Recent developments have shown that spatial structures devised from origami or low-dimensional rigid linkage mechanisms can be used to construct deployable arrays for antennas or satellites. Yet, some of these structures are limited to deployment in fixed planes or directions, or do not define straightforward processes for deployment. To surmount these limitations, this research introduces a reconfigurable single-degree-of-freedom spatial structure devised from a Kresling-inspired mechanism with integrated scissor arms. Analytical models are constructed to demonstrate compaction, deployment, and acoustic wave guiding capabilities of the proposed, modular structure. The influences of the geometric parameters on compaction, deployment, and scissor arm orientation are also explored, and reveal modular scissor arm behavior and large deployment-to-compaction area ratios. The acoustic wave guiding capabilities of the Kresling-inspired scissor structure are exemplified via a structure using spiral scissor arms, thereby proposing a novel concept for the construction of deployable wave guiding arrays. Experimental studies with model arrays complement the analytical findings of both the geometric reconfigurations and wave guiding functionality. Finally, out-of-plane configurations are depicted to demonstrate the three-dimensional shape change capabilities of the Kresling-inspired scissor structure. The results in this study encourage broader exploration of the interfaces between origami inspired structures and rigid linkage mechanisms.
Examine the Bending Stiffness of Generalized Kresling Modules for Robotic Manipulation
Via analytical modeling and experimental validation, this study examines the bending stiffness adaptation of bistable origami modules based on generalized Kresling pattern. These modules, which are the building blocks of an octopus-inspired robotic manipulator, can create a reconfigurable articulation via switching between their stable states. In this way, the manipulator can exhibit pseudo-linkage kinematics with lower control requirements and improved motion accuracy compared to completely soft manipulators. A key to achieving this reconfigurable articulation is that the underlying Kresling modules must show a sufficient difference in bending stiffness between their stable states. Therefore, this study aims to use both a nonlinear bar-hinge model and experimental testing to uncover the correlation between the module bending stiffness and the corresponding origami designs. The results show that the Kresling origami module can indeed exhibit a significant change in bending stiffness because of the reorientation of its triangular facets. That is, at one stable state, these facets align close to parallel to the longitudinal axis of the cylindrical-shaped module, so the module bending stiffness is relatively high and dominated by the facet stretching. However, at the other stable states, the triangular facets are orientated close to perpendicular to the longitudinal axis, so the bending stiffness is low and dominated by crease folding. The results of this study will provide the necessary design insights for constructing a fully functional manipulator with the desired articulation behavior.
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- NSF-PAR ID:
- 10224771
- Date Published:
- Journal Name:
- ASME 2020 International Design Engineering Technical Conferences and Computers and Information in Engineering Conference
- Volume:
- 10
- Page Range / eLocation ID:
- V010T10A077
- 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
- Conference Paper:
- https://doi.org/10.1115/DETC2020-22187
