Herr heads the Biomechatronics research group at the MIT Media Lab, which is creating bionic limbs that emulate the function of natural limbs. In 2011, TIME magazine coined Herr the “Leader of the Bionic Age” because of his revolu­tionary work in the emerging field of biomechatronics–technology that marries human physiology with electro­mechanics. A double amputee himself, he is responsible for breakthrough advances in bionic limbs that provide greater mobility and new hope to those with physical disabilities. Herr’s research group has developed gait-adaptive knee pros­theses for transfemoral amputees and variable impedance ankle-foot exoskeletons for patients suffering from drop foot, a gait pathology caused by stroke, cerebral palsy, and multiple sclerosis. He has also designed his own bionic legs, and the world’s first bionic foot and calf system called the BiOM.