Hugh M. Herr

TL;DR: The history and state of the art of lower limb exoskeletons and active orthoses are reviewed and a design overview of hardware, actuation, sensory, and control systems for most of the devices that have been described in the literature are provided.

TL;DR: The results indicate that a variable-impedance orthosis may have certain clinical benefits for the treatment of drop-foot gait compared to conventional ankle-foot orthoses having zero or constant stiffness joint behaviors.

TL;DR: A model of human locomotion is developed that is controlled by muscle reflexes which encode principles of legged mechanics and is found to stabilize into a walking gait from its dynamic interplay with the ground, reproduce human walking dynamics and leg kinematics, tolerate ground disturbances, and adapt to slopes without parameter interventions.

TL;DR: A myoelectric-driven, finite state controller for a powered ankle-foot prosthesis that modulates both impedance and power output during stance is developed and evaluated, finding that the amputee can robustly transition between the finite state controllers through direct muscle activation, allowing rapid transitioning from level-ground to stair walking patterns.

TL;DR: It is found that the powered prosthesis decreases the amputee's metabolic COT on average by 14% compared to the conventional passive-elastic prostheses evaluated (Flex-Foot Ceterusreg and Freedom Innovations Sierra), even though the powered system is over twofold heavier than the conventional devices.