title: Extremely Elastic Wearable Carbon Nanotube Fiber Strain Sensor for Monitoring of Human Motion.
abstract: The increasing demand for wearable electronic devices has made the development of highly elastic strain sensors that can monitor various physical parameters an essential factor for realizing next generation electronics. Here, we report an ultrahigh stretchable and wearable device fabricated from dry-spun carbon nanotube (CNT) fibers. Stretching the highly oriented CNT fibers grown on a flexible substrate (Ecoflex) induces a constant decrease in the conductive pathways and contact areas between nanotubes depending on the stretching distance; this enables CNT fibers to behave as highly sensitive strain sensors. Owing to its unique structure and mechanism, this device can be stretched by over 900% while retaining high sensitivity, responsiveness, and durability. Furthermore, the device with biaxially oriented CNT fiber arrays shows independent cross-sensitivity, which facilitates simultaneous measurement of strains along multiple axes. We demonstrated potential applications of the proposed device, such as strain gauge, single and multiaxial detecting motion sensors. These devices can be incorporated into various motion detecting systems where their applications are limited to their strain.
authors.affiliation: †Department of Mechanical Engineering, Massachusetts Institute of Technology (MIT), 77 Massachusetts Avenue, Cambridge, Massachusetts 02139, United States.|‡Engineering Product Development, Singapore University of Technology and Design (SUTD), 20 Dover Drive, Singapore 138682, Singapore.
authors.forename: Seongwoo
authors.initials: S
authors.lastname: Ryu
authors.affiliation: †Department of Mechanical Engineering, Massachusetts Institute of Technology (MIT), 77 Massachusetts Avenue, Cambridge, Massachusetts 02139, United States.
authors.forename: Phillip
authors.initials: P
authors.lastname: Lee
authors.affiliation: †Department of Mechanical Engineering, Massachusetts Institute of Technology (MIT), 77 Massachusetts Avenue, Cambridge, Massachusetts 02139, United States.
authors.forename: Jeffrey B
authors.initials: JB
authors.lastname: Chou
authors.affiliation: †Department of Mechanical Engineering, Massachusetts Institute of Technology (MIT), 77 Massachusetts Avenue, Cambridge, Massachusetts 02139, United States.
authors.forename: Ruize
authors.initials: R
authors.lastname: Xu
authors.affiliation: ‡Engineering Product Development, Singapore University of Technology and Design (SUTD), 20 Dover Drive, Singapore 138682, Singapore.
authors.forename: Rong
authors.initials: R
authors.lastname: Zhao
authors.affiliation: †Department of Mechanical Engineering, Massachusetts Institute of Technology (MIT), 77 Massachusetts Avenue, Cambridge, Massachusetts 02139, United States.
authors.forename: Anastasios John
authors.initials: AJ
authors.lastname: Hart
authors.affiliation: †Department of Mechanical Engineering, Massachusetts Institute of Technology (MIT), 77 Massachusetts Avenue, Cambridge, Massachusetts 02139, United States.
authors.forename: Sang-Gook
authors.initials: SG
authors.lastname: Kim
mesh_terms: D003020:Clothing; D004548:Elasticity; D004581:Electronics / Q000295:instrumentation*; D006801:Humans; D008991:Monitoring, Physiologic / Q000295:instrumentation*; D009068:Movement; D036103:Nanotechnology / Q000295:instrumentation*; D037742:Nanotubes, Carbon / Q000737:chemistry*
chemical_list: D037742:Nanotubes, Carbon
keywords: carbon nanotube; elastic electrode; fiber; strain sensor; wearable device