Robotic technology that enables people to walk again

Wearable robots can assist human muscular power and mobility. Wearable robot technology has great potential in various fields, from enhancing the muscular power of people without disability to assisting and rehabilitating people with disability in walking. Professor Kyoungchul Kong’s research team has developed wearable robot technology from a sensor and actuator to integrated robot systems. The team showed a wearable robot for torch bearing of 2018 PyeongChang Paralympics. Recently, the team has also developed the world’s lightest and most accurate wearable robot, which is suitable even for the rehabilitation of children. As one of the medalists of the Cybathlon 2016, the team is now developing a new robot for the Cybathlon 2020.

Article | Spring 2020

Poor eyesight is no longer considered as a disability. However, if someone has difficulty in walking, he/she may be called a disabled person. What is the difference? It is because the vision problem can be easily overcome by wearing glasses or contact lenses, but the walking problem has no such a complete solution yet.

Many research teams are searching for a practical and reliable solution for people with difficulty in walking. As the whole population is aging globally, and Korea is one of the most rapidly aging countries in the world, the need for a solution for people with mobility problems is increasing. Several research teams have studied stem cell technology to regain the lost motor functions in the human body, but they have failed to find a practical solution so far.

To this end, wearable robots may be a good alternative. Wearable robots are legged robots developed to assist human motion. As they have two legs (since humans have two legs), the overall structure of wearable robots is similar to that of a humanoid robot. However, wearable robots must be operated according to the intention of a wearer, and their motions must be perfectly synchronized with the human motions. In addition, the number of degrees of freedom (namely, the number of joints in the robot) is limited, because the overall weight of wearable robots is restricted because of the issue of comfortability.

The Robotic Systems Control Laboratory (RSC Lab) of the Department of Mechanical Engineering, Korea Advanced Institute of Science and Technology (KAIST), has studied promising and reliable solutions for developing wearable robots to assist people in different applications. The first application is human power augmentation of non-disabled persons such as workers who are frequently subjected to physically demanding tasks. In this case, the control and design of a wearable robot may intelligently recognize the motion intention of the wearer. Therefore, the research goal was to learn and follow the human motion characteristics.

 

The second application of the RSC Lab is developing robots for complete paraplegics. Since the motor system of complete paraplegics is not functional at all, human motion could be dominated by the control system of a robot. The RSC Lab has developed WalkON Suit, which is a wearable robot specialized for complete paraplegics. Professor Kyoungchul Kong, the director of the RSC Lab, and his research team won a bronze medal at the Cybathlon 2016, and they are developing a new WalkON Suit for the next competition in 2020. The new WalkON Suit enables a complete paraplegic wearer to walk faster than 30 meters per minute, which is the world-record for a wearable robot for the complete paraplegic so far.

The Cybathlon is an international competition in which people with physical disabilities compete against each other to complete everyday tasks using state-of-the-art technical assistance systems. Prof. Kong’s research team is participating in the Powered Exoskeleton Race, which is one of the six events of the Cybathlon. In the Powered Exoskeleton Race, the pilots, persons with complete paralysis, are asked to complete six missions, including sitting/standing, ascending/descending stairs, a tilted path, uneven terrain, etc., while wearing a wearable robot.

In the era of the fourth industrial revolution, many people may be afraid of over-advanced robotics and A.I. technologies, which may replace the roles of humans. Wearable robots, however, are the robotics technology that improves the quality of human lives. Everyone must experience difficulty in movement as getting old; however, one day in the future, we may all benefit from the research of Prof. Kong’s team.