we bolted BGK-FBG-4150 sensors on wireless strain sensors on the specimen the specimen instead of welding on it, with 502 plastic. This four kinds of we pasted MOI FBG sensors on the sensors are arranged in the middle specimen with the help of AB glue, and position of the specimen in order to we pasted FLA-5-11 strain sensor and ensure the unity, as shown in Fig.1;

This paper presents a wearable hand module which was made of five fiber Bragg grating (FBG) strain sensor and algorithms to achieve high accuracy even when worn on different hand sizes of users. For real-time calculation with high accuracy, FBG strain sensors move continuously according to the size of the hand and the bending of the joint. Representatively, four algorithms were proposed; point strain (PTS), area summation (AREA), proportional summation (PS), and PS/interference (PS/I or PS/I_ α ). For more accurate and efficient assessments, 3D printed hand replica with different finger sizes was adopted and quantitative evaluations were performed for index~little fingers (77 to 117 mm) and thumb (68~78 mm). For index~little fingers, the optimized algorithms were PS and PS/I_ α . For thumb, the optimized algorithms were PS/I_ α and AREA. The average error angle of the wearable hand module was observed to be 0.47 ± 2.51° and mean absolute error (MAE) was achieved at 1.63 ± 1.97°. These results showed that more accurate hand modules than other glove modules applied to different hand sizes can be manufactured using FBG strain sensors which move continuously and algorithms for tracking this movable FBG sensors.

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Development of Highly Sensitive Strain Sensor Using Area-Arrayed Graphene Nanoribbons

Nanomaterials ◽

10.3390/nano11071701 ◽

2021 ◽

Vol 11 (7) ◽

pp. 1701

Author(s):

Ken Suzuki ◽

Ryohei Nakagawa ◽

Qinqiang Zhang ◽

Hideo Miura

Keyword(s):

Graphene Nanoribbons ◽

Strain Sensor ◽

Strain Sensors ◽

Sensitive Strain ◽

Bending Test ◽

Gauge Factor ◽

Four Point Bending ◽

Current Voltage ◽

Highly Sensitive ◽

Current Voltage Relationship

In this study, a basic design of area-arrayed graphene nanoribbon (GNR) strain sensors was proposed to realize the next generation of strain sensors. To fabricate the area-arrayed GNRs, a top-down approach was employed, in which GNRs were cut out from a large graphene sheet using an electron beam lithography technique. GNRs with widths of 400 nm, 300 nm, 200 nm, and 50 nm were fabricated, and their current-voltage characteristics were evaluated. The current values of GNRs with widths of 200 nm and above increased linearly with increasing applied voltage, indicating that these GNRs were metallic conductors and a good ohmic junction was formed between graphene and the electrode. There were two types of GNRs with a width of 50 nm, one with a linear current–voltage relationship and the other with a nonlinear one. We evaluated the strain sensitivity of the 50 nm GNR exhibiting metallic conduction by applying a four-point bending test, and found that the gauge factor of this GNR was about 50. Thus, GNRs with a width of about 50 nm can be used to realize a highly sensitive strain sensor.

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Strain Sensor Based on Biological Nanomaterial

Engineering Proceedings ◽

10.3390/i3s2021dresden-10115 ◽

2021 ◽

Vol 6 (1) ◽

pp. 23

Author(s):

Levan P. Ichkitidze ◽

Alexander Yu. Gerasimenko ◽

Dmitry V. Telyshev ◽

Eugeny P. Kitsyuk ◽

Vladimir A. Petukhov ◽

...

Keyword(s):

Screen Printing ◽

Respiratory Diseases ◽

Specific Conductivity ◽

Strain Sensor ◽

Aqueous Dispersion ◽

Strain Sensors ◽

Bending Angle ◽

Multi Walled Carbon Nanotubes ◽

Number Of Cycles ◽

Walled Carbon Nanotubes

We investigated a prototype of a strain sensor based on the layers of a bionanomaterial containing bovine serum albumin (BSA matrix) and multi-walled carbon nanotubes (MWCNT filler). The aqueous dispersion of 25 wt.% BSA/0.3 wt.% MWCNT was applied by screen printing onto flexible polyethylene terephthalate substrates. After drying the layers by laser irradiation (~970 nm), various parameters of the layers were controlled, i.e., resistance R, bending angle θ, number of cycles n, and measurement time. One measurement cycle corresponded to a change within the range θ = ±150°. The layers of the BSA/MWCNT bionanomaterial had dimensions of (15 ÷ 20) mm × (8 ÷ 10) mm × (0.5 ÷ 1. 5) µm. The dependences of resistance R on the bending angle θ were similar for all layers at θ = ±30, and the R(θ) curves represented approximate linear dependences (with an error of ≤ 10%); beyond this range, the dependences became nonlinear. The following quantitative values were obtained for the investigated strain sensor: specific conductivity ~1 ÷ 10 S/m, linear strain sensitivity ~160, and bending sensitivity 1.0 ÷ 1.5%/°. These results are high. The examined layers of the bionanomaterial BSA/MWCNT as a strain sensor are of particular interest for medical practice. In particular, strain sensors can be implemented by applying a water dispersion of nanomaterials to human skin using a 3D printer for monitoring movements (arms and blinking) and the detection of signs of pathology (dysphagia, respiratory diseases, angina, etc.).

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A Novel Textile Stitch-Based Strain Sensor for Wearable End Users

Materials ◽

10.3390/ma12091469 ◽

2019 ◽

Vol 12 (9) ◽

pp. 1469 ◽

Cited By ~ 10

Author(s):

Orathai Tangsirinaruenart ◽

George Stylios

Keyword(s):

Mechanical Properties ◽

Electrical Resistance ◽

Body Movement ◽

Strain Sensor ◽

Strain Sensors ◽

Gauge Factor ◽

Heart Monitoring ◽

Textile Sensors ◽

Good Repeatability ◽

The Ideal

This research presents an investigation of novel textile-based strain sensors and evaluates their performance. The electrical resistance and mechanical properties of seven different textile sensors were measured. The sensors are made up of a conductive thread, composed of silver plated nylon 117/17 2-ply, 33 tex and 234/34 4-ply, 92 tex and formed in different stitch structures (304, 406, 506, 605), and sewn directly onto a knit fabric substrate (4.44 tex/2 ply, with 2.22, 4.44 and 7.78 tex spandex and 7.78 tex/2 ply, with 2.22 and 4.44 tex spandex). Analysis of the effects of elongation with respect to resistance indicated the ideal configuration for electrical properties, especially electrical sensitivity and repeatability. The optimum linear working range of the sensor with minimal hysteresis was found, and the sensor’s gauge factor indicated that the sensitivity of the sensor varied significantly with repeating cycles. The electrical resistance of the various stitch structures changed significantly, while the amount of drift remained negligible. Stitch 304 2-ply was found to be the most suitable for strain movement. This sensor has a wide working range, well past 50%, and linearity (R2 is 0.984), low hysteresis (6.25% ΔR), good gauge factor (1.61), and baseline resistance (125 Ω), as well as good repeatability (drift in R2 is −0.0073). The stitch-based sensor developed in this research is expected to find applications in garments as wearables for physiological wellbeing monitoring such as body movement, heart monitoring, and limb articulation measurement.

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Structural Reinforcement Effect of a Flexible Strain Sensor Integrated with Pneumatic Balloon Actuators for Soft Microrobot Fingers

Micromachines ◽

10.3390/mi12040395 ◽

2021 ◽

Vol 12 (4) ◽

pp. 395

Author(s):

Satoshi Konishi ◽

Fuminari Mori ◽

Ayano Shimizu ◽

Akiya Hirata

Keyword(s):

Liquid Metal ◽

Strain Sensor ◽

Strain Sensors ◽

Original Performance ◽

Sensors And Actuators ◽

Parylene C ◽

Structural Reinforcement ◽

Effective Combination ◽

Metal Strain ◽

Flexible Strain Sensor

Motion capture of a robot and tactile sensing for a robot require sensors. Strain sensors are used to detect bending deformation of the robot finger and to sense the force from an object. It is important to introduce sensors in effective combination with actuators without affecting the original performance of the robot. We are interested in the improvement of flexible strain sensors integrated into soft microrobot fingers using a pneumatic balloon actuator (PBA). A strain sensor using a microchannel filled with liquid metal was developed for soft PBAs by considering the compatibility of sensors and actuators. Inflatable deformation generated by PBAs, however, was found to affect sensor characteristics. This paper presents structural reinforcement of a liquid metal-based sensor to solve this problem. Parylene C film was deposited into a microchannel to reinforce its structure against the inflatable deformation caused by a PBA. Parylene C deposition into a microchannel suppressed the interference of inflatable deformation. The proposed method enables the effective combination of soft PBAs and a flexible liquid metal strain sensor for use in microrobot fingers.

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Research on the Performance of Strain Sensors Applied to Bridges

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.875-877.680 ◽

2014 ◽

Vol 875-877 ◽

pp. 680-684

Author(s):

Zhi Liu ◽

Jing Liu ◽

Shu Ri Cai

Keyword(s):

Health Monitoring ◽

Performance Test ◽

Strain Sensor ◽

Safety Monitoring ◽

Strain Sensors ◽

Great Role ◽

Temperature Drift ◽

Short Life ◽

Test Analysis ◽

Health Monitoring System

Strengthening safety monitoring of bridges during service time and improving the capability of emergency support have become the priority of the development of China’s present transportation system. Strain sensors play a great role in bridge detection and health monitoring system. In order to overcome disadvantages of traditional resistance strain sensors, such as big temperature drift, short life and inadaptability in the environment of low temperature and humidity, new arch strain sensors have been developed. This paper mainly discusses the structural and material characteristics of this sensor, as well as the performance test analysis of this strain sensor.

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Area-Arrayed Graphene Nano-Ribbon-Base Strain Sensor

Volume 10: Micro- and Nano-Systems Engineering and Packaging ◽

10.1115/imece2018-87277 ◽

2018 ◽

Cited By ~ 2

Author(s):

Ryohei Nakagawa ◽

Zhi Wang ◽

Ken Suzuki

Keyword(s):

Chemical Vapor Deposition ◽

Stress Concentration ◽

Health Monitoring ◽

Vapor Deposition ◽

Strain Sensor ◽

Chemical Vapor ◽

High Sensitivity ◽

Strain Sensors ◽

Chemical Vapor Deposition Method ◽

High Quality

Health monitoring devices using a strain sensor, which shows high sensitivity and large deformability, are strongly demanded due to further aging of society with fewer children. Conventional strain sensors, such as metallic strain gauges and semiconductive strain sensors, however, aren’t applicable to health monitoring because of their low sensitivity and deformability. In this study, fundamental design of area-arrayed graphene nano-ribbon (GNR) strain senor was proposed in order to fabricate next-generation strain sensor. The sensor was consisted of two sections, which are stress concentration section and stress detecting section. This structure can take full advantage of GNR’s properties. Moreover, high quality GNR fabrication process, which is one of the important process in the sensor, was developed by applying CVD (Chemical Vapor Deposition) method. Top-down approach was applied to fabricate the GNR. At first, in order to synthesize a high-quality graphene sheet, acetylene-based LPCVD (low pressure chemical vapor deposition) using a closed Cu foil was employed. After that, graphene was transferred silicon substrate and the quality was evaluated. The high quality graphene was transferred on the soft PDMS substrate and metallic electrodes were fabricated by applying MEMS technology. Area-arrayed fine pin structure was fabricated by using hard PDMS as a stress-concentration section. Finally, both sections were integrated to form a highly sensitive and large deformable pressure sensor. The strain sensitivity of the GNR-base sensor was also evaluated.

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A novel strain sensor using a microchannel embedded in PDMS

Journal of Biomedical Engineering and Informatics ◽

10.5430/jbei.v4n2p1 ◽

2018 ◽

Vol 4 (2) ◽

pp. 1 ◽

Cited By ~ 1

Author(s):

Angelica Campigotto ◽

Stephane Leahy ◽

Ayan Choudhury ◽

Guowei Zhao ◽

Yongjun Lai

Keyword(s):

Finite Element ◽

Rotation Angle ◽

Strain Sensor ◽

Element Model ◽

Strain Sensors ◽

Gauge Factor ◽

Sectional Area ◽

Cross Sectional ◽

Higher Sensitivity

A novel, inexpensive, and easy-to-use strain sensor using polydimethylsiloxane (PDMS) was developed. The sensor consists of a microchannel that is partially filled with a coloured liquid and embedded in a piece of PDMS. A finite element model was developed to optimize the geometry of the microchannel to achieve higher sensitivity. The highest gauge factor that was measured experimentally was 41. The gauge factor was affected by the microchannel’s square cross-sectional area, the number of basic units in the microchannel, and the inlet and outlet configuration. As a case study, the developed strain sensors were used to measure the rotation angle of the wrist and finger joints.

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Corrugated Photoactive Thin Films for Flexible Strain Sensor

Materials ◽

10.3390/ma11101970 ◽

2018 ◽

Vol 11 (10) ◽

pp. 1970 ◽

Cited By ~ 7

Author(s):

Donghyeon Ryu ◽

Alfred Mongare

Keyword(s):

Thin Film ◽

Thin Films ◽

Electrical Properties ◽

Tensile Strain ◽

Strain Sensor ◽

Strain Sensors ◽

Optical And Electrical Properties ◽

Strain Sensing ◽

Dc Voltage ◽

Flexible Strain Sensor

In this study, a flexible strain sensor is devised using corrugated bilayer thin films consisting of poly(3-hexylthiophene) (P3HT) and poly(3,4-ethylenedioxythiophene)-polystyrene(sulfonate) (PEDOT:PSS). In previous studies, the P3HT-based photoactive non-corrugated thin film was shown to generate direct current (DC) under broadband light, and the generated DC voltage varied with applied tensile strain. Yet, the mechanical resiliency and strain sensing range of the P3HT-based thin film strain sensor were limited due to brittle non-corrugated thin film constituents. To address this issue, it is aimed to design a mechanically resilient strain sensor using corrugated thin film constituents. Buckling is induced to form corrugation in the thin films by applying pre-strain to the substrate, where the thin films are deposited, and releasing the pre-strain afterwards. It is known that corrugated thin film constituents exhibit different optical and electronic properties from non-corrugated ones. Therefore, to design the flexible strain sensor, it was studied to understand how the applied pre-strain and thickness of the PEDOT:PSS conductive thin film affects the optical and electrical properties. In addition, strain effect was investigated on the optical and electrical properties of the corrugated thin film constituents. Finally, flexible strain sensors are fabricated by following the design guideline, which is suggested from the studies on the corrugated thin film constituents, and the DC voltage strain sensing capability of the flexible strain sensors was validated. As a result, the flexible strain sensor exhibited a tensile strain sensing range up to 5% at a frequency up to 15 Hz with a maximum gauge factor ~7.

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Comparison of Digital Image Correlation (DIC) Technique with Nanomaterial-Based Sensor for the Analysis of Strain Measurements

International Journal of Nanoscience ◽

10.1142/s0219581x21500320 ◽

2021 ◽

pp. 2150032

Author(s):

A. Deepak ◽

D. F. L. Jenkins

Keyword(s):

Digital Image Correlation ◽

Digital Image ◽

Standard Specimen ◽

Strain Sensor ◽

Constant Load ◽

Strain Sensors ◽

Image Correlation ◽

Strain Measurements ◽

American Society ◽

Dic Technique

Digital Image Correlation (DIC) techniques can be used to visually map and measure strain in materials such as metals and metallic alloys. The strain induced in an American Society for Testing and Materials (ASTMs) standard specimen can be measured using a DIC technique. Image patterns indicating the localized strain variations as a function of time for the constant load applied were also obtained. Results obtained using the DIC technique were more accurate compared to conventional strain sensors. DIC results were also compared with nanomaterial-based strain sensor output. Localized strain induced in the material can be visualized and quantified analytically using DIC.

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