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Abstract Wearable strain sensors for movement tracking are a promising paradigm to improve clinical care for patients with neurological or musculoskeletal conditions, with further applicability to athletic wear, virtual reality, and next‐generation game controllers. Clothing‐like wearable strain sensors can support these use cases, as the fabrics used for clothing are generally lightweight and breathable, and interface with the skin in a manner that is mechanically and thermally familiar. Herein, a fabric capacitive strain sensor is presented and integrated into everyday clothing to measure human motions. The sensor is made of thin layers of breathable fabrics and exhibits high strains (>90%), excellent cyclic stability (>5000 cycles), and high water vapor transmission rates (≈50 g/h m2), the latter of which allows for sweat evaporation, an essential parameter of comfort. The sensor's functionality is verified under conditions similar to those experienced on the surface of the human body (35°C and % relative humidity) and after washing with fabric detergent. In addition, the fabric sensor shows stable capacitance at excitation frequencies up to 1 MHz, facilitating its low‐cost implementation in the Arduino environment. Finally, as a proof of concept, multiple fabric sensors are seamlessly integrated with commercial activewear to collect movement data. With the prioritization of breathability (air permeability and water vapor transmission), the fabric sensor design presented herein paves the way for future comfortable, unobtrusive, and discrete sensory clothing.
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“Skin-like” fabric for personal moisture management
Personal moisture management fabrics that facilitate sweat transport away from the skin are highly desirable for wearer’s comfort and performance. Here, we demonstrate a “skin-like” directional liquid transport fabric, which enables continuous one-way liquid flow through spatially distributed channels acting like “sweating glands” yet repels external liquid contaminants. The water transmission rate can be 15 times greater than that of best commercial breathable fabrics. This exceptional property is achieved by creating gradient wettability channels across a predominantly superhydrophobic substrate. The flow directionality is explained by the Gibbs pinning criterion. The permeability, mechanical property, and abrasion resistance (up to 10,000 cycles) of the fabric were not affected by the treatment. In addition to functional clothing, this concept can be extended for developing materials for oil-water separation, wound dressing, geotechnical engineering, flexible microfluidics, and fuel cell membranes.
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- Award ID(s):
- 1719875
- PAR ID:
- 10148243
- Date Published:
- Journal Name:
- Science Advances
- Volume:
- 6
- Issue:
- 14
- ISSN:
- 2375-2548
- Page Range / eLocation ID:
- eaaz0013
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
-
Accepted Manuscript1.0
- Journal Article:
- https://doi.org/10.1126/sciadv.aaz0013
