Wearable Flexible Strain Sensor Based on Three-Dimensional Wavy Laser-Induced Graphene and Silicone Rubber
Lixiong Huang,
Han Wang,
Peixuan Wu,
Weimin Huang,
Wei Gao,
Feiyu Fang,
Nian Cai,
Rouxi Chen,
Ziming Zhu
Affiliations
Lixiong Huang
State Key Laboratory of Precision Electronic Manufacturing Technology and Equipment (2019DG780017), Guangdong Provincial Key Laboratory of Micro-Nano Manufacturing Technology and Equipment, Ultra-Precision Manufacturing Equipment Guangdong-Hong Kong Joint Laboratory, Key Laboratory of Precision Electronic Manufacturing Equipment and Technology, Ministry of Education, School of Mechanical and Electrical Engineering, Guangdong University of Technology, Guangzhou 510006, China
Han Wang
State Key Laboratory of Precision Electronic Manufacturing Technology and Equipment (2019DG780017), Guangdong Provincial Key Laboratory of Micro-Nano Manufacturing Technology and Equipment, Ultra-Precision Manufacturing Equipment Guangdong-Hong Kong Joint Laboratory, Key Laboratory of Precision Electronic Manufacturing Equipment and Technology, Ministry of Education, School of Mechanical and Electrical Engineering, Guangdong University of Technology, Guangzhou 510006, China
Peixuan Wu
State Key Laboratory of Precision Electronic Manufacturing Technology and Equipment (2019DG780017), Guangdong Provincial Key Laboratory of Micro-Nano Manufacturing Technology and Equipment, Ultra-Precision Manufacturing Equipment Guangdong-Hong Kong Joint Laboratory, Key Laboratory of Precision Electronic Manufacturing Equipment and Technology, Ministry of Education, School of Mechanical and Electrical Engineering, Guangdong University of Technology, Guangzhou 510006, China
Weimin Huang
School of Mechanical and Aerospace Engineering, Nanyang Technological University, 50 Nanyang Avenue, Singapore 639798, Singapore
Wei Gao
Department of Chemical and Materials Engineering, the University of Auckland, Private Bag 92019, Auckland 1142, New Zealand
Feiyu Fang
State Key Laboratory of Precision Electronic Manufacturing Technology and Equipment (2019DG780017), Guangdong Provincial Key Laboratory of Micro-Nano Manufacturing Technology and Equipment, Ultra-Precision Manufacturing Equipment Guangdong-Hong Kong Joint Laboratory, Key Laboratory of Precision Electronic Manufacturing Equipment and Technology, Ministry of Education, School of Mechanical and Electrical Engineering, Guangdong University of Technology, Guangzhou 510006, China
Nian Cai
School of Information Science, Guangdong University of Technology, Guangzhou 510006, China
Rouxi Chen
Department of Materials Science and Engineering, Southern University of Science and Technology, Shenzhen 518055, China
Ziming Zhu
Foshan Lepton Precision M&C Tech Co., Ltd., Foshan 528225, China
Laser-induced graphene (LIG) has the advantages of one-step fabrication, prominent mechanical performance, as well as high conductivity; it acts as the ideal material to fabricate flexible strain sensors. In this study, a wearable flexible strain sensor consisting of three-dimensional (3D) wavy LIG and silicone rubber was reported. With a laser to scan on a polyimide film, 3D wavy LIG could be synthesized on the wavy surface of a mold. The wavy-LIG strain sensor was developed by transferring LIG to silicone rubber substrate and then packaging. For stress concentration, the ultimate strain primarily took place in the troughs of wavy LIG, resulting in higher sensitivity and less damage to LIG during stretching. As a result, the wavy-LIG strain sensor achieved high sensitivity (gauge factor was 37.8 in a range from 0% to 31.8%, better than the planar-LIG sensor), low hysteresis (1.39%) and wide working range (from 0% to 47.7%). The wavy-LIG strain sensor had a stable and rapid dynamic response; its reversibility and repeatability were demonstrated. After 5000 cycles, the signal peak varied by only 2.32%, demonstrating the long-term durability. Besides, its applications in detecting facial skin expansion, muscle movement, and joint movement, were discussed. It is considered a simple, efficient, and low-cost method to fabricate a flexible strain sensor with high sensitivity and structural robustness. Furthermore, the wavy-LIG strain senor can be developed into wearable sensing devices for virtual/augmented reality or electronic skin.