Real Time Control of Above-Knee Prosthesis with Powered Knee and Ankle Joints

Passive prostheses, which are mostly used by amputees, enable performance of various activities such as walking on levelled and inclined ground, and even running, riding a bicycle and as of lately swimming. However, performing high power demanding tasks, such as stair ascent, presents a problem, because the lack of muscles makes it impossible to produce the required forces. To perform high demanding power activities, prosthesis must be powered, primarily in its main joints - knee and ankle. In this paper, we present the real time control of newly developed above-knee prosthetic SmartLeg prototype with powered knee and ankle joints. Specialized control unit is developed in order to achieve required kinematics and dynamics to enable it to perform high power demanding activities in more natural manner, especially stair ascent.