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Caltech’s Brain-Controlled Exoskeleton Will Help Paraplegics Walk

The exoskeleton’s neural connections will enable people with spinal cord injuries to balance and walk without crutches

3 min read
Caltech lower-body exoskeleton

This lower-body exoskeleton, developed by Wandercraft, will allow disabled users to walk more dynamically.

Caltech

Bipedal robots have long struggled to walk as humans do—balancing on two legs and moving with that almost-but-not-quite falling forward motion that most of us have mastered by the time we're a year or two old. It's taken decades of work, but robots are starting to get comfortable with walking, putting them in a position to help people in need.

Roboticists at the California Institute of Technology have launched an initiative called RoAMS (Robotic Assisted Mobility Science), which uses the latest research in robotic walking to create a new kind of medical exoskeleton. With the ability to move dynamically, using neurocontrol interfaces, these exoskeletons will allow users to balance and walk without the crutches that are necessary with existing medical exoskeletons. This might not seem like much, but consider how often you find yourself standing up and using your hands at the same time.

“The only way we're going to get exoskeletons into the real world helping people do everyday tasks is through dynamic locomotion," explains Aaron Ames, a professor of civil and mechanical engineering at Caltech and colead of the RoAMS initiative. “We're imagining deploying these exoskeletons in the home, where a user might want to do things like make a sandwich and bring it to the couch. And on the clinical side, there are a lot of medical benefits to standing upright and walking."

The Caltech researchers say their exoskeleton is ready for a major test: They plan to demonstrate dynamic walking through neurocontrol this year.

Getting a bipedal exoskeleton to work so closely with a human is a real challenge. Ames explains that researchers have a deep and detailed understanding of how their robotic creations operate, but biological systems still present many unknowns. “So how do we get a human to successfully interface with these devices?" he asks.

There are other challenges as well. Ashraf S. Gorgey, an associate professor of physical medicine and rehabilitation at Virginia Commonwealth University, in Richmond, who has researched exoskeletons, says factors such as cost, durability, versatility, and even patients' desire to use the device are just as important as the technology itself. But he adds that as a research system, Caltech's approach appears promising: “Coming up with an exoskeleton that can provide balance to patients, I think that's huge."

The lower-body exoskeleton developed by Wandercraft.

imgCaltech researchers prepare for a walking demonstration with the exoskeleton.Photo: Caltech

One of Ames's colleagues at Caltech, Joel Burdick, is developing a spinal stimulator that can potentially help bypass spinal injuries, providing an artificial connection between leg muscles and the brain. The RoAMS initiative will attempt to use this technology to exploit the user's own nerves and muscles to assist with movement and control of the exoskeleton—even for patients with complete paraplegia. Coordinating nerves and muscles with motion can also be beneficial for people undergoing physical rehabilitation for spinal cord injuries or stroke, where walking with the support and assistance of an exoskeleton can significantly improve recovery, even if the exoskeleton does most of the work.

“You want to train up that neurocircuitry again, that firing of patterns that results in locomotion in the corresponding muscles," explains Ames. “And the only way to do that is have the user moving dynamically like they would if they weren't injured."

Caltech is partnering with a French company called Wandercraft to transfer this research to a clinical setting. Wandercraft has developed an exoskeleton that has received clinical approval in Europe, where it has already enabled more than 20 paraplegic patients to walk. In 2020, the RoAMS initiative will focus on directly coupling brain or spine interfaces with Wandercraft's exoskeleton to achieve stable dynamic walking with integrated neurocontrol, which has never been done before.

Ames notes that these exoskeletons are designed to meet very specific challenges. For now, their complexity and cost will likely make them impractical for most people with disabilities to use, especially when motorized wheelchairs can more affordably fulfill many of the same functions. But he is hoping that the RoAMS initiative is the first step toward bringing the technology to everyone who needs it, providing an option for situations that a wheelchair or walker can't easily handle.

“That's really what RoAMS is about," Ames says. “I think this is something where we can make a potentially life-changing difference for people in the not-too-distant future."

This article appears in the January 2020 print issue as “This Exoskeleton Will Obey Your Brain."

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Video Friday: Humanoid Soccer

Your weekly selection of awesome robot videos

4 min read
Humans and human-size humanoid robots stand together on an indoor soccer field at the beginning of a game

Video Friday is your weekly selection of awesome robotics videos, collected by your friends at IEEE Spectrum robotics. We also post a weekly calendar of upcoming robotics events for the next few months. Please send us your events for inclusion.

CoRL 2022: 14–18 December 2022, AUCKLAND, NEW ZEALAND
ICRA 2023: 29 May–2 June 2023, LONDON

Enjoy today’s videos!

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Battery-inspired artificial synapses are gaining ground

5 min read
Array of devices on a chip

This analog electrochemical memory (ECRAM) array provides a prototype for artificial synapses in AI training.

IBM research

How far away could an artificial brain be? Perhaps a very long way off still, but a working analogue to the essential element of the brain’s networks, the synapse, appears closer at hand now.

That’s because a device that draws inspiration from batteries now appears surprisingly well suited to run artificial neural networks. Called electrochemical RAM (ECRAM), it is giving traditional transistor-based AI an unexpected run for its money—and is quickly moving toward the head of the pack in the race to develop the perfect artificial synapse. Researchers recently reported a string of advances at this week’s IEEE International Electron Device Meeting (IEDM 2022) and elsewhere, including ECRAM devices that use less energy, hold memory longer, and take up less space.

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NYU Biomedical Engineering Speeds Research from Lab Bench to Bedside

Intensive clinical collaboration is fueling growth of NYU Tandon’s biomedical engineering program

5 min read

This optical tomography device that can be used to recognize and track breast cancer, without the negative effects of previous imaging technology. It uses near-infrared light to shine into breast tissue and measure light attenuation that is caused by the propagation through the affected tissue.

A.H. Hielscher, Clinical Biophotonics Laboratory

This is a sponsored article brought to you by NYU’s Tandon School of Engineering.

When Andreas H. Hielscher, the chair of the biomedical engineering (BME) department at NYU’s Tandon School of Engineering, arrived at his new position, he saw raw potential. NYU Tandon had undergone a meteoric rise in its U.S. News & World Report graduate ranking in recent years, skyrocketing 47 spots since 2009. At the same time, the NYU Grossman School of Medicine had shot from the thirties to the #2 spot in the country for research. The two scientific powerhouses, sitting on opposite banks of the East River, offered Hielscher a unique opportunity: to work at the intersection of engineering and healthcare research, with the unmet clinical needs and clinician feedback from NYU’s world-renowned medical program directly informing new areas of development, exploration, and testing.

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