Abstract

This paper reports on a powered prosthetic knee joint powered by artificial muscles. A musculoskeletal system integrating artificial and biological muscles was simulated. The gait cycle was divided into seven modes. Based on the results of the simulation, the artificial muscles were pressurized to provide the biological knee torque. Analysis of the gait trials of an amputee showed the timing of artificial muscles was similar to EMG of biological knee muscles. This paper is an initial step forward to implement the concept of biomimetic approach in prosthetic knee technology.

Introduction

A major source of disability among the patients who have lost their limb is the lower extremity amputation, and specifically, transfemoral amputation. Approximately, 1.9 million people are affected by limb loss, and 400,000 of them have above the knee amputation [1]. Due to important role of prosthetic knee in transfemoral ambulation, its design and function are particularly important [2]. One of the deficiencies of current prosthetic knees that prevent them from achieving this control is their inability to introduce new energy into locomotion. As a result, they cannot emulate certain functionalities of biological knee in situations like level ground walking, sit to stand maneuver, and stair/slope accent [3].