Preliminary Inquiry Into Configuration And Performance Of Large Deformation Flexible Skin For Morphing Wing

One of development directions of future aircrafts is morphing wing.Flexible in deformation direction and stiff in the direction perpendicular to the deformation direction are essential to get smooth large deformation and withstanding large aerodynamic loads. Corrugated-form is very flexible in the corrugation (longitudinal) direction and show enough resistance against bending loads in the direction (transverse) perpendicular to the corrugation. So, corrugated-form is expected to be a candidate to develop skin of morphing wings. In this investigation, research focus was put on the corrugated-form composites. On the other hand, honeycomb core flexible skin was preliminary inquiry.Calculation models of corrugated basal body were proposed to analysis the longitudinal tensile deformation characteristics and bending lateral bearing characteristics. The formulas of longitudinal extension length and transversal flexural rigidity were calculated. Corrugated skin specimens reinforced by composite were made and experimental tests were done to prove the correctness of calculation models. On this basis, optimization work of corrugated skin specimens was carried out. The experimental results of optimal specimens indicated that longitudinal tensile deformation characteristics of optimal specimens were significantly increased and enough resistance against bending loads in transverse direction was inherited.A debice was designed and made to embed shape memory alloy (SMA) actuator in corrugated skin specimens to make skin posses active deformation ability. Specimens were made and driving experiment showed that skin can self-actuated revert because of the elasticity in elastic range. The velocity of shape recovery of skin was accelerated afer using thermoelectric chips. What is more, infrared temperature measurement system was developed to monitor the temperature variation of SMA and skin real-timely to ensure the stable and normal performance of the skins. And the development of infrared temperature measurement system provided the research foundation for deformation control system.Finally, cellular flexible skin was studied simply. Equivalent elastic modulus of x and y directions were deduced based onY model cellular unit in uniaxial stress. And tensile testing of specimens of cellular structure was performed.