Research on flexible honeycomb structure design for morphing aircraft

The wing skins of the morphing aircraft would be highly anisotropic with low in-plane extending stiffness to fit the wing transformation and high out-of-plane bending stiffness to undergo the aerodynamic loads. A material mechanics method is presented to evaluate the elastic modulus properties of the U-shape honeycomb structures. The U-shape honeycomb structures were proved to have low in-plane axial stiffness and good load resistance in other directions. Both finite element analysis and experimental tests were carried out to verify the accuracy of the proposed analytical formulation. And a theoretical analysis solution also was developed, which could well compare with both experimental results and FEA results. And the Possion´s ratio of the honeycomb structures was gained by FEA. It was also substantiated that U-shape honeycomb structures could be used for morphing aircraft wing skins.