Optimization-based scaling procedure for the design of fully portable hand exoskeletons

In modern robotics, providing assistance to those patients who have lost or injured their hand skills, assuring them an independent and healthy life through the design of exoskeleton technologies is, surely, one of the most challenging goal. This research activity is focused on the development of a low-cost hand exoskeleton system (HES) which supports patients suffering from hand opening disabilities during the activities of daily living. The device is, then, designed to be also used during rehabilitative sessions in specific tasks to restore the dexterity of the user's hand. In this paper, the authors propose an optimization-based strategy, using a completely automatic scaling procedure, to customize hand exoskeletons for different patients. The authors have tested and validated the proposed approach by building a real HES prototype. The testing phase, conducted in collaboration with the Don Carlo Gnocchi Foundation, has showed that the optimization process leads to devices which tailor the hand of generic patients and are able to reproduce the natural kinematics of the fingers.