China’s Robotics Core Components Market: Reducers, Lead Screws, and Motors – The Billion-Dollar Opportunity

If you are looking for the real money in the humanoid robot industry, do not stare at the final assembly line. Look at what goes inside.

The three core component categories — reducers (减速器), lead screws (丝杠), and motors (电机) — together account for roughly 45% of a humanoid robot’s total bill of materials (BOM)[reference:0]. They also represent the highest technical barriers, the tightest supply constraints, and the most compelling investment opportunities in the entire robotics value chain.

This article breaks down each of these three critical segments — the technology, the market size, the key players, and what it means for global businesses looking to engage with China’s robotics supply chain.

1. Reducers (减速器) — The Joints That Make Movement Possible

Reducers are the components that convert a motor’s high-speed, low-torque rotation into the low-speed, high-torque motion that robots need to lift, grip, and walk. Without them, a robot’s joints would be weak, imprecise, and practically useless.

Market Size

Reducers account for approximately 15% of a humanoid robot’s total BOM cost[reference:1]. At mass production scale, each Optimus-class robot uses about 22 reducers across its joints【30†L30】. At a unit price of roughly RMB 600 ($88) at scale, the per-robot reducer value is approximately RMB 13,200 ($1,940).

Technology: Harmonic Dominates, But Alternatives Are Emerging

Tesla’s Optimus currently uses harmonic reducers as the dominant solution for most joints, particularly in the upper body and wrists where precision and compactness are paramount【25†L25】. Harmonic reducers offer high reduction ratios, zero backlash, and exceptional precision in a lightweight, compact package.

However, the industry is also exploring alternatives. Planetary reducers and cycloidal/RV reducers are gaining traction for lower-body joints — hips, knees, and ankles — where higher load capacity and impact resistance are more important than absolute precision【25†L25】.

Key Players: Leaderdrive Leads the Charge

The global harmonic reducer market has long been dominated by Japan’s Harmonic Drive Systems (HDSI). But that is changing — and fast.

Notably, Leaderdrive and Japan’s HDSI together hold over 63% of the global revenue market share in harmonic reducers[reference:9] — a duopoly that is increasingly being challenged by Chinese manufacturers’ cost advantages and expanding production capacity.

2. Lead Screws (丝杠) — The Heart of Linear Actuators

If reducers are the joints, lead screws are the muscle fibers. They convert rotational motion into linear motion — the pushing and pulling that allows a robot to lift, reach, and grip.

Lead screws account for approximately 18% of a humanoid robot’s BOM cost, making them the single most valuable component category after actuators themselves[reference:10].

Market Size

Each Optimus-class robot uses about 16 planetary roller screws for high-torque areas (hips, knees, shoulders) and 44 micro ball screws for the dexterous hand【30†L30】. At mass-production prices — roughly RMB 800 ($118) per planetary roller screw and RMB 100 ($15) per micro ball screw — the per-robot lead screw value is approximately RMB 17,200 ($2,530).

Technology: Planetary Roller Screws Are the Gold Standard

The planetary roller screw is the undisputed champion for high-load linear actuation. Compared to ball screws, planetary roller screws offer:

• 3× higher load capacity — more contact points distribute force more evenly【24†L24】
• 10–15× longer service life — critical for industrial deployment【24†L24】
• Higher precision — with lead accuracy down to C3 grade[reference:11]
• Better shock resistance — essential for walking and heavy lifting【24†L24】

This segment was historically dominated by European and Japanese players like THK (Japan) and Schaeffler (Germany). But Chinese manufacturers are rapidly closing the gap — and doing so at 30–40% lower cost[reference:12].

Key Players: A Two-Horse Race with Rising Challengers

Other notable players include 贝特科技 (Bete Technology), which also produces planetary roller screws for Tesla[reference:22], and 诺仕机器人 (NOUSBOT), which recently completed a nearly RMB 100 million Series A+ financing round[reference:23].

3. Motors (电机) — The Power Source

Motors are the prime movers — they convert electrical energy into mechanical energy. In humanoid robots, two motor types dominate:

• Frameless torque motors for the large joints (shoulders, hips, knees, waist)
• Coreless (hollow-cup) motors for the dexterous hand

Motors account for approximately 12% of the BOM cost[reference:24].

Market Size

At 1 million units, the motor market reaches RMB 15.8 billion ($2.3 billion) — with frameless torque motors contributing RMB 11.4 billion and coreless motors contributing RMB 4.4 billion【26†L26】.

Frameless Torque Motors: The Joint Workhorses

Frameless torque motors are directly integrated into the robot’s joints — there is no separate housing or coupling, which saves weight and space while improving efficiency. They are used in shoulders, elbows, wrists, hips, knees, and ankles.

According to industry data, nearly 20 Chinese motor makers are racing to capture share in this fast-growing segment[reference:25]. Leadshine Technology delivered over 120,000 frameless torque motor units in 2025[reference:26]. Step Electronics sold approximately 83,000 units in 2025 and continued its momentum with 35,000 units in Q1 2026 — growing 246% year-over-year[reference:27].

Key domestic players in frameless torque motors include 汇川技术 (Inovance Technology), which has completed development of core components including frameless torque motors and low-voltage high-power drives[reference:28], Kollmorgen, Aerospace Electric, Haozhi Electromechanical, and Micro Precision Motor[reference:29].

Coreless Motors: The Key to the Dexterous Hand

The dexterous hand is one of the most challenging parts of a humanoid robot — and it is also one of the most valuable. Each Optimus hand requires approximately 10-12 coreless motors to drive its 11 degrees of freedom[reference:30][reference:31]. With two hands, that is 20-24 motors per robot just for the hands.

According to industry analysis, 1 million humanoid robots would correspond to a RMB 10 billion ($1.5 billion) market for dexterous hand motors alone[reference:37].

4. The Big Picture: A $7.3 Billion Opportunity at 1 Million Units

When you add it all up, the three core component categories — reducers, lead screws, and motors — represent a combined incremental market of approximately RMB 50 billion ($7.3 billion) at 1 million units. At 10 million units, that figure grows to RMB 500 billion ($73 billion).

And this is just the beginning. These figures do not include sensors, structural components, or the fast-growing market for executors (actuator assemblies), which represent an additional ~35% of the BOM.

5. Practical Guide: How to Verify These Chinese Suppliers

For global businesses — whether you are an investor, a procurement professional, or a potential partner — the opportunity is clear. But so are the risks.

This is where ChinaBizInsight comes in. We help global businesses know their Chinese partners through authoritative, verified information.

Our services include:

• Official Enterprise Credit Reports — Directly from China’s National Enterprise Credit Information Publicity System, with official watermarks and government logos.
• Customized Credit Decision Reports — Standard, Professional, and Financial & Tax versions that integrate data from multiple authoritative sources.
• Executive Risk Reports — Deep-dive reports on directors, supervisors, and senior management.
• Hong Kong, Macau, and Taiwan Company Searches — Including incorporation certificates, business registration certificates, and credit reports.
• Apostille & Notarization Services — To ensure your Chinese company documents are legally recognized in your home country.
• Intellectual Property Searches — Trademark, patent, and copyright verification.

👉 Learn more about our China company verification services →

6. Conclusion: The Window Is Open — But Don’t Go In Blind

China’s robotics core components market is undergoing a structural transformation. What was once a Japanese- and European-dominated landscape is now being reshaped by Chinese manufacturers offering comparable quality at 30–60% lower prices[reference:38][reference:39].

For global businesses, this represents a once-in-a-decade opportunity to secure supply chain partners, capture cost advantages, and participate in the fastest-growing segment of the robotics industry.

But opportunity comes with responsibility. The Chinese corporate landscape can be challenging to navigate — especially for foreign entities. Due diligence is not optional; it is essential.