Variable stiffness pneumatic ankle prosthesis with self-recharging for weight-lifting exercises

This paper presents a semi-active ankle prosthesis that adapts its stiffness to accommodate different gym exercises. The prosthesis is pneumatically actuated, and features a wireless adjustment of air pressure via smartphone app as well as a self-replenishing “pumping” mode, allowing operation without a pre-charged reservoir. Preliminary validation results with one subject suggest improved loading symmetry during walking and the back squat, and a sufficient ankle torque capacity for weightlifting 45kg (100 lb).