近年噴頭噴印技術隨著積層製造成長而發展快速，由於壓電噴頭的快速噴印及高精準度等優勢，可印製解析度高的成品，進而成為3D列印之材料噴印技術之主流。隨著噴印精準和高解析度的要求，噴印前之對位系統為關鍵技術之一。鑑此，本研究主要目的是採用自動影像視覺演算校正，開發基於材料噴印技術(Material-jetting)之光固化彩色3D列印系統，達到自動對位系統、高解析度、高精確度列印目的。首先，在列印模組端結合五種光固化材(青色、洋紅色、黃色、白色、黑色)和支撐材的串列式六顆噴頭列印系統，接著在噴印初始時設定對位初值並列印對位圖檔做為參考，經過掃描器取像；再利用視覺處理演算法擷取噴印圖檔特徵，透過影像對位運算，並得到對位噴印所需要設定之列印參數。本研究提出多噴頭對位自動化，取代耗時的人工校正所需的耗時，降低對位誤差，提高列印品質，也提供具有多噴頭之3D列印系統更精準對位流程。

In recent years, the piezoelectric heads printing technology has grown and developed rapidly with the additive manufacturing. Due to the advantages of rapid printing and high precision of piezoelectric heads, it becomes the mainstream of 3D printing with material jetting printing technology. With the printing precision and high resolution requirements, the printing front registration system is one of the key technologies. Therefore, the main purpose of this study is to develop an automatic print head alignment algorithm for a color 3D additive manufacturing system based on a material jetting technology. An automatic alignment system for high precision printing can be achieved. First, a serial six-head print system that combines five kinds of photocurable materials (cyan, magenta, yellow, white, black) and support materials with the initial alignment setup is used. A standard pattern is printed and the image is captured by a scanner. A visual processing algorithm is used to calculate the characteristics of the printed image. The image operation is performed and the offset parameters required for the system alignment are obtained. This study proposes an automated approach for multi-piezoelectric heads alignment which may reduce the time required for manual calibration and the alignment error. It improves the printing quality for a 3D printing system with multiple nozzles after the alignment process.

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