Conductive Superhydrophobic 3D Textile Sensor Based on a Layered Design for Detecting Human Motions

Lightweight, flexible, and breathable textile-based pressure sensors have attracted considerable interest in the fields of health monitoring and human–machine interaction (HMI). In this research, a multifunctional coated piezoresistive pressure sensor was constructed on a three-dimensional spacer fabric (3D SF) via a facile dip-coating process, using a self-prepared wool biochar/silver nanoparticle composite. This method created a stable conductive network on the fabric’s surface before utilizing the bridging effect of the silane coupling agent (KH570) to strengthen the interfacial bonding force between the superhydrophobic coating and the inner conductive layer. Experimental results demonstrate that the sensor exhibits high sensitivity (89.08 kPa –1 ) and fast response time (439.63 ms) within 0–11 kPa and can effectively identify electrical signals of different intensities from subtle muscle contractions to significant joint bending. After 1000 compression cycles, the sensor still maintains good stability. Furthermore, the addition of the outer graphene-PDMS (G-PDMS) coating endows the fabric with remarkable self-cleaning properties and superhydrophobicity, with a water contact angle of 153°. This hierarchical coating sensing strategy significantly improves the anti-interference ability of the sensor in humid environments while maintaining good response sensitivity, showing promising application potential in the field of human monitoring and HMI.