摘 要

由實體表面所取得之點資料建構CAD模型的過程稱之為逆向工程，實體(又稱原型)通常是由經驗豐富且具創意的造型專家所製作，再由工程師以逆向工程建構實體CAD模型。逆向工程的設計理念非常適合用於以自由曲面為主的產品，許多消費性產品皆逐漸重視以逆向工程為主的產品設計方式，本研究針對逆向工程重建CAD模型的過程作整體的研究，並以數位萬用電表、高爾夫球頭及殘肢模型作為實例，使用專業逆向工程軟體Surfacer詳細地示範逆向工程重建CAD模型的過程。
逆向工程主要的步驟包含點資料取得、點資料合併、點資料區域分割、曲線建構、曲面建構及誤差分析。本研究對這些步驟所提供的解決方法分別為以雷射掃瞄量測儀取得點資料，搭配Polyworks軟體作點資料合併，其餘的步驟則是在Surfacer軟體中進行。

Abstract

The process of obtaining scanned points from a physical object using a laser scanner and building its CAD model is called as reverse engineering. Reverse engineering is an appropriate method for designing product with free-form shapes, and recently many industries use reverse engineering method to design new products. The main procedure of reverse engineering involves steps of data points acquisition, multiple view data points registration, data points segmentation, curve fitting, surface fitting and error analysis. In this study, a laser scanner is used to capture data points from objects, a commercial software-Polyworks to merge multiple view data points, and a reverse engineering software, i.e. Surfacer, to manipulate other steps.
This research is a study of constructing CAD models. Three physical objects, i.e. electric meter, golf head and residual limb, are employed to demonstrate the process of CAD models generation based on their scanned points.

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