Linear Motor Stability Testing
As mentioned in our previous articles, the core XY-axis motion system of our product is powered by 8 sets of linear motors, a mainstream power solution widely used in industrial control scenarios.
Higher closed-loop motion accuracy. Linear motors are widely used in high-precision industrial fields, delivering accuracy of up to 1 micrometer (1μm).
Another core advantage is maintenance-free operation. Unlike traditional transmission structures that rely on gears and belts, which are prone to elongation, loosening, slippage, and wear over time and therefore require regular maintenance, linear motors use electromagnetic drive. With a consistent 0.5mm gap between the mover and the stator, they achieve nearly zero transmission loss.
Additionally, this direct-drive structure enables a higher ceiling for speed and acceleration, lower motion noise, and more outstanding comprehensive motion performance.
These engineering advantages are highly impressive, yet the high cost of industrial-grade linear motors (often thousands of US dollars per set) quickly brought us back to reality. Our team held lengthy discussions and remained hesitant for a long time during the solution selection phase.
Nevertheless, the conclusion is clear: linear motors boast irreplaceable advantages and enormous development potential. High cost is only a temporary constraint. To deliver groundbreaking product performance, we must overcome this challenge.
Ultimately, we finalized the linear motor power solution. More importantly, we decided to redesign the linear motor structure from scratch to reduce the overall cost by at least 10 times.
To achieve this goal, we conducted long-cycle, in-depth design iterations and engineering verification. Today, we share part of our research and test results with everyone.
1μm Repeat Positioning Accuracy
In the early design stage, we set a core target of 1μm repeat positioning accuracy for the linear motor system. We adopted a 12-bit magnetic encoder with a 4mm magnetic pole pitch. Its theoretical resolution is calculated as 4/(2^12) = 4/4096 ≈ 1μm.
After approximately 5 rounds of iterative design and optimization, we successfully achieved the 1μm repeat positioning accuracy design target.
Max 6g Acceleration Test
Linear motors feature exceptional speed and acceleration limits. Benefiting from the elimination of complex intermediate transmission structures, they deliver ultra-fast response performance.
Through actual bench testing, we verified that the maximum acceleration of the printer’s X-axis and Y-axis can reach 4g and 6g respectively.
50,000+ Hour Linear Motor Service Life Test
A high-quality power system must feature outstanding stability and durability. We refuse to allow our machines to develop various motion system failures after only 3,000+ hours of operation. Therefore, we launched a full range of tests from the project initiation stage.
288-Day Continuous Aging Motion Test
We launched a 24/7 non-stop aging test starting from October 9, 2025. To date, the test has lasted 288 consecutive days, achieving 6,912 hours of fault-free continuous motion. The test is still ongoing and will continue to run for long-term verification.
*Note: The test was temporarily suspended twice due to the office relocation and moving the equipment to the factory.
Linear Guide Rail Salt Spray Corrosion Test
Linear motors operate via non-contact electromagnetic driving and rely on linear guide rails for positioning and movement, making the quality of guide rails critical to system stability. Salt spray testing is a key indicator to evaluate the corrosion resistance and service life of guide rails. Therefore, we selected linear guides from multiple brand suppliers and other 3D printers for salt spray testing.
1) Test chamber temperature: 35°C; Pressure barrel temperature: 47°C; Saline solution concentration: 5%; PH: 6.5~7.2.
2) Inspection was performed every 24 hours after continuous spraying, with the total test duration lasting 48 hours.
Demagnetization Curve Test
The demagnetization curve is a key characteristic curve that describes how the internal magnetic flux density of a linear motor magnet changes with an applied reverse magnetic field after the external magnetic field is removed. This characteristic is used to determine the extent of magnetization loss under different reverse magnetic field strengths.
Professional laboratory testing verified that Hcj=15.71 kOe (approximately 1250 kA/m), indicating excellent demagnetization resistance.
Coil Temperature Resistance Test
We embedded NTC thermistors between the mover coils and optimized the board firmware to enable real-time temperature display on the Klipper Fluidd interface. All temperature data can be stored, read and downloaded from the Klipper system for continuous monitoring and analysis.
Test Results:
With the stall current limited to 3A, the motor maintained a continuous stall state. The internal temperature of the mover finally stabilized at approximately 77°C. Meanwhile, infrared thermal imaging measurement showed the maximum surface temperature of the mover shell stabilized at about 67°C, fully meeting the design temperature tolerance requirements.
After a series of tests and validations, we can confidently confirm that our self-developed linear motor motion system can operate stably for more than 50,000 hours.