近年來機械手臂廣泛應用於各式工業加工製程，如:焊接、拋光、去毛邊以及噴漆等，而此類加工精度大多取決於循跡控制性能之優劣。然而在目前機械手臂之循跡應用中，其循跡之軌跡大都仰賴人工繪圖或由機械手臂教導器進行事先教導，不僅耗時且精度上有一定的限制。再者，機械手臂之控制性能將受限於事前之機構校正精度。有鑑於此，本論文引入視覺伺服技術於循跡控制問題，以架設於上方之攝影機對待加工物體進行拍攝，並產生參數式曲線來描述物體輪廓做為位置命令。根據此參數式曲線，本論文發展一命令插值器以產生影像平面上之軌跡命令。接著將此軌跡命令轉換至架設於側邊之攝影機影像平面實現以影像為基礎之視覺伺服(IBVS)，以確保機械手臂之末端點可準確沿著物體輪廓運動。然而在IBVS應用中，其Image Jacobain需有準確的末端點深度量資訊，因此本論文提出基於參數式曲線之深度估測法以提供精準的深度資訊，進而提昇視覺伺服控制之性能。最後，本論文採用Dynamic Look and Move設計視覺迴路控制器外亦自行設計機械手臂之內迴路速度控制器，其中並引入基於參數式曲線之前饋補償以降低系統之追蹤誤差。實驗結果顯示由本論文所發展之視覺伺服架構，針對未知數學模型之輪廓循跡控制問題，確實展現令人滿意之性能。

In recent years, robot manipulators have been used extensively in industrial manufacturing processes such as welding, polishing, deburring and spraying. The precision of these applications depends on the performance of contour following control. Normally, trajectory generation in contour following tasks relies on manual drawing or trained in advance by a robot teaching panel, which is time-consuming and of limited accuracy. Furthermore, control performance of the robot manipulator is also restricted by the accuracy of prior mechanical calibration. As a consequence, this thesis integrates visual servoing into contour following control. The image of the object for machining is taken by a ceiling-mounted camera. The detected object contour is described by a parametric curve. Based on this parametric curve, an interpolator is developed to generate the trajectory command in the image plane. Secondly, this trajectory command is converted to the position command of the image plane of the camera that is located on the side of the object for machining to implement IBVS so as to ensure that the end-point of the robot arm can accurately move along the object contour. However, the exact end-point depth information of the Image Jacobian is necessary in IBVS, therefore this thesis proposes the parametric curve based depth estimation method to enhance visual servoing performance with accurate depth information. Finally, in addition to designing the visual loop controller, the inner loop velocity controller including parametric curve based feedforward compensation is designed in this thesis to reduce the tracking error as well. Experimental results indicate that the proposed approach exhibits satisfactory performance in contour following tasks of the objects without known mathematical models.

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