A 4 DOF Robot for Post-Stroke Trunk Rehabilitation

The human core plays a key role in maintaining stability and allowing safe execution of movements. Stability of the core depends on the strength and control of its muscles. Hemiparesis due to stroke can compromise this control, thus reducing core stability of stroke survivors. Therefore, to allow stroke survivors to safely and independently perform activities of daily living, rehabilitation therapists focus on increasing their core stability. Core rehabilitation involves performing training exercises while sitting on stable or unstable surfaces. This paper presents the development and initial testing of a system that can provide both stable and controlled unstable surfaces for the performance of trunk rehabilitation exercises. It is a 4 DOF system that can gauge the position of the user's center of pressure (COP) using built-in instrumentation and can move according its movements. The system has a graphical interface that is used to provide movement targets to the user which they have to achieve by moving their COP. To judge the system's capability of generating an unstable exercise surface, the COP movement tracking performance of the system has been tested. Further evaluations with healthy and stroke subjects are required to elucidate the system's potential as a trunk rehabilitation tool.