Design Of Morphing Skin Based On Origami Structure

As a multi form aircraft,morphing aircraft can effectively improve the flight performance by changing the external form during the flight,so that it can ma intain the optimal performance in real time and adapt to the multitask requirements.The morphing aircraft uses different wing configurations to perform different flight tasks.This makes the skin of the wing surface changed,which is a new test for the co ntinuity,smoothness and carrying capacity of the skin,and the quality of the skin has a great influence on the overall flight performance of the wing.In view of the shortage of the material with large rigidity in the traditional skin and the small extension of the material under the load,this paper takes the morphing wing tip aircraft as the research object,and proposes a wing skin based on Miura origami structure.The skin is made up of the basic unit of the Miura paper structure,uses the structure features of the Miura origami the larger deformation amount required in the wing folding process is converted into a superposition of a number of local strains and rigid rotational displacement.In combination with the rotational degree of freedom of the Miura folding unit,the skin is made of shape memory polymer material with variable stiffness characteristics.With the shape memory polymer will change stiffness under certain conditions,the folding skin is driven in the wing folding,the shape memory polymer is converted to rubber state,and the modulus is reduced significantly.With the increase of ductility,the overall stiffness of the folded paper skin structure is reduced,and the deformation capacity is enhanced,so that the rigid body rotation in the Miura origami unit can be realized.In this paper,firstly,calculated the effect of the geometric parameters on the deformation of the structure of whether the Miura structure is considered in thickness,then,used the Python script in ABAQUS software bulit a folded skin structure with folded airfoil curves,and discussed the influence of geometric parameters on the mechanical properties of the element.Finally,compared the effect of mechanical properties with the aerodynamic performance and static bearing capacity of the folding structure between the skin and the flat skin,which shows that the folded skin has larger deformation in plane and out of plane stiffness,which is suitable for flying at low Maher numbers.Variable stiffness origami skin structure is an integrated structure with deformation and load bearing.Under the load,the folding area will produce a large amount of deformation,which is a new way to produce a large deformation for wing surface.