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Abstract Magnetically actuated intelligent structures have shown great promise in various applications ranging from soft robotics to biomedical devices. One important type of structure involves embedding rigid magnets in polymer matrices, thanks to their simplicity in manufacturing and flexibility in structure design. However, accurately modeling their behavior remains challenging due to the strong nonlinear coupling between large deformation and spatially varying magnetic fields. To address this, we employ a fictitious magnetic charge method to transfer the magnetic forces and torques into surface traction under both uniform and nonuniform external magnetic actuation. We implement the proposed method in the commercial finite element software abaqus and validate it through a series of benchmark examples, which cover tuning the area of magneto-mechanical metamaterials, the shape changing of magnetic lattice structures, and the magnetic-field-driven buckling of cellular structures. Our approach enables accurate prediction of shape transformations in magnetically responsive structures, offering a practical tool for the design and optimization of future magneto-mechanical metamaterials and devices.
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Encoding reprogrammable properties into magneto-mechanical materials via topology optimization
Abstract The properties of materials and structures typically remain fixed after being designed and manufactured. There is a growing interest in systems with the capability of altering their behaviors without changing geometries or material constitutions, because such reprogrammable behaviors could unlock multiple functionalities within a single design. We introduce an optimization-driven approach, based on multi-objective magneto-mechanical topology optimization, to design magneto-active metamaterials and structures whose properties can be seamlessly reprogrammed by switching on and off the external stimuli fields. This optimized material system exhibits one response under pure mechanical loading, and switches to a distinct response under joint mechanical and magnetic stimuli. We discover and experimentally demonstrate magneto-mechanical metamaterials and metastructures that realize a wide range of reprogrammable responses, including multi-functional actuation responses, adaptable snap-buckling behaviors, switchable deformation modes, and tunable bistability. The proposed approach paves the way for promising applications such as magnetic actuators, soft robots, and energy harvesters.
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- PAR ID:
- 10412256
- Date Published:
- Journal Name:
- npj Computational Materials
- Volume:
- 9
- Issue:
- 1
- ISSN:
- 2057-3960
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
-
Accepted Manuscript
- Journal Article:
- https://doi.org/10.1038/s41524-023-00980-2
