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Gait analysis provides a convenient strategy for the diagnosis and rehabilitation assessment of diseases of skeletal, muscular, and neurological systems. However, challenges remain in current gait recognition methods due to the drawbacks of complex systems, high cost, affecting natural gait, and one‐size‐fits‐all model. Here, a highly integrated gait recognition system composed of a self‐powered multi‐point body motion sensing network (SMN) based on full textile structure is demonstrated. By combining of newly developed energy harvesting technology of triboelectric nanogenerator (TENG) and traditional textile manufacturing process, SMN not only ensures high pressure response sensitivity up to 1.5 V kPa−1, but also is endowed with several good properties, such as full flexibility, excellent breathability (165 mm s−1), and good moisture permeability (318 g m−2 h−1). By using machine learning to analyze periodic signals and dynamic parameters of limbs swing, the gait recognition system exhibits a high accuracy of 96.7% of five pathological gaits. In addition, a customizable auxiliary rehabilitation exercise system that monitors the extent of the patient's rehabilitation exercise is developed to observe the patient's condition and instruct timely recovery training. The machine learning‐assisted SMN can provide a feasible solution for disease diagnosis and personalized rehabilitation of the patients. [ABSTRACT FROM AUTHOR]

The tribovoltaic effect is the direct‐current (DC) output that results from sliding a p‐type semiconductor on top of an n‐type semiconductor, and it is caused by the electron–hole pairs generated However, the rigid structure of traditional semiconductor limits its potential application in wearable fields. Here, p–type and n–type fabric with semiconductor properties are prepared by doping small organic molecules of cetyltrimethylammonium bromide and sodium dodecylbenzene sulfonate on the carbon atoms of single–wall carbon nanotubes (SWCNTs), and three all‐fabric direct‐current triboelectric nanogenerators based on the tribovoltaic effect (AFDC‐TENG) are developed , which exhibit high flexibility, satisfactory comfort, and stable DC output. In addition, the effects of structural parameters and environmental factors on the electrical output of AFDC‐TENG are systematically discussed. The output voltage, current, and power density of p‐type AFDC‐TENG can reach 0.2 V, 0.29 µA, and 45.5 mV m−2 at a maximum speed of 0.2 m s−1 and a sliding frequency of 1 Hz, respectively. This work proposes a simple and scalable design form for all‐fabric DC power supply devices, which has potential applications in the future micro/nano energy or self‐powered flexible sensors. [ABSTRACT FROM AUTHOR]

Triboelectric power textile (TPT) that can harvest widespread but always neglected human biomechanical energy is considered a promising and reliable energy source for wearable electronics. However, the alternating current and high impedance of triboelectric nanogenerators as well as the meager electrical output caused by the properties of the textile itself greatly restrict its practical applications. Here, an autonomous power textile with practical application value, which consists of a high‐output direct‐current TPT (DC‐TPT) and a miniaturized energy management module (EMM), is achieved for continuous operation of wearable and mobile electronics. The home‐preparable multiarray DC‐TPT can harvest transferred charge of 5.5 µC per cycle with nine repeating units. Moreover, it is found that incorrect sewing positions of the polytetrafluoroethylene (PTFE) yarn change the working mechanism with a decreased DC output. The EMM with energy conversion efficiency of 82.6% can reduce the impedance of DC‐TPT from 200 to 1.6 MΩ. With its powerful assistance, the watch can work continuously for 172 s just by manually sliding the DC‐TPT 1.6 s on an arm, and wireless signals can be transmitted to 281 m away after sliding for 2 min. Various widely used electronics can also be easily and continuously driven. [ABSTRACT FROM AUTHOR]

Electromagnetic radiation, as one of the public hazards that injures human health and information safety, shall be shielded from the ambient environment. Here, by the virtue of polypyrrole polymerized polyamide yarns and silicone rubber, a yarn‐based electromagnetic shielding‐triboelectric nanogenerator (EMS‐TENG) equipped with sensing ability is presented, which not only generates electricity from harvesting body motion energy but also serves as EMS to prevent electromagnetic interference. With the aid of knitting method, the developed EMS‐TENG fabric exhibits the EMS effectiveness of 32.49 dB in 8.2–12.5 GHz and achieves a maximum instantaneous peak power density of 142.27 µW m−1. Furthermore, a real‐time human‐interactive system is developed by adopting the Internet of Things technology and EMS‐TENG sensor. Based on the above, a simulated intelligent calculator with multiplication and division function is proposed, which can successfully translate electronic signals to digital numbers. With energy harvesting and self‐powered sensing abilities, the EMS‐TENG can convert mechanical energy into electrical signals from human movements. Looking forward, the EMS‐TENG spurs an innovative technique toward a self‐powered human‐interactive sensing and functional protective textile for next‐generation intelligent wearable applications. [ABSTRACT FROM AUTHOR]

Industrialization and anthropogenic activities are expected and unavoidable to consummate the current resources of humankind, which also lead to accidents in the laboratory, chemical plants, or other high risk areas that cause severe burns, or even casualties. Increased casualties in such accidents are due to inappropriate safety measures and prevention. Here, a smart anti‐chemical protective suit with a bio‐motion energy harvesting and self‐powered safety monitoring system is demonstrated, which can protect the body from chemical harm, detect sudden chemical spills, monitor human real‐time living signals, and trigger alarms in an emergency. Particularly, a fabric triboelectric nanogenerator (F‐TENG), which is fabricated by the all‐fiber single‐electrode triboelectric nanogenerator yarn (SETY), works as the basic elements of the intelligent suit. The SETY with core‐shell structured design shows a high sensitivity to the corrosive liquids including acids and alkalis. Furthermore, the working principle of the yarn based nanogenerator that is powered by contacting with acid liquid droplets is demonstrated for the first time. In addition, discretionary thickness, permeability, and any other functionalities are also achieved by taking advantage of the fabric structure. This self‐powered smart anti‐chemical protective suit equipped with a real time monitoring system will benefit the wearer who works in a very high‐risk environment. [ABSTRACT FROM AUTHOR]

Human respiration is an indispensable physiological behavior of the body, which is an important indicator to evaluate health status, especially for sleep‐related diseases. A real‐time respiratory monitoring and sleep breathing detecting system with convenience, high sensitivity, simple fabrication, and wearing comfort still remains a challenge and urgently desirable. Here, a breathable, highly sensitive, and self‐powered electronic skin (e‐skin) based on a triboelectric nanogenerator (TENG) is reported for real‐time respiratory monitoring and obstructive sleep apnea‐hypopnea syndrome (OSAHS) diagnosis. By using multilayer polyacrylonitrile and "polyamide 66" nanofibers as the contact pairs, and deposited gold as the electrodes, a contact‐separation type of TENG‐based all‐nanofiber e‐skin is developed. The e‐skin has a peak power density of 330 mW m−2, high pressure sensitivity of 0.217 kPa−1, excellent working stability, and good air permeability. Therefore, the e‐skin is simultaneously capable of energy autonomy and accurate real‐time subtle respiration monitoring. Meanwhile, a self‐powered diagnostic system for real‐time detection and severity evaluation of obstructive sleep apnea‐hypopnea syndrome are further developed to prevent the occurrence of OSAHS, delay its development, and improve sleep quality. This study hopes to pave a new and practical pathway for real‐time respiration monitoring and sleep breathing diseases clinical detection. [ABSTRACT FROM AUTHOR]

Wearable, flexible, and even stretchable tactile sensors, such as various types of electronic skin, have attracted extensive attention, which can adapt to complex and irregular surfaces, maximize the matching of wearable devices, and conformally apply onto human organs. However, it is a great challenge to simultaneously achieve breathability, permeability, and comfortability for their development. Herein, mitigating the problem by miniaturizing and integrating the sensors is tried. Highly flexible and stretchable coaxial structure fiber‐shaped triboelectric nanogenerators (F‐TENGs) with a diameter of 0.63 mm are created by orderly depositing conductive material of silver nanowires/carbon nanotubes and encapsulated polydimethylsiloxane onto the stretchable spandex fiber. As a self‐powered multifunctional sensor, the resulting composite fiber can convert mechanical stimuli into electrical signals without affecting the normal human body. Moreover, the F‐TENGs can be easily integrated into traditional textiles to form tactile sensor arrays. Through the tactile sensor arrays, the real‐time tactile trajectory and pressure distribution can be precisely mapped. This work may provide a new method to fabricate fiber‐based pressure sensors with high sensitivity and stretchability, which have great application prospects in personal healthcare monitoring and human–machine interactions. [ABSTRACT FROM AUTHOR]

Herein, we describe a novel homogenous electrochemical aptasensor for the ultrasensitive detection of ractopamine (RAC) based on the signal amplification of a hairpin DNA cascade amplifier (HDCA) and electrocatalysis of dsDNA-templated copper nanoparticles. The present electrochemical aptasensor employs a label-free “turn-on” strategy with enzyme-free amplification. Briefly, the target RAC triggers the HDCA autocatalytic process of two ingeniously designed complementary hairpin DNA, which results in the formation of nucleic-acid-stabilized copper nanoparticles (dsDNA/CuNPs). Thus, with the mimic oxidase catalytic character of the dsDNA/CuNPs and enzyme-free hairpin DNA cascade amplifier reactions, a remarkable electrochemical response can be achieved, which is dependent on the concentration of the target RAC. Taking advantage of the highly amplified efficiency of trigger recycling and the excellent electrochemical catalytic response of dsDNA/CuNPs, the proposed strategy is capable of detecting RAC ultrasensitively. Under optimal conditions, the electrochemical signal increases with an increase in the target RAC concentration in the wide dynamic range from 1 × 10−12 M to 3 × 10−7 M with a detection limit (LOD) of 3 × 10−13 M. The proposed system does not need any sophisticated operation procedures such as electrode immobilization and expensive labeling. Therefore, the devised label-free and enzyme-free amplification homogeneous electrochemical aptasensor strategy may become an alternative method for the simple, sensitive, and selective detection of biological small molecules, proteins, nucleic acids and nuclease activity. [ABSTRACT FROM AUTHOR]