『服裝設計』是一個與我們日常生活息息相關的產業，藉由電腦輔助服裝設計能夠有效提昇產品開發的效率，其中3D人台串連起整個設計系統平台的開發與應用。應用曲面攤平方法展開人台上的3D曲面至2D平面是一個常見的方法，可得到用於設計和製造中的2D裁片，這使得一個符合服裝設計所需的3D人台資料是相當重要的。為達到這個目標，本研究提出此基於3D人台的電腦輔助服裝設計系統的開發，主要包含兩個部分：3D人台和曲面攤平。
在所提出的以特徵線重建3D人台曲面的系統化方法中，逆向工程方法先用於掃瞄服裝設計專業所用的人台模型，而在經由特徵線的分割後，可從掃瞄資料中萃取出代表造形特徵的網格點，接著以B-spline曲面重建整個3D人台的外形。同時，以最小能量為主的切線向量調整方法修正B-spline曲面間銜接的連續性，可提升造形曲面的品質。當這個3D人台應用到電腦輔助服裝設計系統平台上時，可以形變出不同人體尺寸的3D外形。為了從中得到設計所需的2D裁片，本研究從布料特性的觀點，提出此最小能量為主的曲面攤平方法。而在這個方法論中，3D曲面是以測地線法展開至2D平面上，然後近似隱含法能夠即時而穩定釋放網格中積累的應變能以修正其誤差。為了提高其準確度，進一步裁切網格釋放網格中的能量是相當常見的方法，這讓所得到的2D裁片自然產生有意義的裂縫。透過所建構的3D人台，許多服裝設計的技法可重現在2D裁片上，有助於提升電腦輔助服裝設計的層次。
最後，本研究以幾個案例研究說明和驗證所提方法論的可行，並將它們整合在一個發展中的電腦輔助服裝設計系統平台上，達到以同步設計方法進行產品開發。

Fashion Design is an industry closely connected to our daily life. Computer-aided fashion design can enhance the efficiency of product development, in which a 3D mannequin links the development and application of the entire design system. A typical application is that surface flattening enables 3D surface on the 3D mannequin which can be developed on the 2D platform. Besides, the obtained 2D pattern can be used in the field of design and manufacturing, thus rendering the 3D mannequin data required for fashion design appears very important. To achieve this objective, this study provides the development of a computer-aided fashion design system based on 3D mannequin, and it mainly includes two parts: 3D mannequin and surface flattening.
This study proposed a systematic method for surface reconstruction of 3D mannequins based on feature curves. First of all, the study applied reverse engineering methods to scan a mannequin model commonly used in the fashion design profession by extracting grid points that represent the shape features from the scanned data after the segmentation of the mannequin model through feature surfaces. Then, the shape of the entire 3D mannequin is reconstructed using B-spline surfaces. Simultaneously, the continuity among the connected B-spline surfaces is adjusted with tangent vector adjustment methods based on the minimum energy required for improving the quality of the shaped surfaces. When this 3D Mannequin is implemented in the computer-aided fashion design system, different size of body can create by shape morphing. Besides, this study describes surface flattening based on minimum energy methods according to the property of different fabrics. In this methodology, 3D surface is developed on the 2D platform by geodesic method, and then strain energy that has accumulated in mesh can be stably released by an approximate implicit method and revised error function. In some cases, cutting mesh to further release the energy is a common way to fix the situation and enhance the accuracy of the surface flattening, and this makes the obtained 2D pattern naturally generate significant cracks. Through the developed 3D mannequin, many techniques in fashion design can be applied to the 2D pattern; it enhances the level of computer-aided fashion design.
Finally, this research uses several case studies to illustrate and verify the feasibility of this methodology, and they is applied and integrated to the computer-aided fashion design system being developed to achieve product development using synchronous design methods.

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