曲率半徑方法在鏈球運動中的應用

The Application of Curvature Radius Method in Hammer Throw

李靜雯(Ching-Wen Lee)

《運動教練科學》 13期 (2009/03) Pp. 93-101

https://doi.org/10.6194/SCS.2009.13.06

摘要

目的：本研究的目的在以數學方程式求得鏈球運動時鏈球軌跡的曲率半徑，並比較不同鏈球成績（63.20及68.46公尺）的曲率半徑變化，藉此瞭解選手在動作過程中對鏈球的拉放情形。方法：研究對象是台灣地區的鏈球紀錄保持人，以二台Peak-Performance高速攝影機(120Hz)同步地進行攝影受試者二次不同成績的投擲表現，鏈球的運動學參數則藉由Peak Motus分析軟體求得，而曲率半徑方程式則由鏈球的直線速度和直線加速度導出。結果：結果顯示在二次鏈球投擲表現時，鏈球行進軌跡之曲率半徑變化型態完全不同，成績較佳者的曲率半徑變化較有週期性，在鏈球最高點和最低點的曲率半徑較大。結論：以曲率半徑方法來檢視鏈球的軌跡，可提供選手在擲鏈球過程時的參考，另外也建議可以使用曲率半徑方法來瞭解其它種三維曲線運動項目的動作變化型態。

關鍵字

軌跡 ； 曲線運動 ； 週期性

並列摘要

Purpose: The purpose of this study was to compare the curvature radius of different performance (63.20 m and 68.46 m) of hammer throw. Methods: The subject, who is the present record holder of hammer throw in Taiwan. Two Peak-Performance high speed video cameras operating at 120 Hz were simultaneously used to record different performances of the subject. Kinematic parameters of hammer head were derived from Peak Motus software. The curvature radius function was derived from linear velocity and linear acceleration of hammer head. Results: The results indicated that the patterns were completely different between two performances of hammer throw. The curvature radius of better one was more periodic than the other one, and was larger at the highest points and the lowest points of the orbit during hammer throw. Conclusion: It would provide some information to athlete through the curvature radius method to examine the orbit of hammer head during hammer throw. It was also suggested that the pattern of other sport events related to 3D curve motion may also be realized by the method of curvature radius.

並列關鍵字

orbit ； curve motion ； periodic

參考文獻

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