Inertial Sensor Applied to Movement Analysis on Topspin Serve

• Main Authors: Ken-Chao, 趙懇
• Other Authors: 涂瑞洪
• Format: Others
• Language: zh-TW
• Published: 2014
• Online Access: http://ndltd.ncl.edu.tw/handle/59973916868943230775

碩士 === 樹德科技大學 === 資訊工程系碩士班 === 102 === Department of Computer Science and Information Engineering, SHU-TE University Inertial Sensor Applied to Movement Analysis on Topspin Serve Student：Chao Ken Advisor：Dr. Wu , Hung Chih ABSTRACT Purpose: The purposes of this research were to analyse the effect factor of accelerating of tennis during serving by wireless inertial sensor, and to compare the difference of two groups whose average speed of flat serving are higher or lower, defining them as high-speed group and low-speed group. We assumed that tennis is accelerated during the acceleration of body segments and measured the experiment data by swinging racket. Methods: We have selected two groups of tennis players. Both of the groups contain five right-handed players. For the high-speed group, the average height, weight and age are 180 ± 5.83cm,77 ± 3.39kg, and 26.6 ± 2.70 years old, while the average height, weight and age of the low-speed group are 175 ± 5.36cm, 69.8 ± 5.31kg and 20.4 ± 2.70 years old. Results: 1. By calculating the difference of movement stability between these two groups, the average values are 56.27 and 51.19 m/s. 2. During the -100ms~100ms of the hitting moment of serving, the maximum acceleration of the low-speed group are 19.28%(X-axis), 65.20%(Y-axis), 37.07%(Z-axis) less than high-speed group. 3. For the high-speed group, the kinetic chain of the serving are as follows: B and I players motion order (wrist - elbow - palm) were 17 times and 14 times, C and J players motion order (elbow - palm - wrist) were 13 times and 9 times, D player motion order (elbow - wrist - palm) is 9 times; A, E, F and H players motion order (elbow - wrist - palm) were 19 times, 17 times, 14 times and 10 times, G player motion order (wrist - palm - elbow) is 12 times. Conclusions: 1. The higher movement stability shows that the performance of the high-speed group is less stable than the low-speed group. 2. Comparing the absolute value of the maximum and the minimum acceleration during the -100ms~100ms of the impact moment of serving, the value of high-speed group is larger the low-speed group, showing that the high-speed group consumes more stamina during the procedure. 3. Most members in high-speed group start kinetic chain from elbow, which is different from the members in low-speed group, starting kinetic chain from wrist. For the low-speed group, the second part of kinetic chain mainly tends to be elbow. Therefore, we can apply inertial sensor to identify players force order and with the help of knowing the high-speed group’s force order, we can improve and adjust the force order to expect a better performance in the future. Key words: Acceleration, Movement stability, Kinetic chain