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This Month:
28 BUILD REPORT:
The Quest for a Different
Kind of Flipper: Improving
the Trigger
by Zac O’Donnell
31 Then and Now —
A Decade Later With
Brian Nave
by Kevin M. Berry
34 EVENT REPORT:
FIRST Orlando Regionals:
A New Set of Heroes
Emerges
by Collin Berry
37 CARTOON
38 Tips from the Pits:
Speeding up a Motor
Change
by Pete Smith
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_CombatZone
28 SERVO 06.2013
BUILD REPORT:
The Quest for a Different Kind of
Flipper: Improving the Trigger
● by Zac O’Donnell
In last month’s issue of SERVO, I wrote about my first two
attempts to build a flywheel-powered flipping robot; the latter
of which competed under the
name Reclipso.
This time, I will talk about
some of the difficulties I faced
with those two attempts and
how the next design addressed
some of them. I will also recount
my experiences while testing,
and the steps I took to mitigate
the issues that came up.
The first and most limiting
drawback of Reclipso was its
inability to drive while the
flywheel was spinning. This was
caused by an oversight when I
selected the weapon controller.
The controller I purchased
only supported automatically
detected cutoff voltages for
lithium polymer batteries. This
caused a problem because I was
using the small 1,100 mAh A123
cells which are a lower voltage
than lithium polymer batteries.
This caused the weapon
controller to go into safety cutoff
mode as soon as the battery
voltage dropped from the
current draw of the drive motors.
Reclipso also could only fire
the weapon a single time before
the trigger mechanism jammed.
While I always intended for the
system to be able to disengage
and fire several times, a lack of
testing time resulted in a one hit
wonder.
This behavior was only a
slight improvement over the
original prototype trigger
mechanism which could not
even engage the weapon reliably
a single time.
Reclipso used a steel hook to
grab the flywheel and pull the
arm through its stroke, but the
problem was that the steel hook
did not unhook from the flywheel
once the arm reset.
Now that I had two failed
attempts under my belt, I decided
to soften my lofty goals of
