Electrical stimulation and iterative learning control combined with real objects and simulated tasks to assist motor recovery in the upper extremity post-stroke

Abstract

Evidence supports the combination of electrical stimulation (ES) and task specific training in rehabilitation of the upper extremity following stroke. The aim of this study is to develop a rehabilitation system that delivers precisely controlled levels of stimulation to the shoulder, elbow and wrist during goal-oriented activity utilising everyday real objects. Iterative learning control (ILC) is used to update the stimulation signal applied to each muscle group based on the error between the ideal and actual movement in the previous attempt. The control system applies the minimum amount of stimulation required, maximising voluntary effort with a view to facilitating success at each given task. Markerless motion tracking is provided via a Microsoft Kinect, and a PrimeSense. Preliminary results show that ES mediated by ILC has successfully facilitated movement across the shoulder, elbow and wrist of chronic stroke patients. Overall, joint error has reduced for all participants with the mean error across all joints showing reductions for all participants. Furthermore, there was a significant reduction in extrinsic support necessary for each task. The system is described and initial intervention data are reported.