A Novel Gearbox Optimized for Humanoids
Thin and Lighweight
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Single stage structure
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Available with FRP material
Precise and Strong
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< 5 arcmin
Mass Producible
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Simplified machining process
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Automated assembly
Ideal Reduction Ratio
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Optimized in between 1:15 ~ 1:30
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Suitable for humanoids and other service robots
Introduction
Elacloid Drive is a speed reducer (gearbox) that utilizes planocentric motion mechanics. Invented by Justin H. KANG, Ph.D. in 2014, it serves as a cost-effective alternative to expensive conventional strain wave (Harmonic Drive) gearboxes. Initially commercialized by MINTROBOT, it has since been transferred to Meta Actuator with significant production improvements. The key advantage of Elacloid Drive is its ability to deliver middle-range reduction ratios—bridging the gap between conventional planetary gearboxes and harmonic drives—in a single-stage mechanism. This is achieved using various materials through a simplified manufacturing process. These features make it ideal for service robots, offering both mass-producibility and flexible material selection that reduces weight and manufacturing costs.
Principle
Elacloid Drive leverages elastic deformation among the gearbox's friction components to eliminate negative effects caused by machining errors such as backlash and abnormal friction. Rather than increasing machining costs to achieve precise shapes, it utilizes elastic deformation created by specific shapes and materials to mitigate performance issues caused by geometrical errors. This approach reduces overall manufacturing costs while increasing productivity.
Problems : Limitation of Precision Machining
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Miniaturization is difficult due to tight tolerance requirements and backlash sensitivity
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Tolerance precision cannot be increased proportionally as size decreases
Elastic Tooth Technology: Enabling Lightweight, Precise, and Scalable Cycloidal Drives
Key solution for miniaturizing conventional cycloid drives with our authentic patented structure
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Elastic teeth eliminate clearance and friction problems during cycloid drive miniaturization
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Preserves high precision and minimal backlash even in smaller gearbox dimensions
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Our design uses minimized carbon steel along with other materials such as FRP, allowing for lightweight and durable structures with greater design flexibility
History of Development
10-Year Development Timeline: From Concept to Commercialization
1. Verification of the Principle (2015 ~ 2019)
During this period, research focused on applying the gearbox as a substitute for existing strain wave gearboxes in industrial robots. The team successfully developed the design and manufacturing process to achieve zero-backlash with strong stiffness, completing the proof of concept. However, mass production proved challenging due to dependency on skilled machining craftsmen, which diminished the product's value as an alternative to strain wave gearboxes.
2. Develope Speciality and Prepare for Mass Production (2020 ~ 2025)
During this period, the team refined the gearbox's unique capabilities. Rather than simply matching strain wave gearboxes for industrial robots, they enhanced its productivity and reduced weight specifically for service robots. By incorporating various composite materials with its authentic structure, they achieved optimized performance within its distinctive operational range.
Core Technologies
1. Minimizing Friction: Key to achieving a simple and lightweight structure
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In conventional cycloid drives, the outer disc contacts multiple pins, creating sliding friction, high internal loads, and unbalanced stress
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Our design uses only a single point of contact at any moment—converting sliding friction into rolling friction even with FRP materials
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This drastically reduces wear and heat, enabling longer service life and higher efficiency
2. Optimized Manufacturing Process: Key to reducing cost
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Traditional cycloid gearboxes require complex, multi-step machining and skilled labor, limiting scalability and cost reduction
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Our gearbox uses a streamlined manufacturing process centered on injection molding and automation
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By eliminating dependency on craftsmanship, we enable consistent mass production at lower cost
Patents
During the development of our core technologies, we have secured multiple international patents. Through continuous performance enhancements, we are steadily expanding our intellectual property portfolio.