FINITE ELEMENT ANALYSIS AND TOPOLOGY OPTIMIZATION OF A HIGH-PERFORMANCE LOWER PROSTHETIC LIMB

Abstract

Due to the recent development of additive manufacturing technologies, it is now possible to achieve rapid fabrication of fully functional customized products with high geometric complexity and without the constraints of traditional manufacturing techniques, such as machining. In the current paper, a lower prosthetic limb with the knee joint was designed according to the international standards and the recommendations from existing literature. Finite element analyses were performed to investigate the mechanical behavior of the prosthetic limb and detect the stress concentration regions under realistic operation conditions. For this analysis, Nickel alloy 718 was employed as a construction material. The applied loads were derived for a human body weight of 75kg after an extensive literature review. Then, design optimization was applied, employing design for additive manufacturing (DfAM) techniques in order to minimize the number of assembly parts and improve the shape of the object. Moreover, topology optimization processes were performed in order to develop a lightweight prosthetic limb and achieve a mass reduction of 67% compared to the original design. It is worth mentioning that, this remarkable weight reduction was attained without compromising the structural integrity of the part, as the factor of safety was calculated at 1.22.