Self-Sensing SMA-Textile Composite Actuator for Multi-Mode Actuation

In this study, a self-sensing soft actuator was developed by integrating shape memory alloy (SMA) wires and conductive fabric into a PDMS matrix, enabling simultaneous actuation and sensing. Bending, twisting and combined deformation modes were achieved by varying the SMA wire arrangement and the fabric sensor pattern, and the corresponding resistance changes are quantitatively characterized. The results demonstrate a consistent correlation between resistance change and both bending curvature and twist angle, with stable response characteristics maintained under repeated actuating conditions. Sensor performance was further evaluated based on response time, gauge factor, and hysteresis. Moreover, the proposed actuator was applied as a soft gripper and gripping experiments on various objects were conducted and it was confirmed that real-time resistance change can be detected concurrently with actuation. This study provides a technical foundation for soft robotic and smart material applications requiring deformation detection and real-time feedback control.