A Compact Ankle Exoskeleton With a Multiaxis Parallel Linkage Mechanism

This article proposes a compact ankle exoskeleton with a multiaxis parallel linkage mechanism. By applying torques to the ankle joint, it can generate dorsi- and plantar-flexion motions. The design variables of the mechanism were analyzed and optimized to accommodate up to 12 N·m of torque within a thickness constraint of 40 mm. The parallel linkage structure of the proposed mechanism requires that moving mechanical parts must be thin and located at the front of the shank. Using the data from foot pressure sensors, the device can recognize the gait phases. The output torque and angle data were collected to evaluate the performance of the device.