Hugs Influence Exoskeleton Design


A bionic exoskeleton allows wheelchair users to stand and walk. Image: Ekso Bionics

Walking inventions to assist paraplegics, stroke victims, and others with mobility issues aren’t new, but Ekso Bionics has focused on trying to help take development to the highest level. Nathan Harding, CEO of the company, says it combined two military projects it had worked on—the ExoClimber and the Hulc (Human Universal Load Carrier). “The early units would have multiple straps on the thigh and the shank and then over the foot would have one,” he recalls. “And there were shoulder straps like a backpack and another on the patient like a cummerbund.”

Harding immediately saw that “no matter how crude” their early exoskeleton device was, the patients and doctors were extremely excited.

The prototype of the new device, dubbed Ekso, was about 85 pounds, and not weighing directly down on a patient, but to the side. Nevertheless, this still was an issue because the device needed to be balanced.

Some of the more difficult moments turned out to be the emotional ones. “For us, we’d be very nervous but the patients would be incredibly positive,” he recalls. Patients trying it out would usually come with family and the creators wanted it to have a stop button for the time being. The problem?

Matt Tilford is one of the Ambassadors for Ekso Bionics. Image: Ekso Bionics

“We didn’t perceive that families hadn’t gotten a really good hug from this person in a wheelchair in years,” he says. “The patient would stand up and the family would get so excited, and it was usually the mom who would come in for this amazing hug. And we’d have to say, ‘Don’t touch that button.”

He laughs at the memory: “I guess we needed to have the device be ready for hugs.”

Today, the device is different in terms of control and is seen by Harding as a helpful device for a rehabilitation center. “It’s adjustable, where you can go from one size patient to another in less than five minutes,” he says of the suit. Harding, who has a Master’s degree in mechanical engineering from the University of California, Berkeley, also says the firm’s software is built to help patients in early sessions, when they’re not as stable. “We can get 200 to 300 steps in the first session. That’s important for rehabilitation customers because a patient may only be reimbursed [by insurance] for 16 to 24 sessions. You want them to be able make the most of it.”

The suit’s material is now comprised of mainly aluminum components with a small amount of carbon fiber. Designers also called on an artist who utilized leather and a patient without motor control in his legs but who still had 100% sensation. He helped work on the material to avoid skin injuries. Harding says avoiding skin injuries is a top issue for those with paraplegia. The suit’s weight has now been reduced. Harding says the device weighs about 50 pounds with a battery.

Still Steps to Take

Harding believes the best is yet to come. “We’re at the very beginning of what the human exoskeleton industry can do and we’ll have people running faster, jumping higher,” he says. “It will culminate in things like a grandma showing off her ‘exopants,’ which allow her to go on a walk with her grandkids, when before, she would maybe be too tired.”

And, for Harding, he’s anything but tired when it comes to trying to further the technology. “It’s a wonderful thing to be working on this because it’s a very positive way to use technology,” he says. “But it’s also a big responsibility, too. Because we’ve got to see it through for them.”

Eric Butterman is an independent writer.

We didn’t perceive that families hadn’t gotten a really good hug from this person in a wheelchair in years.”

Nathan Harding, CEO, Ekso Bionics


April 2015

by Eric Butterman,