War machines

“The possibility of attaining the advantages of animal locomotion with walking mechanisms,” proclaims the voiceover, “has intrigued innovators for centuries.” So begins a slightly wobbly informational video, produced by the University of Wisconsin in the early 1970s. Over the next ten minutes or so, we watch three generations of ‘walking machines’ in action – though, really, they seem to do more harm than good. Despite being worn by a healthy young man, one of the examples requires him to hold a pair of sticks, as if he might faint at any moment. As the voiceover woman explains, each syllable cascading into a torrent of elongated Midwestern vowels, the canes are a “safety precaution”.

Yet, if our experiments with exoskeletons started as a bit of a joke, no one would dare claim that now, especially if they’ve spent any time in a barracks. From their origins in the laboratories of the Cold War, they’re now big business for military planners from Washington to Moscow. The statistics for defence are obscure, but Business Wire reports that the global demand for exoskeletons generally will rise by a spectacular 22.17% between 2019 and 2024. And no wonder. From improving logistics behind the frontline to preventing battlefield injuries, exoskeletons could be the scaffold on which future warfare is built.

But with military spending at the Pentagon being what it is – even with China sniffing down its neck, the US still contributes 37% of the global total – how come exoskeletons aren’t deployed everywhere the marine corps or the army does battle? In the past, the potential of exoskeletons had arguably run away from the messy reality, with batteries, manoeuvrability and robustness all limiting their use. Yet by blending solid engineering with the latest AI technologies, several countries are changing all that – with enormous consequences for soldiers everywhere.

Only good for the closet

David Audet is the kind of person who clearly loves his job. Joining the US army’s Soldier Systems Center over 30 years ago, he describes his career as “awesome” – and who’s to gainsay him, especially when you hear his enthusiasm? Between developing unmanned aerial systems and “smartphones for soldiers” and all kinds of other clever gadgets, the chief at the mission equipment and systems branch at the Combat Capabilities Development Command (CCDC) Soldier Center in Natick, Massachusetts, obviously has a lot on his plate. Yet there’s one area, until fairly recently anyway, that Audet and his colleagues had long struggled with: exoskeletons.

“We’ve been looking at exoskeletons for quite some time, since about 2000 or 2002,” says Audet. “And prior to five years ago, it was very difficult to get exoskeletons to provide a positive benefit.” It’s not hard to see he means, starting with how these machines actually interact with the human body. In theory, exoskeletons should support the back and limbs, and make carrying heavy loads easier. But as any steel-encrusted medieval jouster could have told you, dressing up in a heavy suit can be uncomfortable, especially if the costume doesn’t react seamlessly to your movements.

“A lot of the systems tend to be reactive,” explains Audet, “so that when you go to move your leg, your leg brushes up against a sensor, which then activates the motor which helps your leg move, so it’s reacting to your physical movement.” Pushing against that kind of force would soon become tiring even if you’re just going for a stroll – let alone if you’re an infantryman with 100lb of kit. It hardly helps, Audet adds, that the power systems traditionally used for the devices are so heavy, limiting movement even further.

Nor is the US alone in grappling with the cumbersome nature of these machines. “I think the mechanics and the energy packs that powered those exoskeletons were the biggest stumbling block to their development,” says Sam Bendett, a research analyst at the Center for Naval Analyses’ Russian Studies Program with the Adversary Analysis Group, about Russian forays into exoskeleton technology. “You could build something and operate it, but you would have to be literally hooked up to a battery.” It goes without saying, Bendett says, that in the middle of a firefight this is less than ideal, not least because it endangers the wearer the suit is meant to protect.

Deployment in Syria

In the spring of 2017, as Syria’s civil war ground on without end, military insiders reported a curious sight near the central town of Palmyra – the same place so gratuitously demolished by Isis for its supposedly sacrilegious heritage. The extremists had fled the town earlier in the year, and troops loyal to President Bashar Al-Assad had begun clearing the area of mines. They enjoyed some special help.

In pictures released to the media, a trio of Russian soldiers are shown shuffling forward, mine detectors in the dust by their boots. Nothing unusual then – until you notice what they’re wearing. All three are decked out in exoskeletons, thick rods running up their legs and visors on their heads.

Apart from highlighting the deep and complex alliance between Syria and Russia, this picture is arguably even more significant from a technological perspective – for it proclaims that after years of frustration, exoskeletons have finally come of age. “We’re going to see the evolution of the capabilities of these exoskeletons,” says Bendett, something that can probably be explained by fundamental technological reforms.

Rather than being weighed down with an unwieldy power pack, the simplified exoskeletons showcased in Syria work without one, and without needing a change of battery. More to the point, Bendett suggests that the machines actually do help. Despite carrying heavy equipment around their chest, he says that operators reported they “could work for hours without feeling tired”.

Thousands of miles away in Massachusetts, Audet has a similar story to tell. After battling cumbersome systems for years, he now says that his team is finally “marrying” soldiers to the machines that support them. In reality, that means using machine learning to ‘teach’ the exoskeleton about when the wearer is likely to move, pre-empting that movement and making the whole system less strenuous. “It’s learning what muscle groups you activate in order to do certain tasks,” he explains. “Then you can have the system almost anticipate what you’re going to do.” And while he admits the US army has yet to roll out a proper exoskeleton for use in the field, Audet adds that this sort of versatility is just what’s needed. Rather than building a thousand ‘cookie cutter’ exoskeletons, each one will adapt to the wearer and their gait, the way they move, or how they fire a gun.

At the same time, Audet is enthusiastic about how these machines could be used in practice. Figures for military logistics are scarce, but the direct cost of ‘lift-related’ injuries in American workplaces generally come to over $15bn per year. But what if supply troops could wear exoskeletons that make carrying heavy ammunition and supplies not only less tiring but less dangerous? Audet believes such a world is within reach, arguing that making soldiers artificially stronger can have knock-on effects right to the frontline. If grunts can carry more food, for example, or mortar crews can keep a few extra shells in their backpacks, then fewer helicopters or trucks have to come out and supply them – in turn keeping them out of harm’s way.

You can’t help but marvel

Given all this potential, it’s surprising that countries far beyond the traditional Cold War rivals are excited about exoskeletons. Both China and India are developing homemade models, while even Turkey and Japan are investigating their potential. But beyond giving soldiers more strength and stamina, might we ever get to the point where exoskeleton-clad troops can actually fight better, incapacitating enemies with a single punch or giving a bayonet charge some extra heft?

“I really hope so,” says Audet, adding that even if veritable super soldiers are a way off yet, exoskeletons are still exciting for the way they could help soldiers in ways that go far beyond mere logistics. Among other things, he imagines scenarios where troops in biohazard suits could carry more oxygen or wear more armour than they ever could before, helping them fight in challenging environments for longer.

Bendett makes a similar point, describing how a younger generation of Russian scientists, weaned on Marvel films like Iron Man, has been inspired to try and “match their imagination with the actual capabilities”. And though he admits that full-fledged Tony Stark suits are a way off yet, he does say that we’re moving in the direction of exoskeletons that can move seamlessly with the wearer. Does that mean that regiments of perfectly-honed Russians, capable of ten-foot jumps and deadly karate moves, are likely to be deployed to Palmyra anytime soon? Perhaps.