光度立體攝影技術運用於逆向工程的幾何重建

GEOMETRY RECONSTRUCTION FOR REVERSE ENGINEERING USING PHOTOMETRIC STEREO TECHNOLOGY

吳宗憲(Tsung-Hsien Wu)

指導教授 ： 戴兢志

大同大學/工程學院/機械工程學系所/碩士(2006年)

摘要

摘 要

傳統利用接觸式三次元量床重建幾何，由於缺乏待測物的幾何資訊，有二個關鍵性的問題：一、採用固定式量測間距的量測策略；二、無法即時將點資料作正確的測頭補正。本研究將以光度立體攝影技術為基礎，利用到傳遞類神經網路建立待測物的法線向量資料，提出一個能夠根據待測物表面的曲率變化，自動調整適當的間距、並測頭即時定向和點資料正確測頭補正的方案。由範例的驗證結果可知，結合光度立體攝影技術的量測程序可以一次完成幾何重建。

關鍵字

光度立體攝影技術 ； 倒傳遞類神經網路 ； 逆向工程

並列摘要

Abstract

There are two problems that are regard as a bottleneck in the traditional geometry reconstruction by using a coordinate measuring machine. This is because that the geometric information lacks of before the digitizing process. (1) A fixed measuring span is adopted for the measuring strategy. (2) It cannot offer radius compensation for point data correctly and immediately. A photometric stereo technology based on neural network is presented for automatic acquisition process with adaptive measuring spans as well as correct and immediate probe radius compensation according to the variations of curvature on the measured surface. Experimental results demonstrate that the integration of the acquisition process with the photometric stereo technology makes it possible to complete geometry reconstruction at a time.

並列關鍵字

Photometric Stereo Technology ； Back-Propagation Network ； Reverse Engineering

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