Note: Descriptions are shown in the official language in which they were submitted.
CA 02750259 2011-08-23
Our reference: 2010.23DE
30.08.2010
Unmanned underwater vehicle and method for operating an
unmanned underwater vehicle
The invention relates to an unmanned underwater vehicle which can be
controlled according to predefinable control information by means of a control
device. The invention also relates to a method for operating such an unmanned
underwater vehicle.
Unmanned underwater vehicles open up a multiplicity of possibilities for
different
underwater work. In contrast to manned underwater vehicles, unmanned
systems can reach greater working depths and can operate in environments
which are too dangerous for divers or manned systems. Unmanned underwater
vehicles are also able to perform most of the tasks which were previously
carried
out by larger research ships. Unmanned underwater vehicles therefore afford a
large cost advantage over manned systems. Unmanned underwater vehicles can
be roughly subdivided into remotely controlled underwater vehicles (ROV =
Remotely Operated Vehicle) and autonomous underwater vehicles (AUV =
Autonomous Underwater Vehicle). Remotely controlled underwater vehicles
(ROV) are generally remotely controlled via a connection cable, usually by a
human operator who predefines control commands for the underwater vehicle,
for example from a control station of the system platform, for example a
surface
ship.
Autonomous underwater vehicles (AUV) perform their respective mission without
being continuously monitored by human operators but rather follow a predefined
mission programme. Autonomous underwater vehicles comprise their own power
supply and do not require any communication with the human operator during a
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mission. After the mission programme has been carried out, the autonomous
underwater vehicle likewise independently surfaces and is recovered, for
example by a mother ship which has a corresponding recovery device. The
autonomous underwater vehicle is usually provided with suitable sensors, for
example sonar sensors. The measurement results are recorded or are wirelessly
transmitted to the mother ship. An autonomous underwater vehicle is
particularly
suitable for large-scale or large-area reconnaissance under water and
investigates the underwater environment, generally without coming into contact
with detected objects under water.
Remotely controlled underwater vehicles are used, in particular, for missions
with
locally limited, more detailed investigations under real-time conditions, the
underwater vehicle often also having to act on an object, for example for
repair
purposes.
Both long-range reconnaissance or investigation and locally limited work under
real-time conditions are required in a multiplicity of underwater missions,
for
example when inspecting and, if necessary, repairing offshore installations,
for
example pipelines. Vertical walls often need to be examined under water, the
walls having to be examined over a long inspection range according to their
length under water and, if damage is detected, the damage having to be
diagnosed in more detail and repaired, if necessary. Desired fields of use of
unmanned underwater vehicles are also, for example, harbour inspections
including the inspection of channel walls, quay walls, sheet pile walls, in
particular with regard to the undermining of underwater walls. Harbour
inspections can also include the examination and possibly manipulation of
hulls.
Both types of vehicle are conventionally used for tasks of the abovementioned
type. In this case, depending on the specific requirement, either the
autonomous
underwater vehicle or the remotely controlled underwater vehicle is used, or
both
vehicles are used in succession, each with subtasks of a complete mission.
The provision of two types of unmanned underwater vehicle, namely both AUVs
and ROVs, results in an increased outlay on equipment and thus in high costs.
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Apart from the fact that a plurality of fully equipped underwater vehicles
often
have to be kept available, different recovery systems also generally have to
be
provided for the different vehicle types in order to be able to recover both
vehicle
types after a mission has been concluded and to bring them on board a mother
ship, for example. In this case, different recovery systems are usually
conventionally used for autonomous underwater vehicles and remotely controlled
underwater vehicles. The high outlay on equipment for a plurality of
underwater
vehicles and corresponding recovery systems generally results in difficulties
when accommodating the equipment on board a mother ship where little space is
usually available, in particular on deck. Finally, the provision of both AUVs
and
ROVs gives rise to a considerable amount of effort needed to maintain the
unmanned underwater vehicles and also results in a large amount of training
for
the operating personnel of the underwater vehicles and the respective recovery
systems.
The invention is therefore based on the problem of reducing the outlay for
investigations of underwater areas using unmanned underwater vehicles.
According to the invention, this object is achieved with an unmanned
underwater
vehicle having the features of Claim 1. The problem is also solved by a method
for operating an unmanned underwater vehicle having the features of Claim 11.
The invention provides for the unmanned underwater vehicle to be able to be
controlled either in an autonomous operating mode or in a remotely controlled
operating mode, as a result of which the unmanned underwater vehicle
according to the invention can operate both autonomously and in a remotely
controlled manner. As a result, underwater tasks with a need for large-scale
reconnaissance and, at the same time, selective, that is to say locally
limited,
investigations under real-time conditions can be carried out by an individual
unmanned underwater vehicle. The control device controls the operating devices
of the underwater vehicle on the basis of predefined control information. In
this
case, operating devices are understood as meaning both the power supply and
navigation and communication devices and other devices provided for operating
the underwater vehicle. Operating software of the control device uses the
control
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information to determine the suitable measures of the operating devices for
the
intended manoeuvre of the underwater vehicle.
Predetermined internal control information from a memory element are
predefined to the control device of the unmanned underwater vehicle in the
autonomous operating mode, with the result that the mission is carried out by
an
internal controller in the autonomous operating mode without being monitored
by
human operators. In this case, the control information may be predefined to
the
control device as part of permanently programmed operating software or a
specific mission programme. In this case, manoeuvres within a mission
programme may be stored as control information, for example, or the
performance of particular control measures when associated events are present
may be predetermined. As part of "intelligent" control, for example, control
information may be provided for manoeuvres which are associated with
particular
situations which can be detected by sensors of the underwater vehicle, for
example evasion manoeuvres. In this case, the control information also
comprises assessment algorithms for assessing incoming sensor measured
values. During large-area underwater reconnaissance, if objects or damage
is/are found in a structure to be investigated, provision is advantageously
made
for the immediate or else subsequent performance of a manoeuvre during the
mission, which manoeuvre allows the closer inspection of the object.
External control information are predefined to the control device via a
communication device of the underwater vehicle in the remotely controlled
operating mode, with the result that underwater work can be carried out under
real-time conditions in the manner of ROVs which are known per se.
The underwater vehicle advantageously has an operating mode selection means
which can be used to set either the autonomous operating mode or the remotely
controlled operating mode as required. The underwater vehicle can therefore be
operated as an AUV or ROV depending on the need of a mission to be
specifically performed. In this manner, for example when investigating a wall
under water, the underwater vehicle can quickly cover that working area of the
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wall which is to be investigated, for example during an interval, with the
autonomous operating mode. If damage is detected, the underwater vehicle is
changed over to the remotely controlled operating mode. In the remotely
controlled operating mode, an operator can locally investigate the location in
question and can repair it, possibly with the aid of the underwater vehicle.
The operating mode selection means generates a corresponding operating mode
selection signal in order to set the selected operating mode (autonomous
mode/remotely controlled mode) or to change between the operating modes. The
operating mode selection signal is preferably input to the control device,
with the
result that the operating mode selection signal is used to set the control
device to
the future reception of internal or external control commands, the processing
of
the latter and corresponding control of the operating devices of the
underwater
vehicle. Depending on the operating mode selected, the control device controls
the operating device either according to internally predefined control
information
(autonomous mode) or externally predefined control information (remotely
controlled mode) on the basis of its operating software.
In one advantageous embodiment, the mode selection means is arranged on the
underwater vehicle such that it is accessible from the outside and can be
manually operated. Manual operation of the operating mode selection means
makes it possible to set the unmanned underwater vehicle according to the
invention to the operating mode suitable for a mission in a simple manner
before
the start of the respective mission, for example on board the mother ship. In
this
case, the mode selection means may be a switch which is fitted to the outside
of
the hull of the unmanned underwater vehicle and, when operated, passes an
operating mode selection signal into the interior of the underwater vehicle
and
ultimately to the control device.
The operating mode selection means can be advantageously remotely controlled
via a wireless communication medium or via a connection cable, as a result of
which the operating mode can be changed even during the mission, that is to
say
after the underwater vehicle is in the water, if necessary by remote control.
The
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remotely controlled mode can likewise be switched off by operating the
operating
mode selection means, with the result that the underwater vehicle can start or
continue its reconnaissance patrol in the autonomous mode. The changeover of
the operating mode is advantageously wirelessly remotely controlled via radio,
sound or in a similar manner.
The underwater vehicle advantageously has a cable receptacle for connecting
the connection cable which is preferably a fibre optic cable. The cable
receptacle
is advantageously arranged in the region of the stern of the underwater
vehicle,
with the result that the underwater vehicle pulls the connection cable behind
it. In
this manner, the connection cable is kept away from the underwater vehicle and
is protected against damage. The cable receptacle and the connection cable are
preferably in the form of a plug-in connection, with the result that the
connection
cable can be adapted to the underwater vehicle with few actions.
In one preferred refinement of the invention, a common wireless communication
medium or a common connection cable is used to connect the mode selection
means and the communication device for external control information. The
common connection is used both to change over the operating mode in a
remotely controlled manner and for communication between the underwater
vehicle and the system platform, for example the mother ship, in the remotely
controlled mode. A common connection cable can also be used to supply power
to the unmanned underwater vehicle, with the result that, during a mission of
the
unmanned underwater vehicle in the remotely controlled mode, the load on the
underwater vehicle's own energy sources is relieved or said sources are not
needed at all. It is thus possible to initiate a mission as an ROV immediately
and
without the use of batteries if necessary.
In addition, the unmanned underwater vehicle also advantageously
communicates with the mother ship during the autonomous operating mode via
the common wireless communication medium or the common connection cable.
Communication is preferably used for the remotely controlled request to
transmit
information to the system platform. For example, a signal which activates a
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predefinable program for providing information can be supplied to the control
unit
by remote control. In this case, a manoeuvre for controlling a radio buoy or a
transponder or else the release of a radio buoy which is carried along may be
provided in order to forward information to the system platform at a high
transmission rate.
In another advantageous embodiment of the invention, either the autonomous
operating mode or the remotely controlled operating mode is set according to
the
specification of stored operating software of the underwater vehicle and/or a
mission programme stored for a specific mission. For this purpose, a memory
element can advantageously cause an operating mode change signal to be
emitted in accordance with the specification of the operating software. In
this
case, a changeover from the autonomous mode to the remotely controlled mode
may be provided, in particular, for the situation in which the control device
detects, from sensor measured values, the presence of a particular situation
for
which a changeover to the remotely controlled mode is provided. As an
alternative to the operating mode being directly changed over by the operating
software or the mission programme, provision is made for the control device to
indirectly initiate the change of operating mode and to request it from the
system
platform, with the result that an operator directly changes or can change the
operating mode.
In one advantageous embodiment of the invention, the underwater vehicle
comprises a main drive, which acts in its longitudinal direction, and at least
one
manoeuvring drive which acts in a direction that differs from the longitudinal
direction. In this manner, the unmanned underwater vehicle according to the
invention can be accurately positioned by means of control commands from the
human operator in the control station during the remotely controlled operating
mode in order to carry out precise investigations under real-time conditions
or
repairs.
The manoeuvring drive is advantageously provided in the region of the bow of
the underwater vehicle and thus enables improved navigation of the underwater
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vehicle, if appropriate in a manner suitably matched to the main drive. The
lateral
linear drive is advantageously provided as a lateral linear drive on both
sides of
the hull. Alternatively or additionally, lifting drives may be provided as
manoeuvring drives.
The underwater vehicle advantageously has controllable manipulation devices,
preferably robot arms, in order to be able to carry out manipulation tasks,
for
example repairs, in the remotely controlled operating mode, in particular.
In another embodiment, the underwater vehicle has a receiving device for
receiving, transporting and/or storing objects. Such objects may be, for
example,
explosive charges or samples which were collected in the working area and are
brought inside the receiving device with the aid of the manipulation devices.
Further advantageous embodiments emerge from the dependent claims and
from the exemplary embodiments which are explained in more detail below using
the drawing, in which:
Fig. 1 shows a schematic side view of an unmanned underwater vehicle
according to the invention,
Fig. 2 shows a schematic side view of a second exemplary embodiment of
an unmanned underwater vehicle according to the invention, and
Fig. 3 shows a schematic side view of a third exemplary embodiment of an
unmanned underwater vehicle according to the invention.
Fig. 1 shows an unmanned underwater vehicle 1 with a pressure-resistant hull
2.
Different operating devices of the underwater vehicle 1 are arranged in or on
the
hull 2, for example power supply, communication, navigation and drive devices.
The operating devices which are not illustrated in any more detail are
controlled
by a control device 3 of the underwater vehicle according to predefinable
control
commands. The underwater vehicle 1 also comprises suitable sensors, for
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example sonar sensors, the measurement results of which are used by the
control device 3 to control the operating devices, for example for the purpose
of
navigation.
The unmanned underwater vehicle 1 has a main drive 4 in the region of its
stern
5, which drive acts in a longitudinal direction 6 of the underwater vehicle 1.
In
addition to the main drive 4, the underwater vehicle 1 has a manoeuvring drive
7
which acts in a direction which differs from the longitudinal direction 6 and
enables accurate positioning at the specific place of use during a mission of
the
underwater vehicle 1. In the exemplary embodiment shown, the manoeuvring
drive 7 is in the form of a lateral drive and is arranged in the region of the
bow 8
of the underwater vehicle 1. In this case, manoeuvring drives 7 are preferably
respectively arranged on both sides of the hull 2. As an alternative or in
addition
to lateral drives, one or more lifting drives may be provided as a manoeuvring
drive 7.
The unmanned underwater vehicle 1 can be operated either in an autonomous
operating mode or in a remotely controlled operating mode, a human operator
predefining control information for the control device 3 in the remotely
controlled
operating mode. The control information may be control commands for carrying
out specific manoeuvres which are carried out by the underwater vehicle in
real
time under the guidance of the operator. For this purpose, the underwater
vehicle
1 is connected to the system platform via a connection cable 9 which is
preferably a fibre optic cable. In the exemplary embodiment shown, the system
platform is a mother ship 10, namely a surface ship. In other exemplary
embodiments which are not shown, the system platform is stationary or is
formed
by a submarine as the mother ship.
As an alternative to a connection cable, a wireless communication medium may
be provided. In this case, the communication device 11 wirelessly communicates
with the system platform by radio, sound or in a similar manner.
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The connection cable 9 can be connected to a communication device 11 of the
underwater vehicle 1, with the result that external control commands or other
control information can be predefined to the control device 3 via the
connection
cable 9 and the communication device 11 in the remotely controlled operating
mode. The underwater vehicle 1 also delivers information to the mother ship 10
via the communication device 11, for example image information, with the
result
that manoeuvres can be remotely controlled under real-time conditions in the
remotely controlled mode.
In order to connect the connection cable 9, the underwater vehicle 1 has a
cable
receptacle 12 which is in the form of a plug-in connection in order to simply
adapt
the connection cable 9. For adaptation of the connection cable 9, the end of
the
connection cable 9 is inserted into the cable receptacle 12 in the direction
of the
arrow and is connected to the communication device 11 so as to transmit
signals.
The cable receptacle 12 is advantageously arranged in the region of the stern
5
of the underwater vehicle 1, with the result that the connection cable 9 is
pulled
behind the underwater vehicle 1 during the mission.
In an autonomous operating mode of the unmanned underwater vehicle 1,
predetermined internal control information from a memory element 13 is
predefined to the control device 3, as a result of which the underwater
vehicle 1
can operate autonomously, that is to say independently of the system platform
and a human operator. The control information is predefined by programmed
operating software and/or mission programming and contains both control
information relating to fundamental parameters of the mission and control
commands for manoeuvres in events which cannot be specifically predicted but
the type of which can be determined. For example, control commands for
evasion manoeuvres and control information for (temporarily) changing the
intended patrol of the underwater vehicle in favour of more detailed local
investigations are provided.
An underwater vehicle 1 which can be operated either autonomously or in a
remotely controlled manner combines the advantages of the conventional
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autonomous underwater vehicles (AUV) and of the conventional remotely
controlled underwater vehicles (ROV) in a single underwater vehicle 1. In this
case, the underwater vehicle can be used in a versatile manner both as an
autonomous underwater vehicle (AUV) and as a remotely controlled underwater
vehicle (ROV).
Preferred intended uses of the underwater vehicle 1 according to the invention
which can be operated either in an autonomous operating mode or in a remotely
controlled operating mode are the underwater inspection of harbour facilities,
for
example sheet pile walls, in particular with regard to the undermining of
harbour
walls or sheet pile walls. Further intended uses are the inspection of hulls
or
channel walls such as pipelines or any other use in which the underwater
vehicle
1 is intended to cover the object to be inspected over a relatively long
distance in
the autonomous mode as an AUV and is intended to carry out closer inspection
at locations of particular interest as an ROV in the remotely controlled mode.
In order to selectively set the operating mode or change between the
autonomous operating mode and the remotely controlled operating mode, the
underwater vehicle 1 comprises an operating mode selection means 15 which
generates a corresponding operating mode selection signal 14 in order to set
the
selected operating mode and predefines said signal to the control device 3. In
the
exemplary embodiment according to Fig. 1, the mode selection means 15 is in
the form of an operating mode switch which can be manually operated and is
arranged on the hull 2 of the underwater vehicle 1 such that it is accessible
from
the outside.
The underwater vehicle 1 has controllable manipulation devices 16 for carrying
out manipulation tasks under water, for example repair work. The manipulation
devices 16 are preferably robot arms which are controlled by the control
device
3. In the exemplary embodiment shown, the robot arms are arranged in the
region of the bow 8 but, in other exemplary embodiments which are not shown,
further or other manipulation devices 16 may also be arranged in other regions
of
the underwater vehicle 1. The robot arms can be used to carry out accurately
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controllable manipulation tasks, for example repair work or the collection of
samples which can be stored in a receiving device 17, in particular in the
remotely controlled mode. The receiving device 17 can also be used to
transport
and/or store objects, for example explosive charges.
The underwater vehicle according to the invention which can be operated either
in the autonomous mode or in a remotely controlled operating mode makes it
possible to cover all fields of use of the previous autonomous underwater
vehicles (AUV) and the remotely controlled underwater vehicles (ROV) using a
single underwater vehicle. A single recovery device 18 on board the mother
ship
10 is also sufficient to put the underwater vehicle 1 into the water and to
recover
it after the mission. A single underwater vehicle 1 and the associated
recovery
device 18 considerably reduces, namely approximately halves, the amount of
training needed for handling the underwater vehicle 1 and the recovery device
18
and the space requirement on board the mother ship 10 in comparison with the
conventional solutions with a plurality of vehicle types. The costs for
investigations of underwater areas are considerably reduced by the lower
outlay
on equipment and training and the reduced space requirement.
Fig. 2 shows another exemplary embodiment of an unmanned underwater
vehicle 1'. The same reference symbols as in Fig. 1 are used for the same
features or components in each case. Apart from the differences described in
more detail below, the underwater vehicle 1' corresponds to the design of the
underwater vehicle 1 in Fig. 1.
Instead of the manually operable operating mode switch according to Fig. 1,
the
underwater vehicle 1' according to Fig. 2 comprises a remotely controllable
operating mode selection means 15'. In the exemplary embodiment shown, the
remotely controllable operating mode selection means 15' is a receiver which
responds to a remote control signal representing the wish to change or set the
operating mode. In order to initiate a change of the operating mode of the
underwater vehicle 1', the mother ship, for example, emits the remote control
signal, for example by sound or radio or in a similar manner. When a remote
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control signal is received, the receiver of the mode selection means 15'
responds
such that an operating mode selection signal 14 is supplied to the control
device
3. In an exemplary embodiment which is not shown, the mode selection means
15' and the communication device 11 are connected to a common wireless
communication medium.
In an exemplary embodiment which is not illustrated, the remotely controlled
mode selection means can be remotely controlled via a connection cable. The
connection cable for remote control is preferably a fibre optic cable, the
io connection cable for remote control being the connection cable 9 of the
underwater vehicle 1' for communication with the system platform in the
remotely
controlled mode in the preferred exemplary embodiment. The mode selection
means 15' and the communication device 11 are thus connected to a common
connection cable 9, thus reducing the structural complexity.
Fig. 3 shows another exemplary embodiment of an unmanned underwater
vehicle 1 ". The same reference symbols as in Fig. 1 and Fig. 2 are used for
the
same features or components in each case. Apart from the differences described
in more detail below, the underwater vehicle 1" corresponds to the design of
the
underwater vehicle 1 in Fig. 1.
In the unmanned underwater vehicle according to Fig. 3, either the autonomous
operating mode or the remotely controlled operating mode is set according to
the
specification of operating software 19 of the underwater vehicle and/or a
mission
programme. In this exemplary embodiment, information for changing the
operating mode between the autonomous mode and remotely controlled mode is
part of the control information predefined to the control device 3.
The operating software 19 and the intended mission programme are stored in the
memory element 13 to which the control device 3 has access. In this case, the
memory element 13 may be part of the control device 3.
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The operating software 19 may be specified in terms of any operating mode
changes by a mission programme which has been individually created for
particular missions and has been stored. When changing over between the
operating modes according to the specification of the mission programme, for
example, the time at which the operating mode is changed or else the order in
which an operating mode is changed lies in a sequence of programmed
manoeuvres of the underwater vehicle 1 ".
When the operating software 19 sets the operating mode, the operating mode is
preferably changed during the mission if the operating software determines,
from
the results from measuring devices of the underwater vehicle 1 ", the presence
of
a particular situation for which a change to the respective operating mode
other
than the current operating mode is provided. In this case, the intelligent
operating
software assesses the continuously arriving measured values from the sensor
devices with regard to possible operating mode changes. The operating software
comprises corresponding assessment algorithms for this purpose. The
assessment algorithms may be determined or specified by the mission
programme.
All of the features mentioned in the abovementioned description of the
figures, in
the claims and in the introductory part of the description can be used both
individually and in any desired combination with one another. Therefore, the
disclosure of the invention is not restricted to the described and/or claimed
combinations of features. Rather, all combinations of features should be
considered to be disclosed.
