CAD/CAM基礎於逆向工程技術之研究

Study of Reverse Engineering base on CAD/CAM

宋上漢(Shang-Han Soong)

指導教授 ： 黃健生

中原大學/工學院/機械工程研究所/碩士(2002年)

https://doi.org/10.6840/cycu200200256

摘要

[摘要]
逆向工程為一種從現有的實物中或樣品模型中，重建產品CAD模型或產品複製的一種技術，本研究結合三次元量測，逆向工程曲線曲面建構及CAD/CAM系統等技術，完整的逆向工程製作流程由原始模型，量測點資料取得曲線曲面建構到複製另外一個工件之完成，以其整合三次元量測座標系統、電腦輔助設計電腦輔助製造於逆向工程上。研究中利用實體模型以三次元量測用接觸式探頭，把實體模型先規劃特徵點然後取得資料點座標值運用曲線嵌合技術，利用近似法與插補法分別建構形成不同的B-Spline曲線，將插補法所建構的曲線以及近似法所建構的曲線再建構成曲面實體模型以一套完整的逆向工程之CAD模型重建方法，建構出完整的CAD模型。使用商用Euclid-3軟體CAD/CAM系統以卡式加工法作刀具路徑規劃設定刀具型式，刀具路徑模擬切削製作成NC程式，經由RS-232C傳輸連線到CNC工具機實際執行切削加工完成，最後並將原始模型與完成品作誤差比對。

關鍵字

插補法 ； 近似法 ； 自由曲面 ； 逆向工程 ； B-Spline曲線

並列摘要

[摘要]
The reverse engineering is a novel technique which has the capability to rebuild CAD models of product or to duplicate products, based on existing objects or sample models In combining the advanced technologies of 3D measurement, curve and curved surface construction with reverse engineering and CAD/CAM system, this paper mainly addresses to the topics of how to apply reverse engineering to reconstruct curves, curved surfaces and then to complete the duplication based on prototype model and measured data points, and how to integrate the 3D measuring coordinate system and CAD/CAM skills with the reverse engineering.
In our study, we first obtain the required coordinate values of feature-pints from the solid model, measuring three dimensionally with contact probes. and then the B-Spline curves are drawn with the implementation of curve-fitting, approximation, and interpolation methods. A complete CAD model is constructed with the aid of reverse engineering for a solid model with curved surfaces which are formed by curves from approximation and interpolation.
Using the commercially accessible software Euclid-3, a NC-program can be written with the availability of CAD/CAM system, well defined tool-path, and specified tool-model. All digital information is further transferred through the RS-232C to the CNC tooling machine in order to complete the precision cuttings The last effort to be devoted will be the deviation comparison between the completed work and the original prototype model .

並列關鍵字

free form surface ； interporation ； B-Spline curve ； reverse engineering ； approximation

參考文獻

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