Water‐Induced Topological Ionogels with Ultralow Hysteresis for Dynamic Plantar Pressure Sensing and Intelligent Gait Monitoring

ABSTRACT Flexible plantar pressure sensors require soft ionic materials that can withstand large deformation, suppress hysteresis, and maintain reliable signal transduction under dynamic loading, yet these properties are rarely integrated in one material platform. Here, we report a water‐induced topological ionogel (WTI) enabled by competitive hydrogen‐bond regulation in an acrylic acid/acrylamide/[BMIM]Cl/H 2 O system. Water weakens rigid polymer‐ionic liquid associations and drives the transition from aggregated polymer clusters to a dynamically adaptive topological network, thereby promoting elastic recovery and reducing energy dissipation. The optimized WTI exhibits a compressive stress of 1.02 MPa at 90% strain, a hysteresis ratio of 8.3% at 50% strain, and an ionic conductivity of about 270 mS m −1 . As a flexible pressure sensor, it delivers a response time of about 10 ms, a sensing range from 62.3 Pa to 200 kPa, and stable operation over 20,000 loading‐unloading cycles. Integrated into a wearable plantar pressure sensing system, it enables high‐resolution spatiotemporal pressure mapping and recognition of nine locomotor patterns with 99.18% accuracy through convolutional neural network analysis. This work provides a topology‐engineering strategy for low‐hysteresis ionogels for wearable biomechanical monitoring and intelligent healthcare.