Fabrication and Application of Silver Nanostructured Strain Sensors in Human Motion Tracking

In this study, we present the fabrication and application of silver nanowire (AgNW)-based strain sensors for human motion tracking, leveraging aerosol jet printing (AJP) to achieve the precise deposition of conductive networks.The sensors, encapsulated with Ecoflex and Silbione elastomers, exhibited a gauge factor of 45 at a strain of 20% and a maximum stretchability of 120%, balancing sensitivity and mechanical robustness.The multilayered design ensured excellent adhesion, with a peel force of 0.85 N/cm for Ecoflex and stable performance over 500 strain cycles, retaining 95% of initial adhesion strength.Motion tracking experiments demonstrated the sensors' ability to detect finger bending (resistance changes of 0.33% at 30 and 0.92% at 90), wrist pulse waves, and knee movements, with minimal hysteresis and consistent responses.The AJP process enabled uniform AgNW networks with an initial resistance of 12.5 1.2 , while the elastomer encapsulation provided conformal adhesion and environmental protection.These results highlight the potential of AgNW-based strain sensors for applications in wearable electronics, healthcare monitoring, and human-machine interfaces.Future improvements include enhancing long-term adhesion under dynamic conditions and integrating wireless communication for untethered operation, paving the way for advanced wearable systems.