Stiffness modulation of a cable-driven leg exoskeleton for effective human-robot interaction

With the widespread development of leg exoskeletons to provide external force-based repetitive training for gait rehabilitation, the prospect of undesired movement adaptation due to applied forces and imposed constraints require adequate investigation. A cable-driven leg exoskeleton, CDLE, presents a lightweight, flexible, and redundantly actuated architecture that enables the possibility of system parameters modulation to alter human-robot interaction while applying the desired forces. In this work, multi-joint stiffness performance of CDLE is formulated to systematically analyze human-CDLE interaction. Further, potential alterations in CDLE architecture are presented to tune human-CDLE interaction that favors the desired human leg movement during a gait rehabilitation paradigm.