Robot Assisted Gait Training With Active Leg Exoskeleton (ALEX)

Gait training of stroke survivors is crucial to facilitateneuromuscular plasticity needed for improvements in functionalwalking ability. Robot assisted gait training (RAGT) was developedfor stroke survivors using active leg exoskeleton (ALEX) anda force-field controller, which uses assist-as-needed paradigm forrehabilitation. In this paradigm undesirable gait motion is resistedand assistance is provided towards desired motion. The force-field controller achieves this paradigm by effectively applying forces at the ankle of the subject through actuators on the hip and knee joints. Two stroke survivors participated in a 15-session gait training study each with ALEX. The results show that by the end of the training the gait pattern of the patients improved and became closer to a healthy subject’s gait pattern. Improvementis seen as an increase in the size of the patients’ gait pattern, increased knee and ankle joint excursions and increase in their walking speeds on the treadmill.