China research team proposes novel bearing friction evaluation method inspired by gyroscopic rotation

June 3, 2025, Tianjin News - A research team from the School of Mechanical Engineering of Tianjin University recently proposed a new method for testing the friction performance of rolling bearings. This method is inspired by the phenomenon of gyroscope rotation and is expected to improve the performance evaluation ability of high-precision bearings in extreme environments.

The research was led by Professor Ren Chengzu and the results have been published in the international academic journal Friction. The team has long been committed to the research of processing and testing technology for high-precision rolling bearings. In practical applications, it was found that even bearings manufactured under the same production conditions have subtle differences in friction performance, but traditional measurement methods are difficult to accurately distinguish.

The commonly used friction torque sensors are greatly affected by working conditions, and the data fluctuates significantly, which cannot effectively identify the tiny friction differences between high-precision bearings. To solve this problem, the researchers changed their thinking and adopted a method based on the kinetic energy theorem to reflect the friction characteristics of the bearing by measuring the time it takes for the bearing to stop rotating.

"Just like the longer the gyroscope rotates, the smaller the friction, we can calculate the energy loss by recording the deceleration process." Ren Chengzu said, "Time is a very precise variable, which makes our method more stable."

In the experiment, the researchers designed a special device to allow the bearing to stop naturally after high-speed rotation, and used a high-precision magnetic grating angular velocity sensor to record the entire deceleration process. By analyzing the changes in friction characteristics at different speeds, they proposed the comprehensive indicator of "equivalent friction coefficient" and successfully sorted ten bearings from the same batch stably.

Repeated experiments have shown that this method has good consistency and repeatability, and can effectively identify tiny friction differences. This breakthrough not only improves the accuracy of bearing performance evaluation, but also provides technical support for the research and development of key components in the future high-end equipment, new energy vehicles and aerospace fields.