Design and development of 19-DOF responsive SMA-based exoskeleton for rehabilitation

This paper introduces a new 19-DOF hand rehabilitation exoskeleton that uses memory-shape alloy (SMA) actuators and an integrated feedback console for data-driven, patient-specific therapy. The slim, quick-to-respond design enables the exoskeleton to incorporate advanced rehabilitation strategies, including assistive, challenge-based, and coaching modes tailored to individual needs. It avoids compromising agility and functionality and achieves a compact form factor by substituting bulky motor actuators with SMA wires. Integrated sensing systems, coupled with feedback, enable real-time monitoring of progress, telerehabilitation, and Activities of Daily Living (ADL) exercises. Experiments carried out earlier confirmed that the device can be used without imposing any movement restrictions. This provides natural assistance while avoiding the constraints of traditional mechanical drive systems. The linkage-based transmission combined with the SMA-based strategy balances cost, complexity, and weight, making it an attractive option for autonomous hand rehabilitation focused on patients.