SPINNING THE WEB OF A STRUCTURE

摘要

n November 2012 the Institute for Computational Design (ICD) and the Institute of Building Structures and Structural Design (ITKE) at the University of Stuttgart, led by Professors Achim Menges and Jan Knippers, completed the fabrication and installation of a unique fiber-woven pavilion. Strikingly beautiful from a distance, the pavilion's true innovation comes into focus through examination of its digitally woven skin. The pavilion stands at about 3.5m tall and 8m in diameter, yet it weighs less than 320kg and measures just 4mm thick. It is the product of ongoing research collaboration between architects, engineers, biologists and students. As a precedent, the team examined lobster exoskeletons, specifically focusing on material differentiation along the cross-section of the organism's shell. Variation in stresses placed on the shell cause its microscopic fibers to migrate from parallel to perpendicular orientation. In the pavilion, similar changes in fiber orientation efficiently accommodate the flow of forces through the structure. The resulting pattern of layered strands in the shell forms a visual map of those forces flowing through its surface. The research team relied on a six-axis robotic arm to accurately weave the resin-saturated carbon and glass fibers together. A temporary steel frame formed an armature across which fibers were stretched while being woven. To protect it from the weather, the frame sat on a rotating platform in a provisional structure near the site of the pavilion. As the frame rotated slowly on its turntable, the robotic arm went to work laying down more than 30km of fiber. Successive layers of fiber strands are clearly visible in the resulting translucent material assembly. Once the fabrication of the pavilion was completed, its steel frame was removed and it was carried to its final resting place not with heavy cranes or lifts, but with a small group of students each supporting one of its legs.