The ETH Library added the geometric model “Bille” to its collection of scientific instruments and teaching materials.
It was presented by Gergő Almádi, one of its developers. ETH Zurich is thus the first university to possess a “Bille”.
“Bille” was developed by Gábor Domokos, Professor of Geometric Modelling at the Budapest University of Technology and Economics, together with his architecture student Gergő Almádi and Robert Dawson, professor of mathematics and St Mary’s University in Halifax, Canada. The model is a donation from Ottó Albrecht.
It is regarded as the external pagefirst known monostable tetrahedron in the world. The object has four faces—the minimum possible number for a polyhedron—and, regardless of its initial position, always returns to the same stable equilibrium. In doing so, “Bille” confirms a conjecture put forward in the 1980s by the mathematician John Horton Conway. Its development is based on a combination of mathematical analysis, simulations, structural design and experimentally developed technology. The stability is achieved through its geometry and a deliberately positioned centre of mass.
The underlying principles are of considerable interest for research into monostable structures and for potential technical applications, such as the design of planetary landers.
source: library.ethz.ch/
