Design of test bench apparatus and preliminary weight reduction strategy for an active knee prosthesis

Abstract

This thesis presents the design and structural analyses of an experimental test bench for the characterization of an active biomimetic knee prosthesis currently being developed by the Biomechatronics research group at MIT Media Laboratory. Finite element analysis (FEA) is conducted to determine the maximum stress and material deflections of three principle components of the test bench and to verify their structural integrity. In addition, FEA is performed on the chassis of the active knee prosthesis when subjected to the expected loads associated with walking. The simulation results verify that the active prosthetic do not expect structural failure during level ground walking trials with above knee amputee participants. Finally, an empirical weight reduction strategy for the active knee is proposed and analyzed. This strategy aims to reduce distal leg mass which contributes to the overall energetic demands of amputee walking. FEA on the modified active knee prosthesis chassis validate the strategy modifications while maintaining the original design feature constraints.