Exoneuromusculoskeleton for Upper Limb Rehabilitation After Stroke

Inclusion Criteria: For the subacute groups: * Two weeks after the onset of stroke, however less than 0.5 year * Mini-Mental State Examination (MMSE)\>21 * Able to sit up for at least 1 hour * Fugl-Meyer Assessment (FMA) upper limb \<30 * Modified Ashworth Score (MAS) at the elbow, wrist and fingers \<3 * Detectable EMG on the target driving muscles (i.e., 3 times of the standard deviation above the baseline) For the chronic device assisted group: * At least 0.5 year after the onset of stroke * Mini-Mental State Examination (MMSE)\>21 * Able to sit up for at least 1 hour * Fugl-Meyer Assessment (FMA) upper limb \<30 * Modified Ashworth Score (MAS) at the elbow, wrist and fingers \<3 * Detectable EMG on the target driving muscles (i.e., 3 times of the standard deviation above the baseline) Exclusion Criteria: Subjects will be excluded if they do not meet the above inclusion criteria, or had the following conditions: * Currently pregnant * Dysphasia (language deficiency) * Post-stroke neglect * Pacemaker implantation, * Involved in drug studies, other clinical trials, or concurrent medication/occupational/physical treatments on the upper limb * The overall medical condition not suitable for the training (e.g., severe cardiac problem, unstable blood pressure, etc.).