Digital Design Workflow for Individualized 2-DOF Ankle Exoskeletons

Gait rehabilitation programs aid individuals recovering from brain injury or severe lower-leg trauma. While robotic exoskeletons may offer advantages over traditional exercise-based interventions, their high cost and lack of personalized fit limit their clinical utility. In this paper, we present a new efficient design workflow for individualized 2-DOF ankle exoskeletons. The anatomical orientations of the talocrural and subtalar joints are estimated by utilizing a functional calibration procedure and then embedded and implemented into the ankle exoskeleton. The exoskeleton is fabricated using affordable additive manufacturing processes to conform to the user's leg morphology. This creates a personalized design that encapsulates the envelope of the ankle joint complex motion. By achieving this without the need for kinematic redundancy, we aim at maintaining a lightweight design with reduced mechanical complexity. Early tests with two healthy individuals indicate the feasibility of the proposed approach.