Rhyme of the Modern Submariner
great way to tackle the
challenges of the MATE
Competition. The event
demands that teams complete
three underwater missions that
are part of a scenario inspired
by mid-oceanic ridge research.
The first mission was to free an
OBS trapped mercilessly on the
ocean floor. An OBS is an
Ocean Bottom Seismometer,
and in the game scenario, it
was placed in order to gather
information on ocean floor
seismic events like underwater
eruptions and earthquakes. The good
news is that the OBS did indeed
gather the hoped for information, but
the bad news is that the OBS became
trapped in a fierce lava flow in the
process. Our first mission — should we
choose to accept it — would be to
free the OBS from the lava flow.
It’s basically like an episode of the
Thunderbirds, but instead of sending
puppets to save the day, we’ll be
sending in our ROV.
After freeing the helpless OBS
from the ocean floor, the second
mission was to collect three samples
of the lava flow for analysis. The final
mission was to take a temperature
reading from a hydrothermal vent.
For the competition, the OBS is
represented by a PVC box skeleton;
the lava is represented by eight, two
pound soft dive weights; and the
hydrothermal vent is another PVC
structure spewing hot water. The missions will be discussed in more detail
later, because first and foremost we
wanted to have a working platform.
The ROV-in-a-box would give us a
functional ROV that could be expanded
upon to complete the missions. We
wanted to finish our basic ROV before
worrying about the details of the
missions, and with that in mind, we
popped open the instruction manual
to the first step.
TAU BATES AT WORK.
ROV is primarily made up of speaker
wires, and their 50 foot length was the
perfect size for the MATE Competition.
The ROV kit comes with three motors
from Mayfair Marine: two for the right
and left thrusters, and one for the lift
thruster. The motors come with easy
to install couplers for small plastic
propellers. A soldering iron and the
associated paraphernalia is one of
those things not included in the kit,
but once again these are essentials
for every robot project that roboticists
should have in their arsenal.
After preparing the motors, the
next step is to prepare the CCD camera
and LED cluster used for lighting. The
unforgiving work environment faced
by the ROV requires some extra
The Life Aquatic Meets
the Life Robotic
Now that we had a team of
mechanical engineers, structural
engineers, computer science
engineers, and many more, it was
time to pop open the ROV.
When we first opened it, we were
reminded of our experiences at the
beginning of every FIRST build season
— we were faced with a somewhat
intimidating box of loose parts.
Motors, wire, PVC, and switches
abounded, and the project might have
seemed a bit overwhelming had it not
been for the handy instruction manual.
The ROV-In-A-Box K it comes with a
comprehensive manual that gives easy
to read, step-by-step instructions that
are illustrated by clear pictures.
The first thing that the manual
walks you through is the construction
of the frame for the ROV. The PVC
bits are all nicely cut and ready to go,
but the kit does not include PVC
cement or primer. That’s nothing a
preemptive trip to the hardware store
won’t fix, and the beginning of each
step in the manual conveniently lists
any additional parts required for the
step not already included in the kit.
Thankfully, this list is usually very
short, and most of the entries
are simple tools that any
self-respecting tinkerer should
have at the ready.
The PVC frame goes
together very easily, and it’s a
nice thing to do first because
it already gives you a sense of
the scale of the ROV. The bot
was a bit smaller than we had
initially guessed, but there’s
nothing wrong with that —
just ask the Thunderbirds.
The next step involves the
initial wiring of the motors to
the tether. The tether for the
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