A Redundantly Actuated Ankle Rehabilitation Robot and Its Control Strategies

Robotic-based rehabilitation has attracted great attention since it provides various advantages from the viewpoint of patients, therapists and rehabilitation process. This paper presents a redundantly actuated ankle rehabilitation robot, its control schemes for the common rehabilitation exercises, and experimental results indicating the effectiveness of the control schemes and the performance of the controllers. In order to analyze the effect of external disturbance in position control scheme, the related experiments are performed with and without artificial disturbance required for making a fair performance comparison of the optimized controllers. The effectiveness of admittance control scheme is analyzed utilizing a healthy subject. The performance of the developed controllers are calculated using common performance indexes.