Abstract: Intelligent materials such as shape memory alloy, piezoelectric material and magnetostriction material have the functions of driving, bearing, transshaping and sensing. They can take the place of traditional actuators to significantly improve the compactness of the system. In order to meet the actual needs of morphing aircrafts, a variable winglet driven by the shape memory alloy (SMA) is designed and assessed. Based on the developed three-dimensional SMA constitutive model, and simulated the deformation process of the variable winglet driven by SMA rods and analyzed the influence of different SMA rod types on the deformation ability of the winglet. Combined with additive manufacturing technology, a prototype of the designed variable winglet is manufactured. single bending and repeated bending test were carried out. The results showed that the deformation data and the simulation results are in good agreement, and the designed variable winglet has good deformation ability and effect. Finally, the influence of the cooling rate of the SMA rods on the deformation ability of winglet was analyzed, the reason for the skin buckling during the deformation was evaluated and the follow-up research plan was proposed.

Key words: variable winglet, morphing structure, shape memory alloy, numerical simulation