Design and Analysis of a Lower Limb Exo-Skeleton Suit for Post Stroke Patient: Static and Ergonomic Analyses

Abstract

This paper presents a study on the development of a lower limb exoskeleton suit (exo-suit) for post-stroke patients. The exo-suit is designed and developed for restoration of post-stroke patients' gait motion (ability to use their lower limb joints) and analysis on ergonomics and statics are also considered. The mechanical structure of the exo-suit is proposed according to the anatomy of Asian people with an average mass of eighty kilograms in order that it is fitted perfectly. The conceptual design is established and selected by a dedicated design matrix and compared using the matrix evaluation process, and then Computer-Aided Design (CAD) software CATIA is used to create the 3D model. The design has undergone an evaluation of static structural and ergonomic analysis via CATIA and ANSYS Finite Element Analysis (FEA) software. Two materials are used in the static structural analysis, one is aluminium alloy, the other is steel material. The result of equivalent stress for both materials is within the allowable range of 29.511MPa to 1168.4 MPa. For RULA (Rapid Upper Limb Assessment) Analysis, the results showed that all three postures (static, intermittent, and repeated) yield acceptable final score which is 1 for intermittent and 2 for static and repeated postures.