Multi-channel wearable fiber sensors with high sensitivity for limb motion recognition†

A versatile multi-channel wearable flexible fiber sensing system is designed for detecting limb motion and recognizing gait patterns. Superelastic porous polyurethane (PU) fibers, featuring controllable morphology and function, were crafted using a coaxial co-injection capillary microfluidic device. These PU fibers can be stretched up to 600% elongation while maintaining stable performance. The simple and controllable fabrication of fiber sensors via microfluidic methods, although rarely reported, ensures uniform dispersion of nanostructures, such as polydopamine nano structural particles (PDA NSPs), within the flexible fibers. The incorporation of PDA NSPs enhances the conductivity and sensitivity of the PU fibers, tailored for detecting limb motion and recognizing gait patterns. An advanced wearable intelligent health monitoring system featuring multi-channel detection was engineered using flexible fiber sensors, capable of detecting a range of limb movements, including finger, wrist, elbow, and knee bending, and accurately identifying gait patterns in under 1 second response time. The findings of this research exhibit promising avenues for development and application in areas such as neuromuscular disorders, movement disorders, and assisted rehabilitation training.