The axe linkage is unique.
chassis cut, reinforced, and rebuilt,
and the damaged internals repaired
or replaced. It was getting expensive,
time consuming, and frustrating.
More importantly, however, the
space frame chassis was so patched
and welded that it was cracking in
almost every fight. It was time to
build either a completely new chassis
for Edgehog, or build a successor.
In the good old days, axes could
pierce armor. By utilizing a sharp,
lightweight axe head, a large
pneumatic ram and an acceleration
linkage, holes could be punched in the
steel, aluminum, or thin polycarbonate
skin of the opponent quite regularly.
More recently, the robots have been
armored in thick titanium, heavy
Scars of a difficult season.
steel wear-plate, and thick
polycarbonate. To break through
such material and get to the internal
components was almost impossible.
The solution chosen for our
new robot “Crossfire” was a heavy,
blunt trauma weapon; an 11 kg
bludgeon that would damage the
enemy, bend the armor supports,
and twist the chassis. This medieval
looking appendage was to be swung
through a unique, innovative linkage
from the 100 mm pneumatic ram.
The linkage acts like a gearbox,
taking advantage of the huge linear
forces available from the ram (which
runs at only 200 psi, but is capable
and tested to 1,000 psi should the
motivation ever arise) by way of an
unequal length swing arm and
custom-made spur gear. The result is
that the 11 kg bludgeon swings at
one and a half times the speed of
the ram, through 180 degrees of
motion, lifting the whole machine
into the air, and hitting with enough
energy to bend half inch steel plate.
It also has more than enough force
to right the whole robot should it
be turned over during battle.
The twin pressure bottles and large ram sit
under the robot.
From the lessons learned with
its predecessor, Crossfire had to be
tough. So tough in fact, that it has
never been externally damaged
since entering its first combat event
in 2009. The outer skin is made of a
specially selected high carbon
content steel wear-plate, shaped
and welded in such a way as to
deflect, resist, and survive any
current weapon in the UK.
Testing the weapon.
The hard outer shell is mounted
to the curved internal spine with
heavy-duty brackets and bolts, welded
reinforcing beams, and struts. All
internal components are shockproof,
and flexibly mounted where possible.
The result is a rock solid machine
that has yet to be scratched.
Having spent several years
updating, upgrading, repairing,
modifying, and (in some cases)
destroying our motors, speed
controllers, and batteries, we have a
clear understanding of what works
and what is reliable in UK-based
combat. Unfortunately for us (and
our national pride), what we have
found over these many years of testing
is ... buy American! The motors and
gearboxes are manufactured in the
USA for heavy-duty electric
wheelchairs. Controlling these 24
volt gear-motors is a single Robot
Power Sidewinder; with a pair of
used 36 volt NiCad Battle-packs
Edgehog was badly
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