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Morphing or reconfigurable structures potentially allow for previously unattainable vehicle performance by
permitting several optimized structures to be achieved using a single platform. The key to enabling this technology in
applications such as aircraft wings, nozzles, and control surfaces, are new engineered materials which can achieve the
necessary deformations but limit losses in parasitic actuation mass and structural efficiency (stiffness/weight). These
materials should exhibit precise control of deformation properties and provide high stiffness when exercised through
large deformations. In this work, we build upon previous efforts in segmented reinforcement variable stiffness
composites employing shape memory polymers to create prototype hybrid composite materials that combine the benefits
of cellular materials with those of discontinuous reinforcement composites. These composites help overcome two key
challenges for shearing wing skins: the resistance to out of plane buckling from actuation induced shear deformation,
and resistance to membrane deflections resulting from distributed aerodynamic pressure loading. We designed,
fabricated, and tested composite materials intended for shear deformation and address out of plane deflections in variable
area wing skins. Our designs are based on the kinematic engineering of reinforcement platelets such that desired
microstructural kinematics is achieved through prescribed boundary conditions. We achieve this kinematic control by
etching sheets of metallic reinforcement into regular patterns of platelets and connecting ligaments. This kinematic
engineering allows optimization of materials properties for a known deformation pathway. We use mechanical analysis
and full field photogrammetry to relate local scale kinematics and strains to global deformations for both axial tension
loading and shear loading with a pinned-diamond type fixture. The Poisson ratio of the kinematically engineered
composite is ~3x higher than prototypical orthotropic variable stiffness composites. This design allows us to create
composite materials that have high stiffness in the cold state below SMP Tg (4-14GPa) and yet achieve large composite
shear strains (5-20%) in the hot state (above SMP Tg).
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