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.
Below is a slideshow of our first Pin-Up (6th October 2011). Students mainly looked at two experiments from either Frei Otto or Buckminster Fuller in both digital and analogue ways. Next step: Re-visiting these experiments with your own techinques and ideas, keep up the good work DS10 !
Above: Jack Munro doing some magic with sand and holes in a box (inspired by Frei Otto)
Above: Results – Almost immediate formation of cells from the sand falling through the holes
Above: Carolyne Butler showing her first experiment based on Frei Otto’s wet wool threads system.