The “Sensory Nerve” of Robot Joints

In intelligent equipment such as humanoid robots and industrial manipulators, the motion accuracy of each joint directly determines the overall performance of the machine. Inside each joint works a critical but often overlooked component – the magnetic encoder code disc. Like a “sensory nerve,” it continuously senses the rotor’s angle and position, converting mechanical motion into electrical signals and providing precise feedback to the control system.

Magnetic encoders operate on a non-contact principle. They use Hall effect or magnetoresistive sensors to detect magnetic field changes generated by the rotating magnetic code disc, thereby outputting high-precision angle information. Compared with traditional optical encoders, magnetic encoders have a simpler structure, requiring no light source or complex optical components. They excel in harsh environments – resisting vibration, corrosion, and oil contamination – while offering inherent advantages in size, weight, and reliability. With the explosive growth of humanoid robotics and industrial automation, high-performance magnetic encoders are facing unprecedented opportunities.

Industry Pain Points: Long Customization Cycles, Space Constraints, High Costs

Despite strong market demand for magnetic encoders, the code disc customization process still faces a series of “bottleneck” problems that hinder the upgrade of domestic robot joints.

1. Long mold opening cycles, slow response

In traditional code disc customization, customers must pay high mold fees and wait weeks or even months to receive samples. For robot manufacturers pursuing rapid iteration, this slow response often means missing market windows.

2. Low customization efficiency

Parameters such as the number of pole pairs, dimensions, and mounting interfaces of magnetic encoder code discs must closely match the design of the motor and joint module. However, most suppliers lack a flexible customization process, making it difficult to quickly adjust designs and processes according to customer needs, thus prolonging project timelines.

3. Difficult installation in confined spaces

The internal space of a robot joint is extremely limited – motors, reducers, sensors, driver boards, and many other components must be tightly integrated. How to arrange the code disc and readhead within such a small space while ensuring signal stability and accuracy is a core challenge faced by many customers during the structural design phase.

4. Dependence on imported high-precision code discs, high cost pressure

For a long time, domestic high-precision magnetic encoder code discs have been unable to meet accuracy requirements, forcing many 19 bit or 20 bit high-precision magnetic encoders to be imported from Europe. These are not only expensive but also have long delivery lead times. In 2024, China’s magnetic encoder market size reached approximately RMB 1.114 billion. Although import substitution is accelerating, the self sufficiency of high-performance products still has a long way to go.

SDM: Four Core Strengths Solving Industry Challenges

In response to the above pain points, SDM has deeply engaged in the R&D and manufacturing of magnetic encoder code discs. With four core strengths, SDM provides a one stop high performance magnetic code disc solution to empower the upgrade of domestic robot joints.

I. Full coverage of specifications, eliminating long mold opening cycles

SDM has established a complete portfolio of standard products, covering mainstream sizes and pole pairs. Standard items are available from stock for immediate delivery – select and use directly, greatly shortening delivery cycles and freeing customers from long mold opening waits.

II. Fast sampling to seize R&D opportunities

SDM has streamlined the entire customization development chain. Samples for new product support can be delivered in as fast as 7 to 15 days. In the fiercely competitive robot market, time is opportunity. This capability effectively compresses customers’ R&D cycles and helps integrators seize market windows.

III. Deep collaboration for integrated structural optimization

SDM’s technical team deeply engages in customers’ solution design, customizing integrated code disc and structural part solutions according to application needs. Whether embedding the code disc inside the motor to reduce axial size or adapting to special mounting geometries, SDM provides targeted solutions that fundamentally solve installation difficulties in confined spaces.

IV. Ultra-high cost performance, first choice for domestic cost reduction

Leveraging in house processes and mass production capabilities, SDM achieves an extremely competitive cost performance ratio while ensuring multi pole precision magnetization and high accuracy magnetic field performance. Customers can effectively reduce the overall cost of joint modules without sacrificing accuracy, accelerating the mass production of domestic robots.

Conclusion

From standard product selection to deep customization, from fast sampling to structural co optimization, SDM is using its comprehensive technical strength and agile responsiveness to support domestic robot joints in both precision improvement and cost optimization. We welcome all integrators and joint module manufacturers to select and cooperate with us, jointly advancing the domestic robotics industry to new heights.