Design and Control of a ۳ DOF Hand Skeleton for Rehabilitation after Stroke

Stroke is one of the most common diseases among the elderly with high personal and societal costs. In recent years, robotic rehabilitation for stroke has become an active area of research for assistance, monitoring and qualifying the rehabilitation treatments. The key issue needed for improving rehabilitation system is that patient feedback should be taken into account by the robotic rehabilitation systems for providing rehabilitation treatment. Changes in the delivery of rehabilitation treatment are an important issue since the patient or specialist should be able to express their sense about doing things and apply the needed improvements in treatment. Therefore, in this study, a three degree-of-freedom    (۳-DOF) exoskeleton design of a thumb has been investigated. Then, a control structure is provided for greater security in which the patient feedback is evaluated in order to make necessary automatic changes in method of treatment (changing speed and force). In this design, a versatile framework with high performance is offered to simultaneously control thumb force and position regarding the patients’ feedback. This may help to keep the patient in the treatment process, reduce interventions and therapist caseload, effective automatic transmission of treatment and pain relief during the course of treatment. The results of the study suggest that the force and speed on the thumb can be changed during the rehabilitation period according to the patient's needs. This advantage may be considered as an essential step for improvement of the rehabilitation efficiency.