Performance of adaptive airfoil control system using shape memory alloy actuators for UAV

Shape memory alloy (SMA) is lightweight, produces high force and large deflection which makes it a suitable candidate for actuator in the adaptive airfoil system design. The deflection of a variable cambered wing is controlled by means of resistive heating of SMA actuator and cooling in the surrounding air. Experiments were conducted under wind tunnel conditions not only to verify the robustness of the adaptive airfoil control system but also to investigate the effects of its application on the aerodynamic behaviour of the wing. The change of forces acting on the wing with and without the adaptive airfoil control system was investigated. The results proved that the use of SMA actuators in the wing model is reliable as significant change in lift to drag ratio was detected when the wing was morphed. The adaptive airfoil control system was able to maintain the same L/Dmax for changing lift coefficient