Designing Custom Mechanics in Running-Specific Prosthetic Feet via Shape Optimization

Area of Science:

• Biomechanics
• Prosthetics Design
• Computational Mechanics

Background:

• Running prosthetics are specialized curved springs storing elastic energy.
• Current design methods are limited by complex geometric constraints.

Purpose of the Study:

• To introduce a shape optimization tool for designing running prosthetics with desired mechanics.
• To generate and validate new prosthetic foot shapes.

Main Methods:

• Developed two formulations for prosthetic foot mechanics.
• Utilized custom spline-based shape optimization.
• Designed and characterized three running prosthetics with varied horizontal deflections.
• Compared prosthetics' endpoint mechanics and biomechanics in an amputee athlete.

Main Results:

• Shape optimization successfully derived shapes altering prosthesis mechanics.
• Benchtop testing validated the performance of two newly designed feet.
• Subject's knee moments increased with horizontal endpoint deflection as predicted.

Conclusions:

• A validated shape optimization tool was developed for achieving desired running prosthetic mechanics.
• This framework can help researchers understand the relationship between prosthetic mechanics and athlete performance.