Field Trials of the Nereus Hybrid Underwater Robotic Vehicle in the Challenger Deep of the Mariana Trench
Abstract—
This paper reports the results of sea trials of the
Nereus hybrid underwater robotic vehicle (HROV) conducted in
May and June 2009 in the Challenger Deep of the Mariana
Trench, where the vehicle successfully performed scientific observation
and sampling operations at hadal depths of 10,903 m.
The Nereus underwater vehicle is designed to perform scientific
survey and sampling to the full depth of the ocean — significantly
deeper than the depth capability of all other presentday
operational vehicles. For comparison, the second deepest
underwater vehicle currently operational worldwide can dive to
7,000 m maximum depth. Nereus operates in two different modes.
For broad-area survey, the vehicle can operate untethered as an
autonomous underwater vehicle (AUV) capable of exploring and
mapping the sea floor with sonars and cameras. Nereus can be
converted at sea to become a remotely operated vehicle (ROV) to
enable close-up imaging and sampling. The ROV configuration
incorporates a lightweight fiber-optic tether for high-bandwidth,
real-time video and data telemetry to the surface enabling highquality
teleoperation. A manipulator, lightweight hydraulic power
unit, and sampling instruments are added to provide sampling
capabilities. This paper reports a brief overview of the Nereus
vehicle design, and reviews the initial results of the eight dives
conducted on this expedition, including two dives to more than
10,900 m depth. The Nereus vehicle is designed to render all parts
of the Earth’s seafloor reachable and the sea trials of its fullocean
depth capability in May and June 2009 were successful.
I. INTRODUCTION
On May 31, 2009 the Nereus hybrid remotely operated
vehicle (HROV) successfully completed its first dive to the
hadal ocean depth of 10,903 m at 11◦22.1’N, 142◦35.4’E in
the Mariana Trench in the Western Pacific. This 26-hour dive
was comprised of an 8.5 hour descent to 10,903 m, a 10.75
hour bottom interval during which the vehicle provided live
video via its fiber-tether multi-gigabit optical telemetry and
performed geological and biological observation and sampling,
1Department of Applied Ocean Physics and Engineering and Department
of Biology (Bors and Shank), Woods Hole Oceanographic Institution, Woods
Hole, MA
2Department of Mechanical Engineering, The Johns Hopkins University,
Baltimore, MD
3U.S. Navy Space and Naval Warfare Systems Center Pacific
4School of Ocean and Earth Science and Technology, University of Hawaii
and a 6.5 hour autonomous ascent to the surface. This paper
gives a brief overview of the Nereus vehicle design, and reports
results of Nereus sea trials conducted in May and June 2009
culminating in the Challenger Deep of the Mariana Trench
(Figure 1) in the Western Pacific Ocean near the island of
Guam [12].
The goal of the Nereus project is to provide the U.S.
oceanographic community with the first capable and costeffective
vehicle for routine scientific survey, sea floor and
water-column experimentation, and sampling to the full depth
of the ocean of 11,000 m—significantly deeper than the depth
capability of all other present-day operational vehicles. For
comparison, the second deepest underwater vehicle currently
operational worldwide can dive to 7,000 m maximum depth
[17]. Nereus operates in two different modes. For broad area
survey, the vehicle can operate untethered as an autonomous
underwater vehicle (AUV) capable of surveying and mapping
the sea floor with sonars and cameras (Figure 2, right). For
close-up imaging and sampling, Nereus can be converted at
sea to become a tethered, remotely operated vehicle (ROV)
(Figure 2, left). The ROV configuration incorporates a novel,
lightweight, fiber-optic tether (Figure 3) for high-bandwidth,
real-time video and data telemetry to the surface, enabling
high-quality, remote-controlled teleoperation by a human pilot.
Nereus’s first sea trials were conducted in November 2007
from the R/V Kilo Moana in the Pacific Ocean near Oahu,
Hawaii. The 2007 sea trials demonstrated vehicle operations in
AUV mode and ROV mode to a depth of 2,270 m, as reported
in


Download full report
http://dtic.mil/cgi-bin/GetTRDoc?Locatio...=ADA527831