Unmanned marine systems are categorized into
two categories, one category is unmanned surface vehicles (USVs), and the other
is unmanned underwater vehicles (UUVs). When analyzing the method of data
depiction and presentation between the two, it is vastly different. For
underwater systems high bandwidth communication is often difficult, therefore
missions are usually preprogrammed and the systems often operate with an
increased level of autonomy. This makes the mission control aspect of these
systems relatively simple. For systems such as the Bluefin 21, the control
station and data processing system is a Windows based laptop loaded with the
company’s proprietary software (Bluefin Inc., 2015). For surface based systems
such as the Protector USV the mission control of the system is more similar to
an unmanned aerial system. When operating on the surface, weather, sea
conditions, ship traffic, and precision targeting are required in real time.
Having to remotely interpret the USV’s immediate environment requires complex
depiction and presentation strategies. Studying current systems used in data
depiction and presentation as well as being able to identify their shortfalls
will help engineers in the future develop new methods and techniques in the
realm of data depiction and presentations for unmanned systems in general.
Data Depiction and Presentation for the Protector
The Protector USV is an advanced surface
warfare platform that can be utilized for anti-terror/ force protection
missions, port security, and intelligence surveillance and reconnaissance. The
system consists of a 30ft inflatable rigid hull boat, an interchangeable
mission payload, and a two person command and control station that can be
either placed on a larger ship or on shore (Rafael LTD., 2010). In terms of
data depiction and presentation, the command and control station is broken down
into two separate functions. There is a vessel control station and a payload
control station. The mission payload for this system is very similar to UASs,
therefore, for the purpose of this study, understanding and studying the vessel
control station is paramount to the payload control. Controlling a surface
vessel is very difficult when there is no proprioceptive feedback being given
to the operator. In order to compensate for the lack of proprioceptive feedback,
the Protector has been designed with a higher degree of autonomy than most
other unmanned systems. The system features cameras, sensors, and algorithms
that pick optimal sea paths and account for weather, waves, and currents. The
system also has a dynamic stabilization capability as well as autonomous sense
and avoid capability. All these systems are overlaid and presented to the
vessel operator in a control station that is a replica of the ships actual
controls. There is not only a replica of the vessel’s control, but there is
also a display of an overhead map as well as a view from the safety camera
which is located similarly to wear the skipper would actually be sitting or
standing if they were on the vessel (IWeapons.com, 2007). The operator can either control the system in
a manual or semi-autonomous mode. During docking and precision maneuvers,
manual control is ideal. At high speeds in the open ocean, the semi-autonomous
method of control is better suited for the mission.
Data Depiction and Perception Challenges
One of the largest challenges for any
surfaced based marine system is the lack of situational awareness and proprioceptive
feedback. Compared to a manned surface vessel, the unmanned skipper receives
all feedback in the form of quantifiable numbers and sensor readings rather
than actual feedback like wind being blown through hair, boat movement, and
engine sound. Not being able to feel the waves under the boat, compounded with
poor visibility of the surface conditions during night operations or in dense
fog makes it more challenging to get the most out of the USVs performance. Not
having these physical cues makes piloting an unmanned surface vessels a complex
task, but there are a few methods to mitigate this challenge. One method is turning
to a computer system to add a high degree of automation that will off load some
environmental based decisions from the skipper, such as sea path selections and
stabilization. This helps to a degree during simple maneuvers, but in terms of
precision maneuvers or extreme weather and sea conditions, this solution does
not provide the best outcome (Gilat, 2012). Another tool used to help USV
skippers is training. Similar to pilots training to fly with just flight
instruments, conditioning USV skippers to learn how to effectivly turn
numerical data into a cognitive picture of the remote environment is essential
(Gilat, 2012). In order to aid in this process, I propose to include proprioceptive
feedback in the command and control station via full motion simulations.
Alternative Data Depiction and Presentation Strategies
In aviation, pilots that are training to fly
with only instruments first train on simple computer based simulators. Once the
pilot can gain the ability to cognitively process numerical and instrument data
into spatial awareness, they graduate to a full motion simulator. This helps
them become physically aware of the simulated environment as well as be able to
physically sense the aircrafts performance. The real time motion simulation
helps the pilot manage their control inputs as well as determine aircraft
health and performance. If engineers can create the same full motion feedback
for USV skippers, I feel that it would help bridge the gap from numerical
sensor data to real life spatial and environmental understanding. Not only
simulating the motion of the vessel, but being able to provide simulated wind
speed and direction, as well as engine sound would also help the skipper gain
clear understanding of the environment as well as the USVs performance. The key
to this system would be real time feedback. If there is just a few second delay
between the USVs actual movement and corresponding simulated movement of the
command and control station, the required control inputs to correct for environmental
influence would be too late to be effective. Another difficulty of this system
is the size and complexity of a full motion command and control station. This
system would be better suited for a land based control facility rather than a
ship based facility. If proper training and full motion feedback is designed
into the Protector, an unmanned skipper could manually control the vessel to
perform more complex and precise maneuvers as well as allow for operations in
more severe sea and weather conditions.
Increasing the complexity and simulated feedback
of an USV skipper’s control station is a decision that needs to be made based
on mission limitations and mission profiles. For a steady state harbor protection
mission that requires precise maneuvering around ships, docks, and the
shoreline, the full motion command and control station may increase the
Protectors effectiveness and allow more complex manually controlled missions.
In expeditionary missions, a mobile form factor and highly automated mission control
method may be a more effective solution. Either way, as a study in design,
engineering a full motion command and control station for something like the
Protector USV could also provide valuable insight for land based unmanned
systems or even rover based systems that operator on the surface of Mars. The
most difficult aspect to this type of integration is the need for real time
data connections that could prove difficult over large distances. An emerging
methodology involving laser based communication could be the key to decreasing
data latency between vehicle and control station.
References
Bluefin Inc. (2015).
Operator Software » Bluefin Robotics. Retrieved February 21, 2015, from http://www.bluefinrobotics.com/technology/operator-software/
Gilat, E. (2012,
August 5). The Human Aspect of Unmanned Surface Vehicles. Retrieved February
21, 2015, from http://defense-update.com/20120805_human_aspects_of_usv.html#.VOYIWfnF9AU
Iweapons.com.
(2007, March 29). Protector. Retrieved February 21, 2015, from http://web.archive.org/web/20070329024450/http://www.israeli-weapons.com/weapons/naval/protector/Protector.html
Rafael LTD.
(2010). PROTECTOR: Unmanned Naval Patrol Vehicle. Retrieved February 21, 2015,
from http://www.rafael.co.il/Marketing/288-1037-en/Marketing.aspx
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