Power and Control System of Knee and Ankle Powered Above-Knee Prosthesis

Abstract

After above-knee amputation, amputees usually go under intense rehabilitation process in order to overcome their disadvantage and successfully reintegrate in the society. Passive prostheses, which are mostly used by amputees, enable performing 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 required forces. This means, that in order for the prosthesis to be able to perform high demanding power activities it must be powered, primarily in its main joints – knee and ankle. In this paper, we are presenting hydraulic power system and control system for knee and ankle powered prosthesis which we are developing in order to achieve required kinematics and dynamics of the prosthesis which would enable it to perform high power demanding activities in more natural manner, especially stair ascent.