Gundam is a scifi anime where humans battle each other in “mobile suits,” which are basically combat vehicles that look like people instead of tanks. It’s one of the pop culture fantasy worlds that set the stage for today’s exoskeletons: wearable machines that grant you superhuman powers.
You’ve seen their likeness in Iron Man, Aliens, Starship Troopers, the Halo and Metroid video games and so on, but like so much of the technology that’s now used everyday, exoskeletons jumped from fiction into reality. Exoskeletons already give us abilities beyond what nature bestowed: They let us lift massive amounts, make us better soldiers, and can restore the gift of walking to those who’ve lost it.
But what’s next? Will we be piloting 10-foot mechas capable of slinging and crushing boulders? Will we all be cloaked in wires and sensors and metallic shells that pulse with artificial hearts?
Simmer down now, Tony Stark, exoskeletons aren’t quite there. Yet.
What’s an exoskeleton?
Animals such as grasshoppers have skeletons on the outside of their bodies. Humans’ “exoskeletons” are powered mechanical devices you put on like you would clothing—clothing that enables your body to outperform how you could naturally. In a nutshell, it’s a wearable robot.
Exoskeletons can be powered by various means: batteries, hydraulics, nearby wall outlets, or sensors that respond to flurries of neurological activity in your brain. The latter is how a paralyzed man was able to walk onto the field and make the first kick at last year’s World Cup: The 29-year-old was left paraplegic after a car accident, but an electrode-covered EEG cap sent electrical signals from his skull to his exo’s sensors, triggering the suit to move his legs for him.
A paralyzed man kicks at soccer ball at the 2014 World Cup.
Indeed, at this point, most of the exos in use are designed for people who’ve suffered debilitating injuries that left limbs unusable. The other main audience is the military; combat-ready robotic body enhancers are meant to help soldiers tire less easily, travel farther on foot, or carry heavier loads on the battlefield. Lockheed Martin’s HULC combat exoskeleton uses hydraulics to help soldiers lift up to 200 extra pounds, and is battery-powered so it can be used on the go.
Meanwhile, the soft exosuit pictured to the left, developed at Harvard, wraps the legs in sensors and straps to aid the elderly in walking, or to help firefighters and paramedics whose jobs require more heavy lifting than humans are built to withstand. Instead of being made of firm, stiff materials that resemble leg braces or crutches, the soft suit is textile—it looks like long johns, is powered by tiny waist-mounted motors, and is peppered with small sensors that mimic normal leg movement. It reduces the energy it takes to walk, helping humans stockpile stamina like Energizer Bunnies.
It’s pretty sweet. And as the tech advances and becomes more cost-effective to make, exo suits will proliferate beyond the front line and hospital walls. They’ll be available across various industries, from farming and nursing to retail and emergency first responders. Or even in your own home, to assist with heavy lifting or DiY physical therapy.
So come with us, Gundam geeks and Ellen Ripley fans, and see what the future has in store.
A lighter, smoother suit
Pop culture has pummeled us with images of human-piloted, missile-launching Megazords, or gigantic Halo-style armor that make people look like army tanks with limbs. But in reality, near-future exoskeletons will likely sport as little hardware as possible, and will instead be unobtrusive and softer.
Today, exoskeletons tend to look like leg braces with a bunch of wires on them. Considering the powered wearables are chiefly designed for combat forces or injured patients stripped of motor skills or neurological ability, you can see how being outfitted in an unwieldy alien fistfighter is unideal.
“I prefer that the enemy wears something huge, not our soldiers—large exoskeletons are constraining,” says Professor Homayoon Kazerooni, a mechanical engineering professor at the University of California, Berkeley. “They can’t do anything in it.”
Kazerooni’s worked with exoskeletons at Berkeley for over 20 years. He has over 50 patents under his belt, and developed such exos as BLEEX, a DARPA-funded lower body device that helps disaster relief responders, soldiers, or emergency workers schlep cumbersome loads over changing terrain. Another one of his credits: HULC, a titanium-legged military wearable that carries 200-pound loads and is licensed by Lockheed Martin.
Scientists are now working on simplifying exoskeleton design: These suits need to soup up their users, but also grant flexibility and freedom. “The whole idea of making a big machine, like Iron Man, is pretty much old now. Maybe it looks good on a screen, but in reality we want something minimal,” Kazerooni says.
The soft Harvard suit is one early example of this. Another was unveiled earlier this month, by Japanese robot maker Cyberdyne (a familiar face on the exo scene—no relation to the diabolical corporation in Terminator).
They’re the ones who brought us Hybrid Assistive Limb, or HAL (below).Cyberdyne used the same tech to create this robotic suit that elderly bank employees can use when picking up heavy stacks of cash or bank notes. It can reduce the effort to lift a heavy load by 40 percent, yet the suit looks more like an elaborate seat than a hulking machine.
Credit: Technigeek, YouTube
Boosting the upper body, too
The majority of exoskeletons currently on the market only focus on the lower body. For one, demand is simply higher—your legs are what give you mobility, after all. Two, upper body problems are tougher to solve, because the range of motion is more complex.
“The ability to pick up a cup of coffee and moving it around is more complicated than moving your feet forward,” says professor Jacob Rosen, director of UCLA’s Bionics Lab. He specializes in working with stroke patients, who often have one healthy, mobile arm, and one that is paralyzed. The goal is to use exoskeletons to restore life to the affected arm.
“We are designed to deal with an environment that is hard to predict,” Rosen says. “That’s why we have two arms, two lungs, two kidneys.” And since we’re not starfish that can sprout backup extremities, we have to get a bit more creative in how we adapt to such situations.
The UCLA Bionics Lab is currently outfitting stroke patients with robotic arms using a technique called “mirror image.” Patients put both arms (one healthy, one paralyzed) in exoskeletal sleeves and then begin navigating a virtual reality system—for example, playing a squash game. Every time the patient moves the healthy arm, electrical signals are sent to the other sleeve, which moves the paralyzed arm in the same fashion. This could help stroke victims “relearn” how to use their upper limbs.
In another activity that also resembles physical therapy, an “artificial force field” is created. The exoskeleton will help a paralyzed arm move within a restricted space. In the game, the patient must “paint” a virtual surface, but every time the arm strays from the area that’s supposed to be painted, the robotic sleeve pushes the paralyzed arm back, replacing the need for another human to physically force the patient’s arm to move in certain ways in order to rebuild mobility.
Rosen with his arm exos. Image: UCLA
The experts I talked to echoed that exoskeletons empower people to discover—or often, rediscover—their own strength. Rosen says they’re not eliminating jobs like physical therapists, but adding to the therapy dynamic, and building on it. With a therapist, you only get as much treatment as the amount of time the other person has for you. But with an exoskeleton? “It’s as much as your body can tolerate,” says Rosen. “That’s way more than what a therapist can provide.”
Artificial muscles will get even stronger
So the future exoskeleton will be easier to wear and available for other parts of the body. But it’ll also be stronger. A key factor that will drive exo evolution in the coming years is the material they’re made with. The robo-suits of the future could sport an interesting new ingredient that could give the wearer strength that equals 100 times what humans are capable of. That secret weapon: artificial muscles.
A team at the University of Texas, Dallas published a paper last year that found high-strength polymer fishing line and sewing thread can be twisted to form Herculean, manmade muscles. Here’s how it works: Coiled polymer fiber react to changes in temperature, contracting when heated and then loosening when cooled. Natural human muscles contract by about 20 percent, but these materials go as high as 50 percent—they contract further because of their twisted shape, giving the polymer muscles way more strength than a mere gym-going mortal.
These artificial muscles made of fishing wire would have the added benefit of being lightweight, not to mention cheap. “One of the problems right now with existing exoskeletons is that they’re powered pneumatically or hydraulically or by motors. They’re limited in their freedom,” Dr. Ray Baughman, leader of the study, says. “Motors are heavy. Hydraulic systems are heavy.”
Exoskeletons can make us super strong, super fast, and point to a world where tragic accidents or debilitating diseases don’t have the final say as to how our lives will unfold. But how can we grant humans these extra powers in a way that’s safe, economical, and realistic? That’s the question scientists are trying to answer now. What will likely guide the next few years’ of exo design is making them accessible and affordable enough for people to actually wear and use.
“A $100,000 exo is not really useful for any manager to buy for their workers,” Kazerooni says. “We can’t wait too long. There are too many people who need these technologies quickly. They needed it yesterday.”
Technology’s warp-speed development often makes real-life feel like scifi. And chances are, exos will be as commonplace as smartphones one day. We could see wearable robots at airports on the luggage handlers, or on the street, worn by athletes who have torn ACLs but who can walk normally. We could see them at supermarkets, factories, and shops worn by staff moving monster heaps of stock easier and faster than ever. We could even restore powers that if lost, were once gone for good. No more.
And, hopefully, we won’t need them for Gundam-like warfare. But they’ll still make us action heroes.