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Asymmetric carbon fiber reinforced composites have shown immense potentials in adaptive structure applications such as morphing airfoils,1–4 and energy harvesters.5 Due to the unidirectional prepregs used for their fabrication and strongly nonlinear behaviors, these composite laminates can show significantly different load-displacement responses along with different loading directions. Moreover, asymmetric composites can exhibit bistability, offering a pathway to easily switch between different mechanical responses. This paper presents two switchable structure concepts based on asymmetric composites. The first concept exploits two distinct responses in the [0°/90° ] laminates in two perpendicular in-plane directions. Via a simple snap-through, such structure can switch between stiff and compliant. Preliminary experiments show that it can achieve close to 70:1 stiffness ratio between these two configurations. The second concept is a Kresling origami structure fabricated in a novel way using asymmetric fiber composites and 3D-printed flexible TPU material. Due to the asymmetric layup in their triangular composite facets, the Kresling structure can switch from a “foldable” configuration to a “locked” configuration. Axial compression and tension response for foldable and locked configurations are experimentally investigated. These two case studies suggest that there are still many untapped potentials in the asymmetric fiber composites for advanced and multi-functional structural applications.
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