Origami provides a flexible platform for constructing three-dimensional multi-stable mechanical metamaterials and structures. While possessing many interesting features originating from folding, the development of multi-stable origami structures is faced with tremendous demands for acquiring tunability and adaptability. Through an integration of origami folding with magnets, this research proposes a novel approach to synthesize and harness multi-stable
magneto-origami structures. Based on the stacked Miura-ori and the Kresling ori structures, we reveal that the embedded magnets could effectively tune the structure’s potential energy landscapes, which includes not only altering the position and the depth of the potential wells but essentially eliminating the intrinsic potential wells or generating new potential wells. Such magnet-induced evolutions of potential energy landscapes would accordingly change the origami structure’s stability profiles and the constitutive force–displacement relations. Based on proof-ofconcept prototypes with permeant magnets, the theoretically predicted effects of magnets are verified. The exploration is also extended to the dynamics realm. Numerical studies suggest that the incorporated magnets not only could translate the critical frequencies for achieving certain dynamical behaviors but also fundamentally adjust the frequency-amplitude relationship. Overall, this study shows that the proposed approach would provide a novel means to control the stability profile as well as the mechanics and dynamic characteristics of origami structures, and thus, inspire new innovations in designing adaptive mechanical metamaterials and structures.
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Exploring the dynamic characteristics of degree-4 vertex origami metamaterials
Origami-inspired mechanical metamaterials could exhibit
extraordinary properties that originate almost exclusively from
the intrinsic geometry of the constituent folds. While most of
current state of the art efforts have focused on the origami’s
static and quasi-static scenarios, this research explores the
dynamic characteristics of degree-4 vertex (4-vertex) origami
folding. Here we characterize the mechanics and dynamics of
two 4-vertex origami structures, one is a stacked Miura-ori
(SMO) structure with structural bistability, and the other is a
stacked single-collinear origami (SSCO) structure with lockinginduced
stiffness jump; they are the constituent units of the
corresponding origami metamaterials. In this research, we
theoretically model and numerically analyze their dynamic
responses under harmonic base excitations. For the SMO
structure, we use a third-order polynomial to approximate the
bistable stiffness profile, and numerical simulations reveal rich
phenomena including small-amplitude intrawell, largeamplitude
interwell, and chaotic oscillations. Spectrum analyses
reveal that the quadratic and cubic nonlinearities dominate the
intrawell oscillations and interwell oscillations, respectively.
For the SSCO structure, we use a piecewise constant function to
describe the stiffness jump, which gives rise to a frequencyamplitude
response with hardening nonlinearity characteristics.
Mainly two types of oscillations are observed, one with small
amplitude that coincides with the linear scenario because
locking is not triggered, and the other with large amplitude and
significant nonlinear characteristics. The method of averaging is
adopted to analytically predict the piecewise stiffness dynamics.
Overall, this research bridges the gap between the origami
quasi-static mechanics and origami folding dynamics, and paves
the way for further dynamic applications of origami-based
structures and metamaterials.
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- Award ID(s):
- 1634545
- NSF-PAR ID:
- 10197966
- Date Published:
- Journal Name:
- ASME section IX
- ISSN:
- 1486-7141
- Page Range / eLocation ID:
- 1-10
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
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Accepted Manuscript1.0
- Journal Article:
- https://doi.org/10.1115/SMASIS2017-3810
