Humanoid Robot Industry Chain And Prospect Analysis

1. Breakdown and value distribution of humanoid robots
1. Disassembly of humanoid robot

At the first Tesla AI Day in August 2021, Tesla released a concept drawing of its first humanoid robot "Optimus". The humanoid robot is 5 feet 8 inches tall, weighs 125 pounds, and has 45 lb. carrying capacity and a deadlift capacity of 150 lbs., which will be controlled through smart algorithms similar to those used in electric vehicles. A prototype will be launched in February 2022, and a new generation of nearly complete humanoid robot will be unveiled on AI Day on September 30, 2022. It will be unveiled at the World Artificial Intelligence Conference in July 2023.

The latest generation of Optimus released by Tesla has 28 joints (14 rotary actuators + 14 linear actuators) in the mechanical part of the body, and the 2 dexterous hands have a total of 12 joints (6 actuators * 2). Tesla's humanoid robot's dexterous hands are designed to mimic human hands and have adaptive grasping capabilities. The hand structure has five fingers and multiple joints. The thumb uses dual motors to drive bending and side swinging, and the other four fingers have one motor each. It has a total of 6 actuators, 11 degrees of freedom, a load of 20 pounds, the ability to adapt to the grasping angle, the ability to use tools, and the ability to accurately grasp small objects. The 28 actuators on the Tesla humanoid robot are distributed on the shoulders (6), elbows (2), wrists (6), torso (2), hips (6), knees ( 2 pcs), ankle (4 pcs).

Tesla Optimus's rotating joint solution: frameless motor + harmonic reducer + torque sensor + position sensor + bearings (angular contact ball bearings + crossed cylindrical roller bearings) + encoder. Tesla simultaneously demonstrated its actuator product portfolio, which includes three rotary reducers with different torques, respectively 20Nm/110Nm/180Nm. Whole body distribution: 6 on shoulders, 2 on wrists, 4 on hips, and 2 on trunk.

Tesla Optimus' linear joint solution: frameless motor + planetary roller screw + torque sensor + position sensor + bearing. Tesla simultaneously demonstrated its actuator product portfolio, which includes three linear actuators with different torques, with torques of 500N/3900N/8000N. Whole body distribution: 2 elbows, 4 wrists, 2 hips, 2 knees, and 4 ankles.

2. Value distribution of the main parts of humanoid robots

Referring to Tesla Optimus, the value of the humanoid robot is mainly distributed in the FSD system, AI chip, actuator, and dexterous hand limb skeleton: FSD/AI chip: Tesla's core competitiveness, the value of a single machine is about 50,000 yuan, and the cost Accounting for approximately 26.5%; Rotary actuator: assembly products will be supplied by third parties, including harmonic reducers (or new harmonic-like reducers), frameless torque motors, torque sensors, encoders, bearings and other major Part, the cost accounts for about 23%; linear actuator: the assembly product will be supplied by a third party, including planetary roller screw, frameless torque motor, torque sensor, encoder, bearing and other major parts, the cost accounts for about 28%; dexterous hand: including coreless motor, planetary gearbox, sensor, ball screw, etc., accounting for approximately 7% of the cost; limb skeleton: mechanical structural parts, accounting for approximately 13% of the cost. Among the non-assembly parts supplied by third parties, frameless torque motors (14.84%), planetary roller screws (14.84%), harmonic reducers (7.42%), torque sensors (7.42%), encoders (4.45 %), coreless motors (3.82%) account for a larger proportion. 2. Analysis of the main links of humanoid robots

1. Reducer: Technical barriers are high, domestic substitution is accelerating

Robot reducers are mainly divided into two categories: RV reducers and harmonic reducers. The harmonic reducer has the advantages of large single-stage transmission ratio, small size, low mass, and high motion accuracy. It can work normally in confined spaces and medium radiation conditions, and is more suitable for light-load precision deceleration fields, such as humanoid robots, etc. . Compared with harmonic reducers, RV reducers have the advantages of large transmission ratio range, relatively stable accuracy, high fatigue strength, etc., as well as higher rigidity and torque carrying capacity. They are mainly suitable for heavy-load parts such as robot arms and machine bases. .

The difficulties of harmonic reducers mainly lie in tooth design, materials, processing equipment, technology and consistency. Technical difficulties specifically include: Tooth shape design: Since the transmission principle of the harmonic reducer is the meshing motion between two gears, and the flexspline is constantly deforming, the height, width, shape and other designs of the gears have a greater impact on the deceleration performance. Influence. Material: The flexspline continuously deforms and transmits torque, which poses great challenges to the consistency, load, accuracy, and fatigue life of the material. Ordinary metals and alloys are difficult to meet the requirements. Processing equipment: The flexspline is very thin, with a thickness of about 100 μm. The processing and cutting requirements are high. High-precision CNC grinders and gear hobbing machines need to be imported, and Japanese high-precision machine tools have restrictions on my country. Processing technology: The processing and cutting of flex splines are highly demanding, and some processes still rely on the experience accumulation of employees. Consistency: In large-scale mass production, it is very difficult to reduce the defective rate and maintain product consistency. Compared with harmonic reducers, RV reducers have a more complex structure and have stricter requirements for processing accuracy and technology. The technical difficulties are specifically: Processing accuracy: The structure is complex. In actual working conditions, the RV reducer needs to be repeatedly and accurately positioned, which is equivalent to continuous starting and braking to maintain accuracy without attenuation. If the accuracy is low, it will cause wear and tear of the product. Processing technology: The close cooperation of various processes, including tooth surface heat treatment, processing accuracy, part symmetry, grouping technology, and assembly accuracy. The final assembly tolerances of these processes will cause wear and life of the product. Consistency: As precision components, it is not difficult for a single product to achieve high performance, but it is a great challenge for large-scale mass-produced products to meet standard performance.

The import monopoly of reducers is expected to be broken, and domestic substitution is underway. The global robot reducer market is highly concentrated, with Japanese manufacturers occupying most of the market share. In 2021, Nabtesco occupied 53% of China's RV reducer market share, and Hamon Naco occupied 35.5% of China's harmonic reducer market share. However, China has now regarded breakthroughs in key core technologies of robots as an important project, and domestic manufacturers have overcome some of the problems in key core components such as reducers, controllers, and servo systems. The export volume of China's RV reducers has shown an overall upward trend, while the import volume has generally shown a downward trend. The trend of localization of RV reducers has emerged. In recent years, domestic harmonic manufacturers have gradually entered the supply chain of downstream customers, and the market share of Chinese brands has increased year by year. The unit price of imported precision reducers, such as the products of Japan's Hamonoko Company, is usually between 3,000 and 4,000 yuan. The unit price of domestic precision reducers is 30% to 50% of the price, which has a price advantage.

2. Lead screw: The technical barriers are very high, and there is a lot of room for domestic substitution.

The screw is an ideal product for converting rotary motion into linear motion, or converting linear motion into rotary motion. Common screw products include sliding screws, ball screws, planetary roller screws, etc. Ball screw is a commonly used transmission element in industrial precision machinery. Its main structure includes three parts: ball screw, ball nut and ball. The core transmission principle is to convert rotational motion into linear motion and convert sliding friction into rolling friction. When the screw rotates relative to the nut, the rotating surface of the screw pushes the nut to move axially through the cyclic rolling of the balls, turning the rotation into linear motion; the rolling of the balls causes the sliding friction between the screw and the nut to change into the sliding friction between the balls, the screw, and the nut. The rolling friction between them turns sliding into rolling, greatly improving transmission efficiency. Planetary roller screws are a high-precision branch of the new generation of threaded screws, with strong comprehensive performance and broad application prospects. The planetary roller screw generates line contact rolling friction through meshing rollers, which greatly increases the contact surface and stress surface during the screw transmission process. Compared with the previous ball screws used for precision transmission, the transmission efficiency is not significantly lost. At the same time, it has the characteristics of high speed, high load, high stiffness, high range of lead, smaller size, lower noise, and easier maintenance and disassembly. It has been used in global high-precision fields such as aerospace, weapons and equipment, and nuclear power. It also has extensive application needs in civilian scenarios such as machine tools, automotive ABS systems, and petrochemical industries.

Ball screw: The ball screw was invented in 1874. In the 1930s, General Motors of the United States first applied ball screw components in automobile steering devices. In the 1940s, ball screw pairs were first used on CNC machine tools. , and has become an ideal feed element for CNC machine tools; with the development of machine tools and automation equipment, the research and production of ball screw pairs have been promoted. In the 1950s, many ball screw manufacturers began to appear in industrially developed countries, such as the British ROTAX , Japan NSK, etc. The development of ball screw pairs for CNC machine tools in our country started in the 1950s. In 1964, my country designed and developed the first set of ball screw pairs on its own. Since the country launched related projects in 2009, domestic companies such as Hanjiang Machine Tool and Shandong Bote Seiko and others have achieved many excellent results, but at present, my country still has room for improvement in high-performance products compared with the world's advanced companies. In the domestic market, the mid-to-high-end ball screw market is mainly occupied by German and Japanese companies, such as THK, International companies such as NSK and Rexroth can occupy 90% of the market share in the high-end market, while mainland Chinese companies are mainly active in the mid-range market, accounting for about 30% of the market share. The main reason is that our country's enterprises are small in scale, started late, and cannot reach a high level of precision in product quality.

Planetary roller screw: In 1942, Swedish Carl Bruno Strandgren first applied for a patent for a recirculating planetary roller screw. In 1954, he applied for a patent for a standard and reverse planetary roller screw. In 1986, William J. Roantree Invented the differential planetary roller screw, and then Oliver Saari invented the bearing ring planetary roller screw. In 1970, Switzerland's Rollvis Company began to develop planetary roller screws. Sweden's SKF also developed planetary roller screws. Moog in the United States, Ortlieb in Germany and Power Jacks in the United Kingdom all have their own mature planetary roller screws. Products; Exlar of the United States and Rexroth of Germany both use planetary roller screws in their respective electromechanical actuators. In 2022, Japanese and European roller screw companies will account for as much as 90% of the Chinese market. According to data from the Guanyan Report Network, the top four manufacturers in my country's planetary roller screw market supply in 2022 are Rollvis (Switzerland), GSA (Switzerland), Ewellix (Sweden) and Rexroth (Germany), with market shares of 27 %, 26%, 13%, 12%. Because Chinese enterprises started late in this industry, their competitive strength lags far behind that of enterprises in foreign industrially developed countries.