The aim of this study was to identify the assistance effect of Ankle Assist Robot v1 developed by Samsung Advanced Institute of Technology (Samsung Electronics Co, Ltd., Korea) by comparing

1. gait function during overground gait in three conditions (with robot-assist torque on/with robot-assist torque off/without robot)
2. the energy expenditure during treadmill gait in three conditions (with robot-assist torque on/with robot-assist torque off/without robot)

Inclusion Criteria:

• Stroke patients with hemiplegia over 19 years old
• Ischemic or hemorrhagic stroke patients over 3 months of onset
• Functional Ambulation Category Scale with 3 or more scales

Exclusion Criteria:

• Stroke patients who have difficulty in walking independently regardless of assistive devices due to problems such as visual field defects or fractures
• Stroke patients with walking difficulty due to serious cognitive problems
• Patients with a foot size of 230 mm or less or a stroke of 280 mm or more that are not suitable for wearing ankle assist robot
• Stroke patients at risk of falling when walking with severe dizziness
• Modified ashworth scale (MAS) Stroke patients over 3
• Pregnant woman
• People with mental illness and psychiatric medication