scholarly journals Single-Layer Pressure Textile Sensors with Woven Conductive Yarn Circuit

2020 ◽  
Vol 10 (8) ◽  
pp. 2877 ◽  
Author(s):  
Gaeul Kim ◽  
Chi Cuong Vu ◽  
Jooyong Kim

Today, e-textiles have become a fundamental trend in wearable devices. Fabric pressure sensors, as a part of e-textiles, have also received much interest from many researchers all over the world. However, most of the pressure sensors are made of electronic fibers and composed of many layers, including an intermediate layer for sensing the pressure. This paper proposes the model of a single layer pressure sensor with electrodes and conductive fibers intertwined. The plan dimensions of the fabricated sensors are 14 x 14 mm, and the thickness is 0.4 mm. The whole area of the sensor is the pressure-sensitive point. As expected, results demonstrate an electrical resistance change from 283 Ω at the unload pressure to 158 Ω at the load pressure. Besides, sensors have a fast response time (50 ms) and small hysteresis (5.5%). The hysteresis will increase according to the pressure and loading distance, but the change of sensor loading distance is very small. Moreover, the single-layer pressure sensors also show high durability under many working cycles (20,000 cycles) or washing times (50 times). The single-layer pressure sensor is very thin and more flexible than the multi-layer pressure sensor. The structure of this sensor is also expected to bring great benefits to wearable technology in the future.

Nanoscale ◽  
2018 ◽  
Vol 10 (22) ◽  
pp. 10691-10698 ◽  
Author(s):  
Zhihui Wang ◽  
Ling Zhang ◽  
Jin Liu ◽  
Hao Jiang ◽  
Chunzhong Li

Flexible pressure sensors with interlocked hemispheric microstructures are prepared by a novel breath figure strategy. The subtle microstructure remarkably improves the sensitivity and pressure sensing range of the pressure sensor.


Sensors ◽  
2020 ◽  
Vol 20 (22) ◽  
pp. 6588
Author(s):  
Jun Ho Lee ◽  
Jae Sang Heo ◽  
Keon Woo Lee ◽  
Jae Cheol Shin ◽  
Jeong-Wan Jo ◽  
...  

For wearable health monitoring systems and soft robotics, stretchable/flexible pressure sensors have continuously drawn attention owing to a wide range of potential applications such as the detection of human physiological and activity signals, and electronic skin (e-skin). Here, we demonstrated a highly stretchable pressure sensor using silver nanowires (AgNWs) and photo-patternable polyurethane acrylate (PUA). In particular, the characteristics of the pressure sensors could be moderately controlled through a micro-patterned hole structure in the PUA spacer and size-designs of the patterned hole area. With the structural-tuning strategies, adequate control of the site-specific sensitivity in the range of 47~83 kPa−1 and in the sensing range from 0.1 to 20 kPa was achieved. Moreover, stacked AgNW/PUA/AgNW (APA) structural designed pressure sensors with mixed hole sizes of 10/200 µm and spacer thickness of 800 µm exhibited high sensitivity (~171.5 kPa−1) in the pressure sensing range of 0~20 kPa, fast response (100~110 ms), and high stretchability (40%). From the results, we envision that the effective structural-tuning strategy capable of controlling the sensing properties of the APA pressure sensor would be employed in a large-area stretchable pressure sensor system, which needs site-specific sensing properties, providing monolithic implementation by simply arranging appropriate micro-patterned hole architectures.


Sensors ◽  
2019 ◽  
Vol 19 (10) ◽  
pp. 2223 ◽  
Author(s):  
Mengwei Li ◽  
Teng Zhang ◽  
Pengcheng Wang ◽  
Minghao Li ◽  
Junqiang Wang ◽  
...  

Temperature is a significant factor in the application of graphene-based pressure sensors. The influence of temperature on graphene pressure sensors is twofold: an increase in temperature causes the substrates of graphene pressure sensors to thermally expand, and thus, the graphene membrane is stretched, leading to an increase in the device resistance; an increase in temperature also causes a change in the graphene electrophonon coupling, resulting in a decrease in device resistance. To investigate which effect dominates the influence of temperature on the pressure sensor based on the graphene–boron nitride (BN) heterostructure proposed in our previous work, the temperature characteristics of two BN/graphene/BN heterostructures with and without a microcavity beneath them were analyzed in the temperature range 30–150 °C. Experimental results showed that the resistance of the BN/graphene/BN heterostructure with a microcavity increased with the increase in temperature, and the temperature coefficient was up to 0.25%°C−1, indicating the considerable influence of thermal expansion in such devices. In contrast, with an increase in temperature, the resistance of the BN/graphene/BN heterostructure without a microcavity decreased with a temperature coefficient of −0.16%°C−1. The linearity of the resistance change rate (ΔR/R)–temperature curve of the BN/graphene/BN heterostructure without a microcavity was better than that of the BN/graphene/BN heterostructure with a microcavity. These results indicate that the influence of temperature on the pressure sensors based on BN/graphene/BN heterostructures should be considered, especially for devices with pressure microcavities. BN/graphene/BN heterostructures without microcavities can be used as high-performance temperature sensors.


2017 ◽  
Vol 31 (05) ◽  
pp. 1750046
Author(s):  
Wu Zhou ◽  
Dong Wang ◽  
Huijun Yu ◽  
Bei Peng

Rectangular diaphragm is commonly used as a pressure sensitive component in MEMS pressure sensors. Its deformation under applied pressure directly determines the performance of micro-devices, accurately acquiring the pressure–deflection relationship, therefore, plays a significant role in pressure sensor design. This paper analyzes the deflection of an isotropic rectangular diaphragm under combined effects of loads. The model is regarded as a clamped plate with full surface uniform load and partially uniform load applied on its opposite sides. The full surface uniform load stands for the external measured pressure. The partial load is used to approximate the opposite reaction of the silicon island which is planted on the diaphragm to amplify the deformation displacement, thus to improve the sensitivity of the pressure sensor. Superposition method is proposed to calculate the diaphragm deflections. This method considers separately the actions of loads applied on the simple supported plate and moments distributed on edges. Considering the boundary condition of all edges clamped, the moments are constructed to eliminate the boundary rotations caused by lateral load. The diaphragm’s deflection is computed by superposing deflections which produced by loads applied on the simple supported plate and moments distributed on edges. This method provides higher calculation accuracy than Galerkin variational method, and it is used to analyze the influence factors of the diaphragm’s deflection, includes aspect ratio, thickness and the applied force area of the diaphragm.


Nanoscale ◽  
2021 ◽  
Author(s):  
Yachu Zhang ◽  
Han Lin ◽  
Fei Meng ◽  
Huai Liu ◽  
David Mesa ◽  
...  

Wearable and highly sensitive pressure sensors are of great importance for robotics, health monitoring and biomedical applications. Simultaneously achieving high sensitivity within a broad working range, fast response time (within...


2021 ◽  
Vol 31 (12) ◽  
pp. 124002
Author(s):  
Jie Yu ◽  
Yulan Lu ◽  
Deyong Chen ◽  
Junbo Wang ◽  
Jian Chen ◽  
...  

Abstract High-pressure sensors enable expansive demands in ocean sciences, industrial controls, and oil explorations. Successful sensor realized in piezoresistive high-pressure sensors which suffer from the key issue of compromised accuracies due to serious temperature drifts. Herein, this paper presents a high accuracy resonant high-pressure sensor with the pressure range of 70 MPa. Different from conventional resonant high-pressure sensor, the developed sensor utilized a dual-resonator-cavity design to minimize temperature disturbances and improve the pressure sensitivities. Besides, four circle cavities were used to maintain a high vacuum level for resonators after anodic bonding process. In details, Dual resonators, which is parallelly placed in the tensile and compressive stresses areas of a rectangular pressure sensitive diaphragm, are separated vacuum-packaged in the parallel dual cavities. Thus, pressure under measurement bends the pressure sensitive diaphragm, producing an increased pressure sensitivity and a decreased temperature sensitivity by the differential outputs of the dual resonators. Parameterized mathematical models of the sensor were established and the parameters of the models were optimized to adjust the pressure sensitivities and the temperature sensitivities of the sensor. Simplified deep reactive ion etching was used to form the sensing structure of the sensor and only once anodic bonding was used to form vacuum packaging for the dual resonators. Experimental results confirmed that the Q values of the resonators were higher than 32 000. Besides, the temperature sensitivity of the sensor was reduced from 44 Hz °C−1 (494 ppm °C−1) to 1 Hz °C−1 (11 ppm °C−1) by the differential outputs of the dual resonators in the temperature range of −10 °C–60 °C under the pressure of 1000 kPa. In addition, the accuracy of the sensor was better than 0.02% FS within the pressure range of 110–6500 kPa and the temperature range of −10 °C–60 °C by using a polynomial algorithm.


2021 ◽  
Vol 12 (1) ◽  
Author(s):  
Xiu-man Wang ◽  
Lu-qi Tao ◽  
Min Yuan ◽  
Ze-ping Wang ◽  
Jiabing Yu ◽  
...  

AbstractSensitivity and pressure range are two significant parameters of pressure sensors. Existing pressure sensors have difficulty achieving both high sensitivity and a wide pressure range. Therefore, we propose a new pressure sensor with a ternary nanocomposite Fe2O3/C@SnO2. The sea urchin-like Fe2O3 structure promotes signal transduction and protects Fe2O3 needles from mechanical breaking, while the acetylene carbon black improves the conductivity of Fe2O3. Moreover, one part of the SnO2 nanoparticles adheres to the surfaces of Fe2O3 needles and forms Fe2O3/SnO2 heterostructures, while its other part disperses into the carbon layer to form SnO2@C structure. Collectively, the synergistic effects of the three structures (Fe2O3/C, Fe2O3/SnO2 and SnO2@C) improves on the limited pressure response range of a single structure. The experimental results demonstrate that the Fe2O3/C@SnO2 pressure sensor exhibits high sensitivity (680 kPa−1), fast response (10 ms), broad range (up to 150 kPa), and good reproducibility (over 3500 cycles under a pressure of 110 kPa), implying that the new pressure sensor has wide application prospects especially in wearable electronic devices and health monitoring.


2016 ◽  
Vol 4 (27) ◽  
pp. 10435-10443 ◽  
Author(s):  
Banseok You ◽  
Chul Jong Han ◽  
Youngmin Kim ◽  
Byeong-Kwon Ju ◽  
Jong-Woong Kim

A new approach to the fabrication of a transparent, stretchable and pressure-sensitive capacitor was developed by employing a single layer of Ag nanowire-based electrodes and a transparent, stretchable polymer.


2020 ◽  
Author(s):  
Yunlu Lian ◽  
He Yu ◽  
Mingyuan Wang ◽  
Xiaonan Yang ◽  
Hefei Zhang

Abstract Flexible pressure sensors have attracted increasing attention due to their potential applications in wearable human health monitoring and care systems. Herein, we present a facile approach for fabricating all-textile-based piezoresistive pressure sensor with integrated Ag nanowire-coated fabrics. It fully takes advantage of the synergistic effect of the fiber/yarn/fabric multi-level contacts, leading to the ultrahigh sensitivity of 3.24×10 5 kPa −1 at 0–10 kPa and 2.16×10 4 kPa −1 at 10–100 kPa, respectively. Furthermore, the device achieved a fast response/relaxation time (32/24 ms), and a high stability (>1000 loading/unloading cycles). Thus, such all-textile pressure sensor with high performance is expected to be applicable in the fields of smart cloths, activity monitoring and healthcare device.


2020 ◽  
Author(s):  
Xiu Wang ◽  
Lu-Qi Tao ◽  
Min Yuan ◽  
Ze-Ping Wang ◽  
Jiabing Yu ◽  
...  

Abstract Sensitivity and pressure range are two significant parameters of pressure sensors. The existing pressure sensors are difficult to achieve both high sensitivity and a wide pressure range. In this regard, we proposed a new pressure sensor with a ternary nanocomposite Fe2O3/C@SnO2. Notably, the sea urchin-like Fe2O3 structure promoted signal transduction and protected Fe2O3 needles from mechanical breaking; while, acetylene carbon black improved the conductivity of Fe2O3. Moreover, one part of SnO2 nanoparticles adhered to the surface of Fe2O3 needles and formed Fe2O3/SnO2 heterostructures whereas its other part of nanoparticles dispersed into the carbon layer and formed SnO2@C structures. Collectively, the synergy of the three structures (Fe2O3/C, Fe2O3/SnO2 and SnO2@C) improved the limited pressure response range of a single structure. The experimental results demonstrated that the Fe2O3/C@SnO2 pressure sensor exhibits high sensitivity (680 kPa-1), fast response (10 ms), broad range (up to 150 kPa), and good reproducibility (over 3500 cycles under a pressure of 110 kPa). This implies that the new pressure sensor has wide application prospects especially in wearable electronic devices and health monitoring.


Sign in / Sign up

Export Citation Format

Share Document