Telescoping bore gauges look like a little bulb on a
handle with spring-loaded arms. You can use the handle to
get the gauge into hard-to-reach places, release the arms,
and lock them in place; then measure the span of the arms
to get your tricky dimension. We cut the spaces accordingly,
used collars to hold everything in place, and then we were
ready for the chains.
Sizing the chains can be a greasy mess, but with
several sets of hands and a good chain breaker we made
quick work of it. With the chains in place, we could finalize
the placement of the motors. We mounted the motors to a
front plate that attached to the inner frame rail, and the
back of the motors were on mounts attached to the floor.
To place the back motor mounts, we used transfer screws
which are an awesome addition to any roboticist’s toolbox.
Transfer screws are like screws on one side and a punch on
We put them into the back motor mounts, positioned
them where we needed them, and gave them a good hit
with the hammer. Perfectly placed holes, no CAD required.
We removed the chains to gets the motors mounted
and then put them back on. The drive train was ready for
wiring. We used the same Castle connectors on the big
battery as we did for the pack on Troublemaker, and used
some high amp distribution posts to get everything
powered and grounded. We used the same type of AR610
receiver we used in Troublemaker, and programmed the
radio for two-stick tank drive.
We fired up the drive train for the first time with it
elevated on wood blocks on top of our bench, with Brad
Delp wailing in the background about a higher power.
Blinking lights on the receiver and Victor BBs gave us hope,
and the motors roared to life with a press of the joystick.
We brought the drive train out of the garage and put
the cannon on top for a full test. The large bot was
delightfully maneuverable and bracingly loud, and with the
six-wheel drive had no problem hauling around the heavy
Nothing beats the thrill of getting a robot working for
the first time, and we have to say that a large scale project
carries its own special sort of awesomeness. It must be
something about the sheer loudness of it, the volume of
work that goes into it, and the ever present risk that your
creation could grievously injure you.
The great part is we were able to do it all with
hacksaws, transfer screws, and a drill press. Feel free to get
inspired by all of the awesome renders and CNC videos you
see on the forums, but don’t be discouraged if you’re like
us and lack a Solid Works license and a Tormach.
Classic techniques are classic for a reason, and they
even work to get a heavyweight driving. If you can’t get it
working, nothing else matters. SV
SERVO 08.2017 59
IT DRIVES LIKE A REAL HEAVYWEIGHT!
WIRED UP AND READY TO DRIVE!
CHAINED UP AND READY TO WIRE.