is required is that the outer ring is
stopped from rotating.
Now that you have the gearbox
locked in “high” and have disabled
the torque mechanism, you can refit
the motor to the gearbox. Do not
be tempted to run the motor yet.
It is necessary to add something
that will lock the gearbox to the
motor. Failure to do so will result in
gears flying in all directions (guess
how I know this!). In the original
drill, the case performs this function
and tabs on the gearbox fit into
slots in the case. A couple of
minute’s work with a hacksaw cut
the relevant sections out of the case
(Figure 11). These can be secured
in position with a simple tie wrap.
The complete motor and gearbox can be seen in Figure 12 next
to one of the smaller originals. It
weighs 1.4 lbs (0.4 lbs heavier) and
the assembly is considerably longer
so that needs to be taken into
account in your design. The 3D solid
models can be found in the “Solid
Models” section of my website at
www.teamrollingthunder.com.
You can get hubs for the popular
Colson wheels that fit directly onto
the shafts from www.kitbots.com
and these are secured by the left-hand threaded screw. Figure 13
shows how the new motors will fit
into the existing CheepShot 3.0
chassis. SV
Photographs by Peter Smith.
MANUFACTURING:
Modular Design in
Combat R botics
● by Blake Hooper
In combat robotics, modular design can be a safe approach
to dealing with both damage and
changing circumstances in the
arena. The basic principle works by
separating the main components of
your combat bot into multiple,
independent assemblies. Once all of
these modules are completed, you
can assemble the entire bot quickly
and swap out the modules easily for
repair or replacement by a better
component. In situations where
your motor burns out or your
weapon assembly is destroyed,
having a back-up module will end
up extending your bot’s life. Like
any type of design, however, there
are advantages and disadvantages
to using this method.
flexible strategy during matches.
Depending on your opponent, your
weapon type might not be good
enough necessitating a change, or
you might need to completely rearrange where the armor is focused.
Finally, one of the minor advantages
is the ability to build in stages.
Instead of working from scratch,
you can construct one assembly at a
time, finishing different aspects of
your bot independently. Many
builders will leave projects unfinished, citing one incomplete part or
another as the reason for not finishing
their bot. Using a modular design,
they could still enter competition,
filling in the unfinished component
What’s Good and
Not So Good
To begin with, there is a great
advantage in design flexibility.
Immediately, you will be able to
broaden your design options from
the weapon type to armor placement. This also means having a
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