In reference to economy of materials, rapid deployment, self sufficiency, interactivity and leave no trace aspects of the ten day Burning Man Festival in the Nevada desert I have explored vacuumatically prestressed structures (vacuumatics) to create a temporary structure.
Using minimal materials, a Balloonwrap cloud would encourage maximum participation during the construction and throughout the festival. An ephemeral soft cloud like landscape, where participants delight in modifying the shape as well as being able to interact with the structure by lying down, dancing on, climbing and sitting inside the enclosure.
As documented in the film above, Balloonwrap is a vacuumatic structure made using Polythene sheets at 63 microns, 5m x 3.65m, with balloons as the filling. A large scale model here is made rigid enough to span gaps, flexible enough to bend back on itself and strong enough to act as a seat or even a bed.
The material could therefore be used as the floor, wall, roof and seating elements in a continuous loop for any installation with the added benefit that it would have good thermal insulation as well as solar reflective potential (using silver/white reflective balloons/opaque film).
The main advantages of Balloonwrap are form flexibility and adaptability. An important factor that determines its adaptability is the flexibility control. Without any negative pressure (0% vacuum) the balloons inside the polythene enclosure possess hardly any consistency and are able to flow freely inside this skin. By increasing the amount of vacuum pressure the consistency of the balloons gradually increases, resulting in a more or less plastic behaviour of the structure. This enables the structure to be shaped while keeping its newly given form. Finally, in fully deflated state (100% vacuum) the Balloonwrap becomes rigid, with balloons used as a filling in my experiments, it is possible to climb the rigid load-bearing structure and sit comfortably! The reversibility of this rigidifying process enables the Balloonwrap to be re-shaped all over again.
This animation shows a model made from modular magnetic tetrahedra. Each tetrahedron has a side length of 50mm, and contains four spherical neodymium magnets.
The tetrahedra build up according to rules that stem from their dihedral angle [angle between two faces]. The dihedral angle of a tetrahedron given by θ=arccos(1/3) [approx 70.5288°]. This means that five tetrahedra placed face to face around a single axis fall approximately 7.2° short of a full 360°. Because of this, the tetrahedra do not fill space, and instead form sections of helical structures called Boerdijk–Coxeter Helices [Named ‘Tetrahelices’ by Buckminster Fuller].
The magnets in the tetrahedra ensure that when placed by hand, they lock together face to face to form structures that completely follow these rules. When pushed just within range of the magnets of other tetrahedra, they exhibit self organising properties, but due to the power of the magnets, occasionally stick edge to edge or vertex to vertex instead of face to face.