||CMC: Computers, Materials & Continua, Vol. 32, No. 1, pp. 61-80, 2012
||Full length paper in PDF format. Size = 1,055,807 bytes
||Morphing skin, Honeycomb, Elastomer, Simulation, Optimization
||The morphing skin has been a main obstacle in the real-world implementation of morphing aircrafts. This paper presents a morphing skin made of the elastomer reinforced by the honeycomb structure. A matrix made from elastomer provides possibilities to configure the morphing skin and the honeycomb structure with smaller in-plane modulus and larger out-of-plane modulus is thought to be suitable to reinforce the elastomer. The polyurethane elastomer is selected and synthesized by the casting method with the prepolymer approach, after which a tensile test is conducted to get its stress-strain relationship. To decrease the skin depth and diminish the local deformation in the honeycomb cell, the elastomer is filled into the honeycomb core rather than just working as the flexible face sheets, which leads to the so-called honeycomb reinforced elastomer. To present its mechanical properties finite element method is applied to analyze the morphing skin with a plug-in of commercial software Abaqus developed to model the skin in details. Different geometry and material parameters are taken into consideration with three kinds of results calculated namely, the equivalent tensile modulus, the non-dimensionalized equivalent three-point bending stiffness and the linear strain capacity. After the simulation analysis, samples of the morphing skins are fabricated by the compression molds method and the tensile tests have verified both the concept and the simulation results. At last, an optimization performed has shown a significant decline of the tensile modulus and out-of-plane displacement of the morphing skin.