In the September 2017 issue of SERVO, Carol Lynn Hazlett demonstrated the Scribbler’s ability to make very precise movements. While such precision is impressive for drawing (letting the robot live up to its namesake), it’s generally not necessary for autonomous sensor-driven behaviors. In fact, it’s easy to assume that a robot known for its ability to draw might not be worthy of conventional robotic projects. As you will see, such predispositions are unfounded. The truth is that the Scribbler 3 (S3) is an inexpensive fully-assembled robot with many capabilities that are worthy
of your consideration.
The purpose of this article is to spotlight those
capabilities and demonstrate how easily they can be
implemented using a version of the BlocklyProp language
developed specifically for the Scribbler.
The Scribbler has many sensors, but those used in
this article are two infrared units to detect objects in
front of the robot and two reflective sensors for
following a line.
These alone are enough for some interesting
projects, but the S3 BlocklyProp language has built-in
support for servomotors and PING))) ultrasonic sensors
connected to the hacker port (which provides six digital
I/O lines and two A/D pins).
For this article, a small servomotor will act as a
Many people know that Parallax’s Scribbler 3 robot can draw pictures
with precise movements because of its wheel encoders. However, the
Scribbler’s IR and line sensors along with access to a hacker port provide
capabilities that make it a contender for more mainstream robotic
projects. That algorithm will be explained in detail, so you can make
other robots perform these tasks even if you don’t own a Scribbler.
while Following a
Line with the
36 SERVO 02.2018
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By John Blankenship