Artificial ankle prosthesis is attached to end of artificial lower leg and has automatic hydraulic cylinder system which enables prosthesis to mimic flexing action of real ankle and foot joints

摘要

When the user 'rocks back on his heel', the switch (19) operates the valve (17) allowing the hydraulic piston to push the toe end away from the heel end. Later in the step, when the toe end touches the ground, the heel end operates the switch, shutting off the valve, and driving the heel and toe ends back towards each other.