150,000 cells or more. The neurons
begin to form interconnections within
20 minutes and establish an elaborate
network within a week after the
growth starts.
Gordon has a suite of four pairs
of ultrasonic transducers to detect
obstacles — the same Devantech
SRF08 ultrasonic rangefinder modules
many robot experimenters use on
typical robots. The modules are
pinged every 250 ms and map the
room in much the same way as
maze-running robots.
What is more unique is that the
cell mass acts as a simple brain and
is able to learn the boundaries of its
pen and not repeatedly bang into the
walls. Yes, the sonar units locate walls
and other boundaries, but the brain
actually decides what is possible to
traverse and what is not, or where the
walls are and are not. This learning
process is accomplished with just a
small mass of neuronal cells.
Starting out with a new batch of
cells, the robot may bang into the
enclosure’s walls every minute or so,
but after a few weeks, Gordon avoids
the walls entirely. After two hours of
controlling Gordon, the brain must be
placed back in a warm incubator for a
while; the lessons learned are still
retained. The brains live for about
three months before becoming
inactive through aging, as the needed
voltage stimulation becomes too high
to be effective. Warwick hopes to add
speech recognition
inputs so the robot
can go right or left on
spoken command.
and vision systems for the little robots
to be useful for any tasks.
FIGURE 3. Fraunhofer-Institut
camera pill.
not have the number of active
neurons of animal brains, but
they have over a hundred million
transistors. Simple Flash drives the size
of your fingernail have the equivalent
of many billions of transistors. The
complexity of these chips would have
been unthinkable in the 1960's.
Processing power of this magnitude
would have been a robot designer's
dream. Even today's less complex
microcontrollers have astounding
'power' compared with earlier robot
circuits and they control 95% of
experimental robots built these days.
Nanobots are the dreams of
doctors and experimenters worldwide.
They are perceived to be so small that
their very bodies are not much larger
than individual memory cells in chips
or sub-nanometer discrete transistors.
With this in mind, future nanobots
must rely on even more microscopic
circuitry than is available today to
have any sort of intelligence, and
even this does not allow for
propulsion and steering motors,
sensors, manipulators, programming,
The Need for
Smaller Robots
Back in 1966, the premise of the
film Fantastic Voyage was that the
only way to save an important
physicist with an inoperable blood
clot in his brain was to miniaturize a
submarine and its crew, and send it
in to do the work.
Fantastic Voyage may have
seemed a bit silly to anyone with any
sort of scientific background, but it
did highlight the desire the medical
community had to want to see inside
a human body. X-rays, endoscopes,
and later CT scanners, MRI machines,
and PET scanners do allow amazing
non-invasive views of the interior of a
patient's body, but do not satisfy a
medical doctor's needs to see the
very tiniest sections of a body such as
the vascular system or the interior of
various organs.
Newer surgical instruments such
as the da Vinci Surgical Robot allow
surgeons to perform delicate surgery
with minimal invasiveness, but the
need is still there for something or
some method to allow imaging and
manipulation in very inaccessible
areas of the body. Crawling inside a
patient's body is about as possible as
sending a nano-sub with a doctor
aboard down a vein to treat a
patient's ailment.
FIGURE 4. Robot Minidoc.
FIGURE 5. Minidoc on mission to heal.
Powering
Small Robots
Mini Surgical
Assistant
Robots
Most robotics
researchers have not
used living neurons
and brain tissue as did
Warwick with his little
Gordon, but have
gone the route of
microprocessors and
microcontrollers for
control of their
experiments.
Microprocessors may
PHOTO COURTES Y OF TECHNOVELGY. COM.
PHOTO COURTES Y OF TECHNOVELGY. COM.
Pills that contain
what can be described
as a "miniature color
television station" have
been used by doctors
for several years. These
pills contain a color TV
camera, a series of LED
lights, and a transmitter
to send photos to a
recorder outside the
body. The devices can
photograph the entire
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