Affiliation:
1. Department of Smart Wearables Engineering, Soongsil University, Seoul 156-743, Republic of Korea
2. Department of Materials Science and Engineering, Soongsil University, Seoul 156-743, Republic of Korea
Abstract
Flexible wearable sensors are integral in diverse applications, particularly in healthcare and human–computer interaction systems. This paper introduces a resistive stretch sensor crafted from shape memory polymers (SMP) blended with carbon nanotubes (CNTs) and coated with silver paste. Initially, the sensor’s characteristics underwent evaluation using a Universal Testing Machine (UTM) and an LCR meter. These sensors showcased exceptional sensitivity, boasting a gauge factor of up to 20 at 5% strain, making them adept at detecting subtle movements or stimuli. Subsequently, the study conducted a comparison between SMP-CNT conductors with and without the silver coating layer. The durability of the sensors was validated through 1000 cycles of stretching at 4% ∆R/R0. Lastly, the sensors were utilized for monitoring respiration and measuring human breathing. Fourier transform and power spectrum density (PSD) analysis were employed to discern frequency components. Positioned between the chest and abdominal wall for contact-based respiration monitoring, the sensors revealed a dominant frequency of approximately 0.35 Hz. Signal filtering further enhanced their ability to capture respiration signals, establishing them as valuable tools for next-generation personalized healthcare applications.
Subject
Polymers and Plastics,General Chemistry
Reference43 articles.
1. Sleep Monitoring Sensor Using Flexible Metal Strain Gauge;Kwak;Jpn. J. Appl. Phys.,2018
2. The Dual-Mode Sensing of Pressure and Temperature Based on Multilayer Structured Flexible Sensors for Intelligent Monitoring of Human Physiological Information;Zhou;Compos. Sci. Technol.,2023
3. Kim, J.-S., Truong, T., and Kim, J. (2023). Development of Embroidery-Type Sensor Capable of Detecting Respiration Using the Capacitive Method. Polymers, 15.
4. Washable Patches with Gold Nanowires/Textiles in Wearable Sensors for Health Monitoring;Zhao;ACS Appl. Mater. Interfaces,2022
5. Flexible Pressure Sensors Based on the Controlled Buckling of Doped Semiconducting Polymer Nanopillars;Tsuda;ACS Appl. Mater. Interfaces,2021