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Highlights The high‐performance flexible pressure sensors demonstrate significant potential in wearable electronics, robotics, human‐machine interfaces, and healthcare. However, the preparation of bionic flexible sensors with high sensitivity and low detection limit is still a big challenge. This study proposes a bionic flexible sensor based on the hierarchical microstructure of eggshells, which improves sensing performance and reduces detection limits by constructing a bionic body with good microstructure. The developed sensor incorporates hierarchical microstructures and interlocked architectures, which complement each other to improve the sensor's sensing performance. The enhancement effect of microstructure on sensor sensitivity was studied by comparative experiments. Experimental results show that the eggshell‐inspired bionic flexible sensor in this study has a high sensitivity of 15.01 kPa−1 and a low detection limit (~4 Pa). In addition, the bionic sensor has a rapid response time (~180 ms) and excellent durability (~1000 cycles), making it a reliable platform for human body detection, dynamic load, and sound monitoring. This study provides great potential for innovative applications of bionic flexible sensors in electronic skin and sound monitoring. Hierarchical and interlocked microstructure enables the low detection limit. A wide range of applications in weak physiological signals. Effectively detect and distinguish different sounds. A sustainable strategy to convert wasted resources into functional materials. [ABSTRACT FROM AUTHOR]

Monitoring the cardiovascular health of patients and early diagnosis of heart diseases are highly sought after as they can represent a true cornerstone in tomorrow's healthcare surveillance. Here, an unprecedented non‐invasive device prototype is reported for pulse wave velocity (PWV) measurement based on a piezoelectric graphene pressure sensor. PWV is a critical health indicator that estimates arterial stiffness by measuring the velocity of arterial pulse flow through the circulatory system. The sensor incorporates advanced electronic components and data analysis tools, enabling the measurement of pulse transit time (PTT), that is the time required for the pulse wave to travel between carotid and femoral artery sites. Significantly, the outcomes obtained through the novel method, which involved monitoring 10 patients within clinical environment, show statistical similarity to results obtained using established technology for the PWV estimation such as SphygmoCor. In particular, the mean difference between measurements done with the two techniques resulted in 0.1 m s−1, that is <2%, underscoring the reliability of the novel device. The technology holds big promise for enhancing cardiovascular healthcare delivery: it is wearable, potentially exploitable by a non‐expert user, and it needs to be powered with just 0.2 V, thus it can become compatible even with applications in point‐of‐care settings. [ABSTRACT FROM AUTHOR]

Reduced graphene oxide (rGO) thin films have demonstrated various advantages in flexible electronics. So far, solution processes are widely used for making rGO thin films for their mild operation conditions and low cost. However, wrinkles are frequently formed due to the capillary contraction during drying, which severely deteriorates the conductivity and the transparency of rGO thin films. Here, an ultra‐smooth rGO nano‐thin film, featuring wrinkle‐free and a rather low surface roughness of 1.38 nm is developed, which is attributable to a steady and homogeneous thin liquid film confined by a conical fiber array. The thin liquid film facilitates both in‐plane stacking of nanosheets and reducing the buried solvent under nanosheets. Notably, with the capillary flow replenishing the tri‐phase contact line evaporation, a semi‐dry film near the tri‐phase contact line is produced, that enables the force equilibrium of multi‐directional capillary forces on dispersed nanosheets for depositing a wrinkle‐free nanofilm. The as‐prepared rGO nanofilm gives a low sheet resistance of 8.3 kΩ sq−1 and a high transmittance of 91.9%, showing better performances than other reported rGO nanofilms. On this basis, it is demonstrated that a high‐sensitive pressure sensor with a detection limit as low as 0.02 Pa, highlighting the solution‐processed innovative ultra‐smooth 2D nanomaterial thin films, and devices. [ABSTRACT FROM AUTHOR]

So far, there have been no high-quality studies examining the efficacy of outpatient biofeedback devices in cases of prescribed partial weight-bearing, such as after surgery on the lower limbs. This study aimed to assess whether a biofeedback device is more effective than using a personal scale. Two groups of healthy individuals wearing an insole orthosis were trained to achieve partial loading in a three-point gait within a target zone of 15–30 kg during overground walking and going up and down stairs. The treatment group (20 women and 22 men) received continuous biofeedback, while the control group (26 women and 16 men) received no information. Findings were compared in a randomized controlled trial. Compliance with partial loading without biofeedback was poor; on level ground and stairs, only one in two steps fell within the target area, and overloading occurred on at least one in three steps. The treatment group reduced the percentage of steps taken in the overload zone to ≤8.4% (p < 0.001 across all three courses) and achieved more than two-thirds of their steps within the target zone (p < 0.001 on level ground, p = 0.008 upstairs, and p = 0.028 downstairs). In contrast, the control group did not demonstrate any significant differences in the target zone (p = 0.571 on level ground, p = 0.332 upstairs, and p = 0.392 downstairs). In terms of maintaining partial load, outpatient biofeedback systems outperform bathroom scales. [ABSTRACT FROM AUTHOR]

The conventional medical assistive strategy for wearable devices involves sensing physiological signals and subsequent analysis while it lacks the capability for visual interaction and often necessitates the use of additional bulky devices for display. Herein, a perceptual and interaction strategy based on electroluminescent and triboelectric sensing 3D stacked wearable device (ETD) is proposed to address current issues. The ETD utilizes a bottom triboelectric sensor for tactile physiological information, which is processed and analyzed, ultimately triggering the selective illumination of the top electroluminescent array through external power circuitry. The ETD possesses the capability to generate a 100 V with 1.5 cm2 and stable visual interaction ability at 30 V drive voltage. Based on outstanding features of the ETD, two medical assistance scenarios are explored. I) The ETD captures physiological signals, such as pulse rate, respiratory rate, and special joint flexion, and in situ displays the corresponding physiological information, effectively assisting the patients/elders in self‐monitoring. II) A bidirectional interactive telemedicine assistive system utilizing ETDs is implemented, which not only gathers real‐time activity status from patients/elders but also realizes that remote physician assesses the safety status and the assessment results are wirelessly back‐communicated to the ETD, enabling real‐time interaction of the physician advice. [ABSTRACT FROM AUTHOR]

The design and development of Indium Tin Oxide (ITO) thin film based piezoresistive pressure sensor is presented in this paper. ITO (90:10) nanoparticles were synthesized by green combustion method using indium and tin as precursors and, carica papaya seed extract as fuel. ITO (90:10) thin film piezoresistors were deposited using synthesized nanoparticles on AlN coated circular steel (SS 304) diaphragm using E-beam evaporation technique. Diaphragm models of different thickness (0.75, 1 and 1.25 mm) were created using ANSYS finite element analysis in order to determine the maximum stress and deflection region for applied pressure of 1 to 10 bar. ANSYS results exhibited that maximum stress and deflection occurred at the center and circumference of diaphragm. ITO thin film piezoresistors were deposited at these regions using mechanical mask. TiW metal contact was established to these ITO thin film piezoresistors using DC sputtering method. ITO thin film piezoresistive pressure sensor with TiW contact connected in Wheatstone full bridge configuration was calibrated and tested for 50 pressure cycles by applying 2 V DC supply. Sensitivity (S) of the developed ITO thin film pressure sensor was obtained as 0.686, 0.566 and 0.495 mV/bar for diaphragm thickness of 0.75, 1, and 1.25 mm pressure sensors respectively. The non-linearity (NLi) in the output response of the pressure sensors was found to be 9.14, 9.82 and 11.27% for diaphragm thickness of 0.75, 1, and 1.25 mm respectively. Hysteresis errors were found to be 0.0344, 0.0525 and 0.054 for diaphragm thickness of 0.75, 1, and 1.25 mm respectively. [ABSTRACT FROM AUTHOR]

Tactile sensing in the human body is achieved via the skin. This has inspired the fabrication of synthetic skins with pressure sensors for potential applications in robotics, bio‐medicine, and human–machine interfaces. Tactile sensors based on magnetic elements are promising as they provide high sensitivity and a wide dynamic range. However, current magnetic tactile sensors mostly detect pressures of solid objects and operate at relatively high forces about 100 mN. Herein, these limitations are addressed by manufacturing soft, stretchable, and hair‐like structures that are permanently magnetized to achieve high‐resolution, cost‐effective, and high‐resolution pressure sensing. Combining these hair‐like structures with advances in 3D magnetic‐field measurements allows us to monitor directional tactile pressures without solid contact. To prove the concept of this technology, a bio‐inspired soft device is built with a hairy structure that senses and reports environmental mechanical stresses, similar to that of human skin. Simple self‐assembly of the soft magnetic hair structure makes our approach easy to scale for large‐area applications. [ABSTRACT FROM AUTHOR]

Currently, multifunctional MXene‐integrated wearable textiles (MWTs) are particularly appealing due to their various applications such as health monitoring, smart protection, and medical treatment. However, scalable manufacture of durable, stable, and high‐performance multifunctional MWTs still face challenges due to the poor oxidation stability of MXene and low utilization of precursor titanium aluminum carbide (MAX). Herein, an improved preparation strategy for zinc ion (Zn2+) intercalation is proposed to create high antioxidative MXene (ZM) and exceptionally conductive and printable gel ink based on MXene sediments (ZMS‐ink), while multifunctional wearable textiles are fabricated using spray‐coating and screen‐printing techniques on cellulosic nonwoven textiles (CNWs), achieving the complete utilization of MXene precursor. Benefiting from the inherent disordered stacking and porous structure of CNWs, along with the highly conductive ZM and ZMS‐ink, as‐prepared smart, wearable and green‐based pressure sensor offered proper breathability, high sensitivity (2602.26 kPa−1), wide sensing range (0–141 kPa), and excellent cycling stability (>5000 cycles). Additionally, the sensor exhibited efficient photothermal/photodynamic therapy antibacterial activity and exceptional electromagnetic interference shielding performance (57.5 dB). Therefore, this work paves the way for the future development of integrated and scalable multifunctional wearable devices building on the environmental‐friendly CNWs incorporated with fully utilized MAX, offering a green and cost‐effective approach. [ABSTRACT FROM AUTHOR]

This study delves into the development of a novel 10 by 10 sensor array featuring 100 pressure sensor pixels, achieving remarkable sensitivity up to 888.79 kPa−1, through the innovative design of sensor structure. The critical challenge of strain sensitivity inherent is addressed in stretchable piezoresistive pressure sensors, a domain that has seen significant interest due to their potential for practical applications. This approach involves synthesizing and electrospinning polybutadiene‐urethane (PBU), a reversible cross‐linking polymer, subsequently coated with MXene nanosheets to create a conductive fabric. This fabrication technique strategically enhances sensor sensitivity by minimizing initial current values and incorporating semi‐cylindrical electrodes with Ag nanowires (AgNWs) selectively coated for optimal conductivity. The application of a pre‐strain method to electrode construction ensures strain immunity, preserving the sensor's electrical properties under expansion. The sensor array demonstrated remarkable sensitivity by consistently detecting even subtle airflow from an air gun in a wind sensing test, while a novel deep learning methodology significantly enhanced the long‐term sensing accuracy of polymer‐based stretchable mechanical sensors, marking a major advancement in sensor technology. This research presents a significant step forward in enhancing the reliability and performance of stretchable piezoresistive pressure sensors, offering a comprehensive solution to their current limitations. [ABSTRACT FROM AUTHOR]

With the development of science and technology, wearable electronics are increasingly widely used in medical, environmental monitoring, and other fields. Thus, the demand for flexible electrodes is increasing. The two-dimensional material Ti3C2Tx has attracted much attention in the manufacture of flexible electrodes due to its excellent mechanical and electrical properties. However, the brittleness of pure Ti3C2Tx films has become a major obstacle for their use as flexible electrodes in wearable devices. Therefore, solving the brittleness problem of flexible electrodes based on Ti3C2Tx while maintaining the excellent performance of Ti3C2Tx has become an urgent problem. To solve this problem, Ti3C2Tx was compounded with waterborne polyurethane (WPU), and a Ti3C2Tx-WPU composite film with a hierarchical structure was constructed by evaporation-assisted self-assembly. The Ti3C2Tx-WPU composite film not only retains the excellent electrical conductivity of Ti3C2Tx (100 S m−1) but also has flexibility (20 MJ m−3). Furthermore, the Ti3C2Tx-WPU composite film is applied to functional devices such as contact pressure sensors and non-contact proximity sensors. Finally, the Ti3C2Tx-WPU composite film wearable device demonstrates its practical application potential in the field of wearable devices. [ABSTRACT FROM AUTHOR]

An automated device is designed to measure the density of a liquid material using hydrostatic pressure method. A low cost pressure sensor is calibrated and used to get highly accurate readings. The calibration is done by measuring the pressure values vs. the generated voltage signal. The calibration has been challenging due to the low accuracy of the sensor but proved to be highly effective in applications. The interface is developed using a microcontroller, motor drives, analog to digital converters and sensors. The device is designed to get several readings automatically by changing the positions of the device/liquid column heights to increase the accuracy. Also the device can be programmed to measure the real time density of a liquid continuously. The readings were analyzed and averaged by a software developed in python language. The instruments accuracy was tested against 3 liquid types, water, coconut oil, kerosene oil, and showed a low error (0.007%, 0.001%, and 0.002% respectively) compared to the readings of a standard Pycnometer. The low error percentages confirm the accuracy of the device and the effectiveness of the sensor calibrations. [ABSTRACT FROM AUTHOR]

Colonoscopy has a limited field of view because it relies solely on a small camera attached to the end of the scope and a screen displayed on a monitor. Consequently, the quality and safety of diagnosis and treatment depend on the experience and skills of the gastroenterologist. When a novice attempts to insert the colonoscope during the procedure, excessive pressure can sometimes be applied to the colon wall. This pressure can cause a medical accident known as colonic perforation, which the physician should prevent. We propose an assisting device that senses the pressure applied to the colon wall, analyzes the risk of perforation, and warns the physician in real time. Flexible pressure sensors are attached to the surface of the colonoscope shaft. These sensors measure pressure signals during a colonoscopy procedure. A simple signal processor is used to collect and process the pressure signals. In the experiment, a colonoscope equipped with the proposed device was inserted into a simulated colon made from a colon extracted from a pig. The processed data were visually communicated to the gastroenterologist via displays and light-emitting diodes (LEDs). The device helps the physician continuously monitor and prevent excessive pressure on the colon wall. In this experiment, the device appropriately generated and delivered warnings to help the physicians prevent colonic perforation. In the future, the device is to be improved, and more experiments will be performed in live swine models or humans to confirm its efficacy and safety. [ABSTRACT FROM AUTHOR]

The high cost and limited availability of home spirometers pose a significant barrier to effective respiratory disease management and monitoring. To address this challenge, this paper introduces a novel Venturi-based spirometer designed for home use, leveraging the Bernoulli principle. The device features a 3D-printed Venturi tube that narrows to create a pressure differential, which is measured by a differential pressure sensor and converted into airflow rate. The airflow is then integrated over time to calculate parameters such as the Forced Vital Capacity (FVC) and Forced Expiratory Volume in one second (FEV1). The system also includes a bacterial filter for hygienic use and a circuit board for data acquisition and streaming. Evaluation with eight healthy individuals demonstrated excellent test-retest reliability, with intraclass correlation coefficients (ICCs) of 0.955 for FVC and 0.853 for FEV1. Furthermore, when compared to standard Pulmonary Function Test (PFT) equipment, the spirometer exhibited strong correlation, with Pearson correlation coefficients of 0.992 for FVC and 0.968 for FEV1, and high reliability, with ICCs of 0.987 for FVC and 0.907 for FEV1. These findings suggest that the Venturi-based spirometer could significantly enhance access to spirometry at home. However, further large-scale validation and reliability studies are necessary to confirm its efficacy and reliability for widespread use. [ABSTRACT FROM AUTHOR]

The evolution of clothing towards functionalization and intelligence has led to increasing attention on wearable smart garments. In modern military combat systems, the smart sensing fabric plays crucial role in soldiers' combat attire. It possesses characteristics of perception, feedback, response, as well as the softness and wearability of textiles. This enables it to detect changes in the external environment and make corresponding adjustments to meet specific needs. In the military field, smart sensing fabrics can more comfortably and safely monitor soldiers health status while playing an important role in battlefield information perception, combat command, and other aspects. It can monitor soldiers' physiological states, environmental changes, and battlefield situations in a real-time manner, providing commanders with timely and accurate information support to enhance soldiers survivability and combat effectiveness. The smart sensing fabric integrates various types of sensors with fabric substrates to perceive and monitor various physical or environmental parameters, converting them into readable electrical signals. Featureing excellent flexibility, stretchability, and wearability, it is able to conform to various human body curves and irregular shapes, meeting the demands of different application scenarios, especially suitable for scenarios requiring flexible measurement of strain or pressure. This article systematically reviews the research progress in recent years on textile-based strain sensors, pressure sensors, temperature sensors and humidity sensors, and the application of smart sensing textiles in military equipment. It also analyzes issues such as data security, washability, stability, and reliability of data transmission. Therefore, the smart sensing fabric demonstrates tremendous development potential and diverse applications in the military equipment field, such as monitoring soldiers' physiological states, battlefield environments, and movement postures. As textile technology advances and intelligent technologies continue to evolve, smart sensing fabrics will achieve more innovations in materials, functions, and structures. They will not only become lighter, softer, and more comfortable but also integrate more sensors and intelligent components for more precise and comprehensive perception and monitoring. [ABSTRACT FROM AUTHOR]

A pressure of approximately 15–25 mmHg is used for effective compression therapy to prevent and treat hypertrophic scar formation in patients with burns. However, conventional facial compression garments present challenges owing to inadequate pressure distribution in curved areas such as the cheeks, around the mouth, and the slope of the nose. This study aimed to evaluate the utility of a custom-made 3D compression mask equipped with pressure sensors to treat facial burn scars. This single-blinded, prospective randomized controlled trial was conducted between May and October 2023, involving 48 burn scars in 12 inpatients with facial burns. We created the custom-made 3D compression mask equipped with pressure sensors, inner lined with biocompatible silicon, and a harness system using 3D printing technology, which can continuously monitor whether an appropriate pressure of 15–25 mmHg maintains. The biological scar properties, Vancouver Scar Scale (VSS), and Patient and Observer Scar Assessment Scale (POSAS) scores in patients with facial burns were assessed before applying the compression mask and garment and at 4 and 12 weeks after application. Pre-application assessment of biological scar properties, VSS, and POSAS revealed no statistically significant differences between the 3D mask and control groups (p > 0.05 for all). Throughout the 12-week application, skin hydration and scar thickness significantly increased (p < 0.001) and reduced (p = 0.010), respectively , in the 3D mask group compared to the control group. Additionally, significant improvements in scar pliability (p = 0.004) and height (p = 0.009) of VSS, itching (p = 0.047), scar stiffness (p = 0.001), thickness (p = 0.011), and irregularity (p < 0.001) of POSAS-patient component, and scar thickness (p = 0.001), pliability (p = 0.012), and surface area (p = 0.027) of the POSAS-observer component were observed in 3D mask group throughout the 12-week application compared to the control group. The customized 3D compression mask equipped with pressure sensors significantly improved scar thickness, skin hydration, and various assessment scale parameters throughout the 12-week application. • Customized 3D compression mask maintains a pressure of approximately 15–25 mmHg. • Real-time pressure feedback aids scar management. • More improved facial scar thickness and skin hydration in the 3D mask group. • 3D compression masks were more effective than conventional compression garment. [ABSTRACT FROM AUTHOR]

[Display omitted] Flexible pressure sensors with high sensitivity and wide sensing range are highly desired in e-skins and wearable electronics. However, there is always a trade-off between high sensitivity and broad sensing range for most flexible pressure sensors. Herein, an artificial wheat awn-like hierarchical structure is designed onto the dielectric layer of the iontronic pressure sensor, realizing both high sensitivity and broad working range. The sensor is constructed by sandwiching a wheat awn-like polyvinyl alcohol/H 3 PO 4 dielectric layer between two transparent electrodes of silver nanowires/thermoplastic polyurethane/ionic liquid. The obtained sensor exhibits a high precision of 1 Pa, a high sensitivity of 47.65 kPa−1 (1–200 Pa), a wide measurement range from 1 Pa to 238 kPa, short response/recovery time of 13 ms/12 ms, outstanding stability over 6000 cycles, as well as good transparency. Considering these excellent properties, the sensor shows promising potential in health monitoring, human–computer interaction, wearable electronics, etc. [ABSTRACT FROM AUTHOR]

Piezoresistive pressure sensors, analyzing and converting external pressure signals to readable electrical signals for monitoring human health, are always subjected to simultaneously possess high signal‐linearity and signal sensitivity. Analogous to the control of sophisticated microstructure for increasing active sensing area, the control of gradient conductivity should enable a linear response via regulating the formed saturation current. Here, inspired by phase separation showing the feasibility of controlling material microstructure and conductivity, a high‐performance flexible pressure sensor via the simultaneous control of microgroove structure and wide‐range gradient conductivity is demonstrated. First, a laser‐etching and dopamine (DA)‐doping synergistic approach is used to induce selective phase separation in poly(3,4‐ethylenedioxythiophene): poly(styrenesulfonic acid) (PEDOT:PSS), achieving broad conductivity modulation (from 297 to 4525 S cm−1) and precise microgroove pattern (15.5 µm). Then, by designing conductivity‐gradient PEDOT: PSS‐based multi‐sublayers and microgroove interlocked structure, the sensor shows extraordinarily comprehensive performance of excellent stress‐sensing sensitivity (4 × 105 kPa−1), high linear responsiveness (99.85%) and wide‐range sensing ability (up to 100 kPa). Consequently, this sensor reveals excellent capability in detecting multi‐mode pressure changes and is expected to branch out into other electronic device designs as a general strategy for the precise manipulation of material physical‐chemical properties. [ABSTRACT FROM AUTHOR]

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Fecal incontinence (FI) referred to the inability to control the leakage of solid, liquid, or gaseous feces, the artificial anal sphincter (AAS) was the last resort for patients with FI except enterostomy. In order to the clinical application value of AAS was improved, the detection and analysis of intestinal pressure information was very necessary. Biaxial actuated artificial anal sphincter (BAAS) was a new type of AAS, which not only had a stable, long-term and safe energy supply, but also could provide real-time feedback of intestinal pressure information. In this paper, the BAAS was implanted into piglets for a long-term animal experiment. Piglets’ life habits, defecation habits and intestinal pressure were analyzed. The analysis results showed that the BAAS system had good feces control effect, when the actuator of the BAAS system was closed, there was basically no fecal leakage of piglets, and when the actuator of the BAAS system was opened, the piglets could defecate normally. Under the normal condition of the piglets’ health state and the BAAS’s operating state, the accuracy of the defecation perception reached to 65.79%. This study realized the in-depth study of the mechanism of piglets’ defecation, and provided guidance for the development of a new generation of AAS. [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.)

Heart failure imposes a significant global health burden, standing as a primary contributor to mortality. Various indicators and physiological shifts within the body may hint at distinct cardiac conditions. Specific biosensors have the capability to identify these changes. Integrating or embedding these biosensors into mechanical circulatory support devices (MCSDs), such as left ventricular assist devices (LVADs), becomes crucial for monitoring alterations in biochemical and physiological factors subsequent to an MCSD implantation. Detecting abnormal changes early in the course of disease progression will allow for improved patient outcomes and prognosis following an MCSD implantation. The aim of this review is to explore the available biosensors that may be coupled or implanted alongside LVADs to monitor biomarkers and changes in physiological parameters. Different fabrication materials for the biosensors are discussed, including their advantages and disadvantages. This review also examines the feasibility of integrating feedback control mechanisms into LVAD systems using data from the biosensors. Challenges facing this emerging technology and future directions for research and development are outlined as well. The overarching goal is to provide an overview of how implanted biosensors may improve the performance and outcomes of LVADs through continuous monitoring and closed-loop control. [ABSTRACT FROM AUTHOR]

High‐performance flexible pressure sensors have garnered widespread applications across numerous vital fields, encompassing flexible robotics, artificial intelligence, and brain‐computer interfaces. However, the small compressibility range of flexible materials and the easy saturation characteristics of microstructures greatly limit their practical applications. Therefore, achieving high sensitivity over an extensive pressure range remains a challenge. Here, inspired by the skin, a raised structure with graded features is designed as the sensitive layer. A flexible pressure sensor with high performance is manufactured by combining iontronic interfaces. The results indicate that this sensor can stably maintain a high sensitivity of 161.26 kPa−1 even at a pressure of 320 kPa. Moreover, this sensor also has a fast response time and recovery time of 26 and 85 ms, respectively. As a demonstration, these sensors are applied to materials stiffness recognition, human motion monitoring, and control of long‐distance four‐wheel vehicles. This work will offer valuable insights and serve as a useful reference for achieving high sensitivity and a broadened sensing range in sensors. [ABSTRACT FROM AUTHOR]

Due to its excellent performance, reduced graphene oxide aerogel (rGA) has been widely used in recent years. Typically, the mechanical and electrical properties of graphene oxide can be enhanced through doping, compositing, or heat treatment. This work presents a simple, fast, and environmentally friendly method for producing high-performance rGA using two reducing agents. During the reduction process, ascorbic acid can cross-link and reduce graphene oxide, while the reducing ability of ammonium citrate restores the conjugated structure of the graphene sheets. By fixing the concentration of ascorbic acid and adjusting the amount of ammonium citrate, we can obtain DrGA-2 that possesses both mechanical and electrical properties. The maximum strain and stress of DrGA-2 are 40.0% and 21.5 kPa, respectively. Meanwhile, only a 10% compressive strain is sufficient to induce a 95% resistance change rate. When DrGA-2 is assembled into a capacitive sensor, its capacitance change rate ranges from 80% to 200% under different strain conditions, enabling real-time monitoring of subtle human movements. This demonstrates the tremendous potential of this material in this field. [ABSTRACT FROM AUTHOR]

The present work demonstrates the manufacturing process of a pneumatic bellow actuator with an embedded sensor, utilizing a novel manufacturing approach through the complete use of additive manufacturing techniques, such as direct ink writing (DIW) and traditional fused deposition modeling (FDM) methods. This study is innovative in its integration of a dielectric electroactive polymer (DEAP) structure with sensing electrodes made of conductive carbon grease (CCG), showcasing a unique application of a 3D-printed DEAP with CCG electrodes for combined DEAP sensing and pneumatic actuation. Initial experiments, supported by computational simulations, evaluated the distinct functionality of the DEAP sensor by itself under various pressure conditions. The findings revealed a significant change in capacitance with applied pressure, validating the sensor's performance. After sensor validation, an additive manufacturing process for embedding the DEAP structure into a soft pneumatic actuator was created, exhibiting the system's capability for dual sensing and actuation, as the embedded sensor effectively responded to applied actuation pressure. This dual functionality represents an advancement in soft actuators, especially in applications that require integrated and responsive actuation and sensing capabilities. This work also represents a preliminary step in the development of a 3D-printed dual-modality actuator (pneumatic and electrically activated DEAP) with embedded sensing. [ABSTRACT FROM AUTHOR]

The field of compact optical microcavities has received significant research in the past decades, and a broad range of cavity‐based micromechanical sensors has been demonstrated. The present approach replaces the frequently employed, complex etched cantilever and membrane structures with a simple thin‐film system based on a compressible photonic microcavity to achieve pressure‐sensitive wavelength shifting of resonant modes. The effects of a topological dielectric mirror architecture on the light propagation in the system are extensively investigated. Topologically improved light‐matter interaction is experimentally demonstrated for systems where thin‐film devices are mounted on one side of the photonic cavity due to mechanical constraints. Coupled topological states are examined under the aspect of mode splitting and exhibit advantageous splitting tunability compared to non‐topological systems. The findings are complemented by the proposal of a simple spectral evaluation method allowing significant improvement in the precision of integrated Fabry‐Pérot sensors. The readout concept of the presented sensor allows a scalable improvement of the measurement precision by evaluating the resonant‐mode order in the deformable cavity. The experimental results and conceptual advancements provide pathways for significant improvements addressing the efficiency of light‐matter interaction in Fabry‐Pérot cavities and the readout precision of sensors incorporating thin‐film photodiodes in multimode photonic cavities. [ABSTRACT FROM AUTHOR]

Flexible pressure sensors with high sensitivity over a broad sensing range are of great value in daily life and highly desired in various extreme environment, from human motion inspection to heavy industrial robots to high energy radiation and extremely cold/high temperature environments. However, it remains a significant challenge for a single pressure sensor to simultaneously possess high sensitivity and broad detection range due to the trade‐off between these two properties. Here, a high‐performance pressure sensor is developed based on flexible modified silicon rubber/functionalized carbon nanotube (MSR/FCNT). The designed nested‐cell architecture and molecular surface modification strategy endow the pressure sensor with high sensitivity (>28 kPa−1) over 10 MPa sensing range, an ultralow detection limit (≈0.94 Pa), an ultrahigh pressure resolution (0.0075%) at a pressure of 3 MPa, and a low fatigue over 10 000 repetitive cycles even at an extremely high pressure of 5 MPa. Furthermore, the resulting sensor presents excellent durability after freezing at extreme cold temperature (−80 °C) as well as resistance to high temperature (200 °C) and high‐energy X‐ray radiation. The proposed nested‐cell architecture is a generic strategy for porous materials to achieve broad range high sensitivity. [ABSTRACT FROM AUTHOR]

Schematic illustration of plantar pressure distribution visualization system including a 9-channel pressure sensor array, analog to digital converter, data analysis software, and operation interface. [Display omitted] Based on real-time detection of plantar pressure, gait recognition could provide important health information for rehabilitation administration, fatigue prevention, and sports training assessment. So far, such researches are extremely limited due to lacking of reliable, stable and comfortable plantar pressure sensors. Herein, a strategy for preparing high compression strength and resilience conductive iongels has been proposed by implanting physically entangled polymer chains with covalently cross-linked networks. The resulting iongels have excellent mechanical properties including nice compliance (young's modulus < 300 kPa), high compression strength (>10 MPa at a strain of 90 %), and good resilience (self-recovery within seconds). And capacitive pressure sensor composed by them possesses excellent sensitivity, good linear response even under very small stress (∼kPa), and long-term durability (cycles > 100,000) under high-stress conditions (133 kPa). Then, capacitive pressure sensor arrays have been prepared for high-precision detection of plantar pressure spatial distribution, which also exhibit excellent sensing performances and long-term stability. Further, an extremely sensitive and fast response plantar pressure monitoring system has been designed for monitoring plantar pressure of foot at different postures including upright, forward and backward. The system achieves real-time tracking and monitoring of changes of plantar pressure during different static and dynamic posture processes. And the characteristics of plantar pressure information can be digitally and photography displayed. Finally, we propose an intelligent framework for real-time detection of plantar pressure by combining electronic insoles with data analysis system, which presents excellent applications in sport trainings and safety precautions. [ABSTRACT FROM AUTHOR]

The sustainable tactile electronics demonstrates huge potential in mimicking the functionality of human skin and satisfies with an eco‐friendly concept. However, on the premise of successfully introducing natural materials, such electronics are still not sufficient for improving the fatigue threshold in high‐frequency sensing scenarios. Here an eco‐ and user‐friendly cellulose integrated tactile array (CITA) is introduced that relies on laminated hierarchical architecture (LAHA) for alleviating the notorious structural vulnerability toward long‐term haptic evaluation. By cross‐validation with conventional bulky configuration, finite element simulation unveils that the LAHA leverages compact laminated adjacent layer for dramatically facilitating in‐plane stress distribution for diminishing the interfacial stress concentration, thus affords prolonged and reliable sensory augmentation. The CITA wireless monitoring system offers impeccable real‐time spatiotemporal haptic patterns on multi‐user interfaces and can substantially promote a record‐high durability (150000 cycles), showcasing low interfacial contact impedance (1.78 ± 0.4 ohm, 1 kHz), remarkably channel uniformity (97.2%), unparalleled sensitivity (12944 kPa−1), and sensing‐robustness against perturbations (e.g., humidity, temperature, and bending). It is envisioned that the proposed CITA system will open up new avenues for sustainable tactile electronics in continuous health surveillance. [ABSTRACT FROM AUTHOR]

Abstract—The paper explores the origins of offset voltage in piezoresistive pressure sensors, focusing on the impact of external factors such as temperature and internal factors like doping on sensor behavior. The study constructs a behavioral macro-model of a piezoresistive pressure sensor using the PSPICE simulator, leveraging primitives from the SPICE library. The investigation particularly addresses the offset voltage, a common issue in pressure measurements that can introduce inaccuracies. By understanding and mitigating these factors, the study aims to enhance the precision and reliability of piezoresistive pressure sensors for various applications. [ABSTRACT FROM AUTHOR]

Pressure sensors prepared from sapphire exhibit excellent characteristics, including high-temperature resistance, high hardness, and resistance to electromagnetic interference. A Fast Fourier Transform and Mean Square Error (FFT-MSE) demodulation algorithm was employed to demodulate a sapphire sandwich-structure Fabry–Perot (F-P) pressure sensor. Through simulation analysis, the experimental results indicated that the demodulation error of the air cavity length in the range of 206 μm to 216 μm was less than 0.0008%. Compared to single demodulation methods and combined demodulation methods based on FFT or Minimum Mean Square Error (MMSE), the method proposed in this work reduced the demodulation error by more than three times and increased accuracy by more than six times. The algorithm was utilized to demodulate the sapphire sandwich-structure F-P pressure sensor, and the test results indicated that the fitting error of the sensor was less than 0.025% within the pressure range of 0 MPa to 10 MPa. The repeatability error was less than 0.066%, the zero-point deviation was 1.26%, and the maximum stability deviation was 0.0063% per 30 min. The algorithm effectively demodulated the actual cavity length variation in the sapphire sandwich-structure F-P pressure sensor, providing a solution for the performance evaluation of the sapphire sandwich-structure F-P pressure sensor. [ABSTRACT FROM AUTHOR]

The purpose of the research discussed in this article is to explore the possibility of creating hybrid soft ballistic panel (BP) package variants by integrating into their composition layers of graphene-modified para-aramid fabrics in combinations with the different ballistic Kevlar textiles to improve the durability of the first layers of the soft ballistic panel. To address this goal, the liquid-phase exfoliation (LPE) method was used for integrating dispersions into composites to solve a number of topical problems in the stages of the technological sequence development of processing methods and optimizing processing parameters in accordance with the processing specifics of aramid textiles to achieve the desired properties of modified ballistic fabric, including the provision of coating adhesion to the surface to be modified. To test the results, ballistic experiments were performed and the back-face signature (BFS) of bullet impact on a backing material was analysed according to standards. Bullet impacts on the first ballistic protective fabric layers were also studied. [ABSTRACT FROM AUTHOR]

Flexible silicone materials have excellent elastic properties and can maintain excellent structural stability under high-intensity repeated deformation. They are ideal materials for preparing piezoresistive flexible sensors. However, traditional silicone materials exhibit strong insulation properties. The solid block structure is also not conducive to improving sensitivity. Inspired by the irregular hole structure of Taihu Lake stone, this paper prepared a porous silica gel skeleton (rGO/CTAB/SG) based on reduced graphene oxide film coating, which was equipped with flexible interdigital electrodes to achieve electrical signal derivation. The "honeycomb" shaped sensing module prepared in this way achieves an extremely wide elastic deformation range (20-200%). In the pressure feedback layer, the rGO film is evenly coated on the SG surface, which greatly improves the device conductivity and sensing performance (high sensitivities of 89.4 kPa− 1 and 25.4 kPa− 1 are achieved within 0-30.2 kPa and 30.2–42 kPa, ultra-high durability under more than 22,000 load-unload cycles.) Numerical simulation analysis results confirmed that the structure of the flexible substrate SG prepared by this method maintained well when extreme deformation occurred, and no fracture or stress concentration occurred. As an elastic sensor, after being integrated with a microprocessor, it can easily monitor and analyze human body movement in real time. It has huge potential in areas such as daily training and health monitoring of athletes. [ABSTRACT FROM AUTHOR]

We propose a photonic crystal-based cascaded micro ring resonator to increase the quality factor using the concept of two-dimensional constrained topological edge states. The topological features of the photonic crystal are used to acquire the increased quality factor by finite-difference time-domain (FDTD) numerical simulation. Two micro ring resonators with different band topologies that come together at an interface and are confined inside a slab of dielectric material give rise to a topological edge state. The transmission dropout issue arises whenever the quality factor is enhanced in a conventional photonic system, which can be improved remarkably by employing the present approach. As an application, the proposed topological edge state structure is used to increase the sensitivity and quality factor of the pressure sensor. In FDTD simulation, resonance wavelength shifts are employed to calculate the pressure of a system, while structural deformation and refractive index change are used as input parameters. The proposed structure is incredibly small and suitable for photonic integrated circuits. [ABSTRACT FROM AUTHOR]

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Since the beginning of the twentieth century, oxygen has been an essential therapeutic drug. Patients with chronic lung disease and other conditions rely on supplemental oxygen provided by oxygen cylinders for treatment. Because of the sudden increase in oxygen demand caused by the COVID-19 pandemic, combined with a lack of oxygen supply, new methods of oxygen delivery have been investigated as a potential solution. We propose OxySaver, a novel low-cost (∼60$) demand oxygen delivery system that may significantly reduce oxygen consumption. The proposed system consists of a pressure sensor that detects the patient's demand for oxygen, a normally open solenoid valve that switches the supply ON/OFF on demand, and a processing unit that ensures the supply of oxygen only during the patients' inhalation. It is simple to install using existing oxygen cylinders and oxygen pipelines in hospitals. The preliminary prototype tests have been promising, with OxySaver able to save up to 67% more oxygen than conventional methods. OxySaver's pulse setting can reach 18 LPM, as opposed to the 0.2–4 LPM typically found in oxygen concentrators. The system only needs 3.72 W at 50 bpm, which is less than other similar devices. OxySaver in multiplexing mode has the potential to reduce the logistical challenges associated with oxygen refilling and transport. The device is now ready for clinical testing at the bedside. [ABSTRACT FROM AUTHOR]

Electronic devices have become ubiquitous in our daily lives, leading to a surge in the use of microwave absorbers and wearable sensor devices across various sectors. A prime example of this trend is the aramid nanofibers/polypyrrole/nickel (APN) aerogels, which serve dual roles as both microwave absorbers and pressure sensors. In this work, we focused on the preparation of aramid nanofibers/polypyrrole (AP15) aerogels, where the mass ratio of aramid nanofibers to pyrrole was 1:5. We employed the oxidative polymerization method for the preparation process. Following this, nickel was thermally evaporated onto the surface of the AP15 aerogels, resulting in the creation of an ultralight (9.35 mg·cm−3). This aerogel exhibited a porous structure. The introduction of nickel into the aerogel aimed to enhance magnetic loss and adjust impedance matching, thereby improving electromagnetic wave absorption performance. The minimum reflection loss value achieved was −48.7 dB, and the maximum effective absorption bandwidth spanned 8.42 GHz with a thickness of 2.9 mm. These impressive metrics can be attributed to the three-dimensional network porous structure of the aerogel and perfect impedance matching. Moreover, the use of aramid nanofibers and a three-dimensional hole structure endowed the APN aerogels with good insulation, flame-retardant properties, and compression resilience. Even under a compression strain of 50%, the aerogel maintained its resilience over 500 cycles. The incorporation of polypyrrole and nickel particles further enhanced the conductivity of the aerogel. Consequently, the final APN aerogel sensor demonstrated high sensitivity (10.78 kPa−1) and thermal stability. In conclusion, the APN aerogels hold significant promise as ultra-broadband microwave absorbers and pressure sensors. [ABSTRACT FROM AUTHOR]

Conductive hydrogels are becoming one of the most important milestones for the development of new scaffolds, biosensors, supercapacitors, and green electronics within the field of biomedicine. In this work, we study the effect of different types of electroactive additives such as poly(3,4-ethylenedioxythiophene), tannic acid, and carbon quantum dots (CQDs), to form different poly(vinyl alcohol) (PVA)-based hydrogels with enhanced electrochemical properties. Different physicochemical tests are carried out to characterize the different PVA-based hybrid hydrogels and the rates of their degradation and loss of electroactivity throughout an eight-week biodegradation process. This work shows the individual and synergistic effects of the additives on various mechanical properties, including storage modulus and swelling ratio, and electrochemical properties of the PVA hydrogel. The additives have proven to enhance the electroactivity of the PVA-based hydrogels but as well their degradation. Finally, the use of the new hydrogel as a pressure sensor is also investigated. The study provides an insight on the potential use of CQDs, in synergy with other electroactivity enhancers, in the fabrication of novel hybrid conducting hydrogels in green electronics. [ABSTRACT FROM AUTHOR]

Artificial skin involves multidisciplinary efforts, including materials science, biology, medicine, and tissue engineering. Recent studies have aimed at creating skins that are multifunctional, intelligent, and capable of regenerating tissue. In this work, we present a specialized 3D printing ink composed of polyurethane and bioactive glass (PU-BG) and prepare dual-function skin patch by microfluidic-regulated 3D bioprinting (MRBP) technique. The MRBP endows the skin patch with a highly controlled microstructure and superior strength. Besides, an asymmetric tri-layer is further constructed, which promotes cell attachment and growth through a dual transport mechanism based on hydrogen bonds and gradient structure from hydrophilic to superhydrophilic. More importantly, by combining the features of biomedical skin with electronic skin (e-skin), we achieved a biomedical and electronic dual-function skin patch. In vivo experiments have shown that this skin patch can enhance hemostasis, resist bacterial growth, stimulate the regeneration of blood vessels, and accelerate the healing process. Meanwhile, it also mimics the sensory functions of natural skin to realize signal detection, where the sensitivity reached up to 5.87 kPa−1, as well as cyclic stability (over 500 cycles), a wide detection range of 0–150 kPa, high pressure resolution of 0.1 % under the pressure of 100 kPa. This work offers a versatile and effective method for creating dual-function skin patches and provide new insights into wound healing and tissue repair, which have significant implications for clinical applications.

A hydraulic support height measueement sensor based on Pascal's law is designed to address the difficulties in measuring the height, reliability, and stability of hydraulic supports in fully mechanized working faces. The height measurement sensor is equipped with a slender liquid tube, which is filled with methyl silicone oil. Pressure sensors are installed at both ends of the height measuremenr sensor. By measuring the pressure at both ends of the sealed liquid tube, the height difference between the two ends of the height measuremenr sensor is obtained. Methyl silicone oil has obvious thermal expansion and contraction characteristics when the ambient temperature changes, which can cause a sharp change in pressure in a closed space and affect measurement precision. A compensation method is proposed. The method stores a portion of methyl silicone oil in a corrugated tube, and uses the elasticity of the corrugated tube itself to compensate for the volume change caused by thermal expansion and contraction of methyl silicone oil. The method calibrates the density change caused by the volume change of methyl silicone oil through algorithms in the software to ensure the measurement precision of the height measurement sensor. The test results show that the height measuremenr sensor can operate in an environment of 0-40 ℃, with a measurement error of less than 4 cm. The on-site application results of the hydraulic support in the fully mechanized working face of thin and medium thick coal seams show that compared with manual measurement results, the error of the height measurement sensor is within 5 cm, indicating high reliability of the sensor.

Abstract Acoustic waves generated by seismic waves contain information on the internal structure of planets, and can be sensed by pressure sensors onboard high-altitude balloons. To identify the various contributions (infrasound signal, noise, balloon response, etc.) in such pressure records, a full waveform modeling is implemented and completed by infrasound ray tracing and additional data analysis. Here, we analyze the Stratéole-2 pressure data associated with two earthquakes (Garcia et al. Geophys. Res. Lett. 49(15):e98844, 2022) and compared these to full waveform simulations by SPECFEM2D-DG-LNS software. Even if our simulations do not precisely reproduce the waveform observed in the frequency range [0.05, 0.3] Hz, we show that the waveform presents more sensitivity to quake and internal structure parameters than to atmospheric structure, and that seismic surface wave dispersion is observed in balloon pressure records. The long-duration pressure oscillations observed after the main infrasonic signal cannot be fully reproduced by our one-dimensional input model even when source time function complexity and aftershocks are considered. These features are ascribed mainly to the complex vertical ground movements below the balloon and partly to late secondary infrasound arrivals excited by the interactions of seismic waves with the topography. These results enhance the advantages and limitations of quake-related infrasound observations on board terrestrial and planetary balloon platforms. Graphical Abstract

Abstract With the popularity of smart terminals, wearable electronic devices have shown great market prospects, especially high-sensitivity pressure sensors, which can monitor micro-stimuli and high-precision dynamic external stimuli, and will have an important impact on future functional development. Compressible flexible sensors have attracted wide attention due to their simple sensing mechanism and the advantages of light weight and convenience. Sensors with high sensitivity are very sensitive to pressure and can detect resistance/current changes under pressure, which has been widely studied. On this basis, this review focuses on analyzing the performance impact of device structure design strategies on high sensitivity pressure sensors. The design of structures can be divided into interface microstructures and three-dimensional framework structures. The preparation methods of various structures are introduced in detail, and the current research status and future development challenges are summarized.

Flexible pressure sensors with high sensitivity and linearity are highly desirable for robot sensing and human physiological signal detection. However, the current strategies for stabilizing axial microstructures (e.g., micro-pyramids) are mainly susceptible to structural stiffening during compression, thereby limiting the realization of high sensitivity and linearity. Here, we report a bending-induced non-equilibrium compression process that effectively enhances the compressibility of microstructures, thereby crucially improving the efficiency of interfacial area growth of electric double layer (EDL). Based on this principle, we fabricate an iontronic flexible pressure sensor with vertical graphene (VG) array electrodes. Ultra-high sensitivity (185.09 kPa−1) and linearity (R 2 = 0.9999) are realized over a wide pressure range (0.49 Pa–66.67 kPa). It also exhibits remarkable mechanical stability during compression and bending. The sensor is successfully employed in a robotic gripping task to recognize the targets of different materials and shapes based on a multilayer perception (MLP) neural network. It opens the door to realizing haptic sensing capabilities for robotic hands and prosthetic limbs. [ABSTRACT FROM AUTHOR]

Microstructures have been proved as crucial factors for the sensing performance of flexible pressure sensors. In this study, polypyrrole (PPy)/sunflower pollen (SFP) (P/SFP) was prepared via the in situ growth of PPy on the surface of degreased SFP with a sea urchin-like microstructure; then, these P/SFP microspheres were sprayed onto a flat silk cocoon (FSC) to prepare a sensing layer P/SFP-FSC. PPy-FSC (P-FSC) was prepared as an electrode layer through the in situ polymerization of PPy on the FSC surface. The sensing layer P/SFP-FSC was placed between two P-FSC electrode layers to assemble a P/SFP-FSC pressure sensor together with a fork finger electrode. With 6 mg/cm2 of optimized sprayed P/SFP microspheres, the prepared flexible pressure sensor has a sensitivity of up to 0.128 KPa−1 in the range of 0–13.18 KPa and up to 0.13 KPa−1 in the range of 13.18–30.65 KPa, a fast response/recovery time (90 ms/80 ms), and a minimum detection limit as low as 40 Pa. This fabricated flexible P/SFP-FSC sensor can monitor human motion and can also be used for the encrypted transmission of important information via Morse code. In conclusion, the developed flexible P/SFP-FSC pressure sensor based on microstructure modification in this study shows good application prospects in the field of human–computer interaction and wearable electronic devices. [ABSTRACT FROM AUTHOR]

Multiple factors stimulate human beings in their daily lives, but uniformly collecting these signals is challenging. This study proposes a physically cross‐linked method that employs hydrogen bonding interactions to prepare poly(vinyl alcohol)/perylene imide (PVA/PI) hydrogels. The prepared PVA/PI hydrogels demonstrate favorable compressive strength (45–75 kPa) and adhesion properties. At room temperature, elongation reaches approximately 400%. Additionally, the PVA/PI hydrogels exhibit strong mechanical properties, with a maximum elongation of 200%, and high ionic‐electronic conductivity of 29.6 S m−1, even after being soaked in a 2 M HCl solution for 24 h. The water‐soluble PI in the PVA/PI hydrogels is environmentally responsive, resulting in a current response time of 100 ms under 365 nm irradiation, as well as reversible fluorescence changes across different pH levels. Both the PVA5/PI1 and PVA5/PI1/HCl2 (the concentrations were 5 wt%, 1 mg mL−1 and 2 mol L−1, respectively) hydrogels demonstrate high sensitivity (0.49 and 7.88 kPa−1) and a wide pressure monitoring range (0.088–30.67 kPa and 0.088–18.67 kPa, respectively) as pressure sensors. The first developed recyclable PVA/PI hydrogel shows promise for use in wearable sensing devices and is expected to be applied in complex environments. [ABSTRACT FROM AUTHOR]

Flexible pressure sensors are valuable in applications such as electronic skin, smart robots, artificial prosthetics, and wearable electronics. In this study, a fully packaged, flexible, self‐powered, long‐term stable sensor array based on piezoelectrets is developed for pressure monitoring. A pressure sensor with a microcavity structure and a thickness of 500 µm achieved an impressive piezoelectric coefficient of 23.8 pC N−1 and a fast response time of 93 ms. The sensor yielded an output voltage of 0.26 V when subjected to a force using 0.3 g soybeans, and it displayed a remarkable linear relationship (R2 = 0.992) between force and electricity with pressure ranging from 1.4 to 13.6 N and a sensitivity of 9 mV N−1. Real‐time monitoring of sound vibration, radial artery pulse, and finger movement is demonstrated along with the successful recording of dynamic pressure changes within the porcine knee joint. It holds potential for fields such as monitoring pressure changes in the movement of human bodies and robotics and can contribute significantly to pressure assessment during total knee replacement. [ABSTRACT FROM AUTHOR]

With the development of technology, people's demand for pressure sensors with high sensitivity and a wide working range is increasing. An effective way to achieve this goal is simulating human skin. Herein, we propose a facile, low-cost, and reproducible method for preparing a skin-like multi-layer flexible pressure sensor (MFPS) device with high sensitivity (5.51 kPa−1 from 0 to 30 kPa) and wide working pressure range (0–200 kPa) by assembling carbonized fabrics and micro-wrinkle-structured Ag@rGO electrodes layer by layer. In addition, the highly imitated skin structure also provides the device with an extremely short response time (60/90 ms) and stable durability (over 3000 cycles). Importantly, we integrated multiple sensor devices into gloves to monitor finger movements and behaviors. In summary, the skin-like MFPS device has significant potential for real-time monitoring of human activities in the field of flexible wearable electronics and human–machine interaction. [ABSTRACT FROM AUTHOR]

One of the diagnostic tool for clinical evaluation and disease diagnosis is a pulse waveform analysis. High fidelity radial artery pulse waveforms have been investigated in clinical research to compute central aortic pressure, which has been demonstrated to be predictive of cardiovascular diseases. The radial artery must be inspected from several angles in order to obtain the best pulse waveform for estimate and diagnosis. In this study, we present the design and experimental testing of an optical sensor based on Fiber Bragg Gratings (FBG). A 3D printed device along with the FBG is used to measure the radial artery pulses. The proposed sensor is used for the purpose of quantifying the radial artery pulse waveform across major pulse position point. The suggested optical sensing system can measure the pulse signal with good accuracy. The main characteristic parameters of the pulse can then be retrieved from the processed signal for their use in clinical applications. By conducting experiments under the direction of medical experts, the pulse signals are measured. In order to experimentally validate the sensor, we used it to detect the pulse waveforms at Guan position of the wrist's radial artery in accordance with the diagnostic standards. The findings show that combining optical technologies for physiological monitoring and radial artery pulse waveform monitoring using FBG in clinical applications are highly feasible. [ABSTRACT FROM AUTHOR]

Acoustic waves generated by seismic waves contain information on the internal structure of planets, and can be sensed by pressure sensors onboard high-altitude balloons. To identify the various contributions (infrasound signal, noise, balloon response, etc.) in such pressure records, a full waveform modeling is implemented and completed by infrasound ray tracing and additional data analysis. Here, we analyze the Stratéole-2 pressure data associated with two earthquakes (Garcia et al. Geophys. Res. Lett. 49(15):e98844, 2022) and compared these to full waveform simulations by SPECFEM2D-DG-LNS software. Even if our simulations do not precisely reproduce the waveform observed in the frequency range [0.05, 0.3] Hz, we show that the waveform presents more sensitivity to quake and internal structure parameters than to atmospheric structure, and that seismic surface wave dispersion is observed in balloon pressure records. The long-duration pressure oscillations observed after the main infrasonic signal cannot be fully reproduced by our one-dimensional input model even when source time function complexity and aftershocks are considered. These features are ascribed mainly to the complex vertical ground movements below the balloon and partly to late secondary infrasound arrivals excited by the interactions of seismic waves with the topography. These results enhance the advantages and limitations of quake-related infrasound observations on board terrestrial and planetary balloon platforms. [ABSTRACT FROM AUTHOR]