近幾年來，三維(3D)列印已經成為現今研究中的熱門發展領域。根據不同的使用目的，三維(3D)列印已經應用於許多不同的領域之中；例如軍事、工業、汽車、醫療、藝術、食物等等。三維(3D)列印是一種製造過程，它將電腦中的數位結構資訊經過轉換後，製作成真實的三維(3D)立體結構。最常見的三維(3D)列印製成可分為三類，擠出成型，顆粒堆積成型，以及光聚合成型。適用於三維(3D)列印的材料有相當多，從熱塑性塑料，橡膠，矽酮，金屬，熱塑性塑料粉末到光敏聚合物等皆可做為三維(3D)列印的使用材料。

本篇論文的研究領域屬於擠出成型的三維(3D)列印技術，主要是在探討由出成型的三維(3D)列印技術製作而成的物體，其結構裡的網格型態、網格密度與結構強度之間的關係。擠壓成型的三維(3D)列印技術是將物體的三維結構經過水平切片後，將這些片狀結構用擠出列印的方式製造出來後，再將片狀結構堆積起來的一種製成方法，透過填充特定的網格型態進入內部結構，可間接影響物體結構的完整性。本篇論文透過數值模擬的方法來研究數種內部網格型態與物體結構強度的關係，透過自行架設之機台來印製進行模擬的物體原型，用此三維(3D)模型進行實驗的方式來相互驗證。本篇論文之結果可提供給日後使用三維(3D)列印的工程師一個判斷準則，當需要印製物體結構時，透過內部網格型態與物體結構強度的關係探討，使工程師能選擇最適合的內部網格型態及密度來印製所需之物體結構已達到所需的結構強度。

The usage of 3D printing has become very popular in recent years due to its usefulness. Depending on the applicable purpose, it has been applied in many sectors; such as military, industrial, automotive, medical, art, food, etc. 3D printing is the process of making three-dimensional objects from a digital source into real physical products. The three most common types of 3D printer are extrusion type, granular type, and light polymerised type. Flexible varieties of material those can be used for 3D printing are ranging from thermoplastics, rubber, silicone, metal, thermoplastic powders to photopolymers.

The scope of this thesis covers 3D printing with extrusion type and the results from implementing many different infill pattern strategies. 3D printer with extrusion type creates an object by slicing it into many stacked horizontal layers and uses infill to provide structural integrity by filling the internal section of an object in particular pattern. Proposed results were based upon qualitative research method combining simulation, mechatronic integration, and experimental verification to investigate how the different shapes of pattern and infill densities in the internal structure would affect the strength of the model. The result will offer additional knowledge for design engineer on selecting infill pattern to achieve optimum mechanical properties.

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