Save for infants, I’d venture to guess that 99.9 percent of the population uses their feet to walk somewhere every day. We’ve gotten so used to walking that we’ve become incredibly efficient at walking, even on uneven surfaces.
That said, even efficient load-bearing takes a toll on your feet. If you work on your feet all day, you’ve probably come home from a long day and noticed that your dogs were barking, so to speak. Because of the stress our feet take every day, researchers have long sought to develop a tool that can alleviate some of the regular load-bearing. Unfortunately, this task has proved exceptionally difficult, but a breakthrough may be on the horizon.
According to researchers at Carnegie Mellon University and North Carolina State University, they’ve developed an unpowered ankle exoskeleton that reduces the metabolic cost of walking by about 7 percent. That may sound small, but for heavier individuals and elderly people who have a tough time walking longer distances, that 7 percent decrease can make a huge difference.
Researchers say the reduced metabolic cost is the equivalent of taking off a 10-pound backpack.
“It’s a real exciting milestone for the field of assistive devices,” said Thomas Roberts, a professor of ecology and evolutionary biology at Brown University who was not involved in the study. “They’ve taken an assistive device and lowered the cost of human walking. That’s kind of a big deal because walking is already really cheap, and they did it with a very simple, but clever device.”
Although we don’t have the rights to publish a picture of the device on our blog, you can see a five-picture gallery of the walking aid here.
The device is the end result of eight years of hard work by Steve Collins and Greg Sawicki, who began researching the instrument while they were graduate students at the University of Michigan in 2007.
“Walking is more complicated than you might think,” said Collins, an assistant professor of mechanical engineering at Carnegie Mellon. “Everyone knows how to walk, but you don’t actually know how you walk.”
How it Works
Using ultrasound technology, experts found that the calf exerts energy while propelling the body forward and while holding the Achilles tendon taut. The researchers succeeded where others failed by carefully studying the biomechanics of human walking and using the information to design an ultra-lightweight device that relieves some of the excess stress on a person’s calf.
“Studies show that the calf muscles are primarily producing force isometrically, without doing any work, during the stance phase of walking, but still using substantial metabolic energy,” Collins explained. “This is the opposite of regenerative braking. It’s as if every time you push on the brake pedal in your car, you burn a little bit of gas.”
Keeping that idea in mind, researchers created an ankle exoskeleton that relieves some of the forces while the Achilles is being held taut by the calf. Collins said he believes the device has the ability to help people in all walks of life, no pun intended.
“As we understand human biomechanics better, we’ve begun to see wearable robotic devices that can restore or enhance human motor performance. This bodes well for a future with devices that are lightweight, energy-efficient, and relatively inexpensive, yet enhance human mobility,” said Collins. “You can imagine these lightweight efficient devices being worn on the affected limb to help people with the permanent aftereffects of stroke. We’re hopeful that designs that use similar techniques can help people who have had a stroke walk more easily. We’re still a little ways away from doing that, but we certainly plan to try.”
Related source: Kansas City Infozine
