Skin-inspired, permeable, structure-gradient fiber mats for pressure sensing in rehabilitation assistance

Abstract

Rehabilitation devices that integrate pressure sensors can measure vital metrics such as muscle activities and body posture, allowing patients to perform rehabilitation exercises independently without the need for constant professional oversight. However, traditional devices are commonly constructed based on thin-film plastics and rely on external power sources that are housed in bulky encapsulation cases, compromising user inconvenience and discomfort when worn for rehabilitation activities. While textile-based sensors with self-powering capabilities offer comfort and mobility without external power sources, their sensitivity and sensing range for pressure changes fall short compared to those counterparts. To address this challenge, we herein introduce a skin-inspired, permeable, structure-gradient fiber mat (SGFM) for triboelectric pressure-sensing textiles. Permeable SGFM, created through template-assisted layer-by-layer electrospinning, mimics human skin's rigidity-to-softness mechanical transition. Such a structural design can effectively enhance the dielectric and compressive properties of SGFM, thereby significantly enhancing the sensitivity of the SGFM-based triboelectric pressure sensing textiles over a broad sensing range (0.068 kPa−1 in 0–53 kPa, 0.013 kPa−1 in 53–660 kPa). Notably, the electrospun fibrous structure of SGFM provides pressure sensing textiles with promising moisture permeability, ensuring a comfortable wearing experience. As a proof-of-concept demonstration of applications, SGFM was incorporated into a wearable rehabilitation monitoring system to detect quadriceps, pulse, and plantar pressures for posture tracking and correction, displaying substantial potential for enhancing the efficiency of rehabilitation assistance.