A bioinspired fish scale-based flexible strain sensor for human motion signal detection

Flexible sensing devices hold extensive application prospects in fields such as bioelectronics, healthcare, intelligent sensing, and robotic electronic skin (e-skin). However, achieving stable signal transmission in humid environments, particularly underwater, remains a significant challenge. To address this issue, this study draws inspiration from the super-lubricating structure of fish scales to design a biomimetic, superhydrophobic flexible sensor (S-GCS). By combining spray coating and templating methods, a fish scale-like micro-nano structure was constructed on the surface of silicone rubber. Benefiting from its superhydrophobic properties, the S-GCS maintains excellent hydrophobicity even after prolonged exposure to underwater environments, with a contact angle exceeding 150° even after immersion in acidic or alkaline solutions. Furthermore, the robust micro-nano structure on its surface ensures that the sensor retains a high contact angle and stable signal transmission performance after 40 cycles of sandpaper abrasion and tape peeling tests, as well as during 1000 bending cycles, providing reliable assurance for its practical applications. The S-GCS not only effectively detects human motion signals but also adapts to the signal transmission requirements of underwater environments, offering innovative insights and feasible solutions for the development of future underwater flexible sensors.