手繪草圖的空間詮釋－利用程式與快速成型

Abstract

手繪草圖常被使用在概念設計過程中；其特點在於其能在短時間內不斷塗改和不準確線條所給予設計過程中的曖昧性，設計者並能從手繪草圖得到視覺的回饋並對設計進行重新詮釋的過程（Schon and Wiggins, 1992）。然而由於電腦輔助設計（Computer-Aided Design, CAD）和電腦輔助製造（Computer-Aided manufacture, CAM）的設計環境大多講究線條與形體的準確性，電腦輔助的設計過程多只能應用在設計過程中較後期的階段（Gross, 1996）。為了突破這個困境，有研究者提出在電腦輔助設計環境中利用筆式的輸入方式進行手繪草圖（Gross, 1996; Igarashi, Matsuoka and Tanaka, 1999; Do, 2001; Jung, Gross and Do, 2001）。另一方面，在電腦輔助設計環境中透過建模的（modeled）、程式運算的（programmed）和相片推導的（image derived）等方式所得到的數位模型可以直接被輸出為實體模型（Kai and Russell, 2005）。 本研究強調對手繪草圖空間詮釋的重要性，探討突破電腦輔助環境中繁複的操作程序，發展出對手繪草圖進行空間詮釋並以電腦運算方式生產實體模型的系統原型Spatial Charcoal。設計者只需要在紙上或以筆式作手繪草圖，草圖經由掃瞄器進入數位資料後會進行空間詮釋並建立數位模型，便能作為概念實體模型輸出RP模型。 本研究主要分為三個部分：第一部分對建築師的手繪草圖進行分析，主要針對手繪草圖的註釋方法進行分析與建構；第二部分為系統的設計與實作，以及案例操作示範。第三部分為使用者測試與評估。 本研究讓不同設計者以個人的手繪草圖方式進行空間詮釋，系統可以直接輸出相對應的有手繪特性的概念模型。結果說明了設計者在簡單的熟悉整個的設計過程後，便由於操作經驗所驅使下回饋到手繪草圖上，對繪畫線條與深淺等作出修正的控制而做出他們想要的實體概念模型。本研究的貢獻提供方便的轉換方式，強調空間詮釋的可能性，取代了以往為了輸出數位形體而費力學習建模的設計過程。設計者可以在概念的時期將手繪草圖作為想像中實體手繪式模型操作，同時加強了設計者對手繪草圖時立體形體的想像。

Freehand sketch is always been using in conceptual design process, its characteristics help designers alter the contour constantly within short time, designers can derive some visual feedback from the sketch and then reinterprets the design (Schon & Wiggins 1992). While drawing in the computer-aided design (CAD) and computer-aided manufacture (CAM) environment, elements must be identified specifically, positioned and sized precisely and that can only be used in the later process of design (Gross 1996). In order to break through this predicament, researchers propose utilizing the pen-based system to sketch in CAD environment (Gross 1996; Igarashi, Matsuoka & Tanaka 1999; Do 2001; Jung, Gross & Do 2001). On the other hand, designers could generate digital model by modeling, programming and image deriving in the CAD environment and then fabricate it on a computer numerically controlled (CNC) machine (Kai & Russell 2005). With emphasizing the importance of spatial interpretation of freehand sketches, the objective of this research aims to simplify the inconvenient and complicated operation sequence in the current CAD environment; developing a system prototype, Spatial Charcoal, that generates entity model by a program which translates the spatial interpretation of the freehand sketch into a 3D digital model. Designers draw sketch on paper, and then scan it, or draw sketch directly on the computer pen-based system. This digital data is spatially interpreted and generate a digital model, which will then be fabricated to an entity model in RP machine. The research is mainly consisted of three parts: First, analyzing famous architects’ sketches mainly builds up a spatial interpretation method of freehand sketch. Second, implementing system that demonstrates different cases. Third, evaluating user testes. After designers get familiar with the design process gradually, designers’ operation experience prompts the feedback on sketching, and then they modify the ways of drawing lines and darkness to master the entity conceptual models. The significance of the research provides a convenient conceptual design process, which emphasizes the probability of spatial interpretation and replaces the past laborious work of modeling digital model. Furthermore, designers can modify the entity sketchy model by sketching and that strengthens designers’ imagination of three-dimensional physique while sketching.