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To advance the industrialization of flexible strain sensors, an innovative flexible sensing fiber was developed through a sophisticated wet spinning process. Silver trifluoroacetate and graphene oxide (GO) were combined with thermoplastic polyurethane (TPU) to prepare the fibers via wet spinning. Ascorbic acid was used to in situ reduce the silver trifluoroacetate and graphene oxide within the polyurethane, causing the growth of silver nanoparticles to bond with reduced graphene oxide, forming a dual conductive pathway. This resulted in the creation of silver nanoparticles/reduced graphene oxide/polyurethane fibers (AgNPs-rGO-TPU sensing fibers). The tensile and sensing properties of AgNPs-rGO-TPU sensing fibers under different parameters were investigated. The results showed that with 25 wt% TPU as the matrix, 30 wt% silver trifluoroacetate, and 1 wt% graphene oxide, the fibers achieved an optimal balance of mechanical and sensing properties. The tensile strength was 7.69 MPa, the elongation at break was 370.75%, and the toughness modulus was 18.45 MJ m−3. The AgNPs-rGO-TPU sensing fibers effectively detect external stimuli, exhibiting high sensitivity over a wide strain range (gauge factor is 4.25 below 5% strain, 24.79 in the 5%–25% strain range, 23.06 in the 25%–80% strain range, and 21.32 in the 80%–110% strain range), with a conductivity of 163.17 ms·cm−1. They can stably recognize movements and physiological signals from various parts of the human body, showing good application prospects. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Shanghai Jiaotong University (Science) is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Modern intelligent electronic devices require electromagnetic interference (EMI) shielding composite films with outstanding shielding effectiveness and multifunctionality to adapt to increasingly complex application environments. In this work, inspired by the morphology of cocoa trees, SiO2 is conceived as the cocoa fruit and one-dimensional nanomaterial silver nanowires (AgNWs) as the branches. Utilizing the metal chelating properties of polydopamine (PDA), SiO2@PDA@AgNWs were formed and subsequently interwoven with cellulose nanofibers (CNFs) to create a nanocomposite film with a cocoa-tree-like structure, denoted as CNFs-AgNWs-SiO2@PDA (C-A-SP). Conductive AgNWs induce conductivity losses, while SiO2@PDA@AgNWs contribute to multiple scattering and interfacial polarization losses. Therefore, the C-A-SP nanocomposite film with a thickness of 59 μm demonstrates an impressive EMI shielding effectiveness (EMI SE) of 76.91 dB and exhibits a specific SE (SSE/t) of 15304.88 dB·cm2·g–1. Meanwhile, the thermal conductivities of in-plane and out-plane reached 4.15 and 0.15 W/(m·K), respectively. Additionally, the C-A-SP nanocomposite film also demonstrates an excellent strain-sensing capability. This study provides valuable insights for designing and fabricating lightweight, flexible, and multifunctional efficient EMI shielding composites. [ABSTRACT FROM AUTHOR]

Hyper-viscoelastic models have been used to characterize large strains coupled with viscosity. In this study, we aimed to model the urethral in-vivo biomechanics through a hyper-viscoelastic implementation. First, we used isotropic 2-parameter Demiray model for identification of urethral tube inflation after refining the values of quasistatic states. Attempting the approach by Holzapfel et. al., the average ratio of the elastic and dynamic modulus was computed to determine the stress contribution of the viscoelastic branches. The values of the parameters were determined after constraining a constant Energy dissipation (generalized maxwell) over range 1s to 100s. For the hyper-viscoelastic comparison implementation, it was observed that the goodness of fit criteria performs good for half of the samples (Adjusted R2>0.95). In some samples, the model is limited to fit ‘S’ shape curves but still performed well. The above identification technique and the hyper-viscoelastic in-silico approaches show that our approach fares sufficiently for the creep response characterization of the urethra.

This paper explores the development of 3D-printed self-sensing Ultra-High Performance Concrete (UHPC) by incorporating graphite (G) powder, milled carbon microfiber (MCMF), and chopped carbon microfiber (CCMF) as additives into the UHPC matrix to enhance piezoresistive properties while maintaining workability for 3D printing. Percolation curves were established to identify optimal filler inclusion levels, and a series of compressive tests, including quasi-static cyclic, dynamic cyclic, and monotonic compressive loading, were conducted to evaluate the piezoresistive and mechanical performance of 29 different mix designs. It was found that incorporating G powder improved the conductivity of the UHPC but decreased compressive strength for both mold-cast and 3D-printed specimens. However, incorporating either MCMF or CCMF into the UHPC resulted in the maximum 9.8% and 19.2% increase in compressive strength and Young's modulus, respectively, compared to the plain UHPC. The hybrid combination of MCMF and CCMF showed particularly effective in enhancing sensing performance, achieving strain linearity over 600 μ ε . The best-preforming specimens (3G250M250CCMF) were fabricated using 3 wt% of G, 0.25 wt% of MCMF, and 0.25 wt% of CCMF, yielding a maximum strain gauge factor of 540, a resolution of 68 μ ε , and an accuracy of 4.5 μ ε under axial compression. The 3D-printed version of the best-performing specimens exhibited slightly diminished piezoresistive and mechanical behaviors compared to their mold-cast counterparts, yielding a maximum strain gauge factor of 410, a resolution of 99 μ ε , and an accuracy of 8.6 μ ε . [ABSTRACT FROM AUTHOR]

The rapid advancement in attractive platforms such as biomedicine and human‐machine interaction has generated urgent demands for intelligent materials with high strength, flexibility, and self‐healing capabilities. However, existing self‐healing ability materials are challenged by a trade‐off between high strength, low elastic modulus, and healing ability due to the inherent low strength of noncovalent bonding. Here, drawing inspiration from human fibroblasts, a monomer trapping synthesis strategy is presented based on the dissociation and reconfiguration in amphiphilic ionic restrictors (7000‐times volume monomer trapping) to develop a eutectogel. Benefiting from the nanoconfinement and dynamic interfacial interactions, the molecular chain backbone of the formed confined domains is mechanically reinforced while preserving soft movement capabilities. The resulting eutectogels demonstrate superior mechanical properties (1799% and 2753% higher tensile strength and toughness than pure polymerized deep eutectic solvent), excellent self‐healing efficiency (>90%), low tangential modulus (0.367 MPa during the working stage), and the ability to sensitively monitor human activities. This strategy is poised to offer a new perspective for developing high strength, low modulus, and self‐healing wearable electronics tailored to human body motion. [ABSTRACT FROM AUTHOR]

[Display omitted] Electrically conductive fiberfibre/fabric composites (ECFCs) are competitive candidates for use in wearable electronics. Therefore, it is essential to develop mechanically robust ECFC strain sensors with sensing performance. In this study, MXene assembly and hot-pressing were combined to prepare strong yet breathable ECFCs for strain and temperature sensing. Hydrogen bonding between MXene and polyurethane (PU) and ultrasonication-induced interfacial sintering were responsible for MXene nanosheets assembly on the PU nanofibers. MXene decoration made PU nanofibers electrically conductive, resulting in a conductive network. Hot-pressing improved interface adhesion among the conductive nanofibers. Thus, the mechanical properties of the nanofiber composites, including tensile strength, toughness and fracture energy, were enhanced. The nanofiber composites exhibited surface stability and durability. When the nanofiber composites were used as strain sensors, they showed breathability with a linear resistance response ranging from 1 % to 100 % and cycling stability. In addition, they produced stable sensing signals over 1000 cycles when a notch was present. They could also monitor temperature variations with a negative temperature coefficient (−0.146 %/°C). This study provides an interfacial regulation method for the preparation of multi-functional nanofiber composites with potential applications in flexible and wearable electronics. [ABSTRACT FROM AUTHOR]

The increasing demand for flexible electromechanical devices with superior stretchability, durability, thermal stability and sensitivity has driven the development of new smart functional materials to replace conventional semiconductors. This study utilises combining electrospinning and in situ polymerisation to fabricate four types of thermoplastic polyurethane/polyaniline (TPU/PANI) nanofibrous membranes with varied fibre orientation and multiwalled carbon nanotubes (MWCNTs) incorporation. The combined effects of material composition and fibre alignment on strain‐sensing performance were systematically explored. All membranes exhibited stable, symmetric ohmic behaviour under strain, with current decreasing as strain increased. Remarkable repeatability and stability were observed in cyclic current–time tests. MWCNTs addition significantly enhanced conductivity, with aligned fibres further boosting performance. Gauge factor (GF) measurements revealed that aligned TPU/PANI mats had GFs of 7 (0%–18% strain) and 14.3 (18%–40%), while aligned TPU/MWCNTs/PANI mats had GFs of 5.2 (0%–13%) and 7.3 (13%–40%). Random TPU/PANI mats showed GFs of 13.9 (0%–11%) and 23.3 (11%–40%) and random TPU/MWCNTs/PANI mats had GFs of 13.9 (0%–19%) and 24.7 (19%–40%). Each configuration demonstrated suitability for specific applications, with random TPU/MWCNT/PANI mats exhibiting the best overall performance. This research provides critical insights into optimising flexible strain sensors by tuning both material composition and fibre orientation. [ABSTRACT FROM AUTHOR]

Liquid crystalline elastomers (LCEs) are a class of shape‐changing polymers with exceptional mechanical properties and potential as artificial muscles/polymer actuators. In this study, multifunctional LCE actuators with strain sensing and joule heating responsivity are developed. LCEs are successfully synthesized using the thiol‐ene two‐staged michael addition polymerization (TMAP) method. The LCE films are further functionalized via sequential polydopamine (PDA) and silver electroless coating. It is found that the PDA coating enabled the anchoring of the Ag particles to the LCE, thereby enabling the electrical conductivity of the Ag‐LCEs (<0.1 Ω cm−1). The studies confirm that the Ag/PDA coated LCEs can sense up to ≈30% strain, sense their own actuation strokes, and actuate at a rate of 1.83% s−1 while lifting a weight ≈50 times its mass in response to a 12 V 2A DC current. [ABSTRACT FROM AUTHOR]

Wearable technology refers to the devices that are integrated with textiles, or implanted in the body or plants for smart monitoring. Hence, this wearable technology has attracted tremendous attention from researchers globally due to its smart functions to be useful for mankind. The key target of this review is to examine the potential of rubber composite materials for such wearable devices. The rubber composites reviewed explore silicone rubber as a rubber matrix (SR). Another objective includes the use of multi‐walled carbon nanotubes (MWCNTs) in pristine and functionalization forms explored as reinforcing fillers. Moreover, prospects of CNT including their structure, properties, and types are explored both in pristine and functionalized state are reviewed. Following this, the mechanical, and electrical, properties of such composites are reviewed. The reported results show that the reinforcing properties are strongly improved by adding functional groups to CNT in rubber composite. These improvements in reinforcing properties are assisted by the functional groups like carboxyl (OH), carbonyl (CO), epoxy, and alkoxy (CO) on the surface of filler are useful. They assist in improving the filler‐rubber compatibility thereby improving filler dispersion and thus finally mechanical and electrical properties. Following this, such improved properties are explored for specific real‐time wearable technologies. This real‐time monitoring includes nursing plant pulse growth monitoring, health monitoring, and humidity sensors. The review further proposes that the functionalized CNTs can be useful for obtaining robust real‐time strain‐sensing monitoring. Moreover, it assists in obtaining sharp response time, strain sensitivity, and good stretchability. Finally, the prospects and challenges are explored discussing the real‐time monitoring of these sensors. Highlights: Configurations for nursing plant growth and other monitoring parameters are reviewed.The properties of pristine and functionalized carbon nanotubes reinforced silicone rubber for wearable technology were reviewed.The mechanical, and electrical aspects of functionalized carbon nanotubes were comparatively reviewed.Applications such as wearable strain sensors, humidity sensors, and wearable plant pulse monitoring sensors were reported. [ABSTRACT FROM AUTHOR]

Abstract Studies have increasingly aimed at improving the piezoresistive behavior of polymer‐based conductive composites (CPCs) for strain‐sensing, with inorganic nanomaterial enhancement offering research opportunities. This study investigates the impact of incorporating zinc sulfide nanospheres (ZnS NSs, 1–7 wt.%), synthesized via a one‐step hydrothermal method, into a poly(vinylidene fluoride) (PVDF) polymer matrix together with multi‐walled carbon nanotubes (MWCNTs). Field emission scanning electron microscopy (FE‐SEM), energy‐dispersive X‐ray spectroscopy (EDX), and X‐ray diffraction (XRD) analyses reveal that ZnS NSs comprise a mixture of ZnS0.96O0.04 and S phases. While of ZnS NSs minimally impact tensile properties of the PVDF/MWCNT composites, they reduce elongation at break at 5 wt.%. During 15‐cycle strain sensing up to 3% strain, ZnS NSs‐enhanced composites outperformed PVDF/1 wt.% MWCNT. The reference sample's resistance change ratio (ΔR/R0) decreased below 1% with increased cycles, while 1 wt.% ZnS NSs increased ΔR/R0 to 3%, reducing changes upon cycle increments. Higher ZnS NSs levels (3–7 wt.%) resulted in ΔR/R0 exceeding 4–5%, indicating enhanced strain sensing performance. Fourier‐transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM), differential scanning calorimetry (DSC), and thermogravimetric analysis (TGA) showed limited impact of ZnS NSs on the thermal properties and microstructure of the composites.

Abstract Strain sensors utilizing mechanoluminescent (ML) materials have garnered significant attention and application due to their advantages, such as self‐powering, non‐contact operation, and real‐time response. However, ML‐based strain sensing techniques typically rely on the establishing of a mathematical relationship between ML intensity and mechanical parameters. The absolute ML intensity is vulnerable to environmental factors, which can result in measurement errors. Herein, an color‐resolved visualized dynamic ML and self‐referencing strain sensing is investigated in Ca9Al(PO4)7: Tb3+, Mn2+. By analyzing the ML performance under various mechanical stimulations and adjustable strain parameters, a relationship between strain and the ML intensity ratio of Tb3+/Mn2+ is aimed to bed established. This will enable the development of a self‐referencing and visualized strain sensing technology. Through a comparison of luminescence characteristics under continuous mechanical stimulation (stretching) and continuous X‐ray irradiation, it is discovered that the ratiometric dynamic ML is primarily driven by the dynamic filling and continuous release of carriers form traps, which compensates for the ML of Mn2+. Leveraging the self‐referencing and color‐resolved (from green to red) visualized ML characteristics, an application scenario for monitoring human joint movement is developed. This approach offers new insights into the use of dynamic ML materials in strain sensing and human‐machine interaction.

For the need of direct contact with the skin, electronic skins (E‐skins) should not only fulfill electric functions, but also ensure comfort during wearing, including permeability, waterproofness, and easy removal. Herein, the study has developed a self‐adhesive, detach‐on‐demand, breathable, and waterproof E‐skin (PDSC) for motion sensing and wearable comfort by electrospinning styrene‐isoprene block copolymer rubber with carbon black nanosheets as the sensing layer and liner copolymers of N, N‐dimethylacrylamide, n‐octadecyl acrylate and lauryl methacrylate as the adhesive layer. The high elasticity and microfiber network structure endow the PDSC with good sensitivity and high linearity for strain sensing. The hydrophobic and crystallizable adhesive layer ensures robust, waterproof, and detaching‐on‐demand skin adhesion. Meanwhile, the fiber structure enables the PDSC good air and water permeability. The integration of electric and wearable functions endows the PDSC with great potential for motion sensing during human activities as both the sensing and wearable performances. [ABSTRACT FROM AUTHOR]

Developing multifunctional flexible composites with high-performance electromagnetic interference (EMI) shielding, thermal management, and sensing capacity is urgently required but challenging for next-generation smart electronic devices. Herein, novel nacre-like aramid nanofibers (ANFs)-based composite films with an anisotropic layered microstructure were prepared via vacuum-assisted filtration and hot-pressing. The formed 3D conductive skeleton enabled fast electron and phonon transport pathways in the composite films. As a result, the composite films showed a high electrical conductivity of 71.53 S/cm and an outstanding thermal conductivity of 6.4 W/m·K when the mass ratio of ANFs to MXene/AgNWs was 10:8. The excellent electrical properties and multi-layered structure endowed the composite films with superior EMI shielding performance and remarkable Joule heating performance, with a surface temperature of 78.3 °C at a voltage of 2.5 V. Additionally, it was found that the composite films also exhibited excellent mechanical properties and outstanding flame resistance. Moreover, the composite films could be further designed as strain sensors, which show great promise in monitoring real-time signals for human motion. These satisfactory results may open up a new opportunity for EMI shielding, thermal management, and sensing applications in wearable electronic devices. [ABSTRACT FROM AUTHOR]

The main failures that could deteriorate the reliable operation of solid rocket motors (SRMs) and lead to catastrophic events are related to bore cracks and delamination. Current SRMs' predictive assessment and damage identification practices include time-consuming and cost-demanding destructive inspection techniques. By considering state-of-the-art optical strain sensors based on fiber Bragg gratings, a theoretical study on the use of such sensors embedded in the circumference of the composite propellant grain for damage detection is presented. Deep neural networks were considered for the accurate prediction of the presence and extent of the defects, trained using synthetic datasets derived through finite element analysis method. The evaluation of this combined approach proved highly efficient in discriminating between the healthy and the damaged condition, with an accuracy higher than 98%, and in predicting the extent of the defect with an error of 2.3 mm for the bore crack depth and 1.6° for the delamination angle (for a typical ~406 mm diameter grain) in the worst case of coexistent defects. This work suggests the basis for complete diagnosis of solid rocket motors by overcoming certain integration and performance limitations of currently employed dual bond stress and temperature sensors via the more scalable, safe, sensitive, and robust solution of fiber optic strain sensors. [ABSTRACT FROM AUTHOR]

The development of easy and direct real-time monitoring of welded joint quality instead of surface damage analysis is crucial to improve the quality of industrial products. This work presents the results of high-density polyethylene (HDPE)-based composites with various carbon black (CB) content (from 20 to 30 vol.%) for use as a heating element and strain sensor in electrofusion-welded polymer joints. The pyroresistive heating process was used to determine the effect of generated Joule heat during welding on the structure and sensor properties of polymer–carbon composites. It is shown that the generation of Joule heat depends on the nanocarbon content and affects the crystallinity of the polymer matrix. The partial disruption of the conductive path of carbon black particles was observed and, as a result, a decrease in electrical conductivity for composites with lower CB content after welding was found. For the highest CB amount, conductivity increased, which is caused by smaller particle-to-particle distance for filler paths. Therefore, the best balance between pyroresistive and sensor properties was found. [ABSTRACT FROM AUTHOR]

The precise evaluation of micro-crack sizes and locations is crucial for the safe operation of structures. Traditional detection techniques, however, suffer from low spatial resolution, making it difficult to accurately locate micrometer-scale cracks. A method and experimental study were proposed in this paper for identifying and locating micro-cracks using optical fiber strain sensing based on OFDR to address this issue. The feasibility of this method for micro-crack detection was verified by the combination of a polyimide-coated sensing optical fiber (PISOF) and tight sheath sensing optical fiber (TSSOF). A calculation method for micro-crack widths based on distributed optical fiber strain curves was established, and the test results of different optical fibers were compared. Through multiple verification experiments, it was found that the strain peak curves of both fiber types could accurately locate micro-cracks with a precision of 1 mm. Additionally, the crack widths could be obtained by processing the distributed strain curves using a computational model, enabling the accurate capture of micro-crack characteristics at the 10 μm level. A strong linear relationship was observed between the optical fiber stretching length and the crack width. Notably, the relative error in calculating the crack width from the strain curve of PI fiber was very small, while a linear relationship existed between the maximum strain value of the TSSOF and the crack width, allowing for the calculation of the crack width based on the maximum strain value. This further validated the feasibility of the method designed in this paper for the analysis of micro-crack characteristic parameters. [ABSTRACT FROM AUTHOR]

Material cracking is one of the key mechanisms contributing to structural failure. Distributed fiber optic sensing (DFOS) can measure the strain profile along optical fiber distributively. However, the conventional strain measurement using a Brillouin-DFOS system (Brillouin optical time-domain analysis/reflectometry (BOTDA/R)) has a decimeter-order spatial resolution, making it difficult to measure the highly localized strain generated by a sub-millimeter crack. This paper introduces a crack analysis method based on decomposing the Brillouin scattering spectrum to overcome the spatial resolution induced crack measurement limitation of the BOTDA/R system. The method uses the non-negative least squares algorithm to back-calculate the strain profile within the spatial resolution around each measurement point. The performance of this method is verified by a four point bending test of a brittle slag cement-cement-bentonite beam. The crack width estimation error is improved to ±0.005 mm for a crack as narrow as 0.76 mm. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Railway Science & Engineering is the property of Journal of Railway Science & Engineering Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The accurate perception of external environment information through the robot foot is crucial for the mobile robot to evaluate its ability to traverse terrain. Adequate foot-end contact signals can provide robust support for robot motion control and decision-making processes. The shape and uncertain rotation of the wheel-legged robot foot end represent a significant challenge to sensing the robot foot-end contact state, which current foot-end sensing schemes cannot solve. This paper presents a sensing method for the tire stress field of wheel-legged robots. A finite element analysis was conducted to study the deformation characteristics of the foot-end tire under force. Based on this analysis, a heuristic contact position estimator was designed that utilizes symmetrical deformation characteristics. Strain sensors, arranged in an array, extract the deformation information on the inner surface of the tire at a frequency of 200 Hz. The contact position estimator reduces the dimensionality of the data and fits the eigenvalues to the estimated contact position. Using support vector regression, the force estimator utilizes the estimated contact position and sensor signal to estimate the normal reaction force, designated as FZ. The sensing system is capable of detecting the contact position on the wheel circumference (with a root mean square error of 1.150°), as well as the normal force of 160 N on the Z axis (with a root mean square error of 6.04%). To validate the efficacy of the sensor detection method, a series of randomized and repeated experiments were conducted on a self-constructed test platform. This novel approach offers a promising avenue for perceiving contact states in wheel-legged robots. [ABSTRACT FROM AUTHOR]

Copyright of Cotton Textile Technology is the property of Cotton Textile Technology Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Polymer Materials Science & Engineering is the property of Sichuan University, Polymer Research Institute and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The flexible silicone elastomer‐conductive composite was developed with enhanced energy harvesting and strain sensing. A hybrid nanofiller system with multi‐walled carbon nanotubes (MWCNTs) and titanium (IV) carbide (TiC) was used as reinforcing agents for the elastomer. The 4 MWCNT +5 TiC composite has 1.34 MPa tensile strength, 136.85% higher than unfilled silicone rubber (SR) matrix. The unfilled sample has a 1.558 MPa compressive modulus, while 4 MWCNT +5 TiC has 3.87 MPa. The machine and finger presses were utilized to test the energy harvesting of the composite. With greater cyclic stability, the 4 MWCNT +5 TiC sample performed exceptionally well in the machine press in the output voltage range of around 120 mV. Among the thumb presses, 2 MWCNT +5 TiC yielded the best results, with a voltage of about 100 mV. The 3 MWCNT +5 TiC sample produced 9044% more energy than the single filler 3 phr MWCNT sample from our previous work. Higher MWCNT content enhanced composite stiffness, making finger pressing harder and decreasing energy output. The strain sensing test on the 4 MWCNT +5 TiC composite showed high gauge factors (GF = 7.532 and 23.944) and good linearity (R2 = 0.909 and 0.939) over a strain range of Δε = 0%–14% and 14%–22%. Silicone composites' mechanical, energy harvesting, and strain sensing performance improved greatly with the MWCNT and TiC hybrid fillers. These composites could be used in self‐powered wearable electronics, machine or structural deformation monitoring, and human motion sensing. Highlights: A stretchable device was developed with improved energy harvesting and strain sensing.Rubber composites were fabricated from MWCNTs, TiC hybrid fillers, and SR matrix.The energy harvesting was 9044% higher for hybrid filler compared to MWCNT as the only filler.Robust strain sensing properties with a gauge factor of 23.9, linearity of 0.91, and relaxation time of 0.1 s.The final composites are useful for self‐powered wearable electronics, health monitoring, and human motion sensing. [ABSTRACT FROM AUTHOR]

The rise of the Internet of Things has spurred extensive research on integrating conductive materials into textiles to turn them into sensors, antennas, energy storage devices, and heaters. MXenes, owing to their high electrical conductivity and solution processability, offer an efficient way to add conductivity and electronic functions to textiles through simple dip coating. However, manual development of MXene‐coated textiles restricts their quality, quantity, and variety. Here, a versatile automated yarn dip coater tailored for producing continuously high‐quality MXene‐coated yarns and conducted the most comprehensive MXene‐yarn dip coating study to date is developed. Compared to manual methods, the automated coater provides lower resistance, superior uniformity, faster speed, and reduced MXene consumption. It also enables rapid coating parameter optimization, resulting in a thin Ti3C2 coating uniform over a 1 km length on a braided Kevlar yarn while preserving its excellent mechanical properties (over 800 MPa) and adding Joule heating and damage sensing to composites reinforced by the yarns. By dip‐coating five different yarns of varying materials, diameters, structures, and chemistries, new insights into MXene‐yarn interactions are gained. Thus, the automated dip coating presents ample opportunities for scalable integration of MXenes into a wide range of yarns for diverse functions and applications. [ABSTRACT FROM AUTHOR]

Abstract Human–machine interactive platforms that can sense mechanical stimuli visually and digitally are highly desirable. However, most existing interactive devices cannot satisfy the demands of tactile feedback and extended integration. Inspired by the mechanoluminescence (ML) function of cephalopod skin and the sensitive perception of microcracked slit‐organs, a bioinspired stretchable interactive platform is developed by designing a stretchable poly(styrene‐block‐butadiene‐block‐styrene)/fluorescent molecule (SFM) composite followed by the in situ polymerization of pyrrole (Py) and deposition of carbon nanotubes (CNTs), which possesses a simple multilayered structure and quantitatively senses the applied strains via the variations of digital electrical resistance and visual fluorescence intensity. Using the strain‐dependent microstructures derived from the synergistic interactions of the rigid PPy/CNTs functional layer and SFM, the SFM/PPy/CNTs‐based platforms exhibit excellent strain‐sensing performance manifested by a high gauge factor (GF = 2.64 × 104), wide sensing range (~270%), fast response/recovery time (~155/195 ms), excellent stability (~15,000 cycles at 40% strain), and sensitive ML characteristics under ultraviolet illumination. Benefiting from the novel fusion of digital data and visual images, important applications, including the detection of wrist pulses and human motions, and information dual‐encryption, are demonstrated. This study demonstrates the superiority of advanced structures and materials for realizing superior applications in wearable electronics.

We investigate a simple structure in which a polarization-maintaining fiber (PMF) is sandwiched between two single-mode fibers (SMFs). By injecting broadband light and observing the modal interference spectrum of the transmitted light in the 870 nm range, we identify a clear shift dependent on the strain applied to the PMF. In addition, we demonstrate that in the same wavelength range, the strain applied to the SMFs before and after the PMF does not influence the interference spectrum. This result confirms that only the PMF segment exhibits strain sensitivity. [ABSTRACT FROM AUTHOR]

AbstractStructural health monitoring (SHM) of brittle structures will require versatile sensing instrumentation that can transmitting transient loadings into rapid electrical responses. This research investigated the sensing performance of CNT Buckypaper (CNT-BP) thin-films on stressed fiber-reinforced composites, which are integral materials to various industries of the infrastructure. Three-point bending experiments revealed an extraordinary gauge factor (∼40) and impressive response linearity. Electrical responses were instantaneous; moreover, low force impacts were detectable, the sensors provided clear indications of spatial recognition. Most importantly, the manufacturing methods are scalable and cost effective compared to commercialized strain gauges. This study examined micro-strain measurements (

Abstract This study investigates the development of thermoplastic polyurethane (TPU) filaments incorporating multi‐walled carbon nanotubes (MWCNT) to enhance strain‐sensing capabilities. Various MWCNT reinforcement ratios are used to produce customized feedstock for fused filament fabrication (FFF) 3D printing. Mechanical properties and the piezoresistive response of samples printed with these multifunctional filaments are concurrently evaluated. Surface morphology and microstructural observations reveal that higher MWCNT weight percentages increase filament surface roughness and rigidity. The microstructural modifications directly influence the tensile strength and strain energy of the printed samples. The study identifies an apparent percolation threshold within the 10–12 wt.% MWCNT range, indicating the formation of a conductive network. At this threshold, higher gauge factors are achieved at lower strains. A newly introduced Electro‐Mechanical Sensitivity Ratio (ESR) parameter enables the classification of composite behaviors into two distinct zones, offering the ability to tailor self‐sensing structures with on‐demand properties. Finally, flexible structures with proven application in soft robotics and shape morphing are fabricated and tested at different loading conditions to demonstrate the potential applicability of the custom filaments produced. The results highlight a pronounced piezoresistive response and superior load‐bearing performance in the examined structures.