A team of researchers used additive manufacturing to enhance hygiene and structural performance in a transtibial prosthetic socket by optimizing ventilation and structural integrity through topology optimization (TO) and design for additive manufacturing (DfAM). The results of the study indicated that TO significantly reduced stress concentrations, improved the strength-to-weight ratio of the socket, and the socket design provided a cost-effective, high-performance solution for improving comfort and durability.
The researchers created a digital model from image data of the residual limb of a person with an amputation, and fabricated the device using acrylonitrile butadiene styrene (ABS) material using fused deposition modeling (FDM). TO and DfAM rules were applied to achieve the multiobjective design of ventilation, weight reduction, and structural integrity by introducing geometric discontinuities.
Mechanical testing revealed a critical failure load of 918.5 N, validated by finite element analysis, which indicated peak stresses of 37.91 MPa. A 5mm thick socket with circular discontinuities demonstrated the enhanced ventilation and mechanical resilience.
The study, “Specific strength of additively manufactured below-knee prosthetic sockets with ventilation designed through topology optimization,” was published in Rapid Prototyping Journal