How to weave a perfect sphere with curved strips

ORAL

Abstract

Triaxial weaving, a craft technique that enables the generation of surfaces with tri-directional arrays of initially straight elastic strips, has long been loved by basket makers and artists seeking a combination of practical and aesthetically-pleasing structures. The design principles of traditional weaving are based on the observation that the non-hexagonal topology of unit cells imparts out-of-plane shapes. In the realm of differential geometry, the weaving tradition is rooted in the concept of Euler characteristics through the Gauss-Bonnet theorem, with discrete topological defects being used as building blocks. Taking an alternative point of departure, we introduce a novel approach for triaxial weaving that enables us to continuously span a variety of 3D shapes of the weave by tuning the natural in-plane curvature of the strips. We systematically explore the validity of the new strategy by quantifying the shape of experimental specimens with X-ray tomography in combination with continuum-based simulations. To demonstrate the potential of our design scheme, and as a canonical example, we present a fullerene-like weave that is perfectly spherical, which cannot be readily achieved using straight strips. Ellipsoidal and toroidal structures are also explored.

Presenters

  • Changyeob Baek

    • Department of Mechanical Engineering, Massachusetts Institute of Technology
    • Department of Mechanical Engineering, Massachusetts Institute of Technology, USA
    • Massachusetts Institute of Technology

Authors

  • Changyeob Baek

    • Department of Mechanical Engineering, Massachusetts Institute of Technology
    • Department of Mechanical Engineering, Massachusetts Institute of Technology, USA
    • Massachusetts Institute of Technology
  • Alison G Martin

    • Italy, Independent artist
  • Tian Chen

    • Institute of Mechanical Engineering, École Polytechnique Fédérale de Lausanne
    • School of Engineering, and School of Computer and Communication Sciences, Ecole polytechnique federale de Lausanne
    • FlexLab, Ecole Polytechnique Federale de Lausanne
  • Samuel Poincloux

    • Institute of Mechanical Engineering, École Polytechnique Fédérale de Lausanne
    • FlexLab, Ecole Polytechnique Federale de Lausanne
  • Yingying Ren

    • School of Computer and Communication Sciences, École Polytechnique Fédérale de Lausanne
  • Julian Panetta

    • School of Computer and Communication Sciences, École Polytechnique Fédérale de Lausanne
  • Mark Pauly

    • School of Computer and Communication Sciences, École Polytechnique Fédérale de Lausanne
    • School of Computer and Communication Sciences, Ecole polytechnique federale de Lausanne
  • Pedro Reis

    • Institute of Mechanical Engineering, École Polytechnique Fédérale de Lausanne
    • School of Engineering, Ecole polytechnique federale de Lausanne
    • Ecole Polytechnique Federale de Lausanne
    • École polytechnique fédérale de Lausanne
    • Flexible Structures Laboratory, Institute of Mechanical Engineering, École Polytechnique Fédérale de Lausanne (EPFL), Switzerland
    • FlexLab, Ecole Polytechnique Federale de Lausanne