1. Physical test methods and principles
Measuring the friction of table tennis racket rubber can be achieved through some physical test methods. Among them, the most commonly used is to use a friction coefficient tester. This instrument measures the friction between the rubber and the table tennis ball by simulating the contact and relative motion between the rubber and the table tennis ball. Its principle is based on the law of friction. Under a certain positive pressure, the table tennis ball is made to slide or roll on the rubber surface at a stable speed. The instrument measures the required tension or torque at this time through the sensor, and then calculates the friction coefficient according to the formula. For example, place the table tennis ball on the inclined rubber surface at a certain angle and speed, gradually increase the inclination of the rubber surface, and when the table tennis ball starts to roll at a constant speed, the friction coefficient is calculated according to the angle and gravity at this time, thereby quantifying the friction of the rubber.
2. Evaluation of actual batting effect
In addition to physical testing, evaluating the friction of the rubber from the actual batting effect is also an important method. During the batting process, friction has a key impact on the rotation and control of the ball. The friction of the rubber can be measured by observing the rotation speed and arc of the ball after the batting. If the friction of the rubber is large, the athlete can rub the ball more effectively when hitting the ball, making the ball rotate strongly. For example, when pulling a loop, the topspin of the ball will be more obvious, the arc will be more curved and the speed will be faster. For controlled shots such as rubbing and slicing, the rubber with high friction can better control the landing point and rotation direction of the ball. By comparing the rotation and trajectory changes of the ball when hitting the ball with different rubbers, you can have an intuitive feeling and comparison of the friction of the rubber.
3. Microscopic surface structure analysis
The microscopic surface structure of table tennis racket rubber has an important influence on friction, so analyzing it is also helpful to measure friction. Use equipment such as electron microscopes to observe the texture, particle distribution and roughness of the rubber surface. Generally speaking, the rougher the rubber surface, the denser the particles and the regular the shape, the larger the contact area with the ball, and the greater the friction. For example, the small particle structure on the surface of the anti-rubber rubber, if these particles are closely arranged and the height and shape are consistent, can better contact with the ball surface when hitting the ball, increasing friction. By comparing the microstructures of different rubbers, we can preliminarily judge the magnitude of their friction.
4. Refer to professional athlete feedback and experimental data
Professional athletes have a keen sense of the friction of different rubbers in long-term training and competition. Their feedback is an important reference for measuring the friction of rubbers. At the same time, professional sports research institutions will conduct a large number of experimental studies to collect data on different rubbers under various hitting conditions. Combining the experience and experimental data of these athletes, a relatively accurate rubber friction evaluation system can be established. For example, by statistically analyzing the data of the ball rotation speed and the flight arc of the ball when multiple athletes use different rubbers, combined with the athletes' own evaluation of the rubber friction, a rubber friction measurement standard that is more in line with the actual situation can be obtained.
