team for the FIRST Tech Challenge. I immeditaly
registered, and my FIRST 2007-08 season began!
When my Vex kit finally came in the mail, it
was building time, right away, without hesitation.
I already had many designs in my head for this
year’s game entitled Quad Quandary, in which
alliances of two robots each must score points with
rings and hexagonal goals around the field. My
first design was a three wheeled ‘scooter’ robot
which could grab rings and easily score them on
the high goal. Well, with limited parts, this
proved difficult. Eventually, wanting to follow the
K.I.S.S. principle (Keep It Simple, Stupid), I tried a
Another five designs, all with a powerful
drivetrain, but they each were ruined by my huge,
complex arms. With only so many parts, it was
hard to build an arm, let alone be able to pick up
plastic rings with just the small grip of metal
attached to the servo motors. So, after much
thought and now designing with the consideration of the
amount of parts I have, I went to Plan B. No arm. How
can I score points with no arm!? Well luckily, the Game
Design Committee gave teams like mine the luxury of a
side goal. This side goal is flat on the ground with one
point given per ring score.
There was also the option to push the hexagonal
goals into your sectors for another seven points, which
luckily scored a lot in the actual game. Another advantage
to my new design would be torque! I planned to have
enough torque to be able to push whatever robot or
obstacle stood in my path. Also, I wanted to be able to
push those goals (which turned out to be simple!). This
last strategy took a few design iterations. The first was
another attempt at a high torque ‘scooter’ ‘bot that
had omni-directional capability. My original attempt
at this failed and so did my second one which actually
came very close to success, but when it came to
programming autonomous mode (key part to the
game!), it didn’t make the cut.
My last gloriful design was relatively simple and yet
extremely powerful. It was a simple 6WD robot with a
plow and sensors scattered over it. The 6WD gave it so
much torque it could even push the two-time champion
robot built by Simbotics (see Figure 1). The plow was
really effective at getting rings and hexagon goals into
their locations quickly and not stopping because some
robot tried to get me!
Before I talk about the competition and what
happened on that amazing day, I want to go more
in-depth about actually building the robot with the Vex
Robotics platform ( www.vexlabs.com). Building with Vex
allows you to be creative, and build robust and powerful
‘bots without using all those expensive shop tools like
band saws and power sanders. The only tools I used
with building Vex were two Allen keys (or hex keys, hex
wrenches, whatever you like to call them) and a small
wrench. All of which came with the kit.
FIGURE 2. Between matches, all the teams have to fix their
robots from the brutality of competition. In this photo,
Team 468 is fixing their robot.
FIGURE 3. My robot going in to push a goal into my
alliance section for seven points.
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