(Yicai) March 13 -- Several Chinese robot developers are putting their humanoid robots through their paces in preparation for the world’s first humanoid robot half marathon which will take place next month in Beijing. The event will serve as a global stage for showcasing their robots’ speed, agility, and performance.

Full-size bipedal humanoid robots such as Casbot’s Casbot 01 and Magiclab’s Wheat will be vying for prize money of up to CNY5,000 (USD691), that will be awarded to the top three finishers at the half-marathon on April 13.

There will also be awards for the robot with the best gait, the most popular robot and to all robots that cross the finish line. Only humanoid robots developed by robotics startups, research institutes, universities, robot clubs and other innovative entities worldwide will be allowed to participate.

“The 21-kilometer race is a pretty extreme test,” Zhou Di, an expert from the Ministry of Science and Technology, told Yicai. “In industrial and household applications, the ability to run long distances isn’t usually a top priority for robots.”

But the half marathon isn’t just a publicity stunt, Zhou said. It’s a real opportunity to compare robots. Investors and customers will be on the lookout to see which robots prove to be the most reliable and stable.

Both the Casbot 01 and Wheat robots stand over 1.7 meters tall and weigh about 60 kilograms, similar to an average human’s height and weight.

Just like humans, robots need to learn how to walk before they can run, Chen Chunyu, vice president of Magiclab and head of research and development at the Suzhou-based firm, told Yicai.

“For example, if the software sends a command but the robot’s motor turns at the wrong angle, the robot is very likely to fall,” Chen said. So, developers need to fine-tune the hardware and algorithms, which takes about two to three months.

“Once stability is accomplished, we start experimenting with new algorithms to teach the robot more complex movements, like running,” Chen said.

Stress Test

A 21-kilometer marathon will be a real stress test for the robots, pushing their hardware to its limits.

It is harder for humanoid robots that are built like humans to run because the more complex the hardware, the heavier the body and hence the harder it is to move, said Yang Guodong, co-founder of Beijing-based Casbot and head of the Sports Intelligence R&D Center.

Running puts huge strain on robots' knee and ankle joints, requiring high torque. As the robot’s weight increases, the torque needed for each joint grows exponentially, Yang said. The robot’s mechanical structure needs to be adjusted for higher impact and vibration, he added.

Running for long periods also means the motors need to work hard, which can lead to overheating and break downs. Also, operating at a high load for a long period increases the wear and tear on robot parts and will shorten its lifespan.

Motion control training for robots is roughly divided into three stages, Yang said. The first is to master basic movements like walking and jumping. This is already fairly easy to do, and running robots, like those seen in videos, are no longer a big challenge.

The second stage is about combining movements, like dancing, which requires coordination between the robot’s hands, feet and other parts. This is more complicated. The third stage involves training robots to perform tasks in specific real-world scenarios.

“Only robots that pass this third stage are ready to be delivered to customers,” Yang said.

“If this competition had been held a year ago, not many robots would have been able to participate,” Chen said.

Editor: Kim Taylor