Flexible Pressure Sensors Based on Bionic Microstructures: From Plants to Animals

This paper reports on the study of microporous polydimethylsiloxane (PDMS) foams as a highly deformable dielectric material used in the composition of flexible capacitive pressure sensors dedicated to wearable use. A fabrication process allowing the porosity of the foams to be adjusted was proposed and the fabricated foams were characterized. Then, elementary capacitive pressure sensors (15 × 15 mm2 square shaped electrodes) were elaborated with fabricated foams (5 mm or 10 mm thick) and were electromechanically characterized. Since the sensor responses under load are strongly non-linear, a behavioral non-linear model (first order exponential) was proposed, adjusted to the experimental data, and used to objectively estimate the sensor performances in terms of sensitivity and measurement range. The main conclusions of this study are that the porosity of the PDMS foams can be adjusted through the sugar:PDMS volume ratio and the size of sugar crystals used to fabricate the foams. Additionally, the porosity of the foams significantly modified the sensor performances. Indeed, compared to bulk PDMS sensors of the same size, the sensitivity of porous PDMS sensors could be multiplied by a factor up to 100 (the sensitivity is 0.14 %.kPa−1 for a bulk PDMS sensor and up to 13.7 %.kPa−1 for a porous PDMS sensor of the same dimensions), while the measurement range was reduced from a factor of 2 to 3 (from 594 kPa for a bulk PDMS sensor down to between 255 and 177 kPa for a PDMS foam sensor of the same dimensions, according to the porosity). This study opens the way to the design and fabrication of wearable flexible pressure sensors with adjustable performances through the control of the porosity of the fabricated PDMS foams.

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Binary Spiky/Spherical Nanoparticle Films with Hierarchical Micro/Nanostructures for High-Performance Flexible Pressure Sensors

ACS Applied Materials & Interfaces ◽

10.1021/acsami.0c18543 ◽

2020 ◽

Vol 12 (52) ◽

pp. 58403-58411

Author(s):

Young-Ryul Kim ◽

Minsoo P. Kim ◽

Jonghwa Park ◽

Youngoh Lee ◽

Sujoy Kumar Ghosh ◽

...

Keyword(s):

High Performance ◽

Pressure Sensors ◽

Nanoparticle Films ◽

Flexible Pressure Sensors

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Flexible pressure sensing film based on ultra-sensitive SWCNT/PDMS spheres for monitoring human pulse signals

Journal of Materials Chemistry B ◽

10.1039/c5tb00653h ◽

2015 ◽

Vol 3 (27) ◽

pp. 5436-5441 ◽

Cited By ~ 29

Author(s):

Yan-Long Tai ◽

Zhen-Guo Yang

Keyword(s):

Pressure Sensors ◽

Pressure Sensing ◽

Prosthetic Limbs ◽

Electronic Skin ◽

Essential Components ◽

Biomedical Diagnostics ◽

Healthcare Monitoring ◽

Flexible Pressure Sensors ◽

Human Healthcare

Flexible pressure sensors are essential components of an electronic skin for future attractive applications ranging from human healthcare monitoring to biomedical diagnostics to robotic skins to prosthetic limbs.

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Multi length scale hierarchical architecture overcoming pressure sensing range-speed tradeoff for flexible pressure sensors

Journal of Materials Chemistry C ◽

10.1039/d1tc03753f ◽

2021 ◽

Author(s):

Qiong Tian ◽

Wenrong Yan ◽

Tianding CHEN ◽

Derek Ho

Keyword(s):

Biomedical Applications ◽

Pressure Sensors ◽

Human Machine Interface ◽

Hierarchical Architecture ◽

Soft Robotics ◽

Length Scale ◽

Pressure Sensing ◽

Sensing Range ◽

Machine Interface ◽

Flexible Pressure Sensors

Pressure sensing electronics have gained great attention in human-machine interface, soft robotics, and wearable biomedical applications. However, existing sensor architectures are inadequate in overcoming the classic tradeoff between sensing range,...

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Oxidized Ti3C2Tx film-based high-performance flexible pressure sensors

Journal of Physics D Applied Physics ◽

10.1088/1361-6463/ac0ca1 ◽

2021 ◽

Author(s):

Xiyao Fu ◽

Depeng Wang ◽

Lili Wang ◽

Hao Xu ◽

Valerii Shulga ◽

...

Keyword(s):

High Performance ◽

Pressure Sensors ◽

Flexible Pressure Sensors

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Highly sensitive and stable flexible pressure sensors with micro-structured electrodes

Journal of Alloys and Compounds ◽

10.1016/j.jallcom.2016.12.414 ◽

2017 ◽

Vol 699 ◽

pp. 824-831 ◽

Cited By ~ 22

Author(s):

Yong Quan ◽

Xiongbang Wei ◽

Lun Xiao ◽

Tao Wu ◽

Hanying Pang ◽

...

Keyword(s):

Pressure Sensors ◽

Highly Sensitive ◽

Flexible Pressure Sensors

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Flexible Pressure Sensors with Wide Linearity Range and High Sensitivity Based on Selective Laser Sintering 3D Printing

Advanced Materials Technologies ◽

10.1002/admt.201900679 ◽

2019 ◽

Vol 4 (12) ◽

pp. 1900679 ◽

Cited By ~ 4

Author(s):

Tong Zhang ◽

Zhaoyang Li ◽

Kun Li ◽

Xiaoniu Yang

Keyword(s):

3D Printing ◽

Selective Laser Sintering ◽

Pressure Sensors ◽

High Sensitivity ◽

Laser Sintering ◽

Linearity Range ◽

Flexible Pressure Sensors

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Rational Design of a Novel Highly Folding-tolerable Edgewo-rthia Chrysantha Lindi-derived Substrate for Versatile Flexible Pressure Sensors

10.21203/rs.3.rs-1113986/v1 ◽

2021 ◽

Author(s):

Danning Fu ◽

Ruibin Wang ◽

Rendang Yang

Keyword(s):

Flexible Electronics ◽

Rational Design ◽

Silver Nanowires ◽

Pressure Sensors ◽

Elbow Flexion ◽

Gauge Factor ◽

Layer By Layer ◽

The Novel ◽

Mechanical And Electrical Properties ◽

Flexible Pressure Sensors

Abstract Cellulose-based composites with superior mechanical and electrical properties are highly desirable for a sustainable and multifunctional substrate of flexible electronics. However, their practical application is hindered by the lack of superflexible cellulose-based composites to fabricate ingenious flexible electronics with considerable robustness. Here, cellulose derived from underutilized biomass (Edgewo-rthia chrysantha Lindi, ERCL) was composited with highly-conductive silver nanowires (AgNWs) through a general papermaking process. Benefiting from the interactions between cellulose and AgNWs including hydrogen bonding and van der Waals force, the composite presented superb electrical conductivity (> 27000 S/m) and flexibility (folding times ≥1110). By employing it as the substrate of flexible pressure sensors (FPSs) through layer-by-layer assembly, improved sensitivity (Gauge Factor=846.4), rapid response (0.44 s), and excellent stability (≥2000 folding cycles) were demonstrated. Impressively, the novel FPS could monitor human motions, including finger bending, elbow flexion, speaking, and pulse, suggesting its great potentials in emerging flexible electronics.

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Polyaniline Nanofiber Wrapped Fabric for High Performance Flexible Pressure Sensors

Polymers ◽

10.3390/polym11071120 ◽

2019 ◽

Vol 11 (7) ◽

pp. 1120 ◽

Cited By ~ 12

Author(s):

Kangning Liu ◽

Ziqiang Zhou ◽

Xingwu Yan ◽

Xiang Meng ◽

Hua Tang ◽

...

Keyword(s):

High Performance ◽

Rational Design ◽

Active Material ◽

Pressure Sensors ◽

Linear Range ◽

Superior Performance ◽

Wearable Electronics ◽

Wide Linear Range ◽

Polyaniline Nanofiber ◽

Flexible Pressure Sensors

The rational design of high-performance flexible pressure sensors with both high sensitivity and wide linear range attracts great attention because of their potential applications in wearable electronics and human-machine interfaces. Here, polyaniline nanofiber wrapped nonwoven fabric was used as the active material to construct high performance, flexible, all fabric pressure sensors with a bottom interdigitated textile electrode. Due to the unique hierarchical structures, large surface roughness of the polyaniline coated fabric and high conductivity of the interdigitated textile electrodes, the obtained pressure sensor shows superior performance, including ultrahigh sensitivity of 46.48 kPa−1 in a wide linear range (<4.5 kPa), rapid response/relaxation time (7/16 ms) and low detection limit (0.46 Pa). Based on these merits, the practical applications in monitoring human physiological signals and detecting spatial distribution of subtle pressure are demonstrated, showing its potential for health monitoring as wearable electronics.

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