Robytes
by Jeff and Jenn Eckert
ROVs Aid BP
The Maxximum ROV from Oceaneering International.
It has been widely reported that robotic submarines
were deployed within hours of the BP oil disaster, but
details were sketchy. Were they Navy subs? Specially
modified UAVs? Well, it turns out that Oceaneering
International, Inc. ( www.oceaneering.com), has been
offering a variety of products and services geared toward
offshore oil exploration and production for years. Included
is a line of remotely operated vehicles, eight of which were
attempting to awaken the well’s blowout valve as of this
writing. And we’re not talking about dainty little tadpoles.
Oceaneering’s Maxximum® model is a dual-manipulator, 300 HP slogger
that — with its enhanced
thruster configuration — offers
nearly a ton and a half of
center lift capacity and
forward pivoted bollard lift
greater than 1,800 lb. It also
sports microprocessor-based
telemetry and a direct fiber
optic link to the console,
providing a transmission path
for video (eight channels) and
data signals. The standard
unit is rated for depths of
10,000 ft. Weighing in at
10,750 lb in air, it can carry a
payload of up to 1,100 lb. For
more indepth coverage on the
ROVs used in this effort, check
out the article on page 55 of
this issue.
motion in an absolute sense, as it actually does suck a
little energy out of the environment. But the Sounding
Oceanographic Lagrangrian Observer Thermal RECharging
(SOLO-TREC) autonomous underwater vehicle uses a
clever thermal recharging engine that draws its energy
from temperature differences found at different ocean
depths.
In a joint effort by NASA’s Jet Propulsion Lab
( jpl.nasa.gov) and the Scripps Institution of
Oceanography ( scripps.ucsd.edu), the UAV has already
completed more than 300 dives to depths of up to 500 m
(1,640 ft). The secret is a set of 10 external tubes that are
filled with a waxy phase-change material that alternately
expands and melts in warm water, and solidifies and shrinks
in cold. This puts pressure on an oil reservoir that drives a
hydraulic motor, and the motor produces juice to recharge
the sub’s batteries. You get about 1.7 watt-hours ( 6,100
joules) per dive which is enough to run the vehicle’s
instruments, communications equipment, a GPS unit, and
the buoyancy-control pump. No, it doesn’t produce
enough to provide horizontal propulsion, but what do you
want for nothing? As you read this, SOLO-TREC has been
redeployed on an extended mission that is planned to last
months, if not years.
The SOLO-TREC AUV powered by temperature differentials.
UAV Achieves Perpetual
Motion (Almost)
Okay, it’s not perpetual
8 SERVO 07.2010