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The purpose of this research is to propose a flexible sensor with a weft-knitted float stitch structure and to explore knitting techniques that allow conductive yarns to be skin-tight and less exposed, reducing production processes and increasing productivity. Study its electrical conductivity in different yarn materials, knit processes and deformation ranges. The analysis is compared to provide some basis for the design of the electrodes.

The method includes five operations: (1) Analysis of the morphological appearance, tensile variation, fiber material properties and electrical conductivity of high-elastic and filament silver-plated conductive yarns. (2) Based on the knitting process of the floating yarn structure, three-dimensional modeling of the flexible sensor was carried out to explore the influence of knitting process changes on appearance characteristics. (3) The fabric samples are knitted by different silver-plated conductive yarns with different structures. Processing of experimental samples to finished size by advance shrinkage. (4) Measure the resistance of the experimental sample after the machine has been lowered and after pre-shrinking. Use the stretching machine to simulate a wearing experiment and measure the change in resistance of the sample in the 0–15% stretching range. (5) Analyze the influence factors on the conductive performance of the flexible sensor to determine whether it is suitable for textile flexible sensors.

For the float knitted flexible sensors, the floating wire projection is influenced by the elasticity of the fabric and the length of the floating wire. Compared to the plain knitted flexible sensors, it has less resistance variation and better electrical properties, making it suitable for making electrodes for textile structures. In addition, the knitting method is integrated with the intelligent monitoring clothing, which saves the process for the integration of the flexible sensor, realizes positioning and fixed-point knitting.

The sensor technology of the designed weft-knitted float structure is varied and can be freely combined and designed in a wide range. Within the good electrical conductivity, the flexible sensor can realize integrated knitting, positioning monitoring, integrating into the appearance of clothing. It can also focus on the wearing experience of wearable products so that the appearance of the monitoring clothing is close to the clothes we wear in our daily life.

In this paper, an integrated positioning knitting flexible sensor based on the weft knitting float structure is studied. The improved knitting process allows the sensing contact surface to be close to the skin and reduces the integration process. The relationship between the exposure of the silver-plated yarn on the clothing surface and the electrical conductivity is analyzed. Within a certain conductive performance, reduces the exposed area of the conductive yarn on the clothing surface and proposes a design reference for the flexible sensor appearance.

The use of conductive yarns or wires to design and construct fabric-based strain sensors is a research area that is gaining much attention in recent years. This is based on a profound theory that conductive yarns will have a variation in resistance if subjected to tension. What is not clear is to which types of conductive yarns are most suited to delivering the right sensitivity. The purpose of this paper is to look at strain sensors knitted with conductive composite and coated yarns which include core spun, blended, coated and commingled yarns. The conductive components are stainless steel and silver coating respectively with polyester as the nonconductive part. Using Stoll CMS 530 flat knitting machine, five samples each were knitted with the mentioned yarn categories using 1×1 rib structure. Sensitivity tests were carried out on the samples. Piezoresistive response of the samples reveals that yarns with heterogeneous external structures showed both an increase and a decrease in resistance, whereas those with homogenous structures responded linearly to stress. Stainless steel based yarns also had higher piezoresistive range compared to the silver-coated ones. However, comparing all the knitted samples, silver-coated yarn (SCY) proved to be more suitable for strain sensor as its response to tension was unidirectional with an appreciable range of change in resistance.

Conductive composite yarns, namely, core spun yarn (CSY1), core spun yarn (CSY2), silver-coated blended yarn (SCBY), staple fiber blended yarn (SFBY) and commingled yarn (CMY) were sourced based on specifications and used to knit strain sensor samples. Electro-mechanical properties were investigated by stretching on a fabric tensile machine to ascertain their suitability for a textile strain sensor.

In order to generate usable signal for a strain sensor for a conductive yarn, it must have persistent and consistent conductive links, both externally and internally. In the case of composite yarns such as SFBY, SCBY and CMY where there were no consistent alignment and inter-yarn contact, resistance change fluctuated. Among all six different types of yarns used, SCY presented the most suitable result as its response to tension was unidirectional with an appreciable range of change in resistance.

This is an original research carried out by the authors who studied the electro-mechanical properties of some composite conductive yarns that have not been studied before in textile strain sensor research. Detailed research methods, results and interpretation of the results have thus been presented.

In this research project, electrical conductive yarns were knitted together with 100 per cent cotton yarns to create knitted fabrics that would be used as electromagnetic (EM) shielding materials. The paper aims to discuss these issues.

1×1 plain fabrics knitted on double-bed hand knitting machines of five and seven gauges. Several strands of the cotton yarns were used together in order to knit samples with good handling properties. The electrical conductive yarn has six plies and each ply has 29 filaments with Naño-coating of silver and having an electrical resistance of 4 Ohms per 100 mm and a count of 96 Tex. The knitted fabrics have similar texture but vary in term of specific weight, fabric density, loop length, Tex, tightness factor, thickness and electrical conductivity. These variations affected the properties of the fabrics, determining factors of a good shielding or not. A special designed Faraday cage was built to measure the EMSE of each knitted fabrics. The EM waves were sent through the signal generator at different frequencies as from 400 to 1,100 MHz and with three different power inputs of 10, 20 and 30 dBm. EMSE measurements were also carried out after the knitted samples were rotated clockwise.

Good EMSE shielding results were achieved with the knitted samples, however in this study it was found that different knitted fabrics shielded better at specific frequencies and power inputs.

Knitted fabrics can be used to develop comfortable garments that can be used to shield EM waves and protect the wearer.

The choice of using the conductive yarns is exclusive. In addition the EMSE were measured with fabrics knitted in the same structure but on different knitting machine gauge. Three different power inputs were considered and EMSE measurements were taken using frequencies as from 400 to 1,100 MHz. A new method for measuring the electrical resistance on the knitted fabrics and the method used for measuring the EMSE for each knitted fabric were considered.

This work seeks to analyze the heat transfer phenomena of anisotropic thermal conductivity fabrics containing electric conductive yarns.

A numerical program, based on a spectral element method, is used to assess the heating fabric with a temperature control model. The study determines suitable parameters for the fabric by evaluating the temperature uniformity on the fabric surface. Effective thermal conductivities of the fabric are obtained by comparing the experimental and numerical results with each other, using a nonlinear least‐square fitting method.

The results indicate that employing high effective thermal conductivity of non‐electric conductive yarns in a direction perpendicular to electric conductive yarns helps to increase temperature uniformity. However, the effect of the high effective thermal conductivity of electric conductive yarns is not evident. Adopting a short distance between the electric conductive yarns and a thick fabric is also beneficial in increasing temperature uniformity. If the heating fabric is applied in a place where there is easy energy transfer between the surface of the fabric and moving air, collocation with high heating power is needed to maintain the temperature. Choosing an appropriate heating source is essential when considering temperature uniformity and energy savings using a temperature controller.

The findings will be useful in the design of heating fabrics.

Flexible light-emitting textile display is designed with floats for electronic elements covering and electronic contacts insulation what at the same time provides an opportunity to develop aesthetic design of the display in the single piece construction of material. The paper aims to discuss these issues.

Display consists of interwoven electrically conductive yarns, non-conductive yarns and SMD LEDs connected to conductive yarns. Industrial jacquard weaving machine have been used, weave patterns were designed in PC-Edit software.

Weave can be used as a tool to build and evolve electrotextile. Exploring weaving techniques and perceiving electronic circuit as a weave pattern, new approaches can be developed in electrotextile design field.

Connections of electronic elements and conductive textile materials still is actual problem what should be explored in further research.

Flexible light emitting textile display can be used as output interface integrated into communication clothing by representing different animated images directly on clothing. Display also can be used for accessories, room and auto interior etc. applications.

Paper describes method of light source integration directly into textile structure, combining functional and visual design of textile display.

In recent years, interdisciplinary studies have been the mainstream in research discourses and practices. Depending on the degree of integration, the combination of electronics and textiles can be divided into three categories: wearable electronics, textronics and fibertronics. This paper discusses the development of cotton-wrapped nichrome yarn, copper core conductive yarn and optical core conductive yarn in different diameters for the production of nichrome fabric, copper core conductive fabric, optical core conductive fabric and teleintimation fabric. The yarn and the fabric were tested by a test rig especially developed for this research work. This work provides a methodology of developing conductive yarn and fabric for the development of wearable electronic products in terms of user acceptability.

The purpose of this paper is to investigate the thermal transfer properties of electric heating fabric system which contains heating units or conductive yarns by numerical simulation, in order to optimize and evaluate the thermal performance of heating clothing.

Two kinds of FEM models are created by ANSYS system: macro-scale models of the fabrics system with heating units and air layer; and meso-scale models of the plain-woven fabrics were established embedded with the stainless yarns. In the macro-scale model, the interior and surface temperature field distribution were simulated and analyzed based on different heating unit size, heating power, heating region, air layer thickness and ambient temperature. For meso-scale models, the effects of the conductive yarns temperature, covering fabrics and pore-filling material on the temperature field distribution were simulated and analyzed.

With the increasing of the air layer thickness or the effective conductivity, the heat transfer along the direction of fabric thickness decreases gradually. The heat transfer along the fabric plane can be increased by dispersing the heating region. With the increasing of the conductive yarns’ temperature or the covering fabrics’ conductivity, the heat transfer distance along the fabric warp direction can be increased. Filling the internal pores of the fabric with 10 wt% SiC/TPU hybrid materials can effectively increase the in-plane heat transfer and improve the temperature uniformity on the surface of heated fabrics.

The finite element method was used to establish the simulation models of the heating fabric systems. The influence of several parameters on the thermal performance was analyzed and discussed, as well as the internal and external temperature distribution in the macro and micro scales models.

The purpose of this paper is to develop textile-based transcutaneous electrical nerve stimulation (TENS) electrodes using conductive yarn to bring a solution to uncomfortable feelings and hygiene problems of conventional conductive hydrogel electrodes. It proposes washing process, resistance measurements and subjective tests to evaluate the performance of the developed textile-based electrode.

In this study, six different textile electrode pairs were designed and produced with different patterns. Designed electrodes were washed for ten times. In order to evaluate the effect of pattern differences and washing process on electrode performances, two different tests were realized before and after washing. The first of these tests is resistance measurement with a multimeter, and the second one is subjective test carried out on subjects.

The results obtained from resistance measurements indicated that the pattern differences cause resistance values of electrodes to change. It is reported that subjects had electrical stimulation from all electrode samples in conducted trials and it is noticed that washing process does not cause any stimulation problems.

In this study, textile-based TENS electrodes having different patterns were produced by machine stitching technique and their long-term usage behaviors were examined with repeated washing processes and trials on the subjects.

This paper aims to study the possibility of electroplating copper coatings on chemically and chemical-galvanically nickel-plated acrylic fibers, to be further processed into yarn, fabrics, knitwear and nonwoven materials.

Electrically conductive fibers with different copper contents have been obtained, and the effect of electrolyte pH, its composition, current strength at the first and second cathodes, as well as the metallization time on the electrophysical, physical and mechanical properties of copper-containing fibers, has been studied.

The studies have shown that with an increase in the copper content, the electrical conductivity, the uniformity of the coating and the uniformity of the electrophysical properties (for chemical-galvanically nickel-plated fiber) increase. In the case of copper plating of chemically nickel-plated fiber, the coefficient of variation in electrical resistance increases with increasing plating time, even though the copper content increases, and the coefficient of variation in copper content and electrical resistance decreases. The physical and mechanical properties of copper-containing fibers differ slightly from the original (subjected to copper plating) and industrial Nitron fibers. With copper plating, the strength of the fiber practically does not decrease, and the elongation decreases somewhat, compared with the mass-produced Nitron fiber.

The physical and mechanical properties of copper-containing fibers are quite high, which makes it possible to be successfully further processed into yarn, fabrics, knitwear and nonwoven materials.

Electronic textiles are a major new development in the field of smart technology. There are many potential applications for electrically active textiles (EAT). The purpose of this paper is to present state‐of‐the‐art knitted switches based on EAT technology.

The switches operate with double electrodes, and they are designed to be operated by a human finger, with or without a glove. In this study, these switches were manufactured based on EAT technology by generating conductive areas as electrodes.

A custom‐made impedance analyzer was developed to identify the electrical characteristics of the switches. The deriving circuits were designed to operate the switches according to their impedance characteristics.

The switch working with glove and bare hand is novel.