Preliminary Stiffness-Driven Redesign of a Laminated Prosthetic Component Using Additive Manufacturing

Area of Science:

• Materials Science and Engineering
• Biomedical Engineering
• Additive Manufacturing

Background:

• Traditional prosthetic devices are often expensive and lack personalized fit.
• Additive manufacturing (3D printing) presents an opportunity for cost-effective and customized prosthetics.
• Continuous fibre-reinforced polymers are being explored as advanced materials for structural applications.

Purpose of the Study:

• To investigate the design of an additively manufactured prosthetic foot using continuous fibre-reinforced polymers.
• To develop and validate a numerical approach for designing 3D printed composite prosthetic feet.
• To assess the feasibility of additive manufacturing as a low-cost alternative for prosthetic foot production.

Main Methods:

• A numerical design approach was developed, simulating infill structures to determine homogenized engineering constants.
• The numerical approach was validated using sandwich specimens with varying infill geometries.
• The validated approach was applied to redesign a component of a commercial foot prosthesis using additive manufacturing techniques.

Main Results:

• Numerical simulations accurately predicted stiffness within experimental standard deviation for 3D printed sandwich specimens.
• The redesigned prosthetic foot component, utilizing additive manufacturing, showed stiffness within 5% of the reference laminated component.
• The additively manufactured component was approximately 83% thicker than the reference, incorporating glass fibre skins.

Conclusions:

• Additive manufacturing with continuous fibre-reinforced polymers is a viable method for producing affordable prosthetic feet.
• The proposed numerical approach serves as an effective design tool for additively manufactured composite prosthetic devices.
• This technology offers a pathway to significantly reduce the cost of prosthetic foot manufacturing.