manned ‘submarines’ to have dived
to the deepest part of the oceans over
50 years apart: the Trieste
Bathyscaphe and Cameron’s DeepSea
After his deep sea trip, Cameron
generously donated the sub to the
Woods Hole Oceanographic Institution
in Massachusetts. Go to
www.deepseachallenge.com/the-sub for more information.
Woods Hole ROV
Nereus Lost in the
Sea Off New Zealand
The sea has long been referred to
as a cruel mistress — both for those
above the waves and those below.
This past May, the scientific
community lost an $8 million state-of-imploded at depth for reasons
The six year old Nereus shown in
Figure 14 was built by Woods Hole
Oceanographic Institution and was in
use at the time of the accident by
researchers aboard the scientific
research vessel, the Thomas G while
exploring the Kermadec Trench at
10,000 meters deep off New Zealand.
The Nereus was considered a
hybrid ROV as it could be human-controlled or be used in an
autonomous mode. With its Kraft
TeleRobotics seven-function hydraulic
manipulator arm (shown in Figure 15)
with a 100 pound capacity, the 6,160
pound ROV could dive to 10,000
meters (except this last time).
Nereus could travel at 3 knots
with its 15 k Wh Li-ion battery pack,
and used up to five of its thrusters in
the ROV mode, or three in the AUV
mode. Just as with the DeepSea
Challenger, the AUV used high
intensity but low power drain LED
light banks. Its sensors consisted of a
magnetometer, plus water
conductivity, temperature, and depth
sensors. Its key sensor was the
scanning sonar with forward looking
and profiling, operating at 675 kHz.
Figure 16 shows the control
room for Nereus during a 6,000 meter
Figure 16. Nereus control center during dive operations. Photo by Ken Kostel.
80 SERVO 08.2014
Figure 14. Woods Hole's Nereus AUV underwater.
Figure 15. WHOI Research Engineer Matt Heintz
demonstrates the manipulator arm.