Navigator: 2 Degree of Freedom Hand Rehabilitation Device

Abstract

There are no affordable hand rehabilitation devices on the market for patients who suffer from upper limb impairmnet due to stroke. The design team has succesfully developed a low cost hand rehabilitation device named the Navigator for home use that exercises finger flexion and extension (grasp and release) as well as wrist pronation and supination (rotation). Simultaneous wrist rotation and grasping motions are required for many daily tasks. A previous prototype (HERRI) exists that is capable of excercising these motions, but it is large, expensive and is intended for clinical settings. The new device is self contained, low cost, lightweight (<7 kg) and is to be used in the home. Like the HERRI, the Navigator will be connected to a computer so that users can play a game to facilitate rehabilitation and to provide users and clinicians with objective rehabilitation data. In the final design, a rack and pinion powered by a DC motor facilitates the linear flexion and extension of the fingers while a belt and pulley powered by a second DC motor facilitates the rotational pronation and supination of the wrist. An encoder, potentiometer, and torque and force sensors will be used to track user inputs and device outputs. The control system features an Arduino microcontroller that facilitates device inputs and outputs so that users can play a virtual reality game as part of therapy. æResults of controller responsiveness are presented.