Construction Improvements for the Making of Free-Form Surfaces

• Main Authors: Chen, Tzu-Hao, 陳子豪
• Other Authors: Liu, Y. T.
• Format: Others
• Language: zh-TW
• Published: 2010
• Online Access: http://ndltd.ncl.edu.tw/handle/21736323151808786727

碩士 === 國立交通大學 === 建築研究所 === 99 === The development of computer technology and new media in architecture has given new rise to the creativity of designers and lead architecture to new break through in construction. The making of CAD/CAM free-form structures, can be divided into the making of curved surfaces and the skeleton. In using curved glass as the skin, methods often used are: 1. CNC for the making of curved components (Kolarevic, 2003) 2. Triangulating curved faces and then flattening (Welch, 1994; Turkiyyah, 1997; Lee,2005) 3. Quadrilateral Planar Facets. (Glyph , J.2002;Shelden, 2002 ;Schmiedhofer,2008) This research paper proposes a new method for curved-glass construction using a simple and robust geometric method.Presently, problems encountered while making CAD/CAM surfaces are view in two dimensions: 1. Manufacturing issues: In present manufacturing, each unit is unique and needs to be made individually. Such complexity leads to problems like mounted expenses and difficulties in construction. ( LIM , 2006 ;Lee,2005 Turkiyyah ,1997) 2. Aesthetic issues: Triangulating , and parallelogram framing techniques form shapes out of planar components. This constructs a non-smooth surface for the exterior causing it lose aesthetic values. ( Shelden,2002 ;Schmiedhofer,2008 ;Baldassini,2008)Therefore, the main problem is: in order to minimize changing the original design during construction and to construct in a simpler fashion, how do we maximize the amount of repeated components but at the same time keep the smoothness of the free form design? According to the problems mentioned above, we review actual cases on curtain glass, and then demonstrate the geometric method through procedure. At the end process and steps will be categorized and organized into a framework for free-form glass dividend. Free-form surfaces mentioned in this paper are to meet the restrictions: 1. free-form surface must be a glass curtain 2. curved surface must be curved in both directions. 3. the surface component is to be a curved surface which has a constant radius of curvature. The geometric method proposed in this research, uses a curved surface to meet the original designed shape allowing surface components to divide surfaces into repeated components. Procedure can organized as below: Step 1:To use a double dimension (U,Vdimension) degree 2 curve as a control element for NURBS. Step 2:By adjusting the control element we execute form-finding on the “ main 3D model”for a shape-closure to the original form. The new shape will come close to the original and thus replace it. Step 3:Then, divid the curved surface to while conforming these two control elements. Step 4:Part of the new curved component will grow symmetrically due the the symmetry of the curved line. Resulting from this symmetric, paired and identical curved components will be found in the new shape. The new surface constructed using this method will result in a smooth surface along with a few repeated curved components. However, this inevitably will slightly change the shape of the original design. Under ideal circumstances, curved components can be reduced to half the original design.