Digital Theses Archive


Tesi etd-03272023-095004

Type of thesis
Development and experimental verification of novel wearable robots for post-traumatic hand rehabilitation
Scientific disciplinary sector
Istituto di Biorobotica - PHD IN BIOROBOTICA
relatore Prof. VITIELLO, NICOLA
Tutor Dott.ssa CREA, SIMONA
  • Exoskeleton
  • robotic rehabilitation
  • traumatic-hand patient
  • kinematic compatibility
  • human-robot interaction
Exam session start date
Hand-related trauma represents one of the major causes of hospitalization. Blunt, sharp injuries, burns, and diseases such as osteoarthritis and diabetes can alter the biomechanical structure of the hand, thus impairing the overall use of the limb and the possibility to operate even simple tasks. Regardless of the causes, the clinical scenario condition that emerges after trauma is mainly characterized by joint stiffness, reduced muscle strength, and reduced joint range of motion. The treatment of the traumatic condition can be pursued either by surgical intervention or rehabilitation treatment. Given the complex scenario of intervention, surgical procedures are not always effective in restoring functionality, thus rehabilitation remains the elective solution. In this context, the scientific community has shown a rising interest in wearable robotic solutions for rehabilitation within the medical field. This paradigm can answer the need for quantitative assessment of the patient conditions, fine mobilization of the affected areas, and, ultimately, for tuning and refining the therapy along the rehabilitation path. To satisfy the clinical requirements, the developed devices should be lightweight, include all the sensors on board, and allow for a precise and reliable exchange of torque and forces at the joint level. Accordingly, the control strategies implemented should ensure safe and compliant interaction, while ensuring high performance in assisting and mobilising the targeted joint according to user intentions and necessities. The presented work aims to investigate wearable robotic solutions for the treatment of traumatic hand conditions and to conceive and validate control strategies for safe and compliant interaction with the target users during therapy. At first, the development of torque-based control strategies has been investigated on a novel Series Elastic Actuation (SEA)-based exoskeleton for the rehabilitation of the whole hand, namely HandeXos-γ. The results showed that the exploited actuation system allows the rendering of a compliant behaviour via impedance control, which can be successfully exploited in the hand rehabilitation scenario. The studied control architecture has been further embedded in a finger exoskeleton based on an innovative self-aligning kinematic chain, namely I-Phlex. Verification with healthy participants has been conducted to evaluate the overall performance in monitoring biomechanical parameters such as angle and torque at the metacarpophalangeal joint level. Results showed a root-mean-square error below 5 degrees compared to a video ground truth for the angle evaluation and a root-mean-square error below 8 mNm for the torque tracking performance. The exoskeleton has been then employed in a pilot clinical study to verify the applicability of the developed control algorithm and of an exercise pool suitable for orthopaedic rehabilitation. Results showed that the I-Phlex platform is suitable for clinical exploitation in terms of the physical human-robot interaction. The safety and reliability of the device were assessed in a single session with target patients, and the results showed an increase in the overall range of motion from 5.88% to 11% after one session of therapy. Finally, a new compact finger exoskeleton, namely H-Phlex, has been conceived and prototyped, implementing an electromyography-based control paradigm to enable a higher cognitive involvement of the user in rehabilitation exercises. Modelling and bench-top verification of this device are currently under investigation, together with the experimental verification of the high-level control strategy with human-in-the-loop tests. Overall, the results of the presented work show that the proposed wearable robotic solutions have the potential to be successfully integrated into rehabilitation treatments for patients with traumatic hands, operating in a real-time framework and ensuring safety and compliant interaction. Furthermore, the treatment with the robotic system was demonstrated to be safely and smoothly implemented in the clinical scenario, improving the repeatability of mobilization, and quantifying the clinically relevant variables. The encouraging results presented in this work suggest extending and deeply investigating the clinical use of the presented solutions for traumatic hand subjects, further improving the current designs for wider exploitation in unstructured and ecological environments.<br>