MetroWest Daily News.

August 28, 1999

Brandeis robots have big ideas for the future


Photo caption: A computer program capable of plucking out
structurally sound LEGO designs has been designed by Jordan
Pollack of Sudbury and Pablo Funes, Brandeis University

WALTHAM -- Evolution, until now the unchallenged domain of
living organisms, may soon become possible for robots as well. 

So say computer scientists at Brandeis University, where a
simple computer-based form of evolution -- nature's own design
strategy -- has succeeded in designing LEGO structures without
any help from humans. 

It's the first successful leap from today's computer-aided
design into the futuristic realm of fully automated design, and
the first baby step toward the artificial intelligence
community's long-standing dream of evolutionary robotics, where
robots might eventually adopt some form of evolution. 

Brandeis' Jordan Pollack of Sudbury and Pablo Funes, the
researchers who masterminded the achievement, say this trial and
error approach to designing LEGO bridges, tables and cranes lays
the groundwork for robots capable of reworking their own
hardware without any human guidance at all. 

Their work appears in the most recently published issue of the
journal "Artificial Life," and the university has filed for
patent protection on the work. 

"The necessity of allowing robots' brains and bodies to evolve
together has been around since the dawn of evolutionary
robotics," says Pollack, associate professor of computer science
at the college's Volen National Center for Complex Systems. "Our
view is that in nature there is never a brain without a body,
and that small changes to both must be made in a co-evolutionary

To make the rudimentary evolutionary hardware, Pollack and
Funes, a graduate researcher, constructed a computer program
capable of plucking out structurally sound LEGO designs from a
sea of possibilities. They then provided the program with simple
optimization goals, such as spanning a distance and carrying a
weight -- laying the groundwork for the fully automated design
of LEGO-based structures such as a two-meter bridge, a crane
capable of lifting a one-kilogram weight, and a table that could
support the same weight. 

After the computer analyzed hundreds of its own designs and spit
out the best ones, Pollack and Funes broke out their LEGO bricks
and built the structures. Almost without exception, they found
that the computer had engineered structures that were
structurally sound. 

"We're not saying these structures are engineering marvels, but
we've shown that even a simple evolutionary program, paired with
the right physics, can design complex structures without any
engineering expertise from humans. A number of other researchers
have tried to evolve more impressive simulated structures, but
ours are the first to translate into reality," Pollack says. 

The computer's design success was largely a function of its
skill in evaluating the integrity of LEGO structures, which
Pollack says can be determined through the patent-pending
algorithms he and Funes developed to analyze torque in networks
of the sticky blocks. 

The program is no speed demon; it took a day and a half to
design the two-meter bridge. But the cantilevered design it
eventually came up with is, at least in Pollack's estimation,
superior for a self-supporting LEGO bridge of that size. 

"What I find most fascinating about these results," Pollack
says, " is that a very simple algorithm `discovered'
sophisticated structures that took humans many centuries to
design -- a cantilever for the bridge, and an inverted triangle
for the crane." 

The work was partially sponsored by the Office of Naval Research
and the National Science Foundation. With a new research grant
from the Defense Advanced Research Projects Administration,
members of Pollack's laboratory are now developing similar
systems that feature limited motion, which is expected to allow
fully automatic design of robot bodies and brains.