Katy Olesnavage, a mechanical engineering doctoral student at Massachusetts Institute of Technology (MIT), is the recipient of the $15,000 Lemelson-MIT “Cure it!” Student Prize, which honors promising young inventors around the country. Olesnavage was recognized for the work she is doing to improve the Jaipur Foot. Olesnavage, who received her bachelor’s and master’s degrees in mechanical engineering in 2012 and 2014 from MIT, focused her master’s dissertation on a new design method for a low-cost, high-performance passive prosthetic foot that better replicates physiological gait kinematics, enabling people with lower-limb amputations to walk more naturally. Her dissertation work was foundational to her selection as the prize recipient.
Bahgwan Mahaveer Viklang Sahayata Samiti (BMVSS), the Jaipur, India-based organization that distributes the Jaipur Foot and other assistive devices, asked Olesnavage’s doctoral advisor to help design a new foot that could be mass produced without sacrificing performance, and she made that her doctoral project.
In working toward a solution, Olesnavage discovered that the leading design principle of roll-over shape doesn’t fully describe the gait kinematics of a prosthetic foot, so she invented a design objective called the Lower Leg Trajectory Error that looks at the positions of the knee and lower leg at each instant during a step and measures how far they depart from the ideal kinematics. A foot that minimizes that error yields the most natural gait. Thus, it is unnecessary to faithfully replicate a natural foot. What matters is the person’s lower leg, which interfaces with the foot. If the lower leg moves naturally and experiences the loads borne by an able-bodied leg, the person will walk comfortably.
The resulting foot can be made of low-cost injection-molded nylon or 3D-printed to sell for around $10 in the developing world, or it can be made from carbon fiber for markets that can bear a $1,000 price point. Once the low-cost foot is ready for production, BMVSS will replace its Jaipur Foot with Olesnavage’s design, creating instant distribution for 24,000 units annually. As BMVSS does not have the manufacturing equipment to actually produce the feet, Olesnavage is also meeting with Indian materials suppliers and manufacturers and exploring whether a business should be started to distribute the technology or if the technology should be licensed to an existing company. The higher-cost foot must meet various U.S. Food and Drug Administration and International Organization for Standardization regulations. Ultimately, Olesnavage could develop a suite of prosthetic feet optimized for uses other than level-ground walking, such as a foot that could allow squatting or a foot that could support heavy loads.
Editor’s note: This story was adapted from materials provided by the Lemelson-MIT Program.
