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THE SCRIBBLER FROM PARALLAX.
Spring is in the air, and all of the pent-up energy from a slumbery winter is ready to be released in a flurry of
competitive sporting action. Two of our favorite
sporting events are on the horizon: the Kentucky Derby in
May, and the Summer Olympics in July and August. The
Olympics are exciting — in part — because competitors
come from all over the world, from a multitude of cultural
and personal backgrounds, to compete in a series of events
universally agreed upon to test skill and determination in
various aspects of the human condition.
Robotics competitions are similarly thrilling but instead
of a clash of physical prowess, designers pit ideas against
one another. The spring and summer bring with them a
host of robotics competitions, like the cosmopolitan
RoboGames and the frenzied FIRST Robotics Competition.
One design aspect of many robots that can mean the
difference between a competitive edge and the status of
also-ran is sensor selection. We’ve been lucky enough to
work on such a broad range of kits that we’ve seen a
plethora of sensors implemented in myriad ways, and we
thought putting together a little Sensor Olympics would be
a fun way to go beyond the datasheets and see how some
sensors compared on a practical level.
The Thin Black Line
EXCAVATING THE LINE FOLLOWING SENSORS.
The first class of sensors we wanted to compare was
comprised of sensors used for line following. Line following
is as classic a robotics event as track and field races at the
Summer Olympics, and as time honored a tradition as
sipping mint juleps at Churchill Downs every May. A perfect
blend of skill and speed, line following contests reward
speedy drive trains as much as they do clever programming.
The timelessness of the event has led to many solutions to
the basic problem of tracking a line, and throughout our
years we’ve gotten a general sense of some of the
common problems faced by line followers. A devious plan
involving a disappearing track and a light box began to take
shape, but first we had to assemble a slate of diverse
Everyday I’m Scribblin’
Our first contender is the artistic ambassador from
Parallax: the classic Scribbler robot. While the Scribbler
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