Stanford University mechanical engineers report that they have developed a more stable prosthetic leg – and a better way of designing them – that could make challenging terrain more manageable for people who have lost a lower leg.

The new design features a kind of tripod foot that responds to rough terrain by actively shifting pressure between three different contact points.

Graduate student Vincent Chiu, postdoctoral researcher Alexandra Voloshina and Collins describe the construction and first tests of their prosthetic emulator in IEEE Transactions on Biomedical Engineering.

Rather than building a prosthetic limb someone could test in the real world, the team instead built a basic tripod foot, then hooked it up to powerful off-board motors and computer systems that control how the foot responds as a user moves over all kinds of terrain, they note in a media release from Stanford University.

In doing so, the team aimed to put their design focus on how the prosthesis should function – how hard one toe should push off while walking, how springy the heel should be and so forth – without having to worry about how to make the device lightweight and inexpensive at the same time.

So far the team has reported results from work with one participant, a 60-year-old man who lost his leg below the knee due to diabetes, and the early results are promising.

“One of the things we’re excited to do is translate what we find in the lab into lightweight and low power and therefore inexpensive devices that can be tested outside the lab,” says Steven Collins, an associate professor of mechanical engineering and a member of Stanford Bio-X, in the release.

“And if that goes well, we’d like to help make this a product that people can use in everyday life.”

[Source(s): Stanford University, EurekAlert]