BEIJING, Aug. 17 (Xinhua) -- The ongoing 2025 World Humanoid Robot Games are part competition, part carnival. They are a stage on which intelligent machines from around the world demonstrate their skills in events ranging from football to high jump.

As nations race farther into the era of artificial intelligence, companies and research institutions are using the event as both a showcase and a knowledge exchange, pushing the limits of robotics design and performance.

On the football pitch, three-a-side and five-a-side matches pit AI-powered robots against one another. Guided by high-speed visual sensors, they track the ball's trajectory with precision. What they lack in human speed and coordination -- often tripping and tumbling -- they make up for in mechanical agility, springing back to their feet in seconds to rejoin play.

Around the venue, robot doctors diagnose breakdowns with terms such as "right hip joint disconnection" and "left foot plate detachment," armed with tools for quick field repairs.

The cycle of competing, falling, being fixed and returning to the field reflects a crucial stage in the evolution of robotics, said Li Zi'ao, a graduate student at North China Electric Power University and the leader of his school's robot football team.

"The main challenges in robot soccer right now are communication and coordination," Li told Xinhua. "Most robots still play individually."

He has suggested strategies to improve algorithms, such as the creation of a captain-election algorithm that would allow the robot with the best vantage point to direct play and reduce communication chaos.

While soccer matches unfold autonomously, other events test human-robot cooperation. For 400-meter and 1,500-meter races, technicians guide robots with devices similar to gaming controllers, using one hand to manage speed and the other to steer direction.

Xue Qingheng, deputy general manager of Inter City Technology Co., Ltd., said that his company's robot completed 1,500-meter race in 14 minutes. He compared this to its performance at a humanoid robot half-marathon that took place in April, when the technology was less mature.

"After four months of iterations, our robot now runs stably without falls or glitches," Xue said. "There's room to improve speed and strength, but this marks real advancement."

Chen Dong of MagicLab Robotics Technology Co., Ltd., called the competition the "ultimate stress test" for product design. "If our robots can handle these extreme conditions, they can handle anything in daily operations," he said.

Heat is the biggest obstacle for racing robots, Chen noted. "Many overheat with prolonged operation. Top models use improved materials, but we still need better thermal solutions."

The combat arena has brought the fiercest action to the Games, with metallic clashes echoing as operators direct their machines from the sidelines.

In the sport of free combat, hardware durability and software algorithms are both critical, said Deng Huasheng from Unitree Robotics. "If the structure can't withstand collisions, it will fail. And if balance algorithms falter, a light push can knock a robot down."

Beyond human-inspired events, the games also feature competitions tailored to machine capabilities, such as box transportation and medicine sorting events -- tasks that highlight practical applications in real-world scenarios.

Logistics robots from Jianghuai Advanced Technology Center use wheeled chassis and telescopic arms to handle materials. Speaking to Xinhua, researcher Wang Xu noted that future designs will focus on refining arm structure, chassis stability and thermal control to boost efficiency in ways "beyond human capabilities."

"Humanoid robots today resemble the internet in the 1980s -- poorly understood yet transformative," Xue said. "But I believe that in the near future, robots could become as ubiquitous as smartphones."

Unitree CEO Wang Xingxing said the robot Games can drive progress across the industry. "I hope events like this propel the whole sector toward better development," he said.

The 2025 World Humanoid Robot Games opened in Beijing on Thursday, featuring 280 teams from 16 countries competing in 26 events at the National Speed Skating Oval from Friday through Sunday.

(Huang Rongrong, Xiong Run and Zhang Yiyi also contributed to the story)