Elon Musk's Plan to Build One Million Robots: How Many Motors, Reducers, and Lead Screws Are Made in China?

This time, Elon Musk is going to learn from the Chinese manufacturing industry.

In January 2026, Tesla completed the supply chain factory audit for the third - generation Optimus robot.

In March, Elon Musk gave clear mass - production guidelines at Tesla's all - staff meeting. The goal for 2026 is to produce 50,000 to 150,000 Optimus units, and the goal for 2030 is 50 million units.

An even more radical figure, often mentioned by Musk, is to produce 100 million units in the next year.

What does 100 million units mean? The annual global shipment of smartphones is about 1.2 billion units.

At the very foundation of this huge number - how many components of an Optimus robot come from China?

First, disassemble an Optimus

To understand the opportunities for Chinese companies, we first need to understand the bill of materials (BOM) of an Optimus robot.

According to the information disclosed by Tesla in 2025, the BOM cost target for an Optimus robot is to be reduced from about $43,000 in the small - batch production stage to less than $20,000 in the mass - production stage.

This $20,000 can be roughly divided into five parts:

▍Actuators: Account for about 35% of the cost

Actuators are the "joints" of the robot. They are divided into two types: rotary actuators and linear actuators, which are distributed in key parts such as the shoulders, elbows, wrists, hips, knees, and ankles.

An Optimus robot needs about 28 actuators. This is the largest part of the cost.

▍Reducers: Account for about 15% of the cost

The function of the reducer is to convert the high - speed, low - torque of the motor into the low - speed, high - torque required by the robot.

The most commonly used reducer in rotary joints is the harmonic reducer, while the planetary reducer is used in heavy - load joints of the lower limbs.

▍Lead screws: Account for about 18% of the cost

The lead screw is the heart of the linear actuator. In parts such as the hips, knees, and ankles that need to bear large torques, "reverse planetary roller screws" are used.

This segment has long been monopolized by European, American, and Japanese companies.

▍Motors: Account for about 12% of the cost

There are two key types of motors on the robot. Frameless torque motors are used for large joints, and coreless motors are used for dexterous hands.

A dexterous hand needs about 20 coreless motors.

▍Sensors and others: Account for about 20% of the cost

This includes six - axis force/torque sensors, tactile sensors, IMUs, vision sensors, as well as wiring harnesses, structural parts, batteries, etc.

▸ Optimus BOM target cost: About $20,000 per unit in the mass - production stage (disclosed by Tesla in 2026)

▸ Number of actuators per unit: About 28 (rotary + linear)

▸ Number of coreless motors per unit: About 20 (for dexterous hands)

▸ Number of reverse planetary roller screws per unit: About 14

▸ Production capacity target: 50,000 - 150,000 units in 2026, 50 million units in 2030 (guided by Musk at the all - staff meeting in March 2026)

One robot, 28 joints, 20 coreless motors, and 14 roller screws.

Chinese companies: Three main supply chains

According to the industrial chain research of several securities firms such as CITIC, Kaiyuan, and Guotai Junan, three main supply chains have emerged in the Chinese supply chain of Optimus:

The actuator assembly group, the precision transmission group, and the motor and sensor group.

▍The first group: Actuator assembly

This is the supply chain with the largest order amount and the highest certainty.

Top Group - Positioned as a Tier 0.5 supplier for Tesla's Optimus, it undertakes the assembly of linear/rotary actuators. According to public research information, Tesla's business accounts for 35% to 40% of Top Group's total revenue. Its factory in Mexico has been put into production, and the production capacity target for the second quarter of 2026 is 300,000 sets.

Sanhua Intelligent Controls - One of the core suppliers of joint module assemblies. In October 2025, Musk placed an order worth $685 million (about 5 billion RMB) with Sanhua, and the delivery from the Mexican factory will start in 2026.

These two are the most critical players "above the shoulders" in the Optimus supply chain.

▍The second group: Precision transmission

This supply chain focuses on two key components: reducers and lead screws.

Green Harmonic - The leading company in harmonic reducers. It has a domestic market share of over 60% and a global market share of over 35%. It has passed Tesla's supply chain verification and supplies exclusively to Tesla's Mexican factory. The company disclosed that the revenue related to humanoid robots in the first quarter of 2025 has increased to 30%.

Wuzhou New Spring - The main supplier of reverse planetary roller screws. Its main products are used in high - torque parts such as the hip and knee joints. Its factory in Thailand will be put into production in 2026. The stock price increased by 183% in 2025.

Double Ring Transmission - The core supplier of RV reducers, which indirectly enters the Optimus supply chain through Top Group and Sanhua.

There is also an unlisted company in this supply chain that needs to be mentioned separately - Xinjian Transmission.

On January 9, 2026, Hangzhou Xinjian Electromechanical Transmission Co., Ltd. completed the filing for listing guidance with the Zhejiang Securities Regulatory Bureau, and CITIC Securities served as the guidance institution. Its core product - a production line with an annual output of 1 million planetary roller screws for humanoid robots - is regarded as the "hidden champion" in the Chinese supply chain of Optimus.

▍The third group: Motor and sensor

This supply chain is relatively fragmented but undertakes the most precise "end - perception" tasks of Optimus.

AMETEK - The core supplier of coreless motors. It ranks among the top three in the global market share, and the probability of being selected in 2026 is relatively high.

Zhaowei Electromechanical - The supplier of dexterous hand drive modules, with an integrated design of micro - motors, reduction boxes, and lead screws, showing obvious cost - performance advantages.

Coliy Sensor - The only domestic enterprise that has achieved mass production of six - axis force/torque sensors, and its products have entered the verification stage of Tesla's supply chain.

Inovance Technology - The supplier of servo motors, and also the upstream of domestic robot brands such as Ubtech and Unitree.

▸ Top Group: Tesla's business accounts for 35% to 40% of its revenue (disclosed by the company)

▸ Sanhua Intelligent Controls: Received a $685 million order from Tesla in October 2025

▸ Green Harmonic: The revenue from humanoid robots accounted for 30% in Q1 2025 (company announcement)

▸ Wuzhou New Spring: The stock price increased by 183% in 2025 (data from Eastmoney)

▸ Xinjian Transmission: Started IPO guidance in January 2026 (from the official website of the China Securities Regulatory Commission)

Three barriers: Why China?

Why can Chinese companies account for about 70% of the Optimus supply chain?

The answer lies in three barriers.

▍The first barrier: Process accumulation in the automotive supply chain

The core players in the Chinese Optimus supply chain - Top Group, Sanhua, Wuzhou New Spring, and Double Ring Transmission - are all familiar faces in Tesla's automotive supply chain.

The capabilities of precision manufacturing, cost control, and rapid iteration have been accumulated in the new energy vehicle industry chain over the past decade.

The processes are interconnected from the automotive to the robot industry.

▍The second barrier: Industrial clusters in the Yangtze River Delta

Tesla's supply chain in Asia and some European regions is almost entirely built by enterprises in the Yangtze River Delta of China.

In Zhejiang, Jiangsu, and Shanghai, a complete "one - hour industrial circle" has been established around Tesla's automotive projects. From motors, reducers to precision lead screws and structural parts, samples can be delivered within 24 hours at the fastest.

This cluster effect cannot be replicated in the short term in Mexico in the United States or Berlin in Europe.

▍The third barrier: Price advantage

It is almost impossible to reduce the cost of a robot to less than $20,000 without the Chinese supply chain.

The price of Green Harmonic's harmonic reducers is about 40% to 60% of that of similar products from Japan's Harmonic Drive. The price of Wuzhou New Spring's planetary roller screws is about 50% of that of Germany's Rollvis.

When Musk said at Tesla's all - staff meeting that "Optimus is the biggest single product in the future," he knew clearly that this future cannot be achieved without the Chinese supply chain.

Three risk points

The opportunities are great, but the risks are also significant.

First - The uncertainty of Tesla's mass - production schedule.

The range of 50,000 to 150,000 units given by Musk is actually quite wide. If the actual mass production in 2026 is only the lower limit of 50,000 units, the flexibility of the entire supply chain will be halved.

Second - The risk of high customer concentration.

Tesla's business already accounts for nearly 40% of Top Group's revenue, and the proportion of revenue from humanoid robots in Green Harmonic's robot business is also increasing rapidly. Once the pace of Tesla's orders slows down, the performance flexibility of these companies will shrink significantly.

Third - The squeeze from the localization of North American production capacity.

After Tesla's Mexican factory is fully put into production, local suppliers (such as Rollvis and Harmonic Drive's US factory) may compete for market share again. Chinese companies such as Top Group and Green Harmonic have already planned to build joint - venture factories in Mexico to deal with this variable.

The ceiling of orders is high, but the rope underfoot is not loose.

The next observation window

According to Tesla's current pace, there are three key observation nodes in the Optimus supply chain:

The first node: In the second quarter of 2026, a large - scale order - placing wave may start after Tesla's Optimus press conference.

The second node: In the fourth quarter of 2026, the first production line with an annual capacity of 100,000 units needs to complete the ramp - up. At that time, the actual delivery situation and pass rate of Chinese suppliers will become the trigger points for re - pricing the valuation.

The third node: In 2027, Tesla plans to open up the sales of Optimus. Once the sales to enterprises and consumers start, the valuation logic of the entire supply chain will shift from "order - driven" to "consumer - driven."

This is not just Tesla's supply chain, but the second overseas expansion of Chinese manufacturing.

In the past decade, Chinese manufacturing completed its first overseas expansion of the industrial chain through new energy vehicles.

Top Group, Sanhua, and Double Ring Transmission were all winners in that round.

Now, the same group of companies is using the same set of processes to enter the new field of robots.

The only difference is that last time they were involved in the automotive chassis, and this time it is the joints of robots.

And the joints are much more precise than the chassis.

Information sources

1. Eastmoney: In - depth analysis of Tesla's Optimus humanoid robot suppliers after the discontinuation of Model S/X (January 29, 2026)

2. 21st Century Business Herald: Xinjian Transmission starts IPO - The three giants of the T - chain gather in A - shares (January 12, 2026)

3. Sina Finance: The list of core suppliers in the first row of Tesla's Optimus (March 18, 2026)

4. Sina Technology: Musk placed a $685 million order with Sanhua (October 15, 2025)

5. Wall Street News: Goldman Sachs investigated Chinese robot supply chains such as Sanhua (November 2025)

6. Zhihu: The investment panorama of the trillion - level humanoid robot track in 2026 (November 22, 2025)

7. Eastmoney Fortune: The robot theme that may double in 2026 (January 3, 2026)