In this blog post, we’ll explore the development trends and operating principles of wearable robots, as well as research examples from both Korea and abroad.

Why wearable robots are no longer a distant future

When people hear the term “wearable robot,” many think of characters like “Iron Man” or “RoboCop” from movies. Due to the influence of this pop culture, wearable robots may still feel like science fiction set in the distant future, but in reality, various practical applications are already being tested in the military, industrial, medical, and welfare sectors. For example, during the opening kickoff of the 2014 World Cup in Brazil, a young man with paraplegia was shown kicking a ball while wearing special rehabilitation robot equipment; this device utilized a system that detects brain signals to control leg movement.

BLEEX: An Early Attempt at an Exoskeleton System

One of the earliest commercial and research examples of wearable robots is BLEEX, a lower-body military exoskeleton developed at UC Berkeley in 1994. BLEEX was designed to significantly reduce the physical strain on the wearer when carrying heavy loads by equipping the hip, knee, and ankle joints with hydraulic actuators. According to research findings, the system was designed so that even when carrying a load of approximately 80 kg, the force transmitted to the wearer was limited to about 2 kg. To detect the wearer’s intended movements, more than 40 sensors were deployed, and the system was structured to maintain balance by having these sensors exchange data in real time.

Classification of Exoskeletons: Assistive vs. Augmentative

Exoskeleton systems are broadly classified into two categories based on their purpose: assistive and augmentative. Assistive exoskeletons are developed to aid the daily activities of the elderly or people with disabilities; the exoskeleton directly assists the wearer’s strength to enable movement. In contrast, augmentative exoskeletons amplify the wearer’s strength, enabling them to perform heavy-load tasks in fields such as the military and heavy industry. Many systems currently in the commercialization or research stages fall primarily into the assistive category, with examples including Berkeley Bionics’ HULC, the HyPER series developed by South Korean researchers, and KAIST’s Cowalk.

Limitations of Exoskeletons and the Trend Toward Lightweight Design

Traditional exoskeleton structures have the drawback of being bulky and heavy because each joint must be equipped with an actuator and sensors to detect angle and displacement. Furthermore, their complex structure increases manufacturing costs and reduces wearability. To address these issues, recent research is focused on simplifying the structure, reducing bulk and weight, and lowering manufacturing costs. In other words, there is a growing trend toward using simple mechanisms—such as wires and small motors—instead of large actuators at each joint, or improving usability through materials and designs that enhance comfort.

Exo-Glove: Design and Operation of a Glove-Type Wearable Robot

A prime example of this trend toward lightweight and simplified designs is the Exo-Glove, a glove-type wearable robot developed by the Bio-Robotics Laboratory at Seoul National University and others. This device is designed to be worn like a glove to assist people who cannot move their fingers on their own due to conditions such as neurological disorders, while leaving the hand’s natural skeletal structure intact. The core idea is to use wires, small motors, and elastic elements to bend and straighten the fingers, rather than relying on heavy and complex individual joint actuators.
Specifically, multiple wire guides are installed on the palm, and U-shaped wire guides are positioned at the tips of the fingers. A pair of wire guides, arranged side by side, is positioned on the first joint of each finger. An elastic wire is installed on the back of the hand to maintain a flat hand position; one end of the elastic wire is connected to the fingertip, and the other end is connected to the actuator. When the actuator is inactive, the wires on the palm side are loose, and the hand remains flat due to the elasticity on the back of the hand.
When the user attempts to grasp an object, the drive unit pulls the wires on the palm side to shorten their length; as a result, the elastic wires on the back of the hand stretch, causing the fingers to bend so that the object can be grasped. The wires can be pulled simultaneously by a motor or individually to move specific fingers, enabling partial control.

Conclusion and Future Challenges

In summary, wearable robotics technology has already moved beyond the realm of cinematic fantasy and entered the stage of practical application; it is being put to practical use not only in rehabilitation and medical fields but also in military and industrial sectors. Going forward, key competitive advantages will include lighter and more comfortable structures, cost-effective designs, and control technologies that accurately interpret user intent. Although South Korea is a latecomer compared to global leaders, it can still become highly competitive through lightweight and simplified designs, as well as human-centered interfaces.
Additionally, looking back at this first draft, while I included a relatively detailed explanation of the operating principles of robotic gloves, adding more technical details—such as the roles of individual components and the physical specifications of the actuators and sensors—would be helpful not only to general readers but also to those with a technical interest. In the next article, I will delve deeper into the operating principles of each component of the gloves, real-world application examples, and user feedback from the field.