隨著工業的進展，製造業目前已處於時間與品質並重的時代，因此目前自動化製造設備一直朝向高速高精度的方向發展，本論文就針對CNC工具機的剛性攻牙功能做伺服迴路控制，剛性攻牙與一般傳統的可動式浮動攻牙最大的不同，剛性攻牙加工的速度比浮動攻牙快很多，且可以降低刀具之摩耗，如此可以使加工時間縮短並節省成本。由於剛性攻牙在加工過程中，主軸與Z軸必須維持一定的位置比例，即主軸每旋轉一圈，Z軸必須往下一個節距(pitch)，本論文分別採用兩種不同的方式來達到此一目的。 第一種方式是採用Z軸追隨主軸的方式，在本論文中考慮到伺服系統普遍存在的延遲問題，因此在Z軸加入前饋控制器(Feedforward Controller)來增加系統的追蹤能力。 第二種方式是採用主軸與Z軸個別給予一定比例的位置命令，但由於主軸與Z軸的動態不同，所以必須使用交叉耦合控制器(Cross-Coupled Controller, CCC)作補償運算，來增加兩軸間的協調性，以降低兩軸間的輪廓誤差；另外，為了達到高速高精度之需求，最後本論文使用了前饋控制與交叉耦合控制之合成系統，並探討了前饋控制與交叉耦合控制之間的交互作用及此二控制器在一高速高精度之運動控制系統中所扮演的角色。 關於上述本論文所發展的CNC工具機之剛性攻牙功能的伺服迴路控制，除了理論推導之外，論文中並給定實際運動進給的條件進行模擬與實驗驗證，證明這些伺服迴路控制的可行性。 As the development in industry, time and quality are more and more important in manufacturing industry. Therefore, automatic manufacturing machines are tending to high speed and high precision. This thesis is aimed at the servo loop control of rigid tapping function on CNC machine tools. Rigid tapping has several advantages that are faster machining, lower cost and higher precision than traditional floating tapping. The positions of the Spindle and the Z-Axis should maintain the same ratio at the process of rigid tapping. It means that when the Spindle is rotated one turn, the Z-Axis should be fed one pitch. The thesis uses two different methods to achieve this purpose. In the first method, the Z-Axis is controlled to trace the Spindle. The research adopts a feedforward controller to improve the tracking performance of the Z-Axis. In the second method, we consider issuing individual constant ratio position command to the Spindle and the Z-Axis. Because of the differences in dynamics of the Spindle and the Z-Axis, we use a cross-coupled controller to reduce the contouring error between the Spindle and the Z-Axis. The hybrid system of the feedforward controller and the cross-coupled controller is integrated to satisfy the requirements of high speed and high accuracy motion control. Finally, the above servo loop control of rigid tapping on CNC machine tools is verified by the simulation and experimental results.
