FIGURE 1. Dr. Walter working on a later version of Elmer.
High-power density and lightweight LiPoly batteries,
efficient H-bridge power controllers for our robot’s motors,
and a vast number of sophisticated sensors are available to
us today that would have amazed scientists 50 years ago.
GPS, RF links, LEDs, finger-sized HD color cameras, laser
navigation, and that one thing that made small robots so
easy to build — the model aircraft servo — all added to the
mother lode that enhanced experimenter’s robot building.
Add to that the many microcontrollers and inexpensive
microprocessor-based computers and one can build some
remarkable robotic devices.
Homebrew Robotics
There is one main attribute that sets experimental and
hobbyist robotics apart from the typical computer user or
even hacker activities and that is the homebrew aspect.
Robot hobbyists like to build things with their hands, not
just plug some module into their computer and write a
hundred lines of code for it. Yes, code is important for any
smart robot but interfacing different motors, sensors and
feedback devices with the ‘brain’ is what makes robotics
so interesting. Designing appendages and joints, accurate
placement of the sensors, weight and balance, and power
requirements all come into play to make robot building
so rewarding.
Early Robot Experimenters
Going back six decades, in 1948 to 1949, Englishman
William Grey Walter built two phototropic (light seeking)
robot turtles. The most famous one he called Elsie as it had
a clear shell, unlike his earlier Elmer that used strips of
folded tin to replicate a shell. Figure 1 shows Walter’s lab
and an improved Elmer. It is quite interesting to read what
a newspaper said about the earlier Elmer: “LONDON. Feb.
25, 1948. The Daily Express reported today that Dr. W. Grey
Walter, 38 year old brain scientist, has built a robot tortoise
so human that it likes company, recognizes voices, and
comes to heel when called. The paper said that the tortoise
avoids cold or damp weather, great heat or bright lights,
likes women but dislikes men. “It can be temperamental
and will be neurotic and sulky for days if teased or given
too many contradictory instructions.” Dr. Walter, at the
Burden Neurological Institute in Bristol, England, built the
tortoise with ordinary radio valves (tubes), switch relays,
miniature microphones for registering sound, and
photoelectric cells for recognizing color and shape.” (That
sounds even better than Sony’s Aibo!) This type of hype
was typical for any new fangled gadget that made the
headlines in those days. The news media made it sound so
much better than reality.
As a neurophysicist, Walter was interested in
conditioned responses and needed a ‘tool’ to exhibit these
Amazing Robots Arise From Junk
FIGURE 2. The Bristol Tortoise.
responses while working at the Burden Neurological
Institute. Walter’s original robots — built with the help of his
wife, Vivian — were dismantled and the various parts were
used in improved models. Only photographs remain, though
personnel of the BNI built several replicas. Figure 2 shows
of an accurate replica called the Bristol Tortoise, though the
motors are of a more modern variety. His machines were
considered the first true robots and many people copied
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