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littleBits made rapid circuit prototyping possible. Our
pressure plate came together in mere minutes, freeing our
hands and minds to concentrate on building our defense
robot. So, how would the circuit kit handle being turned
into a real robot?
This concern is not meant to detract from the
awesomeness of littleBits. Anything that can make
electronics accessible and exciting to a wide swath of
tinkerers of all experience levels is awesome in our book.
This is merely an observation that could apply to any kit —
when you try to apply it to projects outside its comfort
zone, it might take a little more work. So, the real question
is whether robotics is within littleBits’ comfort zone.
littleBits excels as a circuit building platform. The
modules snap together effortlessly, and the range of
sensors and outputs mean that there are endless
combinations that can meet all of your circuit building
needs. Since our last article, numerous new examples of
the creativity of littleBits users have been featured on the
littleBits website ( littlebits.cc) — pinball contraptions, a
combination locked safe, and even a “spinning replicator”
that will copy an image sensed with a light sensor and
recreate it with a servo-operated pen sketching on a
One of the hallmarks that separate robots from sessile
circuits is the attribute of movement. Both robots and mere
circuits are often capable of receiving sensory input from
their environments and using that input to perform certain
functions. Circuits largely deal with that input in a passive
way, turning on a light or a buzzer much like our pressure
plate circuit. A circuit might culminate in some sort of
simple mechanism like a servo that waves around an
indicator or lever, but that likely doesn’t rise to the level of
what most people imagine a robot to be.
Physical mechanisms are much more central to the
popular concept of a robot. Such criteria may likely stem
from the first appearance of fictional robots, which predate
real world robots by a few decades. As you may already
know, the term “robot” was coined by Czech writer, Karel
Capek in his play R.U.R. (Rossum’s Universal Robots),
published in 1920. The word is derived from the Czech
word “robota” which refers to forced labor. Indeed, the
robots (or rather roboti, to use Capek’s plural) in the play
are used for precisely that, and they look very humanoid.
Real world robots in the sense of an electronic
autonomous creation didn’t come around until the late
1940s. Perhaps the first was the “tortoise” created by
British neuroscientist, William Grey Walter. The tortoise — so
named for its low ground clearance and half-hemispherical
shell — was a small three-wheeled device powered by an
electric motor that was equipped with some basic sensors
for tasks like obstacle avoidance. It wasn’t much like
Capek’s roboti, but it does share a crucial characteristic with
what we consider a real deal robot: It moved around and
The tortoise’s mechanism was a simple drive train.
Could we imbue the littleBits with mechanical movement?
Last time with the littleBits, we had done some exploration
with what kind of mechanisms were possible with the kit.
We made a simple arm with three degrees of freedom that
was controlled through buttons and dimmers. So, what
about a driving platform like we envisioned for the present
Setting out to build a robotic defender revealed one of
the biggest limitations to the basic littleBits kit that could
impact the driveability of a robot. littleBits allows you to
rapidly prototype like a pro, but the circuits from the basic
kit are kind of like a domino show (the technical term for a
line of dominoes you knock over — the more you know).
They only go in one direction. That’s not to say that you
can’t do wonderful elaborate things with them, however.
Just like expert domino topplers, you can create
sophisticated branching circuits that can create quite the
spectacle, but that could pose an issue for aspiring
roboticists. The littleBits kit does include servos and motors,
but if your creation can only move forward then it doesn’t
seem quite like a true robot. Fortunately, the robot-friendly
Arduino module provides an ideal solution. Before we dove
into programming, we wanted to get better acquainted
with our sources of locomotion.
It's Beginning to Look a
Lot Like Robots
In our starter kit, we had a DC motor module and a
gaggle of servo modules. The DC motor module is nice and
compact, with the signature littleBits magnetic connectors
which were colored green to denote an output module.
The shaft had a flat edge to facilitate connection to THE MOTOR THAT'LL BRING THE ROBOT TO TOWN.