加工特徵的辨識與其刀具路徑的規劃

Machining feature recognition and tool-path planning.

沈柏廷(Bor-Tyng Sheen)

指導教授 ： 尤春風

國立臺灣大學/工學院/機械工程學研究所/博士(2005年)

https://doi.org/10.6342/NTU.2005.00949

摘要

本研究發展一套有效的方法來自動辨識加工特徵，處裡特徵辨識時，工件的特定位置會被剖切，剖切面與工件的表面所形成的交線做為該部位的截面輪廓，這些截面輪廓的資訊不但獨立的加工特徵可以被獲得而且干涉的加工特徵皆可被辨識出來。
割切3D工件以形成2D的口袋形模穴來產生刀具路徑時，口袋形模穴的加工便形成主要的課題。加工口袋形模穴時，可行刀具裡的最佳刀具組合一直是被探索的問題，本研究提出一套搜尋上限僅為一次的方法，此方法的快速搜尋速度足以提供CAPP及CAM使用。
做完加工特徵辨識與刀具選擇後，刀具路徑的產生是另一個重要的課題，本文提出動態刪除法，在偏置的過程中便刪除過切，降低偏置輪廓的計算數量，同時並提出極多島嶼口袋形模穴的刀具路徑產生法，處理速度快。
辨識之後的加工特徵可以作為加工排程，不同種類的刀具路徑可以自動地產生，以應付不同的工件曲面，增進切削效率。

關鍵字

特徵辨識 ； 具路徑 ； 形工件 ； 具組合 ； 腦數值控制 ； 過切

並列摘要

This study develops an effective method for identifying machining features. While recognizing features, the workpiece is sliced at some specified positions. The sectional curves of the workpiece faces and slicing plane constitute the feature profiles. Not only the isolated machining features but also the intersecting machining features can be identified by the information from these intersection profiles.
As a result of slicing a 3D part into 2D pockets for generating tool paths, pocket is the one of main tasks. When a pocket is machined, it is an issue for finding the optimal result from the feasible tools. This paper presents a method which a upper bound O( N ) is used to choose the combination of optimal cutting tools, where N is the number of feasible tools.
After the recognition of machining features, the recognized machining features can be applied for scheduling the manufacturing sequences. Different kinds of tool paths can be automatically generated for various machining features to improve the cutting efficiency.
After the recognition of machining features and the choosing of tools, the generation of tool paths becomes another issue. Many researches remove the overcutting zones after the whole raw offsets are produced. The paper proposes a dynamic method to remove overcutting zones. This dynamic method can reduce the computational time number and thus secure against the dangers of errors. Meanwhile, a methodology is offered to solve the problem of pocket multi-islands. The speed for the generation of tool paths is even faster than some commercial CAD/CAM packages.

並列關鍵字

Machining feature ； tool path ； pocket ； CAD/CAM ； CNC

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