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Abstract Stretchable conductive materials have attracted great attention due to their potential applications as strain sensors, wearable electronics, soft robotics, and medical devices. The fabrication of these materials with customized object geometries is desirable, but the methods to achieve them are still highly limited. Additive manufacturing via vat photopolymerization can generate sophisticated object geometries, but there is still a significant need to print with materials that afford improved conductivity, mechanical properties, elastic recovery, and durability. Herein, stretchable strain sensors with a range of 3D printed designs are reported using vat photopolymerization. Ionic liquid resins are optimized for their printability using Sudan‐I as a photoabsorber and used to fabricate 3D objects that are subjected to compression, stretching, and bending loads that are detected as real‐time changes in current. Additionally, the self‐adhesive nature of these materials enables mechanically damaged structures to be mended together to regain its function as a strain sensor. These ionic liquid resins are compatible with commercial 3D printers, which enhances their applicability for on‐demand production of customized devices.
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Thermally Drawn Stretchable Electrical and Optical Fiber Sensors for Multimodal Extreme Deformation Sensing
Abstract Highly stretchable fiber sensors have attracted significant interest recently due to their applications in wearable electronics, human–machine interfaces, and biomedical implantable devices. Here, a scalable approach for fabricating stretchable multifunctional electrical and optical fiber sensors using a thermal drawing process is reported. The fiber sensors can sustain at least 580% strain and up to 750% strain with a helix structure. The electrical fiber sensor simultaneously exhibits ultrahigh stretchability (400%), high gauge factors (≈1960), and excellent durability during 1000 stretching and bending cycles. It is also shown that the stretchable step‐index optical fibers facilitate detection of bending and stretching deformation through changes in the light transmission. By combining both electrical and optical detection schemes, multifunctional fibers can be used for quantifying and distinguishing multimodal deformations such as bending and stretching. The fibers’ utility and functionality in sensing and control applications are demonstrated in a smart glove for controlling a virtual hand model, a wrist brace for wrist motion tracking, fiber meshes for strain mapping, and real‐time monitoring of multiaxial expansion and shrinkage of porcine bladders. These results demonstrate that the fiber sensors can be promising candidates for smart textiles, robotics, prosthetics, and biomedical implantable devices.
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- Award ID(s):
- 1847436
- PAR ID:
- 10452605
- Publisher / Repository:
- Wiley Blackwell (John Wiley & Sons)
- Date Published:
- Journal Name:
- Advanced Optical Materials
- Volume:
- 9
- Issue:
- 6
- ISSN:
- 2195-1071
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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