|
The Gömböc: Physical Evidence of a Mathematical Theorem
The Gömböc is a round piece of clear
synthetic material with gently peaked, organic curves. It looks like a piece of
modern art. But if you tip it over, something unusual happens: it rights
itself.
It leans off to
one side, rocks to and fro as if gathering strength and then, presto, tips
itself back into a “standing” position as if by magic. It doesn’t have a hidden
counterweight inside that helps it perform this trick, like an inflatable
punching-bag doll that uses a central weight to stand upright after you strike
it.
Rather, the Gömböc is something new: it is the world’s first self-righting
object with just one stable and one unstable point of equilibrium.
The Gömböc is a result of a long mathematical
quest. In 1995, the great Russian mathematician Vladimir Arnold mused that it
would be possible to create a “mono-monostatic” object — a three-dimensional entity
that purely by its geometric form had only one possible way to balance upright.
The challenge intrigued two scientists —
Gabor Domokos and Peter Varkonyi, both of the Budapest University of Technology
and Economics. Rigorous research spanning over numerous years soon followed
before both professors understood that such a mono-monostatic object could
exist.
Presenting it as a physical demonstration proved yet a further
challenge. It soon became clear that any technology used to build the
Gömböc required high precision. Such an object with a radius of
approximately 10cm required a tolerance of less than 0.1mm.
Furthermore, both mathematicians shared the belief that the Gömböc
should be manufactured from transparent material; otherwise, the
homogeneity of the object would be hard to demonstrate.
Long
search and many trials led to the 3-D Printing Technology pioneered by
Objet Geometries. The PolyJet Technology was the only technology
providing both the required extreme precision, transparent and
homogeneous material and high reliability. “PolyJet Technology allowed
for the ideal homogenous properties during print that we were seeking.
It became clear to us this Objet was the key in successfully creating a
physical mono-monostatic object” – says Domokos. Objet also allowed for
individually marking and numerating the Gömböc. In fact, both the
serial number and the Gömböc trademark appear inside the object as thin
three-dimensional tubes, filled with support material (which has almost
identical density). “Objet was a perfect fit for us!” remarked
Domokos.
The
Gömböc is a big hit in the media: a beautiful, but rather abstract
mathematical theorem was physically demonstrated in 2007 by using
cutting-edge, state-of-art technology thanks to Objet’s PolyJet
Technolgy. This discovery generated curiosity for millions of people
worldwide. In 2007, New York Times Magazine selected the Gömböc as one
of the most interesting seventy inventions of the year; the Gömböc
homepage (www.gomboc.eu) received
so far over 4.5 million hits from 143 countries. Articles about the
Gömböc appeared in 22 languages. The Gömböc stands as a symbol of
extreme precision, sensitivity, perfection, harmony and abstract
beauty.
Yet the scientists now say that Mother Nature may have beaten
them in the race after all. They have noticed that the Gömböc closely
resembles the shell of some terrestrial tortoise species, creatures
whose round-shelled backs help them right themselves when flipped over.
“We discovered it through mathematics and built it with the help of
Objet,” Domokos notes, “but evolution got there first.”
|