Triboelectric Insoles with Normal‐Shear Plantar Stress Perception

Abstract

AbstractPlantar stress perception is highly desired in sports science and medical research, with the constraint of external power supply to impede the portability and flexibility in daily life. Triboelectric nanogenerator (TENG) opens a new avenue for self‐power sensing; however, a comprehensive sensing of normal and shear plantar stress remains elusive, let alone the further exploration from a mapping perspective. Here, a TENG‐based self‐powered sensing insole is developed for a comprehensive normal‐shear plantar stress mapping among four critical positions. At each position, four TENG units with single‐electrode‐mode triboelectrification are incorporated to decouple the normal and shear stress based on asymmetrical outputs. The insole exhibits excellent static characteristics for plantar stress measurement. Also, it can dynamically capture plantar stress variations to distinguish between different states during a standing long jump, enabling sports performance evaluation and rectification. Moreover, with the assistance of artificial intelligence in signal processing, different abnormal gaits can be precisely identified by the insole, highlighting the potential for disease diagnosis and rehabilitation. To the best of the knowledge, this work is the first demonstration of a self‐powered TENG insole with a comprehensive perception of normal and shear plantar stress perception, holding promise for applications in sports science and medical research.