Robot tug-of-war debuts at the World Humanoid Robot Games in Beijing
The upcoming second World Humanoid Robot Games in Beijing will feature a debut robot tug-of-war competition, offering a new and exciting challenge in motion control, force recognition, coordination and decision-making.
When robots move beyond simply following commands and engage in physical contests requiring not only strength but also tactics, the competition reaches an entirely new level. Tug-of-war is not a test of motor power alone — it is a test of balance, sensitivity and the ability to adapt to changing loads. In this sense, robots must learn what humans intuitively grasp from childhood: how to distribute weight, sense resistance and make split-second decisions. It is precisely such tasks that bring machines closer to human perception of the world.
The event, to be held from 22 to 26 August, has attracted 666 teams and 2,056 robots from 16 countries, making it one of the largest humanoid robot competitions in history. The tug-of-war competition is held in a “two-on-two” format, with teams competing on a track 1.2 metres wide and 12 metres long. Each match lasts two minutes, and robots are disqualified if any part of their body other than their feet touches the ground or if they go out of bounds.
“The most important thing for a robot in tug-of-war is resistance to torque. Its body must remain stable under extreme and high-intensity loads. In addition, its legs must also be particularly strong. Otherwise, the entire body will shift as soon as the rope is pulled. And even more importantly, the arms must be flexible enough to firmly grip the rope,” said Zuo Jiaping, co‑founder of LinkerBot Beijing Technology Co.
In tug-of-war, robots must grip the rope directly with their hands — a task that tests their long‑term holding capacity, load‑bearing ability and overall stability. “We tried different postures and grip strengths to ensure more stable holding, because hand slipping has a huge impact on the robots’ tug‑of‑war results. We iteratively improved various models in terms of overall motion control. During debugging, we referred to real‑life human tug‑of‑war cases and postures. Friction between the feet and the ground is another factor we had to consider, as it directly affects the robot’s performance efficiency,” said Ma Cong, head of the Embodied Brain department at XYZ Embodied AI Co.
In addition to tug‑of‑war, the robots’ grasping skills will also be tested in a bottle‑cap removal task. “It’s not just about holding the bottle with one hand. The robot also needs to operate a bottle opener with the other hand. The angle of the opener, the force applied and the precise positioning all directly affect the speed and quality of opening. In this task, the robot must truly learn to use tools, just as a human does,” said Zuo.
The second World Humanoid Robot Games is the largest international event in robotics, showcasing the latest advances in artificial intelligence, mechatronics and autonomous systems. The fourfold increase in participants compared with last year highlights the rapid development of the industry and the growing interest in such competitions. This year’s programme has been expanded to 51 competitive disciplines, including ball games, combat tasks and practical assignments in industrial assembly and household services. The introduction of tug‑of‑war and the bottle‑opening task reflects the organisers’ aim to test not only algorithmic capabilities but also the physical adaptation of robots to real‑world conditions.
As CCTV+ reports, the debut of tug‑of‑war will be one of the highlights of the upcoming Games, demonstrating how far technology has advanced in creating machines capable of interacting with the physical world at a level close to that of humans. This competition will show how ready robots are for collaborative work requiring not only precision but also an intuitive understanding of forces and loads — skills that will become the foundation for their use in construction, logistics and even rescue operations in the future.
