enough for TV. We knew that the only way to convince
BattleBots that the design was safe and cool enough for TV
was to build it.
So, we kept working on our PVC prototypes that
appeared in these pages under the guise of a punkin
chunker. Even when BattleBots didn’t return in 2017, we
persisted, confident that another season would happen soon
and that we could still possibly bring a tethered version to
RoboGames (or Robot Wars — though they declined the
tethered version of Capital Punishment for Series 10 over
safety concerns). We built the steel cannon and began
the drive train
that would cart
would have it, in 2018, BattleBots returned. We had a steel
cannon and we had a drive train, but there was much more
to be done. Our design — still called Capital Punishment
at this point — was accepted in February 2018. We had
only a few short weeks to finish the robot. It would be like
litigating a case that landed on a rocket docket.
Motion for Leave to Amend the
By the time we were accepted into BattleBots, we
still had some major problems to solve. Our two biggest
concerns related to firing the cannon. At the time we were
accepted, we had tested the steel cannon, but only by
manual firing (involving a monkey wrench and a long rope).
We had not yet been able to pull off remote firing.
Since we wanted the single strongest shot possible,
we planned to use up all our stored nitrogen in one go, so
there would be no need to close the valve. We envisioned a
valve actuation mechanism to open the valve (once), and a
trigger mechanism that would activate the valve actuation
mechanism. This was all brand new territory, like litigating a
recently enacted statute for the very first time.
There are plenty of wonderful resources out there
for robot builders that provide calculators for vertical disk
design, pneumatic flipper design, four-bar lifter design, and
many more. However, there is no online calculator, no guide,
and no whiff of precedent for a giant nitrogen cannon.
There are no suggestions on how to actuate the valve, or
even what valve to use.
So, we blazed a trail that we thought would work and
that we could execute in the very short build window. Are
there other ways to build a cannon? Definitely! Are there
better ways to build a cannon? We’re sure there are, and
we’re exploring plenty of ideas for next season. Our chief
goal was getting a cannon to BattleBots that worked. Could
a couple of lawyers and a grease monkey pull it off?
Our toughest problem was figuring out the valve
BRUCE SPRINGSTEEL, TWO-LAYER VERSION.
AN EARLY VALVE
TRIAL AND ERROR.
70 SERVO 09/10.2018
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