Search Results (618)

Thermo-physiological comfort of automotive seating is governed by the complex interaction between seat-cover materials, their structural configuration, and the heat and moisture exchange occurring at the seat–body interface during prolonged sitting. While numerous studies have examined individual textile constructions or isolated comfort parameters, integrated evaluations combining objective material testing with dynamic microclimate measurements under realistic loading conditions remain limited. This study thoroughly examined six commercially important vehicle seat-cover materials that represent laminated, warp-knitted, and woven polyester architectures. Standardized laboratory techniques were used to quantify objective comfort qualities, such as air permeability, water vapor permeability, thermal resistance (Rct), and evaporative resistance (Ret) and transient heat flux test (H-test). Simultaneously, a multi-sensor system was used to constantly monitor temperature and relative humidity at the seat–body interface during sitting loading in a controlled subjective microclimate experiment at room temperature. The findings show that lamination technique and textile structure have a major impact on both transient microclimate behavior and steady-state material properties. Increased air and moisture transmission in warp-knitted and more open structures resulted in reduced evaporative resistance and more stable microclimate conditions. Denser laminated structures, on the other hand, exhibited more resistance to heat and evaporation, which led to a greater buildup of moisture when they were seated. Different temporal responses in temperature and humidity were also shown by the multi-sensor microclimate studies, underscoring the significance of assessing comfort beyond static material metrics. This study demonstrates that static thermos-physiological parameters alone are not sufficient to predict real stated comfort behavior. By integrating time-resolved microclimate analysis under realistic seated loading with standardized testing, a more reliable evaluation framework for automotive seat-cover comfort is proposed. Full article

With the advent of ubiquitous healthcare and advancements in textile industry, non-invasive wearable biomedical solutions are becoming an increasingly attractive alternative to in-hospital monitoring, allowing for timely diagnostics and prediction of severe medical conditions. Non-contact biopotential monitoring is particularly promising because non-contact biopotential electrodes can be applied over clothing or embedded in the material without almost any preparation. However, due to the intricacies of capacitive coupling they rely on, the design of such electrodes and their interface with the body plays a key role in achieving measurement repeatability and their widespread utilization in clinical-grade diagnostics. Based on exhaustive investigation of several decades of the literature on non-contact and capacitive biopotential electrodes and electric potential sensors, this study is intended to serve as a state-of-the-art overview of their historical development and design challenges, a collecting point for important research theories and development milestones, a starting point for anyone seeking for a soft head start into this research area, and a remedy for occasional misnomers and conceptual errors identified in the existing papers. The ultimate goal of this comprehensive analysis is to demystify phenomena of non-contact biopotential monitoring and capacitive coupling, systematically reconciliate terminological inconsistencies, and enhance accessibility to the most important findings for future research. To accomplish this, fundamental concepts are thoroughly revisited—from fundamentals of electrochemistry and working principles of capacitors and operational amplifiers to system stability and frequency-domain analysis. With the use of various mathematical tools (Laplace transform, phasors and Fourier analysis, and time-domain differential calculus), discussions on non-contact and capacitive biopotential electrodes, collected from the 1960s onward, are for the first time compiled into a unified, abstracted, bottom-up analysis. The laid-out inspection provides analytical explanation for various aspects of measurement results available in the referenced literature, but also serves an educative purpose by devising a methodological framework that can be easily applied to other similar research fields. Firstly, the differences and similarities between wet, dry, surface-contact, non-contact, capacitive, insulated, on-body, and off-body biopotential electrodes are clarified. For this purpose, equivalent electrical models of various non-invasive biopotential electrodes are analyzed and compared. As a result, a proposal for a revised classification of biopotential electrodes is given. Secondly, instead of using the concept of a purely capacitive biopotential electrode, a test is proposed for assessing the predominant coupling mechanism achieved with an electrode over an insulating layer. Thirdly, a fundamental model of a buffer active non-contact biopotential electrode and its interface with the body is built and generalized, and the proposed test is applied for analyzing the influence of voltage attenuation and phase shifts on signal morphology. Lastly, guidelines for designing the described electrode–body interfaces are proposed, along with a discussion on practical aspects of their implementation. Full article

The rapid growth of electronic devices, including wearable sensors, has increased electronic waste, driving interest in sustainable, biocompatible materials. Electrospun biomaterials have emerged as versatile substrates for multifunctional wearable textiles, offering flexibility, high surface area, tunable porosity, and biocompatibility. Using natural polymers (e.g., silk fibroin, cellulose, chitosan) and synthetic polymers (e.g., polycaprolactone, polylactic acid, PVDF), electrospinning produces nanofibrous mats capable of supporting thermal regulation, moisture management, and integrated sensing for pressure, temperature, humidity, or chemical detection. Nature-inspired designs, hybrid composites, and advanced architectures enable passive and active thermoregulation via phase-change materials, thermochromic dyes, hydrogels, and conductive nanofibers, while maintaining wearer comfort, breathability, and skin safety. Despite progress, challenges persist in durability, washability, energy efficiency, manufacturing scalability, and recyclability. This review provides a comprehensive overview of biomaterials, fabrication techniques, multifunctional sensor integration, and thermoregulation strategies, highlighting opportunities for next-generation wearable textiles that combine sustainability, adaptive thermal management, and high-performance sensing. Full article

Continuous blood pressure (BP) monitoring remains a major challenge in wearable healthcare systems, as conventional cuff-based sphygmomanometers are intermittent and unsuitable for long-term use. This study presents a Smart Sock platform for cuffless BP estimation using single-site photoplethysmography (PPG). Unlike approaches based on pulse transit time or fiducial point detection, the proposed framework relies on peak-independent features extracted from PPG and its first and second derivatives, capturing blood volume and hemodynamic dynamics in the lower limb. PPG signals from 60 participants were segmented into overlapping 30 s windows and processed through a unified preprocessing pipeline. A compact set of physiologically meaningful statistical and information-theoretic features was extracted from each window, and temporal lag modelling (5–15 s) was employed to encode short-term hemodynamic memory without explicit peak detection. Multiple regression models were assessed using leakage-safe cross-validation strategies. In a subject-independent diagnosis scenario, the system achieved errors of 8.60 mmHg for systolic BP and 6.42 mmHg for diastolic BP. In a monitoring scenario with single-point calibration, performance substantially improved, yielding mean absolute errors of 1.3–1.7 mmHg and R² > 0.90. These results demonstrate that foot-based PPG, combined with peak-independent feature engineering and temporal context modeling, enables accurate and comfortable continuous personalized blood pressure monitoring after calibration, while subject-independent estimation remains more challenging. Full article

Fire hazards in closed industrial environments pose a significant threat to workers, infrastructure and production processes. Traditional detection systems, such as smoke and heat detectors, often have limitations in their settings, including delayed response time and a tendency for false alarms due to non-fire factors such as dust, humidity and vapors. This paper researches the applicability of gas sensors as an alternative or complementary method for early fire detection. This research presents an experimental evaluation of six gas sensors integrated with a microcontroller. Tests were conducted in a controlled environment, simulating industrial conditions by monitoring the combustion of different materials, such as wood, plastic and textile. Sensor responses were analyzed at horizontal distances of 2 m and 4 m from the fire source. Results show that all sensors detected combustion byproducts, with those at 2 m exhibiting a faster response and higher concentration readings. The findings confirm that a multi-sensor approach significantly increases detection reliability and enables an earlier response compared to conventional systems. Full article

With the rapid development of artificial intelligence and wearable electronics, there is an increasing demand for skin-like, flexible, and self-powered sensors capable of continuously perceiving mechanical stimuli and human motions. Triboelectric nanogenerator (TENG)-based sensors incorporating stretchable conductive gels represent a promising approach to meet these requirements by combining soft mechanical compliance with efficient electromechanical signal transduction. However, conventional metallic or composite electrodes often suffer from mechanical mismatch with soft skin-like systems, motivating the exploration of intrinsically soft and stretchable conductive gels. In this review, we present a comprehensive and structured overview with comparative perspectives of stretchable skin-like conductive gel-based triboelectric devices. First, different classes of conductive gels, including hydrogels, organogels, ionogels, and other emerging gel systems, are systematically summarized and compared in terms of their composition, crosslinking strategies, conductivity, and mechanical characteristics. Next, the pivotal role of conductive gels in bridging skin-like sensing functions and triboelectric applications is elucidated, highlighting how their intrinsic softness, stretchability, self-healing capability, and interfacial conformability enable intimate skin contact and reliable electromechanical coupling. The key performance attributes of gel-based skin-like triboelectric sensors, including stretchability, self-healing behavior, optical and thermal tolerance, electrical durability, and environmental stability, are critically discussed with representative examples and comparative analysis. Typical device configurations, such as thin-film, fiber-shaped, and textile-based architectures, are further reviewed to illustrate structure–function relationships and application-oriented design strategies. Finally, current challenges, limitations, and future research directions for stretchable conductive gel-based triboelectric systems are outlined, aiming to provide practical guidelines and insights for the rational design of high-performance skin-like triboelectric sensors based on conductive gels. Full article

The objective of this research is to enable the engineered manufacturing of sewn and embroidered e-textiles. It is achieved by conducting sewability assessments of commercially available conductive yarns and providing optimal sewing parameters to ensure electrical performance and mechanical suitability. Our approach includes yarn sampling, measurements, sewing experiments, statistical modeling, and performance tests of sewn sensors. We have scrutinized a range of conductive yarns with different formation mechanisms and electrical conductivities. Highly conductive, flexible, and fine count yarns are of particular interest in this proposed research. The physical properties of selected conductive yarns have been characterized and sewing experiments have been followed to evaluate the machine sewability of these conductive yarns under diverse sewing conditions. Using multiple logistic regressions and machine learning, these empirical observations are generalized and sewability models are established. Full article

Wearable sensing technologies are increasingly used to assess neuromuscular function during daily-life activities. This study presents and evaluates a multisensor wearable system integrating a textile-based surface Electromyography (sEMG) sleeve and a pressure-sensing insole for monitoring Tibialis Anterior (TA) and Gastrocnemius Lateralis (GL) activation during gait. Eleven healthy adults performed overground walking trials while synchronised sEMG and plantar pressure signals were collected and processed using a dedicated algorithm for detecting activation intervals across gait cycles. All participants completed the walking protocol without discomfort, and the system provided stable recordings suitable for further analysis. The detected activation patterns showed one to four bursts per gait cycle, with consistent TA activity in terminal swing and GL activity in mid- to terminal stance. Additional short bursts were observed in early stance, pre-swing, and mid-stance depending on the pattern. The area under the sEMG envelope and the temporal features of each burst exhibited both inter- and intra-subject variability, consistent with known physiological modulation of gait-related muscle activity. The results demonstrate the feasibility of the proposed multisensor system for characterising muscle activation during walking. Its comfort, signal quality, and ease of integration encourage further applications in clinical gait assessment and remote monitoring. Future work will focus on system optimisation, simplified donning procedures, and validation in larger cohorts and populations with gait impairments. Full article

Transcranial Magnetic Stimulation (TMS) is a non-invasive technique for neurological research and therapy, but its effectiveness depends on accurate and stable coil placement. Manual localization based on anatomical landmarks is time-consuming and operator-dependent, while state-of-the-art robotic and neuronavigation systems achieve high accuracy using optical tracking with head-mounted markers and infrared cameras, at the cost of increased system complexity and setup burden. This study presents a cost-effective, markerless robotic-assisted TMS system that combines a 3D depth camera and textile capacitive sensors to assist coil localization and contact control. Facial landmarks detected by the depth camera are used to estimate the motor cortex (C3) location without external tracking markers, while a dual textile-sensor suspension provides compliant “soft-landing” behavior, contact confirmation, and coil-tilt estimation. Experimental evaluation with five participants showed reliable C3 targeting with valid motor evoked potentials (MEPs) obtained in most trials after initial calibration, and tilt-verification experiments revealed that peak MEP amplitudes occurred near balanced sensor readings in 12 of 15 trials (80%). The system employs a collaborative robot designed in accordance with international human–robot interaction safety standards, including force-limited actuation and monitored stopping. These results suggest that the proposed approach can improve the accessibility, safety, and consistency of TMS procedures while avoiding the complexity of conventional optical tracking systems. Full article

Far-infrared (FIR)-emitting textiles are increasingly used in sleepwear; however, their influence on sleep physiology has not been comprehensively evaluated with multi-modal wearable sensing. This randomized, double-blind, placebo-controlled crossover study examined whether FIR-emitting garments modulate nocturnal thermoregulation, autonomic activity, and sleep architecture. Fifteen healthy young men completed two overnight laboratory sleep sessions wearing either FIR-emitting garments or visually matched polyester controls. Tympanic membrane temperature (TMT), sweating rate, skin temperature, and humidity were continuously monitored using wearable sensors, and sleep stages and heart rate variability (HRV) were assessed using validated portable systems. Compared with control garments, FIR garments produced consistently lower TMT across the night (p = 0.004) and reduced mid-sleep sweating (condition × time interaction: p = 0.026). The proportion of rapid eye movement (REM) sleep was higher in the FIR condition (22.2% ± 6.5% vs. 18.6% ± 6.5%, p = 0.027), despite no changes in total sleep time or sleep efficiency. A transient increase in low-frequency power during early sleep (p = 0.027) suggested baroreflex-related thermal adjustments without sympathetic activation. These findings indicate that FIR-emitting garments facilitate mild nocturnal heat dissipation and support REM expression, demonstrating their potential as a passive intervention to improve sleep-related thermal environments. Full article

The study proposes a sensor-based experimental protocol for quantifying dynamic facial temperature changes during face mask use by means of infrared thermography (IRT). Eight face masks, including filtering respirators, surgical masks, and one textile mask, were evaluated on three participants under controlled indoor conditions. Thermographic data were acquired at four defined measurement stages: prior to mask application, immediately after donning, after 15 min of continuous wear, and immediately after removal. The measurements reveal a reproducible temporal temperature pattern across participants and mask types, consisting of an initial cooling phase, subsequent heat accumulation during wear, and a pronounced temperature increase following removal. Thermal variations were observed both in mask-covered and uncovered facial regions. The inner canthus exhibited high sensitivity to these changes, supporting its use as a stable reference area. The study demonstrates the suitability of IRT for protocol-driven, non-contact assessment of dynamic facial thermal response during mask use. Full article

Wearable antennas for wireless sensor network (WSN) applications require circularly polarized (CP) radiation to maintain stable communication link under human body movement and complex environments. However, many existing wearable CP antennas rely on either linearly polarized (LP) or CP radiator with a single axial ratio (AR) mode combined with external polarization conversion structures, which limit the achievable axial ratio bandwidth (ARBW). In this work, an all-textile wideband CP antenna with a square-ring notched slot radiator, a 50 Ω microstrip line, and a 3 × 3 nonuniform metasurface (MTS) is proposed for 5.85 GHz WSN applications. Unlike conventional CP generation approaches, the square-ring notched slot, analyzed using characteristic mode analysis (CMA), directly excites three distinct AR modes, enabling potential wideband CP radiation. The nonuniform MTS further improves IBW performance by exciting additional surface wave resonances. Moreover, the nonuniform MTS further enhances ARBW by redirecting the incident wave into an orthogonal direction with equivalent amplitude and a 90° phase difference at higher frequency region. The proposed antenna is composed of conductive textile and felt substrates, offering flexibility for wearable applications. The proposed antenna is measured in free space, on human bodies, and fresh pork in an anechoic chamber. The measured results show a broad IBW and ARBW of 84.52% and 43.56%, respectively. The measured gain and radiation efficiency are 4.47 dBic and 68%, respectively. The simulated specific absorption rates (SARs) satisfy both US and EU standards. Full article

Compression garments are widely employed in medical and sports contexts for their ability to promote venous return, manage oedema, support musculoskeletal function, and enhance athletic recovery. Advances in textile-based compression systems have been driven by innovations in fibres, yarn structures, fabric structure engineering, and design methods. This review critically examines the current literature on compression garments, highlighting the influence of raw materials and yarn architectures on performance, durability, and wearer comfort. Attention is given specially to fabric structures and manufacturing methods, where the evolution from traditional cut-and-sew methods to advanced seamless, flatbed, and circular knitting technologies is highlighted, along with their impact on pressure distribution and overall garment efficacy. The integration of 3D body scanning, finite element analysis, and predictive modelling, which enables more personalised and precise garment design, is also speculated upon. Moreover, the review highlights testing and evaluation methodologies, spanning both in vivo and in vitro based assessments, pressure sensor studies for real-time monitoring, and theoretical models mostly based on Laplace’s law. This literature survey provides a foundation for future innovations aimed at optimising compression garment design for both therapeutic and athletic use. Full article

Developments in the textile industry occur both as a consequence of increased awareness among users and various requirements in terms of human and environmental safety. Modifications are aimed at improving performance parameters, using natural substances, moving away from synthetic materials, and improving ergonomics. In order to achieve this, various fibre-production techniques are used, as is the addition of substances, including nanosubstances, into the structure or onto the surface of a given material. In the case of fire-resistant fabrics, which primarily must meet thermal protection requirements, efforts are also being made to reduce weight and eliminate harmful chemicals (e.g., polycyclic aromatic hydrocarbons PAHs), and to create smart materials with sensors. However, it is necessary to further develop not only the materials themselves but also cleaning and decontamination techniques that will allow the fire resistance parameters that have been developed to be maintained. Full article

Flexible strain sensors capable of conformal integration with living organisms are essential for advanced wearable electronics, human–machine interaction, and plant health. However, many existing sensors require complex fabrication or rely on non-breathable elastomer substrates that interfere with the physiological microenvironment of skin or plant tissues. Here, we present a low-cost, breathable, and highly stretchable strain sensor constructed from biomedical materials, in which a double-layer medical elastic bandage serves as the porous substrate and an intermediate conductive medical elastic tape impregnated with carbon nanotubes (CNTs) ink acts as the sensing layer. Owing to the hierarchical textile porosity and the deformable CNTs percolation network, the sensor achieves a wide strain range of 100%, a gauge factor of up to 2.72, and excellent nonlinear second-order fitting (R² = 0.997). The bandage substrate provides superior air permeability, allowing long-term attachment without obstructing moisture and gas exchange, which is particularly important for maintaining skin comfort and preventing disturbances to plant epidermal physiology. Demonstrations in human joint-motion monitoring and real-time plant growth detection highlight the device’s versatility and biological compatibility. This work offers a simple, low-cost yet effective alternative to sophisticated strain sensors designed for human monitoring and plant growth monitoring, providing a scalable route toward multifunctional wearable sensing platforms. Full article