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Abstract: 3D printing offers significant potential in creating highly customized interactive and functional objects. However, at present ability to manufacture functional objects is limited by available materials (e.g., various polymers) and their process properties. For instance, many functional objects need stronger materials which may be satisfied with metal printers. However, to create wholly interactive devices, we need both conductors and insulators to create wiring, and electronic components to complete circuits. Unfortunately, the single material nature of metal printing, and its inherent high temperatures, preclude this. Thus, in 3D printed devices, we have had a choice of strong materials, or embedded interactivity, but not both. In this paper, we introduce a set of techniques we call FiberWire, which leverages a new commercially available capability to 3D print carbon fiber composite objects. These objects are light weight and mechanically strong, and our techniques demonstrate a means to embed circuitry for interactive devices within them. With FiberWire, we describe a fabrication pipeline takes advantage of laser etching and fiber printing between layers of carbon-fiber composite to form low resistance conductors, thereby enabling the fabrication of electronics directly embedded into mechanically strong objects. Utilizing the fabrication pipeline, we show a range of sensor designs, their performance characterization on these new materials and finally three fully printed example object that are both interactive and mechanically strong -- a bicycle handle bar with interactive controls, a swing and impact sensing golf club and an interactive game controller (Figure 1).
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4D Printed Protein‐AuNR Nanocomposites with Photothermal Shape Recovery
Abstract 4D printing is the 3D printing of objects that change chemically or physically in response to an external stimulus over time. Photothermally responsive shape memory materials are attractive for their ability to undergo remote activation. While photothermal methods using gold nanorods (AuNRs) are used for shape recovery, 3D patterning of these materials into objects with complex geometries using degradable materials is not addressed. Here, the fabrication of 3D printed shape memory bioplastics with photo‐activated shape recovery is reported. Protein‐based nanocomposites based on bovine serum albumin (BSA), poly (ethylene glycol) diacrylate (PEGDA), and AuNRs are developed for vat photopolymerization. These 3D printed bioplastics are mechanically deformed under high loads, and the proteins served as mechano‐active elements that unfolded in an energy‐dissipating mechanism that prevented fracture of the thermoset. The bioplastic object maintained its metastable shape‐programmed state under ambient conditions. Subsequently, up to 99% shape recovery is achieved within 1 min of irradiation with near‐infrared (NIR) light. Mechanical characterization and small angle X‐ray scattering (SAXS) analysis suggest that the proteins mechanically unfold during the shape programming step and may refold during shape recovery. These composites are promising materials for the fabrication of biodegradable shape‐morphing devices for robotics and medicine.
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- PAR ID:
- 10483273
- Publisher / Repository:
- Wiley Blackwell (John Wiley & Sons)
- Date Published:
- Journal Name:
- Advanced Functional Materials
- ISSN:
- 1616-301X
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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