Designing the controlling system for LeHab passive exercise robot

Neurological patients, such a stroke or spinal cord injury, require the rehabilitation treatment in order to return back to the daily livings. To retain the musculature quantity and quality, the passive exercise can be an option which can be done by either the physical therapist or the robot assisted. LeHab robot is designed with three degree of freedoms. The robot consists of three links and three joints, as hip, knee and ankle joints. To control the system, proportional-integral-differentiation controller system is applied to the proposed study. The results of this study show that the ankle joint can move approximately 0°-50°, while the knee joint can move in range 0°-110°. The range of movement at hip joint is 0°-120°. Controlling the robot with the proposed controller indicated that there was approximately 0.5% error which compared to the target range. However, the limited range in each joint was occurred because it was limited by the structure of robot.