What Is Friction Torque?

Torque: Product (M) of force (F) and arm (L). That is: M = F · L. Where L is the vector from the axis of rotation to the force and F is the vector force. Therefore, the friction torque is the product of the friction force and the friction arm.

Dimension of moment is distance multiplied by force;

In the final analysis, the generation of frictional torque is the result of the friction of various parts of the bearing. They are divided into the differential sliding inevitably generated by the rolling contact surface and the micro-sliding sliding friction caused by the structure, caused by the lubricant itself and the contact surface. Viscous friction due to rotation and agitation, friction caused by speed and air, pure rolling friction caused by elastic hysteresis of the material when there is no sliding, sliding friction caused by sliding contact surfaces, and sliding friction caused by rolling body spin and sealing devices . By analyzing the above-mentioned mechanism of friction, we can get the influencing factors of friction torque. They have factors that cause errors in the shape of the rolling surface, such as the internal clearance of the bearing, the current status and size of the part, the amount of deformation of the part, the pollution of the bearing, etc., the structure of the bearing and the cage, the ball diameter and the number of balls , Bearing contact angle and other effects, there are processing technology and the effects of lubricants, there are loads and speed effects. ^[2]

Friction torque can cause a discontinuous movement of a two-way system, a crawling phenomenon of a one-way low-speed system, resulting in unstable system operation, and a tracking error of a two-way, high-speed system. Friction torque has a serious impact on the performance of the system. In order to overcome this effect, the traditional gain feedback method has been unable to meet the requirements for overcoming the impact of friction torque and continuously improving system performance. Therefore, the research on the compensation of friction torque directly has been paid more and more attention by scientific researchers. Due to the rapid development of microprocessor technology, the research on compensation technology of friction torque has become a very popular research direction. Literature on friction compensation research. We can use friction compensation to eliminate or reduce the discontinuous operation of a two-way moving system, to eliminate or reduce the crawling phenomenon of a unidirectional, low-speed system, and to eliminate or reduce the Tracking error. In the field of motion control, it can be considered to use appropriate friction compensation methods to achieve positioning and tracking accuracy has also become a common understanding of scientific researchers. ^[1]

Stiffness, angular momentum, acceleration, stress, torque, inertia, reference system, power level, displacement, impulse, angular displacement, pressure, angular velocity, tension