2 DisAssemble the humanoid robot core hardware

2.1 Reducer

Reducer is an industrial basic component, is a more precise mechanical transmission device. The reducer uses the meshing of the gear to change the motor speed, torque and load capacity, which can be used to achieve precise control. Can be widely used in machine people, CNC machine tools, photovoltaic equipment, medical equipment and other industries.

2.1.1 Reducer is the core component of robot

Robot core parts R & D and manufacturing mainly include servo system, reducer and controller accounting for about 70% of the cost of industrial robots. The reducer, servo system (including servo motor and servo drive) and controller directly determine the performance, reliability and load capacity of industrial robots, and play a crucial role in the robot. Among them, the highest cost ratio is the reducer, accounting for 35%.

The human body is able to move freely because of the “bone joint” structure, most of the bone joints through the cartilage to protect the bone from wear. Joints are located in various parts of the human body, which can make the action more coordinated, and through joint activities, the human body can be more dexterous and more “accurate” when completing complex actions. The “movement” of industrial robots is mainly completed by three main components: servo motor, reducer and controller. The servo motor is responsible for driving, and the operation of the servo motor is characterized by fast speed and small torque, while the joint requires slow speed and large torque. The reducer is a transmission component composed of a number of gears, using gear mesh to change the system output speed, torque and load capacity. It can accurately reduce the speed of the servo motor to the speed required for various parts of the industrial robot, improve the positioning accuracy, output greater torque, and make the robot movement more accurate. Generally speaking, the reducer can improve the positioning accuracy and repeated positioning accuracy of the machine.

Another role of the reducer in industrial robots is to transmit greater torque. When the load is large, it is not cost-effective to blindly increase the power of the servo motor, and the output torque can be increased by the reducer in the appropriate speed range. Reducers can be divided into general purpose, special, precision reducers, which are mainly used in the robot industry for precision reducers. General reducer generally refers to the gear reducer, worm turbine reducer and planetary reducer, mainly small and medium-sized, widely used in various industries; Special retarders are generally large and extra-large, mostly for industry-specific retarders, such as automotive retarders, photovoltaic retarders, and wind power retarders.

2711P-K10C4A2

Planetary reducer used to be mainly used in the industrial field, the current precision planetary reducer used in the rectangular coordinate industrial machine, can also be used in the humanoid robot small joints (such as fingers) or motion joints (such as legs) collar field. Precision planetary reducer in the operation process is similar to a sun wheel has a number of planetary wheels around, so its small size, light weight, compared with other reducer start more stable, and rigidity, accuracy and torque high. It is characterized by compact structure, low speed and high torque, cheap price but low deceleration ratio. In general, it is still difficult to apply the traveling star reducer to high-tech robots. The precision reducer is mainly micro and small, widely used in industrial robots, machine tools, semiconductors, aerospace and other high-precision scenes, especially used in robots, there are mainly two categories: harmonic reducer and RV reducer.

The harmonic reducer has the advantages of large single-stage transmission ratio, small volume, small mass, high motion accuracy and can work normally in closed space and medium radiation conditions. And compared with the general reducer, when the output torque is the same, the volume of the harmonic reducer can be reduced by 2/3, and the weight can be reduced by 1/2, which makes it have a strong advantage in the robot forearm, wrist, hand and other parts. The RV reducer has a large transmission ratio range, relatively stable accuracy, high fatigue strength, and higher rigidity and torque carrying capacity, and has advantages in heavy load parts such as robot arm and frame. However, the load of the harmonic reducer is light, allowing the torque load to be within 1,500N·m, so it limits the possibility of expanding to the heavy load part. The RV reducer allows a torque load of up to 8,000N·m, and its heavy weight and large size characteristics also make it impossible to develop into a lightweight and flexible light load field. The two apply to different fields and cannot replace each other. The characteristics of harmonic reducer such as small size, light weight and large transmission ratio make it widely used in light load fields such as humanoid robots. The price of domestic harmonic reducer has been declining year by year, at present, it is 1000-3000 yuan/piece, and the future is expected to be reduced to 500-1000 yuan/piece in the mass production of humanoid robots. According to the green harmonic prospectus, in 2018 and 2019, the unit price of the company’s harmonic reducer was 1,885 yuan/piece and 1,632 yuan/piece respectively, and the subsequent company did not disclose the income of the harmonic reducer separately. On the premise of technology maturity in recent years to reduce costs, we expect the unit price of the domestic harmonic reducer to be 1,500 yuan/piece. If the humanoid robot is mass-produced, the price is expected to drop to 500-1000 yuan/piece.

2.1.2 Reducer market ushered in the “golden Age”

From the perspective of demand, the new robot demand is the main driving force for the development of the reducer industry. In addition, the reducer itself has a rated service life and needs to be replaced regularly, that is, the replacement of the stock market is also one of the demand side. The working life of industrial robots is generally 8-10 years, during which the reducer is used as a transmission and load-bearing part, wear is inevitable, and its service life is usually about two years. Therefore, the current maintenance of industrial robots also requires a large number of reducer replacements. GGII data show that the total demand for industrial robot reducer in China in 2021 is 931,100 units, an increase of 78.06%. Among them, the incremental demand was 824,100 units, an increase of 95.05%; The stock replacement volume was 107,000 units, an increase of 6.57%. With the acceleration of the AI process, machine replacement will benefit from it, and the certainty of the growth of the reducer market is expected to be further enhanced in the next few years, and the total market demand is expected to exceed 2.7 million units by 2026.