Investigation of the effects of stiffness on control power via a morphing wing technology

The development of lightweight, flexible wings to improve the performance of an aircraft has been a desire of aircraft engineers since the dawn of the aerospace industry. For many years, wings have been designed stiff to counteract flutter and to meet the need for high speeds. Ailerons and flaps are primarily used for controlling the maneuverability of an aircraft. However, the mechanical actuation systems for these devices contribute significant weight to the wings and thus limit the performance of an aircraft. To reduce weight and increase the maneuverability of an aircraft, a wing morphing technique is proposed in this paper. This technique assumes that the wing structure is flexible enough to allow the wing to twist or bend to control the maneuverability of an aircraft without using ailerons or flaps. However, flexible wings require energy to deform and flutter is still a very important issue that needs to be addressed for flexible wings. Hence, the relationship between the degree of flexibility to meet stated performance requirements and both the desire for minimum control energy and the requirement for flutter avoidance is explored in this research. The research was conducted to determine how wing structural stiffness affects the energy required to deform the wing and to give insight into its performance range for which flutter is to be avoided. The study incorporates structural and aerodynamic modeling, control-design optimization, and a candidate wing morphing technology. The results provide important information that designers of morphing wings can consult to explore the potential benefits of morphing wing technology