在傳統CNC控制系統中，無論是單軸還是多軸控制，其控制概念都是希望藉由降低各軸之追跡誤差，以降低最終加工誤差。但是，以追跡方式作為控制法則的前提必須各軸運動時彼此不會互相影響，然而實際之工具機並非如此。
本研究以降低輪廓誤差為目的，提出一套多層迴路任務座標框架控制法則，能夠應用於任意階數與任意延遲之系統，搭配飽和權重之參數設定，提高多層迴路控制器的穩健性，並針對內層速度迴路的回授量化雜訊問題，提出一套速度估測器，藉此解決多層迴路系統因雜訊干擾產生過大的補償命令，避免控制輸入飽和之問題。
本研究之多層迴路輪廓控制系統實現於東台CNC車床TC-2000之XZ平台，並與常見之各軸獨立追跡誤差控制器比較。在實際循圓測試中，多層迴路任務框架控制器對於馬達內部編碼器所量測之輪廓誤差，能提供57%之改善，以循圓測試儀量測，對真圓度也能提供約11.8%之改善；在低速度高曲率軌跡的實驗，多層迴路任務框架控制器對於最大輪廓誤差，能提供約66%之改善，高速度高曲率軌跡的實驗，則是能提供約60%之改善。

In the traditional CNC control system, no matter how many axes the CNC machine has, the control objective is to increase the quality of the final machined products through the small tracking error of each axis. The premise that the small tracking error guarantees good machining quality relies on independency of each axes; however, the real machine tool is not the case.
This motivates the research in this thesis. A new multi-loop control architecture based on the task coordinate frame rule is proposed that can be applied to systems with any order and arbitrary delay, so that better contouring control accuracy can be achieved. Besides, we use a saturation weighting parameter to improve the robustness of this multi-loop contouring controller. Moreover, a velocity estimator is proposed to eliminate feedback quantization noise in the inner velocity loop, which can prevent the controller from generating excessive compensation commands due to quantization interference.
The multi-loop contour control method of this study is realized on the XZ-table of Tongtai CNC lathe TC-2000, and the experimental results are compared with those of the common single-axis tracking control method. In the circular trajectory experiment, the multi-loop task coordinate frame controller can improve the contouring control performance by 57% based on the measurments of motor encoders, and improve the roundness by 11.8% based on the measurements of the double ball-bar. Additionally, in the experiment of the low speed and large curvature trajectory, the multi-loop task coordinate frame controller can improve the maxumium contour error by 66%, while in the experiment of the high speed and large curvature trajectory, the improvement is 60%.

目錄

摘要 i
ABSTRACT ii
誌謝 iv
目錄 v
圖目錄 viii
表目錄 xii
第一章 緒論 1
1.1. 研究背景 1
1.2. 研究目的與發展概況 2
1.3. 研究貢獻 3
1.4. 論文架構 4
第二章 相關研究 5
2.1. 輪廓控制技術 5
2.1.1 輪廓誤差與追跡誤差之定義 5
2.1.2 輪廓控制器比較與特點分析 6
2.2. TCF控制器之設計方法 8
2.3. 極點/零點對消法則與回授線性化 12
第三章 多層迴路任務座標框架系統設計（MTCF） 17
3.1. 多層迴路任務座標框架控制策略（MTCF） 17
3.2. MTCF之內層速度控制器（MTCF-V） 19
3.2.1 速度/轉矩轉移函數（Transfer Function） 20
3.2.2 任務座標系轉換 23
3.2.3 MTCF之速度控制器設計 24
3.3. MTCF之外層輪廓控制器（MTCF-C） 27
3.3.1 MTCF之內層閉迴路分析 27
3.3.2 MTCF之位置控制器 Cpp 設計 30
3.3.3 MTCF之輪廓控制器 Cp 設計 31
第四章 多層迴路任務座標框架分析與改善 37
4.1. MTCF控制架構分析 37
4.2. 速度估測器 38
4.2.1 速度估測器之設計 38
4.3. 摩擦力補償 43
4.3.1 建立摩擦力模型 43
4.3.2 摩擦力補償策略 46
第五章 控制器參數設計與模擬 49
5.1. 控制器參數設計 49
5.1.1 系統鑑別 49
5.1.2 控制器參數設計 53
5.2. 模擬結果與分析 61
5.2.1 理想條件之模擬測試 62
5.2.2 非理想條件之模擬測試 66
第六章 實驗結果與討論 74
6.1. 硬體架構 74
6.1.1 XZ平台 74
6.1.1 上位控制器 75
6.2. 實驗結果分析 76
6.2.1 實驗參數調整 76
6.2.2 循圓測試 – 雙球棒量測結果 80
6.2.3 循圓測試 – 光學尺量測結果 82
6.2.4 橢圓軌跡測試 - 馬達編碼器量測結果 84
6.2.5 橢圓軌跡測試 - 光學尺量測結果 89
第七章 結論 92
7.1. 研究總結 92
7.2. 未來展望 93
參考文獻 94

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