Why Humanoid Robots Open A New Blue Ocean For Coreless Motor Applications

 

Humanoid robots, as outstanding representatives of general-purpose robots and ideal carriers of "embodied intelligence," benefit on one hand from the rapid development of general artificial intelligence, and on the other hand, by becoming the bridge between AI and the real world with "embodied intelligence," gradually evolving into the terminal platform for the next generation of general artificial intelligence. In robot tasks, AI large models take on key roles in reasoning and decision-making, converting complex instructions into executable steps for robots by analyzing natural language commands. Moreover, the addition of multimodal AI large models significantly improves the accuracy and efficiency of reasoning and decision-making, providing important support for humanoid robots to progress toward generalization.

 

 

The rapid development of the robotics industry relies on innovations in key component technologies and the stability of their supply. In humanoid robots, the reducer, servo system, and controller are regarded as the three core components, together accounting for over 70% of the total cost. Additionally, as a core component, the value of the motor cannot be overlooked. In humanoid robots such as Optimus, the motor cost accounts for approximately 25% of the total component value.

 

Assuming that the global shipment volume of humanoid robots will reach 5 million units in the next decade, the demand for coreless motors (without iron cores) will see massive market growth during this period. Based on unit prices, the market increment for coreless motors may reach 350 billion RMB, while the incremental market for coreless motors is expected to exceed 78 billion RMB. Together, these two will form a vast market space of 428 billion RMB.

 

 

Unlike industrial robots used in fixed working environments, humanoid robots primarily serve human daily life scenarios. These robots need not only perception, decision-making, and action capabilities but also need to simulate human behavior patterns to interact with the environment and users in a more natural way. Therefore, motors, as core components of joint actuators, directly affect the robot's flexibility, precision, and stability.

 

Among various drive technologies, electric motor drive exhibits significant advantages over hydraulic drive. The electric motor drive solution benefits from mature motion control technology, providing real-time feedback of motion status via high-precision encoders to ensure accurate control. At the same time, the cost of electric motor drive systems is lower compared to hydraulic systems, with less maintenance required. This cost-effective characteristic makes electric motor drive one of the mainstream choices for humanoid robot development.

 

Among them, coreless motors, with their lightweight, high efficiency, and low inertia characteristics, have become key components in improving humanoid robot performance. Coreless motors can provide greater power density and higher response speeds in small volumes, enabling robots to exhibit superior performance in multi-degree-of-freedom joint control. Additionally, coreless motors have lower energy consumption, helping robots achieve longer battery life.

 

1.1 Humanoid Robots Integrating into Daily Life, Showcasing National Technological Strength

Humanoid robots have gradually become reliable assistants in daily human life, capable of assisting with a variety of complex tasks. Unlike industrial robots, which typically work in fixed environments, humanoid robots are designed to integrate into human daily surroundings. These robots not only possess core capabilities like perception, decision-making, and actions but also have human-like movement characteristics and friendly appearance designs, making them more easily accepted by humans and creating a sense of familiarity. By flexibly adapting to different environments, humanoid robots show enormous application potential in areas like home, services, and healthcare.

 

As advanced intelligent devices, humanoid robots are regarded as symbols of national technological strength. Their development requires overcoming technological barriers across multiple disciplines, including mechanical engineering, electrical engineering, materials science, sensing technology, control systems, and artificial intelligence. With human-like appearance features, bipedal walking capabilities, and highly coordinated motion control technologies, humanoid robots can perform physical tasks and communicate with humans through language or facial expressions. Compared to traditional robots, humanoid robots exhibit significant advantages in human-machine interaction, environmental adaptation, and task versatility.

 

 

1.2 The Development of Humanoid Robots: From Concept to Industrialization

The concept of robots has existed for over a century, and research on humanoid robots began in the mid-20th century, experiencing a long development process from laboratory prototypes to the early stages of industrialization. The earliest use of the term "robot" comes from Czech writer Karel Čapek's play R.U.R. (Rossum's Universal Robots), meaning machine slaves that serve humanity. The mass production of industrial robots began in the 1960s, with the "UNIMATE" robotic arm launched by American company Unimation, which opened the era of commercial industrial robots.

 

The research and development of humanoid robots began in Japan and gradually entered the stages of systematization and high dynamics:

 

Early Exploration Stage (Around the 1970s): In 1973, Professor Ichiro Kato of Waseda University in Japan developed the world's first humanoid robot, WABOT-1, and its WL-5 bipedal walking mechanism laid the foundation for humanoid robots.

 

Technology Integration Stage (1980s-1990s): In 1986, Honda started research on humanoid robot ASIMO, and in 2000, the first-generation ASIMO model was released, marking the entry of humanoid robots into a highly integrated technological stage.

 

Dynamic Performance Breakthrough Stage (2000-2020): In 2016, Boston Dynamics of the United States released the bipedal robot Atlas, which, with its powerful balancing ability and obstacle-crossing performance, reached new heights in dynamic movement and task execution in dangerous environments.

 

Early Industrialization Stage (2020-present): In 2022, Tesla launched the humanoid robot prototype Optimus, showcasing highly integrated artificial intelligence and motor drive technology at Tesla AI Day. The 2023 version of Optimus is capable of object classification and precise balancing, signaling that humanoid robots are gradually moving toward practical application.

 

1.3 Deep Integration of Humanoid Robots and Motor Technology

The continuous evolution of humanoid robots is inseparable from the support of motor technology. As the core component of robot joint drives, motors not only determine the robot's motion performance but also affect its flexibility and durability. With their high precision, low energy consumption, and reliability, motor drives have gradually become the most commonly used power solution for humanoid robots. Meanwhile, coreless motors, with advantages like lightweight, high efficiency, and low inertia, are providing crucial technological support for the rapid development of humanoid robots.

 

In the future, with further breakthroughs in technology, humanoid robots will become more widely used in various life scenarios, injecting new vitality into global economic and social development. This makes the motor market, especially the coreless motor market, a new and highly anticipated blue ocean.

 

1.4 Humanoid Robot Structure: Analysis of Key Components

The key structure of humanoid robots can be divided into three main modules: actuators, controllers, and sensors. Major components like motors, reducers, and sensors determine the robot's performance. Below is a detailed analysis of these components:

 

1.4.1 Motor

The motor is the core of humanoid robot motion execution, including servo motors, stepper motors, torque motors, and spherical motors, among others. Among them, torque motors are considered ideal for humanoid robot joints with low-speed, high-torque demands due to their ability to provide high torque at medium and low speeds. However, their research and production difficulty is relatively high, requiring breakthroughs in technological bottlenecks.

 

1.4.2 Reducer

Harmonic reducers are widely recognized for their compact structure, high transmission ratio, and superior precision, making them a common choice for robot joint components. However, their durability and lifespan still have room for improvement.

 

1.4.3 Sensor

Sensors play a critical role in robots, particularly torque sensors, which are an essential part of joint design. These sensors, in combination with motors and reducers, form the joint assembly and provide precise motion control and force feedback.

 

1.4.4 Upper Limb Drive Method

The upper limbs mostly use ball screw designs, which convert the reciprocating motion of the balls into linear motion of the screw. Compared to belt or chain drives, ball screws have less friction, lower operation and maintenance costs, and higher precision.

 

1.4.5 Lower Limb Drive Method

Planetary roller screws, known for their resistance to external force impact and long service life, have become the main choice for lower limb drives, especially suitable for handling complex gait control needs.

 

1.4.6 Hand Joint

Hand joints commonly use coreless motors. These motors have a simple design, lightweight, and are ideal drive components for finger movement, enabling finer control.

 

In addition, the bearing choices for linear and rotary joints include angular contact bearings, crossed roller bearings, and deep groove ball bearings. These components together ensure the robot's lightweight, precision, and reliability.

 

 

Intelligent Advantages of Motor Drive

Compared to hydraulic drives, motor drives exhibit particularly outstanding intelligent performance in motion control. For example, Tesla's humanoid robot adopts high-torque density servo motor technology, with its intelligent motion control far exceeding traditional hydraulic systems. This design not only allows real-time feedback of motion status to ensure control precision but also keeps costs relatively low, making it suitable for large-scale applications.

 

Performance Requirements for Servo Motors

As the core of robot actuators, servo motors need to meet the following performance requirements:

• Fast Responsiveness: Servo motors need to start and stop quickly to adapt to high-dynamic environments.
• High Starting Torque-to-Inertia Ratio: Servo motors should provide high starting torque while maintaining low rotational inertia.
• Continuous Control and Linear Characteristics: The motor speed needs to adjust continuously with changes in the control signal to ensure precise execution.
• Compact Design: Servo motors should be small in size and lightweight to fit into the robot's compact spatial layout.
• Durability and Overload Capability: Servo motors must withstand frequent forward and reverse rotations and acceleration/deceleration operations, and bear several times the rated load for short durations.

These characteristics make servo motors indispensable in the field of robotics, laying the foundation for higher intelligence and stability in robots.

 

Continue reading: The heart of robot motion - the decisive role of motors in precision - Part 2