DISCRETE TOPOLOGY OPTIMIZATION APPLIED TO DESIGN A CONCEPTUAL MODEL FOR LOWER LIMB PROSTHESIS

Resumo

The objective of this work is to develop a methodology for a conceptual model for lower
limb prostheses using the discrete Topology Optimization (TO) techniques as a design tool. The TO
of structures is currently presented as a very promising tool for the conceptual design of structures,
structural components, and even the materials microstructure. The TO techniques allow the conception
of the structural model to be part of the optimization process, giving great freedom for the designer.
The bridging of the TO technics and the addictive manufacturing is very promising to associate the
personalized design with its manufacture. The prostheses are elements that replace partially or totally
the members and that bring an increase of the independence and functionality of the people or animals
that have incapacity or reduced mobility. In this context, the application of TO techniques allows the
creation of personalized and low cost prostheses, that, in Brasilian context, is very impor tant. The
discrete TO is based on the ground structures method that consists of the generation of truss members
connecting a mesh of nodes. The level of connectivity between the nodes can be defined by the designer.
In this work, the initial mesh is based on the 3D parameterization of ellipses defined by the geometry
of the personalized lower limb of the patient. We use the elastic topology optimization formulation
with multiple load cases and the cross-sectional areas of the members as design variables. Illustrative
examples are presented to show the potentialities the formulation.