Summary: | 碩士 === 樹德科技大學 === 資訊工程系碩士班 === 104 === The purpose of this study is to explore the correlation between the kick serve hit by tennis players at different performance levels and the vibration spectra.
The subjects of the study were ten tennis players participating in the National Ranking Competition, with five players as elite players and five as good players with the age of 22.5±3.7 years old, height of 177.4±5.95 cm, weight of 73.4±5.66 kg and experience of 12.2±3.12 years. Wireless inertial sensors equipped with tri-axial accelerometers (the sampling frequency is 3333Hz) were applied on the tennis rackets and the racket vibration data of the impact moment of 20 successful kick serves were captured. This study applied MATLAB arithmetic operators to capture time data of the major action as the basis for comparative analysis among the players so as to understand the differences in the racket’s tri-axial vibration frequency domain, with the significance level α set at .05 (α=.05).
It is found in the research results that for the same player, there showed no significant difference in the ball speed when serving the ball with a racket equipped with or without an inertial sensor. Elite players’ amplitudes of the racket vibration in Y-axis are higher than good players but lower than good players in X-axis. No significant difference was found in the amplitude of the racket vibration in axis Z in both groups. The results indicate that for tennis players to hit kick serve, the amplitudes of the racket vibration are larger in Y-axis when the player can hit the kick serve better. The data can be helpful for teaching observation and correction. The research results can serve as reference for school teachers and tennis coaches at different levels, and also for related research in the future.
|