Every technological advancement seems to have a sharp inflection point, a time before which it seems like any early adopters are considered kooks, but beyond which the device or service quickly becomes so mainstream that non-adopters become the kooky ones. Take cell phones, for example – I clearly remember a news report back in the 1990s about some manufacturers crazy idea to put a digital camera in a phone. Seemingly minutes later, you couldn’t buy a phone without a camera.
It seems like we may be nearing a similar inflection point with a technology far more complex and potentially far more life-altering than cameras in cell phones: powered exoskeletons. With increasing numbers of news stories covering advancements in exoskeletal assistants for the elderly, therapeutic applications for those suffering from spinal cord injuries and neurodegenerative diseases, and penetration into the workplace – including the battlefield – as amplifiers of human effort, it’s worth taking a look at where we are with exoskeletons before seeing someone using one in public becomes so commonplace as to go unnoticed.
First, some definitions. I’m using the term “exoskeleton” in perhaps an overly broad way, referring to just about any powered, articulated device that’s human-wearable and intended to either enhance or restore the natural range of human motion. I’m also including some of the non-powered worker assist devices currently on the market, as they’re an important category and most of them could serve as the foundation for powered appliances in the near future. But I’ve left out mechas or mech-suits; as cool as it may be to watch Jaegers and kaiju duke it out in Pacific Rim, that opens up a can of worms.
The concept of a powered exoskeleton goes back quite a way, to a steam-powered time long before the idea was practical. It would not be until the 1960s, when control systems and power transmission had become sufficiently advanced, that a serious effort would be made to develop an exoskeleton. That came from the R&D labs of General Electric in the form of an electromechanical suit called the Hardiman. The device had four hydraulically powered limbs that were supposed to sense the operator’s movements within them and smoothly reproduce them in each limb, allowing the operator to lift a load equivalent to the 1500 pound (680 kg) weight of the suit. But the control systems could never be adjusted sufficiently to reduce the tendency of the limbs to move violently; consequently, nobody ever donned the suit while it was powered up.
Perhaps the first exoskeleton that made waves in the media was the LIFESUIT, designed by Monty Reed, a former US Army Ranger. When a night parachute jump went horribly wrong with 100 feet (33 meters) left to go before the ground, Monty suffered injuries that would severely hamper his mobility. While not paralyzed, he was unable to walk or stand for more than a few minutes. Rather than face a life lived flat on his back, Monty dreamed up an exoskeleton to help him regain his independence. He taught himself the concepts of robotics and control systems, and went through multiple prototypes of LIFESUIT on a shoestring budget before piloting the 12th version in a 5-km road race in Seattle in 2005.
To Walk Again
For all he has accomplished, Monty’s effort seem a bit chunky next to the current generation of assistive exoskeletons. Recent advancements in battery technology, brushless motors, and sophisticated control systems mean that a powered exoskeleton can now be much sleeker, approaching the point where it can be worn under clothes.
One leader in the market for assistive exoskeletons is a Japanese company called Cyberdyne. That they chose that particular name is a bit puzzling from a popular culture standpoint, as is the acronym for their flagship product HAL. Short for “hybrid assistive limb”, HAL comes in several configurations and is currently commercially available in Japan and the EU, where it’s the first non-surgical medical robot approved for therapeutic use.
The HAL configuration that seems to have the biggest market share is a lower-limb version. A pelvis-mounted support holds the batteries and control systems, while the wearer’s legs are flanked by actuators for the hips and the knees. Cyberdyne doesn’t provide much information on the internal arrangement of their products, but it looks like the joints between the leg supports and the pelvic strap are very complex, allowing motion in multiple axes.
HAL differs from other medical exoskeletons in its control methods. While other exoskeletons seek to completely automate the motions of walking, making the wearer more of a passenger, HAL uses sensors applied to the legs to detect the nerve signals associated with walking and translate them into control signals that assist with the intended movement. It’s sort of a mechanical biofeedback system, where the user’s brain makes the association between the signal it sent and the movement thus created, which may eventually help the user to walk again unassisted.
HAL is now getting a workout in the US. The videos below show first a new user, a 57-year old Florida man who has been paralyzed since a motorcycle accident two years ago, intent on being able to walk his daughter down the aisle at her wedding; next is a more seasoned user suffering from Guillain-Barre syndrome who is walking almost independently.
Carrying the Load
Medical assistive applications are far from the only market being penetrated by powered exoskeletons. The potential for exoskeletons to support and protect workers and amplify their inputs is already being explored by multiple companies, with Cyberdyne fielding a few entries. One is the HAL Lumbar Type, a powered exoskeleton worn on the lower back and upper thighs. It comes in two versions, one for general industry and one for the medical caregiver; both are intended to reduce strain on the lower back associated with moving heavy loads in awkward positions.
For other workers, lower body fatigue is far from the major problem. As anyone who has ever worked underneath a car on a lift knows, constant extension of the arms can be rough on the shoulder joints, and the amount of force that can be exerted in that position is limited. Automotive assembly line workers know this all too well, and there are not many old timers who don’t have a complaint or two about issues with their shoulders. To remedy this, some automotive plants are turning to Ekso Bionics’ EksoVest, a non-powered articulated frame that transfers loads from a worker’s arms to the ground through his or her legs. The EksoVest also provides an adjustable assist that allows the user to lift an additional 5-15 pounds (2 – 7 kg), but that’s only a side benefit. The vest is intended to reduce wear and tear on the worker during overhead operations; Ford has found a 90% reduction in ergonomic issues that previously sidelined workers.
With their obvious advantages in combat situations, exoskeletons are making inroads into military markets. The US Army is currently testing the Lockheed Martin ONYX exoskeleton, which bears a passing resemblance to the HAL device. The powered lower-limb exoskeleton is designed to reduce the fatigue and effort of humping heavy gear into the field and allow battlefield commanders to do more with fewer troops. ONYX can also potentially reduce number of injuries suffered by non-combatant soldiers in support roles, which often require strenuous activity. Indeed, one of the imagined use cases for the Hardiman suit was to allow a single soldier to load a 1,000 pound (500 kg) bomb onto planes.
The US Army is also looking to go full Iron Man at some point in the future for its Special Operations soldiers with the TALOS, or Tactical Assault Light Operator Suit. Currently in the Request for Proposals stage, TALOS is envisioned as a powered, armored exoskeleton that adds significant augmentation to the wearer’s native strength, as well as adding suites of sensors to monitor both the environment and the soldier. The Army believes a first-generation TALOS will be in testing by this summer.
Despite the hype, we’re a long way from an actual Iron Man suit, and the day where mechanized warriors tromp through the countryside in private bipedal tanks is probably a long way off. But when a medical exoskeleton that can help the paralyzed walk again is currently available for the price of a nice car, it might not be too long before we see arguments on the soccer field because little Johnny was caught with an exoskelton inside his Underarmour.
[Featured image: Exoskeleton Report]