Bionic Ankle Works Better Than The Real Thing
Prosthetic emulates nature to restore natural gait, balance, and speed.
Hugh Herr, an Associate Professor of Media Arts and Sciences at MIT, has been designing prosthetic legs for more than 20 years, the latest of which is a bionic ankle that outperforms conventional technology in almost every way. The customizable prosthesis not only lowers joint stress and the time it takes to acclimatize, but also restores natural gait, balance, and speed.
Battery-powered “bionic propulsion,” two microprocessors and six environmental sensors work together to adjust ankle stiffness, power, position, and damping thousands of times per second. This system operates at two key points during a person’s stride; once when the heel strikes the ground, controlling the ankle’s stiffness to absorb shock and thrust the tibia forward, and then again when power is needed to propel a wearer up and forward.
Herr, who lost both legs after a climbing accident in the 80s, explains how the difference between a conventional prosthetic, and a bionic one, is like night and day.
“It was as profound as when you’re walking through the airport and you hit the moving walkway. When you get off and return to normal walking, you’re like, ‘Walking is really strenuous and slow,’” he says. “That’s what it was like going from our powered system to passive conventional systems. So I knew there was magic there clinically.”
So far, Herr and his startup BiOM have given more than 900 patients worldwide, including some 400 war veterans, access to the bionic body part. Even though the current design has undergone more than 20 iterations, and been funded by roughly $50 million of venture capital and grants, Herr still has more in store for the world of bionic limbs.
“The bionic design approach is grounded in biological science that seeks to fundamentally understand how our bodies and brains work, and translates that knowledge into technology that reflects those principles, leading to a world where technology, because it is so innately human, essentially vanishes.”
Images: Bryce Vickmark