現今之製造系統中，如何降低輪廓誤差為一重要之研究議題。因此，現代的工具機需具備高精度及高效率的輪廓加工能力，才能在進行複雜輪廓外型或轉角之加工時依然滿足加工精度之要求。一般加工而言，較差的循跡精度往往出現於加速度量具急遽變化之較大曲率線段。為解決此問題，本論文針對尖角軌跡循跡運動提出一基於畢式曲線之軌跡修正規劃法，所提之方法為根據模擬系統動態響應、估測輪廓誤差及樣板搜尋演算法，透過二次微分連續之畢式五階雲型曲線以建構一修正之尖角命令軌跡。其優點為可藉由預先規劃之修正型尖角輪廓命令軌跡，使得實際切削軌跡可以接近原始軌跡路徑，導致轉角循跡精度可以進一步提升。本論文藉由多種不同尖角循跡運動實驗，驗證所提出方法之可行性。實驗結果顯示本論文所提出之方法的確可以降低尖角循跡運動之輪廓誤差。

Contour error reduction is an important issue in today’s industrial manufacturing systems. Thus, modern machine tools are required to provide high-precision and high-efficiency contour machining capabilities, particularly when machining complex contour shapes or sharp corner angles. Generally, poor machining performance may occur due to the abrupt change of acceleration at the portion of the curve with larger curvature. To cope with this problem, a modified trajectory planning scheme based on PH (Pythagorean Hodograph) curve is proposed for sharp corner angle contouring tasks. The scheme is developed according to simulated system dynamic response, estimated contour error, and a pattern search algorithm to construct a modified sharp corner contour by using C2 PH quintic spline curve. The main advantage of the proposes scheme is that it can force the actual cutting trajectory moving closer to the original command path by exploiting a modified command trajectory at sharp corner contour in advance. Therefore, the corner contouring accuracy can be further improved. Finally, to evaluate the effectiveness of the proposed approach, several different sharp corner contour following experiments were conducted. The experimental results indicate that the proposed approach can indeed reduce contour error in sharp corner angle contour following applications.

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