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The purpose of this paper is to develop a capacitor fully integrated into a wearable textile fabric for the application on smart clothing.

A small capacitor with stainless steel yarns as the electrodes and poly-(3,4–ethylenedioxythiophene): polystryrene sulphonate (PEDOT:PSS) as the dielectric material has been made, integrated into a textile fabric. The electric performance of the capacitor was analyzed and compared with other kinds of electric capacitors.

The fabricated small, PEDOT:PSS capacitor could finally power a calculator for 37 s with the energy stored in it.

This finding is of an important significance for a further development on the capacitor with a better performance.

There is a developing interest in flexible sensors, especially in the new and intelligent generation of textiles. The purpose of this paper is to fabricate a flexible capacitive sensor on a PET fabric and to investigate some affecting factor on its performance.

PET fabric, coated with graphite or with graphite/PEDOT:PSS, was applied as electrodes. Two types of electrospun nanoweb layers from polyamide and polyvinyl alcohol polymers were used as dielectrics. Some factors including electrode area, fabric conductivity, fabric roughness, dielectric thickness, dielectric insulation type and vertical pressure were considered as independent variables. The capacity of the sensor and its detection threshold considered as the outcome (response) variables. Control samples were fabricated by using aluminum plates and cellulosic layer as electrodes and dielectric, respectively.

Results showed that post-coating with PEDOT:PSS would improve the conductivity of electrodes up to 300 Ω in comparison with just graphite-coated samples. It was also found that either by improving the conductivity or increasing the area of electrode plates the sensitivity of sample would be increased in pressure stimulating tests.

The fabric sensor showed remarkable response toward pressure with a lower detection threshold of 30mN/cm² (obtained capacity ~ 4×104 pF) in comparison with aluminum electrode sensors.

This review paper aims to introduce the inkjet printing as a tool for fabrication of flexible/wearable sensors. It summarizes inkjet printing techniques including various modes of operation, commonly used substrates and inks, commercially available inkjet printers and variables affecting the printing process. More focus is on the drop-on-demand printing mode, a strongly considered printing technique for patterning conductive lines on flexible and stretchable substrates. As inkjet-printed patterns are influenced by various variables related to its conductivity, resistivity, durability and dimensions of printed patterns, the main printing parameters (e.g. printing multilayers, inks sintering, surface treatment, cartridge specifications and printing process parameters) are reported. The embedded approaches of adding electronic components (e.g. surface-mounted and optoelectronic devices) to the stretchable circuit are also included.

In this paper, inkjet printing techniques for fabrication of flexible/stretchable circuits will be reviewed. Specifically, the various modes of operation, commonly used substrates and inks and variables affecting the printing process will be presented. Next, examples of inkjet-printed electronic devices will be demonstrated. These devices will be compared to their rigid counterpart in terms of ease of implementation and electrical behavior for wearable sensor applications. Finally, a summary of key findings and future research opportunities will be presented.

In conclusion, it is evident that the technology of inkjet printing is becoming a competitor to traditional lithography fabrication techniques, as it has the advantage of being low cost and less complex. In particular, this technique has demonstrated great capabilities in the area of flexible/stretchable electronics and sensors. Various inkjet printing methods have been presented with emphasis on their principle of operation and their commercial availability. In addition, the components of a general inkjet printing process have been discussed in details. Several factors affect the resulting printed patterns in terms of conductivity, resistivity, durability and geometry.

The paper focuses on flexible/stretchable optoelectronic devices which could be implemented in stretchable circuits. Furthermore, the importance and challenges related to printing highly conductive and highly stretchable lines, as well as reliable electronic devices, and interfacing them with external circuitry for power transmission, data acquisition and signal conditioning have been highlighted and discussed. Although several fabrication techniques have been recently developed to allow patterning conductive lines on a rubber substrate, the fabrication of fully stretchable wearable sensors remains limited which needs future research in this area for the advancement of wearable sensors.

This paper aims to study the working principle of the capacitive pressure sensor and explore the distribution of pressure acting on the surface of the capacitor. Herein, a kind of high sensitivity capacitive pressure sensor was prepared by overlaying carbon fibers (CFs) on the surfaces of the thermoplastic elastomer (TPE), the TPE with high elasticity is a dielectric elastomer for the sensor and the CFs with excellent electrical conductivity were designed as the conductor.

Due to the excellent mechanical properties and electrical conductivity of CFs, it was designed as the conductor layer for the TPE/CFs capacitive pressure sensor via laminating CFs on the surfaces of the columnar TPE. Then, a ‘#' type structure of the capacitive pressure sensor was designed and fabricated.

The ‘#' type of capacitive pressure sensor of TPE/CFs composite was obtained in high sensitivity with a gauge factor of 2.77. Furthermore, the change of gauge factor values of the sensor under 10 per cent of applied strains was repeated for 1,000 cycles, indicating its outstanding sensing stability. Moreover, the ‘#' type capacitive pressure sensor of TPE/CFs was consisted of several capacitor arrays via laminating CFs, which could detect the distribution of pressure.

The TPE/CFs capacitive pressure sensor was easily fabricated with high sensitivity and quick responsiveness, which is desirably applied in wearable electronics, robots, medical devices, etc.

The outcome of this study will help to fabricate capacitive pressure sensors with high sensitivity and outstanding sensing stability.

Embroidery as a textile embellishment technique plays an important role in people's daily life. Esthetic embroidery artworks possess cultural values. With the development of robotics and artificial intelligence (AI), these technologies have been studied and applied in the embroidery process. This study aims to survey how these technologies facilitate embroidery from different aspects.

This paper surveys how the technologies of robotics and AI are applied in the embroidery field. The applications are mainly reviewed from three aspects: computerized robotic embroidery systems has been widely used for the mass production of embroidered textiles, the advanced technological systems and techniques have greatly facilitated the development of smart textiles and the artificial intelligence plays an important role in the inheritance, innovation and protection of traditional handicraft artwork of embroidery.

The programmable robotic embroidery machines have greatly improved the production efficiency of embroidered textiles and promoted the development of electronic textiles. The AI, mainly the deep learning technology, brings significant benefits to esthetic embroidery creation. Technology-based embroidery has become a hot research topic in the field of textiles.

This paper summarizes the application of robotics and AI technologies in the field of embroidery, which provides readers a comprehensive and systematic understanding about the research progress of modern technology-oriented embroidery. This helps readers gain inspiration from the technology perspectives.

In this paper an electrochemical cell is developed to test and follow up the quality of electrodes made of knitted, woven and non‐woven conductive textile material.

This cell is constructed of two electrodes planarly positioned against each other using the support of a PVC tube and two PVC plates. Between the electrodes and the electrolyte special membranes are placed that simulate the human skin.

This research is a preliminary start of a study to investigate and understand the behaviour of textile electrodes and to gain insight in the inter‐phases electrode‐electrolyte and electrode‐skin‐electrolyte in order to be able to model the system and to use it for detection of parameters and body conditions.

As pointed out earlier, a lot of work still needs to be done but the preliminary work shows that promising possibilities can be offered.

Simulation of human body behaviour during sweat production measured by textile electrodes.

This paper seeks to pursue the research of different types of sensors suitable for positioning edge accuracy of textile material.

A measuring device is used to install different types of sensors on the slide holders and to change their interspace as well as the space between the sensors and textile fabric.

The new measuring equipment has been established.

Only the results of woven fabric measurement are analyzed in this paper, while the results of knitted and nonwoven fabric measurement will be elaborated in the future papers.

The measuring equipment is original.

Recent developments in wearable technologies have paved the way for continuous monitoring of the electrocardiogram (ECG) signal, without the need for any laboratory settings. A number of wearable sensors ranging from wet electrode sensors to dry sensors, textile-based sensors, knitted integrated sensors (KIS) and planar fashionable circuit boards are used in ECG measurement. The purpose of this study is to carry out a comparative study of the different sensors used for ECG measurements. The current challenges faced in developing wearable ECG sensors are also reviewed.

This study carries out a comparative analysis of different wearable ECG sensors on the basis of four important aspects: materials and methods used to develop the sensors, working principle, implementation and performance. Each of the aspects has been reviewed with regard to the main types of wearable ECG sensors available.

A comparative study of the sensors helps understand the differences in their operating principles. While some sensors may have a higher efficiency, the others might ensure more user comfort. It is important to strike the right balance between the various aspects influencing the sensor performance.

Wearable ECG sensors have revolutionized the world of ambulatory ECG monitoring and helped in the treatment of many cardiovascular diseases. A comparative study of the available technologies will help both doctors and researchers gain an understanding of the shortcomings in the existing systems.

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.