Control and Evaluation of Stair Ascent with a Powered Transfemoral Prosthesis

Abstract

This thesis describes the control and assessment of a powered transfemoral prosthesis for improving amputee stair ascent. It begins with motivation for the work and a description of current lower-limb prosthetic technology. Then it explains the finite-state-based impedance-admittance control philosophy and implementation for both the knee and the ankle joints of a powered prosthesis. Next, it presents experimental assessments and evaluates the effectiveness of the device and controller at reducing metabolic effort and improving joint biomechanics for three transfemoral amputee subjects climbing stairs. These sections finish with general conclusions regarding the biomechanical and energetic benefits of this technology.