@UPE – Dynamorphe 2021 – F. Chameroy & L. Demont

Polydon is a deployable-inflatable structure that expands or retracts by folding. Dynamorphe has previously investigated interactive deployable-inflatable structures with Diodon, using Ron Resch 1973 triangular deployable origami pattern. The present pavilion investigates non-developable deployable membranes by reinterpreting prior art by Kovacs 2004 exploring mechanics of bar-hinge expandable polyhedral structures.

Facts and figures

  • Dimensions: From 3.8 to 4.7m large.
  • Material:  Flexible sheet membrane, FRC rods, synthetic rope, metal frame support.
  • Overall weight : 175kg, membrane weight : 25kg.
  • List of people involved: Léo Demont, Félix Chameroy, Clara Chotil, Nicolas Leduc, Cyril Douthe.
  • List of partners (industrial and academics): Dynamorphe, Navier Laboratory, Université Paris-Est, Diatex, Assemblage Tubulaire.

Description of design strategy

Starting from a regular dodecahedron, Polydon has been added folded tucks and adapted to fit architectural and fabrication constraints. The base face is enlarged to improve spatial comfort, and the folding pattern is optimized for developability and facet planarity. Figure shows how the deployable membrane (1) is pressured by a fan (3) and a rope-pulley system (2) allows to adjust the membrane’s shape by pulling fold vertices.

Detailing

To make a plate foldable, it is necessary to provide folds, that is, some gradient of stiffness following lines or curves. Here, the base membrane is a very flexible sheet material, which is locally rigidified at fold lines by FRP rods fastened into sewed sleeves.

Former project by Dynamorph: Diodon

Relevant references

Kovács, F., T. Tarnai, P. W. Fowler, and S. D. Guest (2004, February). A class of expandable polyhedral structures. International Journal of Solids and Structures 41(3), 1119–1137.
Resch, R. D. (1973, June). The topological design of sculptural and architectural systems. In Proceedings of the June 4-8, 1973, National Computer Conference, AFIPS ’73, New York, NY, USA, pp. 643–650. Association for Computing Machinery.