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Abstract Architected materials exhibit unique properties and functionalities based on the geometric arrangement of their constituent materials. In most cases, these parameters are fixed, requiring that the system be redesigned and reconstructed if different properties are desired. Both stimuli‐responsive materials and modular designs have been used to enable re‐programmable properties in the past, but often have limitations, such as the need for a continuous application of external stimuli or power, or unwanted global morphing. In this study, a locally stable anti‐tetra chiral (LSAT) metamaterial is introduced consisting of independently multistable units that can deform and change state without inducing changes in the global morphology. Adjacent cells are only weakly coupled, allowing the collective metamaterial to be switched between many different possible states. Local bistability enables re‐programmable heterogeneity, such as the snapping of cells along an edge or diagonally within the architected material. Utilizing finite element analysis (FEA), the influence of key geometric parameters on the re‐programmability of the metamaterials is systematically investigated. The effect of these parameters on properties such as shear stiffness, Poisson's ratio, and vibration are also investigated using experimental prototypes. This re‐programmable metamaterial promises to expand the design space for mechanical systems, with potential applications in non‐traditional computation, robotic actuation, and adaptive structures.
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Programming of Nonlinear Heterogeneous Metamaterial for Shock and Vibration
Abstract A digitally encoded mechanical metamaterial utilizing selective insertion of rigid elements into an elastomeric matrix achieves programmable stiffness based on geometric patterns. Beyond the linear behavior, interests are developed towards the nonlinear stiffness region to extend the application of such metamaterials from vibration isolation to shock mitigation. A 12-unit-cell prototype is constructed and experimentally characterized under compression and drop tests, yielding the stress-strain curves and energy absorption capabilities of all independent geometric patterns identified, respectively, with validation by finite-element analysis. The versatility of the metamaterial is illustrated via a categorization of its pattern-dependent responses.
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- Award ID(s):
- 2145803
- PAR ID:
- 10571593
- Publisher / Repository:
- American Society of Mechanical Engineers
- Date Published:
- ISBN:
- 978-0-7918-8832-2
- Format(s):
- Medium: X
- Location:
- Atlanta, Georgia, USA
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
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Accepted Manuscript1.0
- Conference Paper:
- https://doi.org/10.1115/SMASIS2024-141593
