Flexible Stretchable Strain Sensor Based on LIG/PDMS for Real-Time Health Monitoring of Test Pilots
Abstract
:1. Introduction
- By integrating laser direct writing technology and the transfer method, high-performance LIG was successfully fabricated on PI and subsequently transferred to a PDMS substrate, creating an LIG/PDMS flexible strain sensor with excellent tensile properties and sensitivity. This sensor demonstrates a maximum tensile strain of approximately 40% and a gauge factor of 20.7 within a 21% strain range.
- The LIG/PDMS-based flexible strain sensor exhibits outstanding sensing characteristics, including superior electrical conductivity (48 Ω), a low detection limit (0.1%), rapid response and recovery times (150 ms/200 ms), and excellent durability after undergoing more than 1000 stretching cycles.
- This LIG/PDMS-based flexible strain sensor was innovatively applied for the first time in the real-time monitoring of civil aviation test pilots, capturing physiological signals including blinking, pulse, finger bending, and wrist movement. This application provides a novel, efficient, and comfortable approach for real-time pilot monitoring.
2. Materials and Methods
2.1. Preparation of LIG Strain Sensor
2.2. Materials Characterization
3. Results and Discussion
3.1. Performance Testing of Flexible Sensors
3.2. Application of LIG/PDMS-Based Flexible Wearable Sensors
4. Conclusions
Author Contributions
Funding
Institutional Review Board Statement
Informed Consent Statement
Data Availability Statement
Conflicts of Interest
References
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Materials | Processing | Response Time (ms) | Gauge Factor (GF) | References |
---|---|---|---|---|
LIG-PDMS | Laser direct writing | 150 | 15.79 | [35] |
PAM-3-TSASN-LiCl hydrogel | Surface modification | 210 | 4.5 | [36] |
GAF | Graphite oxide reduction | 208 | 0.84 | [37] |
LM@CNTs-5/Fe/Ecoflex | 4D Printing | 83 | 19.8 | [38] |
B-TMN-SHFSS | \ | 230 | 0.146 | [39] |
LIG | Laser direct writing | 150 | 41.4 | [40] |
PDMS-SEBS(CB) | Spraying carbon black | 168 | 7.35 | [41] |
Gallium-based liquid metals | Extrusion thermal pressing method | 180 | 4.59 | [42] |
PDMS/CNT/FM@MX | Ultrasonically dispersed | 330 | 5.59 | [43] |
LIG-PDMS | Laser direct writing | 150 | 20.7 | This work |
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Li, S.; Wu, Z.; Fan, H.; Zhong, M.; Xing, X.; Wang, Y.; Yang, H.; Liu, Q.; Zhang, D. Flexible Stretchable Strain Sensor Based on LIG/PDMS for Real-Time Health Monitoring of Test Pilots. Sensors 2025, 25, 2884. https://doi.org/10.3390/s25092884
Li S, Wu Z, Fan H, Zhong M, Xing X, Wang Y, Yang H, Liu Q, Zhang D. Flexible Stretchable Strain Sensor Based on LIG/PDMS for Real-Time Health Monitoring of Test Pilots. Sensors. 2025; 25(9):2884. https://doi.org/10.3390/s25092884
Chicago/Turabian StyleLi, Shouqing, Zhanghui Wu, Hongyun Fan, Mian Zhong, Xiaoqing Xing, Yongzheng Wang, Huaxiao Yang, Qijian Liu, and Deyin Zhang. 2025. "Flexible Stretchable Strain Sensor Based on LIG/PDMS for Real-Time Health Monitoring of Test Pilots" Sensors 25, no. 9: 2884. https://doi.org/10.3390/s25092884
APA StyleLi, S., Wu, Z., Fan, H., Zhong, M., Xing, X., Wang, Y., Yang, H., Liu, Q., & Zhang, D. (2025). Flexible Stretchable Strain Sensor Based on LIG/PDMS for Real-Time Health Monitoring of Test Pilots. Sensors, 25(9), 2884. https://doi.org/10.3390/s25092884