Project Overview

Most lower limb prosthetics are passive and unnatural while some are fully powered yet heavy and expensive. Many people who use lower limb prosthetics need a low-cost, low-weight option that can adapt to the user’s needs. This solution will vary heel and toe stiffness from 10-32 N/mm. It must also support at least a 1200 N load and weigh under 800 grams. Previous work in this field has yielded prosthetics that either do not provide these functions or are too heavy.

For this project we considered two potential designs, one with inline keels, and one with bent keels. The inline keel design was chosen because of its ease of manufacturability and simple hardware mounting. Once this design was chosen, G10-FR4 was selected to be our keel material because of its linear properties and it had been used by previous variations of prosthetics.

A mockup, followed by a CAD design was created using this in-line keel plan. This involved attaching the keels in a pin connection and adjusting the part design to allow for easier fabrication on a water jet. A 3 point bending test was performed to test the keel material. The flexural strength was found to be 2.5-3E6 psi for the ¼ inch thickness. This material property was then used to conduct FEA analysis of our keel design in SolidWorks. In the next semester, we plan to fabricate the current design and test its stiffness and strength at different fulcrum positions.

Team Picture

Contact Information

Team Members

• Paul Slaughter - Team Leader
• Carlos Veguilla - Communicator & BSAC
• Benjamin Halverson - BWIG
• Thomas Laidlaw - BPAG

Advisor and Client

• Prof. Darilis Suarez-Gonzalez - Advisor
• Prof. Peter Adamczyk - Client

Related Projects

• Spring 2020: Adapting a semi-active foot prosthesis to include variable heel stiffness
• Fall 2019: Adapting a semi-active foot prosthesis to include variable heel stiffness