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The folding motion of an origami structure can be stopped at a non-flat position when two of its facets bind together. Such facet-binding will induce self-locking so that the overall origami structure can stay at a pre-specified configuration without the help of additional locking devices or actuators. This research investigates the designs of self-locking origami structures and the locking-induced kinematical and mechanical properties. We show that incorporating multiple cells of the same type but with different geometry could significantly enrich the self-locking origami pattern design. Meanwhile, it offers remarkable programmability to the kinematical properties of the selflocking origami structures, including the number and position of locking points, and the deformation range. Self-locking will also affect the mechanical characteristics of the origami structures. Experiments and finite element simulations reveal that the structural stiffness will experience a sudden jump with the occurrence of self-locking, inducing a piecewise stiffness profile. The results of this research would provide design guidelines for developing self-locking origami structures and metamaterials with excellent kinematical and stiffness characteristics, with many potential engineering applications.
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Axisymmetric blockfold origami: a non-flat-foldable Miura variant with self-locking mechanisms and enhanced stiffness
Origami foldcores, especially the blockfold cores, have emerged as promising components of high-performance sandwich composites. Inspired by the blockfold origami, we propose the axisymmetric blockfold origami (ABO), which is composed of both rectangular and trapezoidal panels. The ABO inherits the non-flat-foldability of the blockfold origami, and furthermore, displays self-locking mechanisms and enhanced stiffness. The geometry and folding kinematics of the ABO are formulated with respect to the geometric parameters and the folding angle of the assembly. The mathematical conditions are derived for the existence of self-locking mechanisms. We perform compression test simulations to demonstrate enhanced stiffness and increased load-bearing capacity. We find that the existence of rectangular panels not only dominates the non-flat-foldability of the ABO, but also contributes to the enhancement of the stiffness. Our results suggest the potential applications of the ABO for building load-bearing structures with rotational symmetry. Moreover, we discuss the prospects of designing tightly assembled multi-layered origami structures with prestress induced by the mismatch of successive layers to enlighten future research.
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- Award ID(s):
- 2323276
- PAR ID:
- 10590944
- Publisher / Repository:
- Royal Society
- Date Published:
- Journal Name:
- Proceedings of the Royal Society A: Mathematical, Physical and Engineering Sciences
- Volume:
- 480
- Issue:
- 2288
- ISSN:
- 1364-5021
- 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/10.1098/rspa.2023.0956
