拔河機的開發與評估

Abstract

目的：設計開發一新操作型態之拔河訓練系統，提供可以改變的阻力以及立即的回饋。方法：本系統概念為操作時可以改變阻力，搭配軟、硬體讓使用者可以自行控制阻力改變的比例以及頻率，硬體利用無段變速系統(CVT)的原理來達到操作過程中阻力變化的效果，軟體系統分為拉力值判斷與伺服馬達控制兩部份，針對系統所作的測試為：電子張力計的校正、阻力改變的量測、軟體的執行測試。結果：軟體部份，系統程式的反應速度約為12.8±3.3毫秒，且可完成所要求之動作；自行設計無段變速系統在負荷1.1kg的情況下，阻力最大量測值為2.45kg、最小值為1.23kg，理論值與實際值的誤差約在0.28~0.45kg。結論：軟體部份已建構完成且可行；硬體的部份目前在1.1kg的負荷下可以提供連續、可變的阻力，但在大於2kg以上的負荷的情況下硬體會有空轉的現象發生。

Purpose: To design a new type of tug of war training system. This new system could provide variable resistance and immediate feedback to the user. Methods: To provide variable resistance as operating, the change of loading in percentage and frequency could be controlled by the combining with hardware and program. We used continuously variable transmission (CVT) in our system to make loading change. The program edited by LabVIEW was used for loading judgment and servo motor control. Load cell calibration, variable resistance measurement, and software test were assessed. Result: The reaction time of the program is 12.8±3.3 millisecond. Using the CVT, the loading of the 1.1kg could be changed from 1.23kg to 2.54kg. The error between theoretical value and actual value is about 0.28kg to 0.45kg. Conclusion: The program is practical for operation, and CVT could provide continuously variable resistance. However, system will be idel when the loading is greater than the 2kg.