The ankle is something of an anatomical puzzle.
"Imagine you have a collection of pebbles, and you wrap a whole bunch of elastic bands around them," Neville Hogan, a mechanical engineering professor at MIT, said in a school news report. "That's pretty much a description of what the ankle is. It's nowhere near a simple joint from a kinematics standpoint."
So Hogan teamed up with colleagues at MIT's Newman Laboratory for Biomechanics and Human Rehabilitation to test Anklebot, a robot that uses electrodes to record the torque and angular displacement at the joint and calculate stiffness in various directions.
To do this, the bot is mounted to a knee brace that is in turn connected to a custom shoe, and Anklebot… Read more