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Abdominal circumference changes in every respiration: (a) In inhalation, abdominal circumference is increased and it put force on the TCRS. (b) In exhalation, abdominal circumference is decreased and force of TCRS is decreased. ∆d means the distance or diameter changes of subject's body from respiratory movement. (c) The distance between plates is varied by respiration. In inhalation, outward force is generated and it makes the distance between plates shorter and the area larger.
Source publication
We propose a simplified structural textile capacitive respiration sensor (TCRS) for respiration monitoring system. The TCRS is fabricated with conductive textile and Polyester, and it has a simple layered architecture. We derive the respiration by the distance changes between two textile plates in the TCRS, which measures the force from the abdomin...
Contexts in source publication
Context 1
... does not change. The capacitive respiration sensor is displacing piezoresistive pressure sensor because of lower power requirements, less temperature, and lower drift [19]. The plate is exposed to the process pressure on one side and to a reference pressure on the other. Changes in force cause it to deflect and change the capacitance. Fig. 1(c) shows the change of the distance between plates and area caused by force from inhalation. Because inhalation generates the centrifugal force, plates are pushed and get nearer. Also, centrifugal force stretch the textile sensor, therefore the area of sensor can be varied with Young's modulus, and it makes the change of capacitance. ...
Context 2
... characteristic, abdominal and chest muscle moves by respiration mechanism. The movement of muscle makes an amount of force to the outward. Fabricated TCRS uses this principal caused by abdominal movement, which transfers the force or pressure to TCRS. This force or pressure leads to distance change between conductive textile electrodes (see Fig. 1). Finally, inhalation and exhalation could be determined by capacitance variation derived from the changes of chest and abdominal ...
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Citations
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Purpose
The aim of this review is to present together the studies on textile-based moisture sensors developed using innovative technologies in recent years.
Design/methodology/approach
The integration levels of the sensors studied with the textile materials are changing. Some research teams have used a combination of printing and textile technologies to produce sensors, while a group of researchers have used traditional technologies such as weaving and embroidery. Others have taken advantage of new technologies such as electro-spinning, polymerization and other techniques. In this way, they tried to combine the good working efficiency of the sensors and the flexibility of the textile. All these approaches are presented in this article.
Findings
The presentation of the latest technologies used to develop textile sensors together will give researchers an idea about new studies that can be done on highly sensitive and efficient textile-based moisture sensor systems.
Originality/value
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The article can be download from the link as below;
https://www.emerald.com/insight/content/doi/10.1108/IJCST-05-2021-0061/full/html
... Flexible strain sensors have recently been proposed for real-time pulse monitoring. These sensors are lightweight, simple, and easily affixed to the skin [15] . High sensitivity and adaptability are provided by patch-type sensors that use polyaniline to efficiently measure pressure changes brought on by blood flow. ...
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