Comparative study of a topologically optimized lower limb prosthesis

The need for artificial limbs or prostheses has been on the rise due to army personnel being injured in recent conflicts, an increase in the numbers of senior citizens, and road accidents. Fabrication of artificial limbs is a challenge since the shape and size of each prosthesis is different, and they have complex geometries. Conventional manufacturing processes are not economical when dealing with a customizable prosthesis, so the newer technology of additive manufacturing is considered in this study. To fully exploit the advantages of this process, topology optimization was implemented on the geometry. The subject’s leg was scanned, and the obtained geometry was simplified using ANSYS’ SpaceClaim. The consequent optimization was done in solidThinking Inspire. Two case studies were considered, wherein the geometry was first optimized through conventional topology, and then the resultant geometry was further developed with a lattice. These cases were compared regarding the strength–weight ratio. Fatigue analysis was carried out for both scenarios. Also, the exoskeletal shape of the tibial region of the leg was maintained. Finally, the strength of the resultant prosthesis was validated through a compressive testing experiment.

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