分割不可脫模之薄殼物件成為數個可脫模物件

Dividing A Non-mouldable Thin-shell Object into Mouldable Pieces

馮煒良(Wai-Leong Fung)

指導教授 ： 陳漢明

國立臺灣大學/工學院/機械工程學研究所/碩士(2005年)

https://doi.org/10.6342/NTU.2005.01084

摘要

在生產過程中，有一些物件，既不能以兩片公母模來製造，亦不能用多片模塊來生產，就稱之為不可脫模物件。為了製造這一類不可脫模的物件，就必須先把其分割，使其每一片都能製造。為此我們提供了一個方法，根據可脫模性和可視性，把被定義為不可脫模的薄殼物件，分割為數個可脫模物件，而每一個分割出來的物件都能被傳統的兩片公母模所製造。本研究中我們所採用的是三角網格的模型，而輸出則是一些三角網格群組。
本研究中所提出的方法主要由兩個部份所組成。第一個部份論述水平切割的方法。物件沿ｚ軸被數個水平面所切割使得每一個切割面都得到一個輪廓。然後分析每一個切割面的輪廓，再經過本研究所提出的一個合併方法，得到了脫模方向集合。第二個部份則介紹一個切割物件的方法，利用第一個部份所得的脫模方向集合，把物件切割為數個可脫模部份。

關鍵字

脫模方向 ； 可脫模性 ； 脫模範圍

並列摘要

In the manufacturing process, some objects, which cannot be produced either by two-piece or multi-piece moulds, are considered as non-mouldable. An additional disassembly process to these objects should be introduced in order to make these objects manufacturable. This thesis describes a method to divide a non-mouldable thin-shell object into several mouldable pieces suitable for traditional two-piece moulding based on the surface visibility and mouldability. Triangle facet model is used in this method and the output result is a set of triangle facets.
The proposed method is composed of two steps. In the first step, the object is sliced horizontally along the Z direction and a set of two-dimensional contours is obtained. Each slice is then analyzed and a set of parting directions of the object is determined with the proposed combining method. Afterwards, the object is sub-divided into several pieces according to their corresponding parting directions in the last step.

並列關鍵字

parting direction ； mouldability ； parting range

參考文獻

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