A robotic show mimicked the thousand-hand Bodhisattva in the 2023 World Artificial Intelligence Conference. (PHOTO: XINHUA)

By LIN Yuchen

A robotic show that mimics the thousand-hand Bodhisattva catched eyes in the 2023 World Artificial Intelligence Conference which closed on August 8. The humanoid robots's ability to move arms as smoothly as the performance requires arises from a series of smart flexible joints, which distinguish the machines from traditional industrial robot arms.

To make robots move like real humans, according to CloudMinds Robotics, the company that manufactured the smart flexible joints for the robots that performed in the show, creating robotic joints with higher flexibility and control accuracy is critical.

Smart Compliant Actuator

In 2018, CloudMinds Robotics announced that it had pioneered the Smart Compliant Actuator (SCA), service robot parts comparable to Boston Dynamics, which had achieved technological breakthroughs in mechanical structure, core algorithms, and processing technology in the process of building smart robots. The SCA integrates and reduces the size of originally independent components in the same way as chips are integrated into a circuit board.

In order to realize flexible movement of robots, the comprehensive improvement of robotic perception, decision-making, execution and other capabilities are required. This makes it even more demanding in terms of the improvement of mechanical and electronic hardware, embedded software, upper layer software and intelligent algorithms.

CloudMinds Robotics scientists were inspired by observing how humans walk. They found that human joint flexibility (the range of motion of a joint), such as that of the knee and ankle joints, is not constant when the leg hits the ground. In order to simulate this characteristic of biological joints, the developers considered adding a variable stiffness feature to the tandem elastic drive joints.

The elastically driven joints, with variable stiffness tandem, are a disruptive and innovative idea that not only realizes the function of flexible joints, but also adjusts the stiffness of the joints in real time in line with the motion state of the robot, without changing the joint stiffness coefficient.

Referring to the design concept of smartphones, they designed flexible joints highly integrated with sensors and chips embedded with algorithms. With the synergy of multiple joints, the robot started to realize diverse and precise movement and work.

Industrialized manufacturing

With core components developed, industrialized manufacturing became another problem: in either domestic or foreign markets, there has not been readily available large-scale industrial support. For example, it is impossible to find high-strength, high-precision and lightweight electrical machinery that meet the component’s production requirements.

SCA integration — the smaller it gets the more difficult it is to manufacture — requires not only stronger structural design capabilities, but also better fabrication processes for a variety of devices, to allow for a thinner and lighter volume without sacrificing power.

"We thus have established a complete set of architectures to develop core motors that are more adaptable to service robot scenarios and requirements," said Luo Cheng, an engineer from CloudMinds Robotics. He introduced the use of high-performance amorphous magnetic materials can provide more stable torque output and higher efficiency while making the motor volume further miniaturized and lightweight; the smallest of it can be 35 millimeters thick in diameter.

This makes it far more easy to manufacture SCA through implementing the designing and industrialization methodologies of smart phones.

Domestic manufacturing

On March 31, 2020, CloudMinds Robotics’s industrial base broke ground in Shanghai Maqiao Artificial Intelligence Innovation Pilot Zone. “Now, there are more than 100 robotics companies, research institutes and other organizations that have used SCA to develop robots with different forms and functions," said Wang Bing, co-founder of CloudMinds Robotics, adding that, "The annual production of robot joints can realize 10 million sets."

The localized manufacturing of SCA is breaking the long-term monopoly of Switzerland's ABB, Germany's KUKA, Japan's Fanuc and Yaskawa Electric. At the World Conference on Artificial Intelligence in 2022, CloudMinds Robotics released a new-generation product — a bipedal robot equipped with 60 joints, which can already walk well and coordinate its hands quite naturally and smoothly.

Today, on the production line of CloudMinds Robotics, robots are capable of doing all the work previously done by humans. The industrial transformation of "machines producing machines" is on the horizon.