IEEE Robotics & Automation Magazine - June 2011 - 98

Military Inspection
USVs have been developed for mine sweeping, maritime
security, and evaluating battlefield characteristics, such as
tides and currents in littoral regions. According to the
ONR, the use of unmanned vehicles for mine sweeping
reduces the time necessary to safely sweep minefields, as
has already been shown in Operation Iraqi Freedom [3].
Unmanned vehicles can also remove personnel from the
risk involved in surveillance and reconnaissance. The evaluation of battlefield conditions appears to be a secondary
mission to general environmental monitoring, which is
described in the next subsection.
Three USV systems have been documented for minesweeping missions; these missions require that the vehicle
be able to locate mines in littoral regions under low visibility conditions. Massachusetts Institute of Technology's
(MIT) SCOUT [4] and Oceanographic Systems Laboratory's
REMUS [5] are man-portable vehicles. The ONR is also currently in the process of
* developing a USV module for the Littoral ComSea-RAI is designed for
bat Ship (LCS) [3]. All
three vehicles use fixed
inspecting littoral
sonar sensors.
Two USV-UAV teams
environments for military,
have been developed for
military surveillance and
environmental, and
reconnaissance. The U.S.
Navy Space and Naval
disaster response
Warfare Systems Command (SPAWAR) has
applications.
developed an autono* mous, full-size jet boat [6].
The SPAWAR USV's larger
size can limit where the platform can patrol in a littoral environment, such as beneath piers and shallower depths accessible with smaller draft boats unlike the platform discussed in
this article. Virginia Tech/Navy postgraduate school (NPGS)
have demonstrated a unmanned ground vehicle (UGV),
UAV, and USV robot reconnaissance team composed of
man-portable robots with a high level of autonomy and target
detection at AUVFest 2007 [7].
The Sea-RAI project differs from these five systems
either in size, sensors, or marsupialism. Sea-RAI is man
portable while the LCS and SPAWAR systems are not.
Unlike SCOUT and REMUS, Sea-RAI has an independent
pan/tilt sonar sensor. None of the five vehicles serve as a
marsupial team.
Environmental Monitoring
Environmental monitoring is advantageous to not only
academia and environmental organizations but also the
military. By affixing sensors that collect bathymetry,
hydrographic, and water quality data, researchers can
monitor an area for longer periods of time with less
money than with manned alternatives. Having data over
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IEEE ROBOTICS & AUTOMATION MAGAZINE

JUNE 2011

longer periods of time can assist researchers in better
understanding the patterns of an ecosystem. Renaud [8]
argues that current environmental data about the world is
critical in allowing the Navy to have assured access to
anywhere in the world. USVs could supplement the current environmental data collected by the Navy in both
peaceful and hostile water for less cost and less risk than a
manned ship.
Seven man-portable USV platforms for environmental
monitoring appear in the literature. The earliest-found use
of a USV for environmental data collection is the Deep
Ocean Logging Platform with Hydrographic Instrumentation and Navigation (DOLPHIN) in 1983 by International
Submarine Engineering Ltd. [4]. The MIT alone has developed four USVs capable of collecting environmental data
under the Sea Grant College Program: ARTEMIS [9],
ACES [10], AutoCat [11], and SCOUT [4]. ARTEMIS and
SCOUT are single rigid hull craft, and the ACES and AutoCat, such as Sea-RAI, are catamaran crafts. Other related
catamaran environmental data-collection USVs include:
hydrographic unmanned survey craft (HUSCy) developed
by SeaRobotics [12] and the AEOS-1 [13] by the University
of South Florida.
Two other larger environmental monitoring platforms exist. They are Florida Institute of Technology's
(FIT) autonomous self-mooring vehicle (ASMV) [14]
and the Navy's littoral environmental nowcasting system
(LENS) coastal monitoring UAV [15]. These technologies are currently experimental and may provide alternatives to using USVs for environmental monitoring with
further research.
Sea-RAI is most similar to SCOUT, HUSCy, and AEOS1. Those platforms are man portable and designed with the
goal of being relatively inexpensive compared with manned
data collection solutions and constructed with off-the-shelf
parts for easy repairs. None of the man-portable vehicles
uses a UAV. LENS uses a UAV, but it is not carried by the
USV and can be viewed as an independent platform working concurrently with a USV, not cooperatively.
Disaster Response
The last area of unmanned littoral inspection is an emerging field: disaster response and recovery. Disaster response
is similar to maritime security in that structures must be
closed surveyed and assessed. It is also similar to environmental monitoring in that fuel leaks and pollution sources
should be identified. The primary characteristics of emergency response applications of unmanned vehicles are that
the vehicles must be man portable or man packable (as
transportation is disrupted), must be self-sufficient for
communications [as cell towers and wireless fidelity
(WiFi) points are likely to be destroyed], and that there
may considered debris floating the water creating a navigation and collision hazard.
The only recorded use of USV for a disaster was the
Institute for Safety Security Rescue Technology's response

Table of Contents for the Digital Edition of IEEE Robotics & Automation Magazine - June 2011