

Overview of the BioCube
21^{st}
century computing will be performed on machines constructed by assembling atoms or molecules
with nanotechnology tools at the nanometer scale. The BioCube, developed at the Ecole Polytechnique
Fédérale de Lausanne (EPFL), is a prototype that embodies the operating principles of such a machine,
blown up a billion times. It is organized as a cube of 4x4x4=64 nodes, where each node consists of a
processor implemented by a programmable logic circuit (FPGA = FieldProgrammable Gate Array).
The complete BioCube foreshadows a threedimensional nanocomputer, where each node will
be realized by a group of atoms, a molecule.
Reduced to the microscopic dimensions of an array of molecules,
the nanocomputer will feature some of the properties of living organisms, such as selfrepair. Extremely robust,
it will be exploited wherever reliability is crucial. In space, it will become an indispensable tool for automatic
probes; on Earth, it will allow the development of systems capable of operating even if their atomicscale components
become momentarily or permanently faulty.
The BioCube, in its current form, is a cube of 64
transparent spheres. Each sphere contains an electronic circuit and possesses an internal state computed
as a function of the states of the six cardinal neighbors to which the sphere is connected. This completely
homogeneous structure allows the direct implementation of threedimensional cellular automata: a 3D version
of the "Game of Life" will be among the first applications to be developed on the BioCube, together with
several variants of selfreplicating cubes. These last will open the way to the realization of threedimensional
artificial organisms whose structure, inspired by biological systems, will allow them to grow through cellular
division and differentiation, to selfrepair, and to selfreplicate.
Ressources
