Researchers at MIT have tested a new way to help people control artificial legs. It uses tiny magnets inside muscles to follow their movements. Three people took part in the study. Each person had lost a leg below the knee.
The team put pairs of magnets into muscles used to move the ankle. Each magnet was three millimetres wide. Devices on the skin measured the distance between the magnets. Changes in this distance showed the length of the muscle and how fast it moved.
The three people had earlier surgery to connect pairs of muscles again. This helps them decide how to position and move an artificial limb. Many artificial limbs use electrical signals from muscles, but sweat and signals from nearby muscles can make these less clear. The team compared the magnets with devices that measure electrical signals inside muscles and on the skin.
During the tests, people used their muscles to move a small mark on a screen, not an artificial leg. The results suggest that magnets could give more accurate and steady control. The team is now doing a larger study with artificial limbs.
