Skin-Inspired Ultra-Linear Flexible Iontronic Pressure Sensors for Wearable Musculoskeletal Monitoring

• Bioinspired dual-mechanism sensor combining fabric microstructures (∝ P1/3 contact area) and ionic film (∝ P2/3 ion modulation) achieves 242 kPa−1 sensitivity with 0.997 linearity (0–1 MPa), yielding record LSF of 242,000. • Medical-grade validation via smart insole demonstrates 1.8% GRF error (vs. 6.5% in nonlinear sensors), enabling precise early fracture-risk prediction and validating medical-grade wearables. • The sensor achieves ultra-wide working range and full-range linearity, overcoming the trade-off between sensitivity and linearity in conventional flexible pressure sensors. • The biomimetic design framework provides a universal approach for developing high-performance linear sensors, with potential for broad application in wearable biomechanical monitoring.