segment can be accommodated in the adjacent inner segment with a minimum sliding clearance. Given the required length change, the number of segments can be determined. Neal et al. designed and demonstrated a variable planform aircraft capable of such wing span resizing. Airfoil profile adjustment has been the less explored way of morphing. Austin et al. examined variable length trusses to reshape the airfoil. They attached linear displacement actuators inside the wing section in a diagonal manner. The airfoil shape could therefore be modified by the expansion or contraction of the actuators. Although the idea of changing the wing camber was born with the first airplanes, it is far from simple to design devices capable of achieving the necessary deformation and suitable control systems. Airfoil adjustment is mainly concerned with camber variation, although there is also some research concerned with thickness change. In this research, a new morphing mechanism using rapidly prototyped structural elements and a bio-inspired geometry is proposed to perform an out of plane transformation through profile chord wise bending. A rotating mechanism created by means of a rod connected to a linear actuator positioned at the root of the wing, led each rib to de ect at least up to 40 degrees. This deflection carried downwards the wing trailing edge to enable the shape change.