Evaporation of Ti/Cr/Ti Multilayer on Flexible Polyimide and Its Application for Strain Sensor

A flexible Ti/Cr/Ti multilayer strain gauge have been successfully developed based on polyimide substrate. The pure Ti metal strain gauge have shown the hysteresis phenomenon at the relationship between resistance and strain during tensile test. The experimental results of multilayer strain gauge show that adding Cr interlayer can improve the recovery and stability of the sensing electrode. When the interlayer Cr thickness was increased from 0 to 70 nm, the resistance decreased from 27 to 8.8 kΩ. The gauge factor (GF) value also decreased from 4.24 to 2.31 with the increase in the thickness of Cr interlayer from 30 to 70 nm, and the hysteresis phenomenon disappeared gradually. The multilayer Ti/Cr/Ti film has feasible application for strain sensor.

Download Full-text

Research of a Novel 3D Printed Strain Gauge Type Force Sensor

Micromachines ◽

10.3390/mi10010020 ◽

2018 ◽

Vol 10 (1) ◽

pp. 20 ◽

Cited By ~ 6

Author(s):

Mingjie Liu ◽

Qi Zhang ◽

Yiwei Shao ◽

Chuanqi Liu ◽

Yulong Zhao

Keyword(s):

Strain Gauge ◽

Force Sensor ◽

Gauge Factor ◽

Conductive Ink ◽

Time Saving ◽

Digital Light Processing ◽

Sensor Fabrication ◽

3D Printed ◽

Linearity Error ◽

The Relationship

A 3D printed force sensor with a composite structure developed by combining digital light processing (DLP) based printing and inkjet printing technologies is described in this paper. The sensor has cost effectiveness and time-saving advantages compared to the traditional sensor manufacturing process. During this work, the substrate of the force sensor was printed by a DLP based 3D printer using a transparent high-temperature resin, and the strain gauge of the force sensor was inkjet printed using poly(3,4-ethylenedioxythiophene) polystyrene sulfonate (PEDOT/PSS) conductive ink. Finite element (FE) simulation was conducted to find the print origin of the strain gauge. The relationship between the mechanical properties of the post-cured resin and the curing time was investigated and the resistance of the printed strain gauges was characterized to optimize process parameters. Afterward, the force sensor was characterized. Experimental results show that the sensitivity of the sensor is 2.92% N−1 and the linearity error is 3.1485% full scale (FS) within the range from 0 mN–160 mN, and the effective gauge factor of the strain gauge is about 0.98. The resistance drifting is less than 0.004 kΩ within an hour. These figures prove that the device can perform as a force sensor and 3D printing technology may have great applied potential in sensor fabrication.

Download Full-text

Piezoresistive Multi-Walled Carbon Nanotube/Epoxy Strain Sensor with Pattern Design

Materials ◽

10.3390/ma12233962 ◽

2019 ◽

Vol 12 (23) ◽

pp. 3962 ◽

Cited By ~ 1

Author(s):

Mun-Young Hwang ◽

Dae-Hyun Han ◽

Lae-Hyong Kang

Keyword(s):

Carbon Nanotube ◽

Strain Gauge ◽

Low Cost ◽

Strain Sensor ◽

High Sensitivity ◽

Strain Sensors ◽

Gauge Factor ◽

Patch Type ◽

Multi Walled Carbon Nanotube ◽

Free Vibration Frequency

Carbon nanotube/polymer-based composites have led to studies that enable the realization of low-cost, high-sensitivity piezoresistive strain sensors. This study investigated the characteristics of piezoresistive multi-walled carbon nanotube (MWCNT)/epoxy composite strain sensors subjected to tensile and compressive loads in one direction at relatively small amounts of strain. A patterned sensor was designed to overcome the disadvantage of the load direction sensitivity differences in the existing sensors. The dispersion state of the MWCNTs in the epoxy polymer matrix with the proposed dispersion process was verified by scanning electron microscopy. An MWCNT/epoxy patterned strain sensor and a patch-type strain sensor were directly attached to an acrylic cantilever beam on the opposite side of a commercial metallic strain gauge. The proposed patterned sensor had gauge factors of 2.52 in the tension direction and 2.47 in the compression direction. The measured gauge factor difference for the patterned sensor was less than that for the conventional patch-type sensor. Moreover, the free-vibration frequency response characteristics were compared with those of metal strain gauges to verify the proposed patch-type sensor. The designed drive circuit compensated for the disadvantages due to the high drive voltage, and it was confirmed that the proposed sensor had higher sensitivity than the metallic strain gauge. In addition, the hysteresis of the temperature characteristics of the proposed sensor is presented to show its temperature range. It was verified that the patterned sensor developed through various studies could be applied as a strain sensor for structural health monitoring.

Download Full-text

On the relationship between decisions in one-shot and repeated tasks: experimental results and the possibility of general models

PsycEXTRA Dataset ◽

10.1037/e683322011-004 ◽

2000 ◽

Author(s):

Ido Erev ◽

Greg Barron

Keyword(s):

Experimental Results ◽

The Relationship

Download Full-text

Metal Strain Gauge Pressure Sensor Using SiO2/Si3N4 Diaphragm

IEEJ Transactions on Sensors and Micromachines ◽

10.1541/ieejsmas.139.63 ◽

2019 ◽

Vol 139 (4) ◽

pp. 63-68

Author(s):

Hiroshi Nakano ◽

Masahiro Matsumoto ◽

Yasuo Onose ◽

Kazuhiro Ohta

Keyword(s):

Pressure Sensor ◽

Strain Gauge ◽

Gauge Pressure ◽

Metal Strain

Download Full-text

Parasites and promiscuity: Acute disease salience leads to more restricted sexual attitudes

Journal of Social and Personal Relationships ◽

10.1177/02654075211030999 ◽

2021 ◽

pp. 026540752110309

Author(s):

James B. Moran ◽

Nicholas Kerry ◽

Jin X. Goh ◽

Damian R. Murray

Keyword(s):

Social Behavior ◽

Sexual Attitudes ◽

Experimental Manipulation ◽

Sexual Relationships ◽

Experimental Results ◽

Acute Disease ◽

Short Term ◽

Attitudes And Behaviors ◽

The Relationship ◽

Sexual Promiscuity

How does disease threat influence sexual attitudes and behaviors? Although research on the influence of disease threat on social behavior has grown considerably, the relationship between perceived disease threat and sexual attitudes remains unclear. The current preregistered study (analyzed N = 510), investigated how experimental reminders of disease threat influence attitudes and anticipated future behaviors pertaining to short-term sexual relationships, using an ecologically valid disease prime. The central preregistered prediction was that experimental manipulation of disease threat would lead to less favorable attitudes and inclinations toward sexual promiscuity. Results were consistent with this preregistered prediction, relative to both a neutral control condition and a non-disease threat condition. These experimental results were buttressed by the finding that dispositional variation in worry about disease threat predicted less favorable attitudes and inclinations toward short-term sexual relationships. This study represents the first preregistered investigation of the implications of acute disease threat for sexual attitudes.

Download Full-text

Piezoresistive Characteristics of Nanocarbon Composite Strain Sensor by Its Longitudinal Pattern Design

Applied Sciences ◽

10.3390/app11135760 ◽

2021 ◽

Vol 11 (13) ◽

pp. 5760

Author(s):

Sung-Yong Kim ◽

Baek-Gyu Choi ◽

Gwang-Won Oh ◽

Chan-Jung Kim ◽

Young-Seok Jung ◽

...

Keyword(s):

Axial Load ◽

Filler Content ◽

Factor Model ◽

Strain Sensor ◽

Gauge Factor ◽

Geometric Pattern ◽

Pattern Design ◽

Macro Scale ◽

Composite Strain ◽

Longitudinal Pattern

For an engineering feasibility study, we studied a simple design to improve NCSS (nanocarbon composite strain sensor) sensitivity by using its geometric pattern at a macro scale. We fabricated bulk- and grid-type sensors with different filler content weights (wt.%) and different sensor lengths and investigated their sensitivity characteristics. We also proposed a unit gauge factor model of NCSS to find a correlation between sensor length and its sensitivity. NCSS sensitivity was improved proportional to its length incremental ratio and we were able to achieve better linear and consistent data from the grid type than the bulk type one. We conclude that the longer sensor length results in a larger change of resistance due to its piezoresistive unit summation and that sensor geometric pattern design is one of the important issues for axial load and deformation measurement.

Download Full-text

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.

Download Full-text

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.

Download Full-text

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.

Download Full-text