Assisted training of table tennis based on adaptive contact judgment threshold generation algorithm and universal sports assistance training framework

Table tennis is a highly technical and fast sport, which requires athletes to have good technical level and physical fitness. In order to achieve more efficient and intelligent table tennis assisted training, a knowledge-based general sports-assisted training framework (KGSTF) was introduced, and the functions of each module were analyzed. At the same time, an adaptive contact judgment threshold generation algorithm was proposed for the implementation of this framework in specific table tennis training. On this basis, a pose correction method based on contact position constraints and an optical motion capture data preprocessing method were designed, and an automated program was developed to handle data stitching, clutter removal, and labeling. The results showed that in the validation experiment based on the adaptive contact judgment threshold generation algorithm, by incorporating the optimization results of the previous frame into the objective function, the optimized actions can be made smoother. Meanwhile, the landing error of the advanced subjects was only 1.539 cm when receiving a slight topspin serve, 0.947 cm when receiving a downspin serve, and 5.294 cm when receiving a strong topspin serve, which illustrates that a smaller serve speed has more stability. In addition, the return success rate of advanced subjects in the slight topspin mode was the best, with a maximum value of 95.12% and an average of 91.38%. The average return success rate of intermediate subjects in the slight topspin mode was as high as 75.36%. Compared with the strong topspin and downspin service modes, the return success rate was increased by 13.72% and 26.26%, respectively. Meanwhile, the return success rate of advanced subjects was significantly higher than that of other subjects. The results show that the sports auxiliary framework designed by this study can be effectively applied to the sports evaluation of table tennis auxiliary training, which is helpful to provide personalized training guidance and improvement suggestions for table tennis players, and promotes the scientific and professional development of table tennis.