SCIENCE with RICHARD FENNING
Although I’ve been assured,
while talking to the two
heads of CCNR, Michael
O’Shea and Phil Husbands, that a
Matrix-style robot takeover is not
on the cards, a movie of a line of
robots is making me feel slightly
uneasy. As we watch three boxes on
wheels doing a geriatric conga
across a lab floor, I want to ask
have you never seen Terminator?
Do you really want to be visited by
an angry John Connor and his seven
foot tall Austrian cyborg?’
The reason for my paranoia is that
they have organised themselves into a
moving line - one robot taking the role
of leader and the other two following
- without any prompting or sophisticated
communication between them;
only four infra red sensors each. When
they reach a wall, they swap roles, and
start in the opposite direction. They
can do this because their brains have
evolved that way; no engineer with a
blank piece of paper could have done
a better job.
So, how do you go about evolving
robot brains? Imagine a load of points
connected up randomly with wires.
The way in which they are connected
can be represented as a string of information
(see the first part of the picture)
in much the same way as you can represent
genes. Create thousands of
these and you have an initial artificial
gene pool. You have to test each one
for the ability to perform a certain task;
say move towards an object that looks
like a box on wheels (there are far too
many genes to really do this, so it’s all
simulated on a computer). Kill off the
most useless - a sort of un-natural natural
selection - and chop up and mix
all the genes that are left. You then
have to mutate a small amount of the
information, swapping zeros for ones
and vice versa for about 4 bits in 500
it is interesting that this is absolutely
essential to the evolutionary process -
it can only be explained if you think of
evolution as a ‘fitness landscape’ with
hills valleys and plateaux, rather than
any misleading notion of a linear
march towards perfection. The mutations
can be thought of as the gene
pool feeling around the local area for
any nearby hills). Repeat this for about
10,000 generations and the robots are
ready.
The power of this process is such
that it can be used for all sorts of
things from designing computers to
aircraft wings; anything where there
are too many changeable parts (like
robot brains), or where you have too
much chaos (like the flow of air over a
wing). One area in CCNR is concerned
with evolving circuits in a special type
of silicone without modelling it on a
computer first. This has given birth to
parts of circuits that seem to have no
point, but turn out to be essential
when removed. The process can feel its
way round properties of the silicone
that are unknown to the experimenters!
CCNR works at the cross-over
between biology, psychology, electronics
and IT. Taking inspiration from biological
systems, it strives to create ‘simple
autonomous intelligent machines’
which can be used in inhospitable
places, such as nuclear reactors or the
surface of Mars (part of the funding
comes from the British Space Centre).
There are teams looking at a diverse
range of areas from; how insects can
learn and re-learn landmarks to guide
them through changing landscapes; to
modelling the brain as an ever changing
chemical machine; and as already
indicated, evolutionary theory.
Knowledge works both ways;
modeling natural systems brings
invaluable insights into the workings of
them. Why have animals never evolved
wheels? How do insects not get lost?
How has the complex interplay of
chemicals and electric pulses that are
our brains come about? These are
things that CCNR is interested in.
But what about the enslavement of
the human race? Phil Husbands reassures
me that the shuffling procession
on the screen ‘can only be described as
life in a very philosophically pedantic
way’, and that the next step is to
‘make the robots move things, learn
and re-learn landmarks - interact with
their surroundings’. I wonder if the
robots see it that way.
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