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A self-powered, and self-actuating lithium ion battery (LIB) has the potential to achieve large deformation while still maintaining actuation force. The energy storage capability allows for continual actuation without an external power source once charged. Reshaping the actuator requires a nonuniform distribution of charge and/or bending stiffness. Spatially varying the state of charge and bending stiffness along the length of a segmented unimorph configuration have the effect of improving the tailorability of the deformed actuator. In this paper, an analytical model is developed to predict the actuation properties of the segmented unimorph beam to determine its usefulness as an actuator. The model predicts the free deflection, blocked deflection, and blocked force at the tip as a function of spatially varying state of charge and bending stiffness. The main contribution of the paper is the development of blocked deflection over the length of the segmented unimorph, which has not yet been considered in the literature. The model is verified using experimental data and commercial finite element analysis.
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Peeling of finite-length elastica on Winkler foundation until complete detachment
Quasi-static peeling of a finite-length, flexible, horizontal beam (strip, thin film) from a horizontal substrate is considered. The displaced end of the beam is subjected to an upward deflection or to a rotation. The action of the adhesive is modeled as a Winkler foundation, and debonding is based on the common fracture mechanics approach. The behavior is examined from the application of loading to the initiation of peeling and then to complete detachment of the beam from the substrate. During at least a portion of the debonding process, the model corresponds to what traditionally has been considered a short beam on an elastic foundation. In the analysis, the beam is modeled as an elastica, so that bending is paramount and large displacements are allowed. The effects of the relative foundation stiffness to the beam bending stiffness, the work of adhesion, and the length, self-weight, extensibility, and initial unbonded length of the beam are investigated. In addition, experiments are conducted to complement the analysis.
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- Award ID(s):
- 2119105
- PAR ID:
- 10536091
- Publisher / Repository:
- Elsevier
- Date Published:
- Journal Name:
- International Journal of Solids and Structures
- Volume:
- 256
- Issue:
- C
- ISSN:
- 0020-7683
- Page Range / eLocation ID:
- 111944
- 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/10.1016/j.ijsolstr.2022.111944
