Development of a wearable exoskeleton for daily forearm motion assist

The paper presents a 2-d.o.f. wearable exoskeleton system designed for forearm motion assist in daily activity and rehabilitation. The proposed exoskeleton system is supposed to be directly attached to the lateral side of a patient's upper limb, and assist the forearm motion (elbow flexion-extension motion and forearm supination-pronation motion) of the patient for daily activity and rehabilitation. The proposed exoskeleton is controlled based on the activation patterns of the electromyogram signals of the patient's muscles, which directly reflect the motion intention of the patient, in order to realize natural automatic motion assist. A sophisticated real-time neuro-fuzzy control method, in which the effect of a muscle common to both motions is taken into account, is proposed. The proposed control method enables cooperative motion of the elbow and forearm of the patient by learning the muscle activation patterns of each patient. The effectiveness of the proposed exoskeleton system is evaluated by experiment.