2024-05-11 03:53:14
Lion Robotics opens the era of AI robots… 10 years of AI reinforcement learning robot control research
Raibo 2 completed… Mass production starting later this year
Reduced battery usage – maximum speed of 21 km per hour… World’s highest level among 35~50kg class
Excellent for reconnaissance… Speed up lifesaving
Among four-legged robots, Boston Dynamics’ ‘SPOT’, which hit the market in 2020, is famous. It resembles a dog that is familiar to people. Images of walking on four legs and looking around, and maintaining balance without falling even when people push you, remain in the public’s mind. Recently, Chinese companies are also actively commercializing four-legged robots.
The reason robotics engineers do not give up on the animal-like leg shape is because it is advantageous for saving people through difficult terrain or enabling stable maneuvering in places such as disaster sites where there are many objects that move when stepped on. In addition, quadrupedal walking technology is a technology with great potential that is essential in fields such as space exploration and pioneering unknown areas.
Unlike other companies, Lion Robotics, located at KAIST in Daejeon, is a startup that creates four-legged robots controlled by artificial intelligence (AI). Professor Jemin Hwang (36) of the Department of Mechanical Engineering at KAIST founded the company as a faculty start-up in October last year. Professor Hwangbo, who met at the KAIST lab on the 7th, said, “Commercial quadruped robots are coming out in the U.S. and China, but there is still a lot of room for improvement in terms of walking in difficult terrain and battery life, so I decided to take on the challenge of starting a business.” He added, “I am using my experience in computer simulation.” “We have overcome difficult terrain by securing technology that can be implanted into the robot’s AI, and we have made practical use possible by extending the battery use time to 8 hours.”
●“Existing four-legged robot battery usage time is less than 2 hours”
![“Development of a four-legged robot that walks for 8 hours continuously… “It doesn’t matter whether it’s a mountain path or a sand field.”[허진석의 톡톡 스타트업]](https://dimg.donga.com/wps/NEWS/IMAGE/2024/05/10/124882835.6.jpg "“Development of a four-legged robot that walks for 8 hours continuously… “It doesn’t matter whether it’s a mountain path or a sand field.”[허진석의 톡톡 스타트업]")
Lion Robotics completed the four-legged robot ‘Libo 2’ at the end of last year and plans to begin mass production at the end of this year. Raibo 2 weighs 41kg and reaches a speed of up to 5.8m per second (21km per hour). Battery time is 8 hours. Professor Hwangbo said, “In the 35-50kg quadruped robot market, there is still no robot that walks as fast as Raibo 2 and has a long battery life.” Various inspections and equipment checks can be carried out along a designated path in the spacious factory, and it is also possible to patrol the long, sandy beach.
Most quadruped robots introduced by large American or Chinese companies can be used for about 1 hour and 30 minutes to 2 hours, and their walking speed is less than 2 meters per second.
Professor Hwangbo said, “We are also trying to make our prices competitive. “The price of a Chinese four-legged robot of similar size is around 100 million won, and our goal is to produce Raibo 2 at a more competitive price point.” We plan to lower the price even more at the end of next year.
Basic four-legged robots have many limitations in use due to their short battery life. According to Lion Robotics, a large domestic company with a large outdoor workplace has introduced a foreign four-legged robot, but its use is limited to major process patrols as the total patrol length of the workplace reaches 8km.
When used for security or military purposes, battery life can become an even more important issue. Considering the fact that you have to return to the starting point with the battery remaining, the patrol or reconnaissance radius is bound to be greatly reduced. Even when going out to search for victims in high mountainous areas, the battery usage time of 1 to 2 hours is bound to be limited.
●After learning various terrains on the computer, ‘implanted’ to the robot
Professor Hwangbo is an expert in the field of robot control based on AI reinforcement learning. On the computer, various terrains that can actually exist, such as general ground as well as rough mountainous terrain, sand fields, gravel fields, and grass fields, are created, and functions are created to calculate control values for optimal movement in each environment. If you use simulation like this to create data for AI learning, the experience that would have taken 10 years to accumulate can actually be solved within a few hours. Professor Hwangbo said, “This is a technology that only Nvidia, DeepMind, and we can do.” The functions created in this way are implanted into Raibo’s AI chip. Raibo quickly controls joints with a small amount of calculation by finding the optimal function with minimal data perceived by the four legs.
Most existing four-legged robots are controlled in a model-based manner. This is a method of calculating the dynamics of the robot body whenever there is movement. This large amount of calculation consumes a lot of battery. Having to install cameras and LiDAR sensors to recognize the external environment is also a burden on the battery.
Professor Hwangbo said, “Reinforcement learning-based control can control the robot stably even without prior information about the terrain.” He added, “Unlike other robots, LIBO 2 can handle variable surfaces such as sand fields, gravel fields, and disaster sites that are prone to collapse. “The advantage is that it moves stably even in extreme conditions,” he said. Raibo 2 is currently capable of stable walking without a camera or lidar. Options that utilize vision information are also being developed.
Lion Robotics minimized energy consumption by developing key components for LIBO 2. For example, planetary gears are used in the actuator, and by optimizing the gear ratio, heat loss is reduced and battery usage time is increased. The motor controller and motor were also developed directly, reducing energy consumption by about 20 to 50% compared to before. Major parts such as actuators, legs, and body have been modularized so that in case of a breakdown, only the necessary parts need to be replaced, unlike other four-legged robots.
●Study in Canada due to family immigration, return to Korea and start a business
Professor Hwangbo’s entire family immigrated to Canada when he was in middle school, and he attended high school and college in Canada. He graduated from the Department of Mechanical Engineering at the Canadian University of Science and Technology and received a master’s degree in 2013 and a doctoral degree in 2019 from the ETH Zurich (ETH) Graduate School in Switzerland. He subsequently spent one year as a postdoctoral researcher at the Robotic Systems Lab at ETH Zurich, and since March 2020 he has been a professor at KAIST. While he was in Switzerland, he also participated in the development of the industrial four-legged robot ‘ANYmal’.
The paper ‘Learning agile and dynamic motor skills for legged robots’ published in the robotics journal ‘Science Robotics’ in 2019 received so much attention that it was selected as one of the top 10 papers of that year by Nature.
Lion Robotics has a total of 6 employees, including graduate students. The main team is graduate students who have studied reinforcement learning-based four-legged robot control technology for about four years. Professor Hwangbo expressed confidence, saying, “The control of four-legged robots based on reinforcement learning is a field that is just beginning.”
Regarding the reason for starting a business, he said, “Ever since I was in graduate school, I wanted to become a researcher who creates robots that can be actually used rather than doing research for the sake of research.” He added, “I think I started a business naturally as my research results were accumulated.”
Currently, LIBO 2, the first product completed by Lion Robotics, has been sold overseas. There is a contract to sell five or six more units this year.
In the future, it is highly likely that four-legged robots will perform surveillance and patrol duties on behalf of humans in places where it is difficult for humans to reside for a long period of time. In industrial settings, it is likely to be used in marine plants, chemical plants, and power plants. In offshore plants that are far from land, four-legged robots can move around plant facilities and report any problems with equipment. The military can use four-legged robots for reconnaissance purposes on the beach or in the mountains.
Professor Hwangbo said, “Libo 2, which is not limited by terrain, can be used as an industrial inspection robot, military robot, and public order robot.”
Text and photo Daejeon = Reporter Heo Jin-seok [email protected]
2024-05-11 03:53:14