Exoskeletons Repair

Exoskeletons are wearable devices that enhance or assist human motion through mechanical interaction.  They serve various purposes, including medical (rehabilitation and assistance), occupational (injury reduction and performance enhancement), and recreational (activity support).  Exoskeletons can also be categorized by body part or task, structure (rigid or soft), and other characteristics.

The erliest exoskeletons invented by Nicholas Yagin.

Early wearable devices that could be considered exoskeletons by modern standards were developed in the mid-to-late 1800s and 1900s, predating the term “exoskeleton.” Many of these early exoskeleton devices were named braces, supporters, pedometers, or apparatus. They were designed to improve posture, mobility, and other physical tasks, however most of these devices only existed as prototypes or concepts, and were not commercialized, or had any heavy adopton.

One of the earliest wearable exoskeletons was a passive, rigid apparatus designed by Russian engineer Nicholas Yagin in July 1889. Its purpose was to enhance running, walking, and jumping. Another exoskeleton developed in the early 1900s was a steam-powered soft exosuit created by United States inventor Leslie Kelly. This exoskeleton aimed to improve the wearer’s running ability by transmitting mechanical power to artificially created ligaments that ran parallel to the wearer’s muscles.

Development of exoskeleton technology contunued through the mid 20th century, introducing new possibilities and challenges in developing wearable assistive technologies for both augmentation, and rehabilitation. One of the more promenent sucesses in exoskeleton technlogies during this time was the emergence of wearable camera stabilizers. However, since their was still little to no exoskeleton marketing at the time, the technology largely developed into its own category, but saw sucess with widespread adoption during the 1970s.

Diagram showing a human operator in the Hardiman I Prototype.

During this period, military applications for exoskeleton technology were also being considered. In 1951, the United States Army’s Ballistics Research Laboratory (BRL) initiated research on a powered exoskeleton designed to assist soldiers. By 1963, BRL researcher S. Zaroodny had produced a proposal for a prototype of the exoskeleton. However, it remains uncertain whether the prototype was ever actually created due to the engineering challenges associated with its development.

In the 1960s, the United States Armed Forces and General Electric co-developed another exoskeleton project named Hardiman I. This exoskeleton was powered by a hydromechanical bilateral servo system that would amplify a wearer's strength by a factor of 25. This meant that lifting an object that was 240 lbs (110 kg) would feel closer to 10 lbs (4.5 kg), and could lift objects up to 750 lbs (340 kg). Hardiman I also had a featured called force feedback, which enabled the user to feel the force and objects being manipulated. However, Hardiman I had various design limitations that would result in the project being labled an overall faliure. Any attempt to use the full exoskeleton resulted in violent and oncontrolled motion, which made researchers hesitent to turn the machine on with a human operator inside. In addition to operating complications Hardiman I weighed 1,500 lbs (680 kg), and the force feedback feature was unable to work as intended, and would result in the distruction of whatever object it was interacting with.

Diagram showing the design features of the Pitman Exoskeleton.

Exoskeleton technology continued to evolve into the 1980s and 1990s, serving as evolving testbeds and exploratory prototypes. One notable concept exoskeleton was the Pitman, developed by the Los Alamos National Laboratory. The Pitman was a 500-pound powered “suit of armor” primarily intended for military infantry for low intensity conflicts and counterterrorist operations. It featured a fiberglass polymer/ceramic composite armor and brain-scanning sensors in the helmet that controlled the suit. However, the Pitman never progressed beyond the initial concept phase due to its perceived complexity and impracticality at the time.

In the field of rehabilitation, significant advancements were made in exoskeleton technology. One such example is the Lifesuit exoskeleton, a robotic rehabilitation device designed to assist individuals with paralysis in performing therapy exercises aimed at regaining mobility and learning to walk. While early Lifesuits were initially tethered, later designeds allowed for Lifesuit exoskeletons to be more portable, which Lifesuit inventor Monty Reed used to walk in public road races.

From 2000 onwards, the focus in the exoskeleton field has shifted and expanded, partly due to significant advancements in design, implementation, and adoption. The emphasis on robotic, full-body augmentation exoskeletons that drastically enhance a person’s performance has diminished, in favor of smaller, simpler designs for specific uses. Modern exoskeletons act as wearable tools and offer benefits for limited tasks, such as ankle support for stroke patients or shoulder support for assembly line workers.

The early 21st century also saw the emergence of new exoskeleton categories for recreational, research, and educational use cases. This includes exoskeleton products to assist users in walking, running, hiking, and even skiing.

• Exoskeleton Wikipedia Page