Preparation of motion sensor using AgNWs material and performance analysis in sports activities

High-performance motion sensors are crucial for scientific training and health management. However, existing flexible strain sensors often face limitations in signal stability, response speed, and signal-to-noise ratio during dynamic monitoring, which hinders reliable high-precision data acquisition. To address these challenges, this study aimed to develop a novel strain sensor by focusing on optimizing the composite process of conductive materials and flexible substrates, thereby enhancing performance for practical human motion monitoring applications. This study fabricated a resistive flexible strain sensor using Silver Nanowires (AgNWs) as the conductive material and Polydimethylsiloxane (PDMS) as the flexible substrate. The sensor operates on the principle that strain induces changes in the conductive network's connectivity. A key innovation in fabrication lies in using dimethyl silicone oil as a pre-dispersion medium, combined with an ultrasonic-assisted process to construct a uniform and robust three-dimensional AgNWs network within the PDMS matrix, ensuring strong interfacial adhesion and structural integrity. The experimental results demonstrated superior performance of the PDMS-based sensor. Compared to sensors based on Cellulose Nanofiber (CNF) and Polyethylene Terephthalate (PET) substrates, it exhibited a resistance fluctuation of less than 5% over 3,000 tensile cycles. At 60% strain, its response time was only 5,000 ms, approximately 50% faster than that of the CNF-based sensor. Furthermore, in the 0.5-1.5 Hz frequency range typical of human motion, the sensor achieved an excellent average signal-to-noise ratio of up to 26.27 dB. This research successfully developed an AgNWs/PDMS flexible strain sensor with outstanding dynamic stability, fast response, and high signal quality, providing a reliable sensing solution for high-precision data collection in sports training and health monitoring. The main innovation points include: (1) Adopting the interface engineering strategy of dimethyl silicone oil pre dispersion to construct a uniform and stable 3D AgNWs network; (2) Integrating spin coating and screen printing to achieve integrated manufacturing of sensors; (3) Achieving breakthroughs in comprehensive performance by linking sensor design and performance, and integrating signal processing.