A low cost tele-rehabilitation device for training of wrist and finger functions after stroke

There is a need for robotic rehabilitation devices that increase the outcome while reducing the cost of therapy. This paper presents a device for training of supination / pronation, dorsal wrist extension and finger manipulation after stroke. The system exhibits modularity in terms of the communication architecture and different optional components. User interfaces (UI) can be implemented on different kinds of devices including a Rasperry Pi single-board computer on which a Qt-based graphical UI was run. Telerehabilitation functionality is included using SSL-encrypted RESTful web services on a three-tier architecture. Expensive sensors were omitted in order to have a cost-effective system which is a requirement for home-based rehabilitation. The torque sensing is based on current measurements being evaluated by comparing it to force-torque sensor values. After canceling out the static friction, the low error justified the omission of an additional sensor.