Morphology Design of Soft Strain Sensors with Superior Stability for Wearable Rehabilitation Robots

Accurate human motion tracking by wearable sensors is critical for wearable robots in rehabilitation, but existing sensing technologies have several limitations, such as unaffordability, poor stability, and reliability concerns. Through the sensor morphology design, this research focuses on the development of robust soft strain sensors using crumpled single-walled carbon nanotubes (SWCNTs). Compared to planar sensors, crumpled SWCNTs sensors exhibit wide working strain ranges, robust cycling performance, and superior mechanical stability. These sensors were integrated into a rehabilitation exoskeleton and successfully monitored elbow deformation and muscle activity by sensitive, stable, and reliable signals, indicating great potential in replacing EMG and inertial sensors to provide accurate and immediate feedback for optimized operations in rehabilitation tasks. This technology provides a cost-effective, wearable, and privacy-friendly solution for motion monitoring in rehabilitation robots, improving the effectiveness and convenience of rehabilitation treatment for people with physical disabilities.