雙光子聚合微加工之產品模型建立與模擬

Product Model Creation and Simulation for Two-photon Polymerization Micro-manufacturing

廖昭仰(Chao-Yaug Liao)

指導教授 ： 鍾添東 ； Jean-Claude L&eacute ； on

國立臺灣大學/工學院/機械工程學研究所/博士(2008年)

https://doi.org/10.6342/NTU.2008.01112

摘要

近幾年來，一種由雙光子吸收理論衍生出的雙光子聚合(TPP)微加工技術，因具有製造任意形狀且複雜之三維微結構的能力而逐漸受到矚目。觀察目前的研究，其趨勢已逐漸從製造最小可能特徵來擴展應用領域層面，轉變成針對提高其製造良率與/或效率等較實用方面上。本論文從電腦輔助設計/電腦輔助製造(CAD/CAM)的觀點，提出一個基於TPP微加工技術之微產品模型建立與模擬的完整解決方案。
在進行TPP的製造特性分析及考量微結構外型限制與功能需求之後，其結果顯示出此類物品的數位模型需要能表示出non-manifold拓樸結構的特徵。考量上述需求及指出目前缺乏實用軟體的現實之下，對於那些創造於設計室的產品，本文提出一套non-manifold模型準備方案。將來自於STEP檔案的CAD模型予以網格化後，再用數個多面體次區域來構成一個non-manifold模型。至於若產品已存在的話，其數位模型可以使用逆向工程技術得到。然而目前絕大部分目前所使用的方法只重建了物品外型而未還原其本身顏色。因此，本文提出一套可重建三維彩色模型之整合掃瞄程序。
為避免因過度聚合導致產生的微結構毀壞及因反射率不同導致聚合體大小不一，在藉助三維製造設備的幫助下，本文分別發展出一套雙維切層方法及專屬的雷射掃瞄路徑之規劃程序。上述兩方法同時亦可以增加加工效率。此外為加強微結構的強度，本文以焊接與雙輪廓概念發展出兩種方法，用來強化各次區域之連接強度與增加結構壁厚。
最後，數個數位微結構(包含non-manifold結構)以本文所提出方法實際用TPP微加工技術製造出來，來展示本論文所提出的方法之效能。

關鍵字

微加工 ； 雙光子吸收聚合 ； non-manifold物品 ； 二維切層 ； 三維彩色模型重建 ； 層加工 ； 逆向工程

並列摘要

Recently, the Two-Photon Polymerization (TPP) micro-manufacturing technology derived from two-photon absorption draws everyone’s attention because of its fabrication capability of arbitrary-shaped and complex three dimensional (3D) microstructures. According to my observation of current researches, the trends have gradually changed from fabricating smallest possible features to expanding its application domains toward more effective topics such as increasing fabrication quality and/or efficiency. This thesis proposes a micro-product model creation and simulation scheme for TPP micro-manufacturing from Computer-Aided Design/Computer-Aided Manufacturing (CAD/CAM) points of view.
An analysis of TPP main features is performed to characterize its manufacturing capabilities. According to the analysis results and the incorporation of microstructure shape constraints and functional requirements, it is shown that the digital model of such objects should be able to describe non-manifold topological structure. Taking this requirement into account and pointing out the lacks of current practices, a non-manifold model preparation scheme is proposed for a product created at a design office. The CAD model imported from a STEP file is tessellated into several manifold polyhedral sub-domains forming a non-manifold polyhedron. Similarly, for an existing product, it can be reverse engineered to obtain its digital model. However, most of current approaches only reconstruct the object shape without its intrinsic colors. For this reason, an integrated scanning process is developed in this thesis in order to generate 3D colored models.
To avoid the destruction of the microstructure caused by over polymerization and the inconsistent voxel sizes originated by variations of light reflections, a two-dimensional slicing process and a dedicated trajectory path planning are developed with the aid of the 3D capabilities of the manufacturing equipment. Hence, the fabrication efficiency can be increased by applying the two processes above. In addition, to improve the microstructure stiffness, two methods developed through the concepts of welding and double contours are used to strengthen the connections between sub-domains and increase their wall thickness, respectively.
Finally, to demonstrate the efficiency of the proposed approach, several digital microstructures, including non-manifold ones, are fabricated according to the proposed model preparation and processing scheme.

並列關鍵字

Micro-manufacturing ； Two-photon polymerization ； Non-manifold objects ； Two dimensional slicing ； 3D color model reconstruction ； Layered manufacturing ； Reserve engineering

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