SERVO 11.2016 23
once it started spinning
As with all the prior
upgrades, the next
weak spot made an
appearance. This time, it
made its way back to
the weapon shaft.
While it was reasonably
well supported and a
decently tough material,
eventually a big hit or
several would either
bend the shaft, explode
the 3 mm bearing, or
cause the shaft to work
its way out of position.
This lead to the
final design revision: an
overhaul of the motor-in-weapon setup after
Algos managed a 20-5
record in the V2
The two things that
had to happen to the
weapon were that the shaft had to be
actively retained and it had to be
strong enough to resist bending even
after the nastiest hits. After looking at
a few options, I settled on removing
the bearings from the stator (the part
of the brushless motor with the
copper windings) and drilling it out to
accommodate a 1/4” shoulder bolt.
This also meant that I’d have to move
the bearings into the drumette itself.
After finding suitable bearings
and taking measurments to determine
the correct offset between the new
bearings and the old stator, I got all
the critical parts ordered including a
small pile of steel shims that would
allow me to precisely set the spacing
and had a fresh drumette machined.
For this arrangement, the stator
was mostly left as delivered outside of
the removal of the bearings and the
enlarged bore. For the rotor, however,
the only part left was the magnets
and the metal ring that retains them.
This was pressed and glued into the
drumette, effectively turning the
drumette into the new rotor.
At this point, Algos was in its final
state. The drive was fast, the weapon
was durable and destructive, and the
chassis could handle just about
anything thrown at it.
The final revision of Algos lived up
to its potential, winning Motorama
2015, the Freeside Robot Street Fight,
Clash of the Bots 2015, and Dragon
Con Robot Micro Battles 2015 — all
with essentially no maintenance, no
issues, and a total of two losses.
By this point, the first drumette
was looking a bit worn out, so Algos
was taken apart for a cleaning and
During the cleaning, it was clear
just how hard the current setup is on
the stator. However, it also was clear
that even with the stator feeling some
of the shock, the weapon as a whole
was holding together well. With a
fresh disk on and Algos reassembled,
it was ready for its final run.
Algos went undefeated at Robot
Battles 57, Robot Battles 58, and
Motorama 2016, having a combined
13-0 run across those competitions.
With the win at Robot Battles 58, it
had also managed to win every event
it attended for a full year, and finished
with seven straight event wins and an
overall record of 32-2.
While Algos could fight again as it
sits or be fixed up a bit and look as
good as new, it’s done everything I
wanted it to do and I’ve learned a lot
in the process.
It’s had an amazing run, and
there’s nothing I want to change on
it. I think that means it’s time for
something new. SV
Here’s the magnet ring and drumette
prior to being pressed and bonded
together along with the shoulder bolt
used as the weapon shaft. Algos V2.5 freshly assembled and ready for Motorama 2015.
The setup’s a bit rough on the stator,
but it’s still running strong.