Progress on the Fabrication of Smart Textiles Based on Soft Strain Sensors

Abstract

<jats:p>The focus of this study is on strain sensing research and applications in smart textiles. Strain sensing is the measurement of fabric deformation by embedding a strain-sensitive material in it and subjecting it to stress. This paper presents an extensive classification of knitted textile strain sensors. Salient knitted strain sensor production parameters, such as conductive yarn choice, fabric structure, fabric structure deformation, and its relationship to strain signal extraction are discussed. The study concludes that producing yarn-based soft strain sensors for smart textile applications is viable. However, sensitive yarns with the right conductivity, count, and structural configuration are often unavailable. Work remains in the areas of efficient fabric deformation, signal extraction methods, development of sensor nodes, and robust experimental testing systems.</jats:p>

Review of development trends in smart shoe applications

“…A number of sensing technologies and data protocols generally for smart wears have been developed over the years. These sensing technologies include piezoelectricity (Akerfeldt et al , 2014), piezoresistive sensing (Huang et al , 2008), resistive sensing (Kim et al , 2018), impedance, capacitance, inductance (Christopoulos et al , 2014), triboelectric nanogenerator (Wang et al , 2023) and fiber optics (Fresnel reflection and fiber Bragg grating; Raji et al , 2019b). Others include ultrasonic sensing, Global Positioning System (GPS), radio frequency identification technology (RFID) information grid (Duroc and Tedjini, 2018), accelerometers, inertial measurement units (IMUs), Bluetooth for connectivity and reverse electrowetting and so on.…”

“…Resistive sensors function by detecting alterations in the structure of the sensitive region when it is exposed to stress. To design the sensitive region, conductive materials and resistive materials are set up with overlapping nanomaterials within a percolation network (a lattice constructed of a random mixture of conducting and nonconducting links) (Raji et al , 2019b).…”

“…Conductive materials such as carbon and its allotropes have been prominently featured materials for electrical conductivity related sensing technologies. Others include silver, silver nanowires, polymer optical fibers and stainless steel fibers and other conductive polymers (Raji et al , 2019b). In some cases, it expressly involves attachment of electronic circuits and electronic parts of electronic devices.…”

“…As such functions with high electrical energy demand might have to be fitted with energy generating systems to power or augment the battery systems being used. At present, electronic components required for signal processing systems often exhibit rigidity, limited washability, high cost, and in some cases, lack satisfactory aesthetic appeal (Raji et al , 2019b).…”

“…Currently, smart functionalities are present in baby wears (Cho et al, 2021), shirts, wrist watches, bras and vests (Raji et al, 2023). Air conditioning suits (warming and cooling) and massage bras are now popular trends (Raji et al, 2019b). However, at the moment, smart shoes are not as popular as other wearable devices such as smart watches or fitness trackers.…”