Modeling of snapping composite shells with magnetically aligned bio-inspired reinforcements

Abstract

Materials capable of exhibiting inherent morphing are rare and typically reliant on chemical properties. The resulting diffusion-driven shape adaptability is slow and limited to specific environmental conditions. In contrast, natural composites, such as those found in carnivorous plants, have evolved hierarchical architectures displaying remarkably fast adaptation in response to environmental stimuli. These biological materials have inspired the fabrication of snapping composite shells through the careful design of the internal microstructure of synthetic materials by magnetic alignment of reinforcements. The ability to accurately model such programmable materials using finite element analysis (FEA) is necessary to facilitate the design optimization of the resulting structures. Using similar material parameters as explored in previous experimental studies, we employ nonlinear FEA to investigate the effects of introducing curvilinear spatially distributed micro-reinforcements on the deformation of a shell with an unusual bioinspired geometry. The FEA model is subject to experimental validation with magnetically aligned specimens. Comparison to a traditional [90/0] composite layup demonstrates the advantages of magnetically aligned reinforcements to achieve complex, snapping morphing structures with tailored characteristics.

Robotics: Science preceding science fiction

“…68 In composites in which magnetic microparticles are used as reinforcements and are distributed with predetermined orientations and positions, external magnetic fields (Figure 4c, bottom) have been used to control remotely the precise shaping of the robot and to drive its locomotion inside a phantom stomach. 69,70 Finally, internal stresses can be built within microstructured stiff composites to exploit nonlinear mechanisms such as buckling and multistability 45,71 (Figure 4d). Bistability in epoxy shells reinforced with long or short particles has been explored to achieve a combination of fast actuation and high actuation stresses (Figure 3b).…”

Modeling the effect of microstructure on elastic wave propagation in platelet-reinforced composites and ceramics

“…Biaxial reinforcement increases the strength and toughness in monolayers [31] and can induce morphing in bilayers with perpendicular directions of reinforcement [19,32].…”

Bioinspired Self-Shaping Clay Composites for Sustainable Development

“…The morphing of plants has been reproduced in synthetic materials by controlling their internal architecture with long fibers arranged into similar 0/90 or −45/45 layups [ 34 , 35 ]. Furthermore, recent works have been using short particulates in the form of microfibers and microplatelets to locally tune the architecture and achieve a larger design freedom and more shapes than long fibers can produce [ 2 , 36 , 37 ]. Bioinspired self-shaping in ceramic materials is scarce but has been demonstrated in technical alumina ceramics, and silica [ 1 , 38 ].…”