Low-Cost Prosthetic Knee Mimics Walking Motion
From: Medical Design Briefs - 08/04/2015 - page 30

Top-of-the-line prosthetics, featuring microprocessors, gyroscopes,
accelerometers, and hydraulics, can cost more than $50,000. Using only simple
mechanical elements, researchers at the Massachusetts Institute of
Technology, Cambridge, designed a lower-cost prosthetic knee that mimics
normal walking motion. The team is testing the prosthetic knee in India, an
area with approximately 230,000 aboveknee amputees.

As prostheses are generally one-third to one-half as heavy as natural legs
and feet, the researchers adjusted the device’s torque profile to apply to
lighter leg segments.

Their prototype's spring and two dampers act as brake pads. The spring allows
the knee to bend just before the foot pushes off the ground. Simultaneously,
the first damper engages to prevent the leg from swinging back. The second
damper engages as the leg swings forward, slowing it down just before the
heel strikes the ground.

Webpage:
http://www.medicaldesignbriefs.com/component/content/article/mdb/news/22695

Links:
A cheaper, high-performance prosthetic knee
http://news.mit.edu/2015/cheaper-high-performance-prosthetic-knee-0731

Low-cost prosthetic knee could let the impoverished walk normally
http://www.gizmag.com/low-cost-prosthetic-knee/38736