1. Legs and Walking Laboratory of Shirley Ryan AbilityLab and the Department of Physical Medicine and Rehabilitation, Feinberg School of Medicine, Northwestern University, Chicago, IL, USA
2. Legs and Walking Laboratory of Shirley Ryan AbilityLab, Northwestern University, Chicago, IL, USA
3. Center for Robotics and Biosystems and the Department of Mechanical Engineering, McCormick School of Engineering, Northwestern University, Evanston, IL, USA
4. Center for Robotics and Biosystems, Northwestern Institute on Complex Systems, Evanston, IL, USA
5. Center for Bionic Medicine (CBM) of Shirley Ryan AbilityLab and the Department of Physical Medicine and Rehabilitation, Feinberg School of Medicine, Northwestern University, Chicago, IL, USA
6. Department of Biomedical Engineering and Department of Physical Medicine and Rehabilitation, Northwestern University, Evanston, IL, USA
7. Department of Mechanical Engineering, the Department of Biomedical Engineering, McCormick School of Engineering, and the Department of Physical Medicine and Rehabilitation, Feinberg School of Medicine, Legs and Walking Laboratory of Shirley Ryan AbilityLab, Northwestern University, Chicago, IL, USA