A Robotic Device for Hand Motor Therapy after Stroke

Abstract

This paper describes the design of a robotic device - the hand-wrist assisting robotic device, or HWARD ("Howard") - that can assist functional grasping and releasing movements of the stroke-impaired hand. The 3 degrees-of-freedom device is pneumatically-actuated and backdriveable. The design of HWARD was guided by neurobiological principles of motor learning, such as sensorimotor integration, movement repetition, environmental complexity, and attention. Specifically, HWARD can assist repetitive grasping and releasing movements while allowing the subject to feel real objects during therapy. The use of real objects having rich sensory and functional characteristics can stimulate sensorimotor cortex activation while enhancing subject motivation and attention - features hypothesized to reduce impairment and disability. A pilot study tests the safety and efficacy of HWARD, with endpoints that include established motor function scales as well as brain mapping with functional MRI (fMRI).