Design And Experimental Research On Smart Skins Made Of Composite Materials

Smart skin is one of the most important technologies to realize the morphing aircraft.In order to meet the aerodynamic requirements of morphing aircraft and withstand aerodynamic loads,smart skin should be sufficiently flexible in the longitudinal direction and show resistance against bending loads.On the basis of the existing research on cellular smart skin and the advanced technologies in the field of composites,a design of smart skin made of composite materials is proposed in this thesis.What’s more,the mechanical properties of this skin are analyzed and its manufacturing process is also explored.Finally,a driving device is designed with shape memory alloy(SMA)wire and the deformation capability of the composite smart skin is testified experimentally.The main research contents and results of this thesis are as follows:1.The mechanical properties of different unit cellular structures are analyzed,which means the expressions of the in-plane mechanical properties of them are derived together with numerical verification,in order to determine a most suitable cell structure.In addition,the in-plane moduli of cellular structures made of composites are also studied and then verified numerically.2.The components of the designed composite smart skin are introduced in detail and the manufacture process of this skin is explored.The constitutive relation of a silicone rubber face sheet is acquired by experimentally testifying its material constants and its in-plane extension behavior is simulated under different boundary conditions.On this basis,both the tensile and shear morphing deformation of the composite smart skin are conducted through the numerical simulation.And the results could verify both the transverse and sweepback deformation capabilities of the smart skin.3.The mechanical performance of SMA is testified experimentally following the analysis of the characteristics of SMA,the driving mechanism of this actuating material and its simulation method.According to the above fundamental study,a SMA antagonistic actuator is designed further and an experimental platform for testifying the deformation properties of the smart skin is built.The results indicate the feasibility of the proposed composite smart skin actuated by the designed SMA actuator and the deformability of the composite smart skin.