Marvel’s Iron Man franchise has been around since 1963—but did you know that engineers and scientists have already been trying to create real-life, motorized suits of armor at around the same time? It was General Electric that first attempted to develop a working exoskeleton between 1965 and 1971. Named Hardiman, it was the very first documented attempt at a working exoskeleton and was intended to help the user lift loads of up to 1,500 lbs (680 kg).
While limited in practical applications and thus not entirely successful, Hardiman paved the way for the development of today’s powered exoskeletons. Just recently, suitX of US Bionics developed and launched Modular Agile eXoskeleton (MAX), a complementing set of three bionic pieces that reduce tension and strain in the shoulders, back, and knees. Even DARPA, the Pentagon’s research and development division, is heavily invested in brain-controlled prosthetics and exoskeletons.
Meanwhile, there are more and more varieties of exoskeletons being created for both medical and everyday purposes. There are now machines that allow individuals with spinal cord injuries, for example, to walk upright, manage the stairs, and even perform athletic feats. Some companies, on the other hand, are developing exoskeletons that help boost productivity, manage dangerous situations, and reduce the risk of workplace-related injuries and accidents.
Building the 21st Century Iron Man Armor
Developing exoskeletons usually require the use of a high-performance brushless DC motor or BLDC. These miniature motors pack a lot of torque despite their size, and with their low power consumption and long operating lifespans, BLDCs are ideal motors for the precise handling and action output of exoskeletons.
Another critical part of a fully functioning exoskeleton is a power supply. Not only are developers concerned about chemical hazards and electric shock risks, a fully functional exoskeleton suit also requires batteries that can last long enough to power the suit for more than a few hours. Non-rechargeable power cells usually have more energy and can, therefore, last longer than rechargeable ones. However, replacement cells should always be on-hand should the original be fully discharged in the field. Rechargeable cells, on the other hand, can be reused multiple times, although the main concern in using these is charging speed. The user would need a replacement battery while the primary one charges, or a battery that allows quick charging. This reason is also why BLDCs are the ideal motors for powered exoskeletons, as they have lower power requirements.
Meanwhile, the actual materials used for these exoskeletons may vary depending on the intended purpose and design, as well as output requirements. Steel is highly moldable, though it is quite heavy and requires higher power to operate. On the other hand, aluminum alloys are lightweight, though they do tend to show signs of fatigue much earlier and thus break down much faster. Titanium is both lightweight and strong but can be quite expensive. With the advent of 3D printing, hybrid building materials, and more complex construction methods, however, developing exoskeletons can become not only cheaper but also faster and more efficient in the future.
The Future of Exoskeletons
While the concept of exoskeletons is deceptively simple—applying electro-stimulation to detect a subject’s movements in order to replace or enhance them—their applications have yet to be fully maximized due to some limitations. These include limited motion ranges and flexibility, as well as weight and size adaptability issues, especially for younger, smaller users.
But even with the mounting challenges, one of the most important societal contributions of powered exoskeletons is breaking the belief that disabled persons are limited to wheelchairs for movement. Powered exoskeletons can be empowering (no pun intended) and can build confidence for its users. Meanwhile, the concept of using powered exoskeletons in different working environments is slowly getting more and more traction. It’s not so much as replacing humans entirely, but rather using these machines to help humans become safer and more efficient at work.
Powered exoskeletons are currently limited to military, medical, and a few workplace applications today. However, with the speed of technological developments, as well as the continuous work of engineers and scientists, these mechanical wonders can soon start making everyone’s daily lives not only more comfortable but also healthier and more efficient.