Design of low-cost, fully passive prosthetic knee for persons with transfemoral amputation in India

Abstract

Thesis: S.M., Massachusetts Institute of Technology, Department of Mechanical Engineering, 2015.Cataloged from PDF version of thesis.Includes bibliographical references (pages 51-54).An estimated 230,000 above-knee amputees are in need of prosthetic devices in India with a majority of them facing severe socio-economic constraints in their daily lives. However, only a few passive prosthetic knee devices in the market have been designed to enable normative gait and to meet the unique daily life needs of above-knee amputees in the developing world. This thesis builds upon a past study at MIT, which established optimal mechanical component coefficients in prosthetic knee function required for achieving able-bodied kinematics. A mechanism for the design of a fully passive, low-cost prosthetic knee device, which aims to facilitate able-bodied kinematics at a low metabolic cost is presented. The mechanism is implemented using an automatic early stance lock for stability, a linear spring for early stance flexionextension and a differential friction damping system for late stance and swing control. For preliminary validation of the knee mechanism two field trials were carried out on five above-knee amputees in India, which showed satisfactory performance of the early stance lock and enabled smooth stance to swing transition by timely initiation of late stance flexion.by Venkata Narayana Murthy, Arelekatti.S.M