Fig. 2

A representative participant’s moment-angle data. As the stiffness increased (indicated by the arrow direction), the slope of the moment-angle curve increased, confirming that the prosthetic emulator is capable of creating a range of stiffness profiles. The circular arrow indicates the direction of the moment-angle curve. We also note that the moment-angle curve also shows a slight hysteresis (i.e., net negative work), effectively simulating an unpowered and elastic prosthesis