TesSurface-Flux Test for Robot Permanent-Magnet Rotor Motor

In highend manufacturing sectors including robots, newenergy vehicles, servo motors, windpower equipment and smarthome motors, permanentmagnet rotors act as the core power components of motors. The uniformity of surface magneticfield distribution, magneticpole accuracy and magnetic stability directly determine motor energy efficiency, noise level, torque stability and service life.

Traditional manual sampling inspection and singlepoint magneticfield measurement suffer from low accuracy, incomplete data coverage, low throughput and significant humaninduced errors. To address these pain points, Yidi Electronics has developed a customized dedicated surfaceflux test system for permanentmagnet rotors, meeting stringent requirements for modern mass production, quality inspection and precision R&D.

This customized equipment is supplied for a roboticmotor designandmanufacturing company, targeting frameless torque motors as the DeviceUnderTest (DUT). The customer put forward key requirements covering surfaceflux characteristics, harmonic content, waveform curve comparison and automatic motor loading for testing. By developing dedicated test software and implementing PLC control design, Yidi has fulfilled all technical specifications. Comprehensive requirements in four dimensions — accuracy, efficiency, automation and compatibility — are fully satisfied, and onsite delivery and commissioning have been successfully completed.

Yidi PermanentMagnet Rotor SurfaceFlux Test System is an allinone intelligent inspection equipment specially developed for permanentmagnet components such as permanentmagnet rotors, multipole magnetic rings and magnetic tiles. Integrating precision servo motion control, highaccuracy magneticfield sensing, 3D scanning acquisition and intelligent dataanalysis technologies, it can automatically complete fullarea scanning of rotor surface magnetic field, data acquisition, defect judgment and report generation. It serves as core standard equipment for R&D iteration, 100% productionline inspection and quality control in magneticmaterial and motormanufacturing enterprises.

• Equipped with high‑precision Hall sensor modules and closed‑loop servo positioning system, this unit features ±0.02 mm positioning accuracy, 0.1 mm minimum spatial resolution and 0.1 mm max rotational concentricity. It captures minor rotor‑surface magnetic‑field differences, eliminating typical single‑point measurement flaws such as incomplete data, local demagnetization, uneven magnetic fields and magnetic‑pole offset. Accurate identification of micro‑scale magnetic defects provides solid data for product quality evaluation.


• All processes — sample positioning, 3‑axis scanning, magnetic‑field capture, data calculation, pass‑fail evaluation and data storage — execute automatically, no manual operation required. With a 10 s‑per‑revolution typical test cycle, it finishes full‑area rotor inspection within seconds for high‑speed mass‑production compatibility. It auto‑locates zero‑sector starting points and identifies rotor pole count and magnetic‑pole direction, removing human errors, improving test efficiency, replacing manual sampling and enabling 100% full inspection.


• Supporting 2D & 3D full‑area magnetic‑field scanning, this unit measures dozens of critical metrics for permanent‑magnet rotors, including pole peak/min/average values, magnetic‑field deviation, pole angle, pole width, pole count and harmonic analysis. Auto‑generated X‑Y rectangular‑coordinate graphs, polar‑coordinate charts, 3D magnetic‑field cloud maps and harmonic spectra reconstruct real‑world rotor magnetic‑field distribution, catering to both R&D analysis and mass‑production quality inspection.


• Built with a modular structure, it supports on‑demand customization of test travel, clamping mechanisms and test programs. Compatible with samples ≥Φ8 mm, it accommodates cylindrical permanent‑magnet components, multi‑pole magnetic rings, motor rotors of various sizes, magnetic rollers and magnetic tiles, covering micro precision to large‑scale industrial motor rotors. Independent hardware and software customization is offered; tailor‑made solutions can be adapted to production‑line layouts and inspection standards for superior flexibility.


• Its built‑in professional magnetic‑property analysis software enables real‑time data storage, historical‑data query, batch‑data comparison, auto report generation and data printing. All test logs are automatically saved to achieve full‑process inspection traceability. Customizable pass‑fail thresholds support auto‑grading to reject defective parts with uneven magnetic fields, insufficient magnetization, local demagnetization or magnetic‑pole offset. Seamless integration with enterprise MES systems facilitates intelligent, digital quality‑control upgrades for production facilities.

1. Motion Accuracy: Precision servo drive for X/Y/Z axes. Positioning accuracy ±0.02 mm, minimum resolution 0.01 mm, and the rotary axis is fully adjustable from 0 to 360°.

2. Scanning Performance: Supports 2D planar and 3D volumetric full-area scanning. The maximum rotary test speed is 10 seconds per revolution, suitable for mass production inspection.

3. Measurable Parameters: Full-dimensional parameters including pole number, magnetic pole peak/valley value, average magnetic field, angular deviation, magnetic pole area, total harmonic distortion and more.

4. Applicable Samples: Various permanent-magnet components such as permanent-magnet motor rotors, multi-pole magnetic rings, cylindrical permanent magnets, magnetic tiles and magnetic rollers.

5. Extended Functions: Supports linked magnetic flux inspection after magnetization, temperature monitoring, equipment interlock protection and cloud data synchronization.

With one-stop customized services, Yidi developed dedicated test solutions and fixtures tailored to the customer’s sample specifications, inspection standards and production-line requirements. Full-range services including equipment installation & commissioning, technical training, lifelong technical support, equipment maintenance and upgrade are provided. This enables rapid on-site deployment and worry-free operation for enterprises. Moreover, this successful case can be replicated to more robotic motor manufacturers.