應用田口方法於 Statapult 投石機參數最佳化

Abstract

中文摘要 本研究以 Statapult 投石機作為實驗平台，探討不同瓶蓋與投石機操作參數對投擲距離之影響，並應用田口方法尋找可使瓶蓋投擲距離最大化之最佳參數組合。研究中將投擲距離設定為望大特性，選定瓶蓋種類、發力臂位置、拉力位置及發射角度四項控制因子，且各因子皆設定三個水準，並採用L! (3" )直交表進行實驗設計。實驗完成後，利用 Minitab 進行 S/N 比分析、主效應分析、最佳參數預測及變異數分析，以判斷各因子對投擲距離之影響程度。分析結果顯示，發射角度為影響投擲距離之最主要因子，其 Delta 值為 13.31，且變異數分析中 P 值為 0.018，達顯著水準。綜合各因子最佳水準後，本研究得到最佳參數組合為 A3、B2、C1、D1，亦即鋁瓶蓋、發力臂位置為中孔、拉力位置為最上孔、發射角度為 90°。經三次確認實驗後，所得 S/N 比為 62.7368，並落於 95%信賴區間內，呈現本研究之最佳參數組合具備良好再現性，亦驗證田口方法可有效應用於投石機投擲距離最佳化分析。

Abstract This study used a Statapult as the experimental platform to investigate the effects of different bottle caps and operating parameters on throwing distance. The Taguchi method was applied to determine the optimal parameter combination for maximizing the throwing distance of bottle caps. In this study, throwing distance was defined as the larger-the-better quality characteristic. Four control factors were selected, including bottle cap type, arm position, pulling position, and launch angle, with each factor consisting of three levels. An L9(3⁴) orthogonal array was adopted to arrange the experimental trials. After the experiments were completed, Minitab was used to conduct signal-to-noise ratio analysis, main effects analysis, parameter prediction, and analysis of variance. The results showed that launch angle was the most influential factor affecting throwing distance, with a Delta value of 13.31. The analysis of variance also indicated that launch angle was statistically significant, with a P-value of 0.018. Based on the main effects analysis, the optimal parameter combination was determined as A3, B2, C1, and D1, corresponding to an aluminum bottle cap, middle arm position, upper pulling position, and 90° launch angle. Three confirmation experiments were further conducted under the optimal condition, and the calculated S/N ratio was 62.7368, which fell within the 95% confidence interval. Therefore, the proposed optimal parameter combination demonstrated good reproducibility, confirming that the Taguchi method can be effectively applied to optimize the throwing distance of a Statapult system.