Note: Descriptions are shown in the official language in which they were submitted.
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AN INSTALLATION AND A METHOD FOR RECOVERING A SURFACE
MARINE VEHICLE OR AN UNDERWATER VEHICLE
The invention relates to an installation and a
method for recovering a surface marine vehicle or an
underwater vehicle that is in the water, from a recovery
base.
The installation may be used in particular for
recovering an autonomous underwater vehicle (AUV).
An installation is already known that enables an AUV
in the water to be recovered from a boat, the
installation comprising a ramp having one end hinged to
the stern of the boat and having its other end floating
on the surface of the water. A winch mounted on the boat
pulls the AW via its nose (i.e. its front end) by means
of a cable in order to pull it up along the ramp.
That known installation presents the following
drawbacks. Firstly, it is necessary to align the AW
properly with the ramp, and in practice this can be found
to be difficult, in particular in rough water, since the
boat is oscillating (pitching, rolling, heaving) and it
entrains the ramp together therewith so the ramp is
continuously changing its alignment. Furthermore, high
stresses are exerted on the AUV while it is being pulled
along the ramp, and that runs the risk of damaging the
AUV. Finally, that type of installation is not suitable
for recovering AUVs having fins since the fins would be
damaged while the AUV is sliding on the ramp.
An object of the invention is to propose an
installation enabling a surface marine vehicle or an
underwater vehicle to be recovered easily from the water
without running the risk of damaging it.
This object is achieved by an installation for
recovering a surface marine vehicle or an underwater
vehicle in water, from a recovery base, the installation
being characterized in that it comprises a floating cage
defining a housing in which at least a portion of said
vehicle can penetrate, first puller means mounted on said
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cage and capable of pulling said vehicle into said
housing via a first flexible connection, and second
puller means designed to be mounted on the recovery base
and capable of pulling said cage via a second flexible
connection distinct from the first.
This installation can be used for recovering various
types of vehicle, whether floating or in controlled
immersion, and in particular an AW, a torpedo, a surface
drone, or a vehicle of similar architecture. In general,
it is used for recovering a vehicle floating on the
surface of the water. Furthermore, the recovery base may
be a boat, a quay, an off-shore platform, etc.
The term "flexible connection" is used to designate
any type of connection capable of tensioning and relaxing
as a function of the traction exerted thereon. When it
is relaxed, the second flexible connection allows the
cage to move freely relative to the recovery base. More
particularly, when the recovery base is a boat, this
avoids the boat entraining the cage together therewith
when the boat is oscillating (in pitching, rolling,
heaving). This makes it easier to bring the vehicle into
alignment with the cage into which it is to penetrate.
Typically, the flexible connections of the
installation are cables, and the puller means comprise
cable winder devices for winding cable in and out.
In an embodiment, the cage is fitted with means for
receiving, guiding, and determining the orientation of
said vehicle as it penetrates into the cage. This makes
it easier to bring the cage and the vehicle into
alignment, and also makes it easier for the vehicle to
penetrate into the cage. These various means are
described in detail below.
when the vehicle has fins, the shape of the cage is
adapted accordingly: for example, its sides may present
lateral openings into which the fins can pass.
The first and second puller means enable the
distance between the vehicle and the cage and the
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distance between the cage and the recovery base to be
controlled independently, thereby enabling these
distances to be adapted as a function of operating
conditions.
Advantageously, the first puller means are
controlled remotely from the recovery base.
The second puller means are generally mechanical
means, but if the weight of the cage plus the vehicle
makes this possible, they could be constituted by
operators pulling manually on the second flexible
connection. A plurality of flexible connections can be
used for pulling the cage from the recovery base.
In an embodiment, handling means are used in
association with the second puller means mounted on the
recovery base, the handling means likewise being mounted
on said base. They may be constituted by a crane, a
gantry, or a jib. The second puller means and the
handling means serve to enable the cage and the vehicle
to be hoisted onto the recovery base and make it easy for
them to be placed on a appropriate support.
The invention also provides a method of recovering a
surface marine vehicle or an underwater vehicle in water,
from a recovery base, the method comprising: launching a
floating cage of the above-specified type that defines a
housing in which at least a portion of said vehicle can
penetrate; pulling said vehicle into said housing with
the help of first puller means mounted on said cage and
connected to said vehicle via a first flexible
connection; and pulling said cage together with said
vehicle using second puller means mounted on the recovery
base and connected to said cage via a second flexible
connection distinct from the first.
In an implementation of the recovery method, prior
to launching said cage, said first flexible connection
connected to the vehicle is recovered in the water from
the recovery base, e.g. with the help of a boat-hook.
The first flexible connection is then connected to the
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first puller means of the cage, while the cage is on the
recovery base. Only thereafter is the cage launched, it
being understood that the cage is launched while being
connected to the second puller means via the second
flexible connection. In this method, there is no need at
any time to call on divers, thereby achieving savings in
terms of time and human resources.
In another aspect, the invention provides a method
of launching or underwater vehicle from a launching base.
A method of the above-specified type is already
known that makes use of a ramp hinged to the stern of the
launching base. In that method, the vehicle (an AW) is
caused to slide along the ramp in order to launch it.
With that known method, high stresses are exerted on
the vehicle as it slides along the ramp and as it
penetrates into the water, and that can risk damaging the
vehicle. That phenomenon is even more marked when the
sea is rough, since the ramp then oscillates together
with the boat (pitching, rolling, heaving).
In addition, as mentioned above, the use of a ramp
is not suitable with vehicles that have fins since the
fins run the risk of being damaged when the vehicle
slides on the ramp.
An object of the invention is to provide a method
enabling a surface marine vehicle or an underwater
vehicle to be launched easily from a launching base,
without running the risk of damaging the vehicle.
This object is achieved by a method comprising the
steps of:
= launching a floating cage together with a vehicle
housed at least in part inside the cage, the cage being
connected to the launching base via a flexible
connection; and
= pulling the vehicle out from the cage with the
help of puller means mounted on said cage.
According to the invention, the cage and the vehicle
are launched together. During this step, the vehicle is
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protected by the cage that surrounds and the vehicle is
subjected to low levels of stress only.
Since the cage is connected to the launching base
via a flexible connection, once they are in the water,
5 the vehicle and the cage can move freely relative to the
boat so that any oscillations of the boat do not disturb
them. This makes it easy to extract the vehicle from the
cage.
In an implementation of the method, the vehicle is
held relative to the cage while the cage is being
launched, and until the vehicle is released with the help
of release means. This makes it possible to avoid
impacts occurring between the cage and the vehicle during
launching.
The vehicle is finally released (if it was
previously held relative to the cage) and is then pulled
out from the cage. Advantageously, these last two
actions are remotely controlled from the launching base.
The invention and its advantages can be better
understood on reading the following detailed description.
The description is given with reference to the
accompanying sheets of figures, in which:
= Figures 1 to 3 show an example of a recovery
installation of the invention respectively in side view,
plan view, and end view;
= Figure 4 shows the installation of Figures 1 to 3
in side view when the vehicle for recovery is taken out
of the water;
= Figures 5 to 7 show, in part only, an example of
recovery apparatus of the invention, respectively in side
view in longitudinal section, in plan view, and in end
view; and
= Figure 8 shows the apparatus of Figures 5 to 7
being used, in this example, to launch a vehicle.
The installation of Figures 1 to 4 serves to recover
a vehicle 1 from the water and/or to launch it.
By way of example, the vehicle 1 is an AUV that is
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torpedo-shaped. It should be observed that it has two
large side fins in its middle portion.
The installation comprises a boat 5 as a recovery
base. The boat 5 is fitted with a winch 7 for winding a
cable 9 in and out. The cable is preferably a textile
cable.
The installation also comprises a recovery apparatus
within which the vehicle 1 can be received, at least in
part.
To refer to the recovery apparatus, the term "cage"
10 is used below. The cage 10 is fitted on its sides
with floats 12 that enable it to remain at the surface of
the water and to adjust its immersion depth.
In a particular embodiment, the floats 12 are
connected to said cage via hinges that allow the floats
to flap up and down. On the surface of the water, the
floats thus move away from the cage so as to maximize
stability and avoiding impeding entry of the vehicle 1.
Advantageously, when not in the water, the floats 12
extend along the cage 10 on either side thereof in such a
manner as to protect it (and also the vehicle 1) from
possible lateral impacts. Such lateral impacts may
occur, in particular, while the cage 10 is being hoisted
on board the boat 5. The floats 12 are for example boat
fenders.
The cage 10 comprises:
= A frame 14 defining a housing 16 with an entrance
through which the vehicle 1 can penetrate. In Figures 1
and 2, this entrance is to the right of the cage, and in
Figure 3, the entrance is seen end on.
= Receiver means 18 suitable for receiving the front
portion of the vehicle 1, referred to below as its
"nose". The receiver means 18 define a cavity 20 of
shape that is complementary to the shape of the nose of
the vehicle 1. These receiver means 18 have a cable 22
passing therethrough, a passage 23 being formed for this
purpose in the receiver means 18 through the end of the
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cavity 20 (see Figures 5 and 7).
= Guide means for guiding and aligning the receiver
means 18 together with the vehicle 1 relative to the
frame 14 so as to facilitate penetration of the vehicle 1
into the cage 10.
= Puller means fastened to frame 14 enabling the
vehicle 1 to be pulled into the housing 16 inside the
cage 10, via a flexible connection, typically the cable
22, connected to the vehicle 1. These puller means
comprise a winder device for winding the cable 22 in
and/or out, which device is formed by a winch 24. The
cable 22 may be a textile cable or a metal cable. The
winch 24 may be remotely controlled, and in particular
controlled from the boat.
. Holder means for holding the vehicle 1 inside the
housing 16 and suitable for preventing the vehicle 1 from
moving back out from the cage 10 once it has entered it.
= At least one energy source (e.g. at least one
battery 25) for powering the puller means and, if
necessary, the holder means. It is possible to provide
holder means that are not powered with energy, being
triggered mechanically by the vehicle 1 going past.
It should be observed that Figures 5 to 9 do not
show all of the portions of the cage 10. In particular,
the bottom portions of the cage are not shown. These
figures seek to show more particularly the reception
means and the guide means.
Said reception means 18 comprise an element 32 that
is movable between the entrance and the end of the cavity
20. The cable 22 passes through this movable element 32,
preferably through its center. In this example, the
movable element 32 comprises a cup 34 suitable for
receiving the nose of the vehicle 1 (see Figure 7), and
presenting a central hole 35 through which the cable 22
passes. A plurality of guide branches 36 (generally at
least two diametrically-opposite branches) extend from
the periphery of the cup 34 and connect it to the
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structure 37 of the reception means 18. The end of each
branch 36 can slide relative to said structure 37 so that
the movable element 32 can slide between the entrance and
the end of the cavity 20, as represented by double-headed
arrow A in Figure 5.
The cage 10 includes first blocking means 38 (see
Figure 5) for holding said reception means 18 in the
vicinity of the entrance to the housing 16, before the
vehicle 1 reaches the cage. Thus, said reception means
18 are in position for receiving the vehicle 1 when it
arrives. In addition, insofar as the vehicle 1 is being
pulled and is coming closer, the portion of the cable 22
that extends between the winch 24 and the reception means
18 (more precisely between the pulley 40, the passage 23,
and the nose of the vehicle 1 - see Figures 5 and 6)
forms a lever arm that serves to cause the cage 10 to
point towards the nose of the vehicle 1, thereby making
it easier to recover. It should be observed that the
cage is capable of being aligned since it can move freely
in the water, the cable(s) 9 (70) connecting the cage 10
to the boat 5 being slack.
The first blocking means 38 release said reception
means 18 only when the nose of the vehicle 1 is fully
engaged in the reception means 18 (more precisely in the
cavity 20) and is about to penetrate into the housing 16.
In this example, the first blocking means 38 comprise an
abutment capable of retracting when the vehicle 1 exerts
a thrust force thereon that is greater than a
predetermined force. In practice, the abutment is formed
by an arm 42 pivotally mounted on the frame 14, with a
wheel 46 mounted at the end of the arm. The arm 42 is
connected to a spring 44 of stiffness that is selected
such that beyond a certain thrust force exerted by the
vehicle 1 on the arm 42 via the reception means 18, the
spring 44 deforms and allows the arm to retract by
pivoting as represented by arrow B (see Figure 5). Other
types of blocking means could naturally be envisaged.
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The cage also has second blocking means 48 (see
Figure 6) for holding the moving element 32 of the
reception means 18 at the entrance of the cavity 20,
these second blocking means 48 releasing the movable
element 32 when the vehicle 1 comes into contact with the
movable element 32 (more precisely with the cup 34). By
way of example, these second blocking means 48 operate on
the same principle as the first blocking means 38 and
comprise an abutment capable of retracting when the
vehicle 1 acts thereon, via the movable element 32, to
exert a thrust force that is greater than a predetermined
force.
The presence of the movable element 32 and the
blocking of the movable element at the end of the cavity
20 enable the portion of cable 22 that is tensioned
between the end of the cavity 20, the entrance to said
cavity, and the nose of the vehicle 1, to behave like a
lever arm, thereby pointing said cavity 20 to face the
vehicle 1, as the vehicle approaches. This makes the
vehicle easier to recover.
The blocking force of the second blocking means 48
is less than the blocking force of the first blocking
means 38, such that when the vehicle 1 penetrates into
the reception means 18 (more precisely into the cavity
20), the second blocking means 48 give way before the
first blocking means 38 give way.
Said reception means 18 are secured to a rod 50.
when the cage 10 is in the water and floating, the rod 50
extends vertically (relative to the horizontal defined by
the water). The rod 50 is mounted on a carriage 52 so as
to be capable of pivoting about its axis C as represented
by double-headed arrow D in Figures 5 to 7. The carriage
52 is guided along the housing 16 of the cage 10 by said
guide means.
The reception means 18 are mounted on the rod 50 in
such a manner:
= as to be driven by the rod 50 when it pivots as
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represented by double-headed arrow D, referred to below
as "horizontal" pivoting; and
= as to be capable of pivoting about an axis
perpendicular to the axis C of the rod, as represented in
5 Figures 5 and 7 by double-headed arrow E, referred to
below as "vertical" pivoting.
These freedoms to move in vertical and horizontal
pivoting enable the reception means 18 to point to face
the nose of the vehicle 1 as it approaches, and once the
10 nose of the vehicle 1 is received in the cavity 20, to
follow the oscillations of the vehicle 1, until it comes
to bear against the cradles of the rocker 29 (described
below).
In this example, the bottom end of the rod 50
carries a fork 51, and between the two branches of the
fork 51 there extends an axis F perpendicular to the axis
C of the rod, about which the reception means are
pivotally mounted. Abutments 53 limit the vertical pivot
angle of the reception means 18.
A guide arm 54 is fastened to the end of the rod 50
so as to enable it to be entrained and pivoted about its
axis C as represented by double-headed arrow D. The arm
54 presents a first end engaged with the rod 50 and a
second end having a wheel 56 mounted thereon.
Said guide means comprise first and second
superposed guides 58 and 60 extending along the housing
16.
The first guide 58 guides the carriage 52 along the
housing 16. It is formed by a pair of parallel rails 64,
and the carriage 52 is fitted with wheels 62 enabling it
to move along the rails 64 as represented by double-
headed arrow G shown in Figure 6.
The second guide 60 guides the guide arm 54 and, as
a result, turns the rod 50 and the reception means 18 by
causing them to pivot horizontally as represented by
double-headed arrow D. It is situated above the first
guide 58. It is formed by a pair of rails 66 that come
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closer to each other on going away from the entrance to
the cage 10. The guide arm 54 can pivot between these
rails 66 as represented by double-headed arrow D, between
a first position in which the wheel 56 is in contact with
one of the rails 66, and a second position in which the
wheel 56 is in contact with the other rail 66. The
greater the spacing between the rails 66 the greater the
freedom of the arm 54, and thus of the rod 50 and of the
reception means 18 to pivot horizontally. Conversely,
the further the vehicle 1 penetrates into the cage 10,
the more the carriage 52 advances along the rails 66 that
approach each other, and the smaller the freedom of the
reception means 18 to pivot horizontally. Thus, as the
vehicle 1 penetrates into the cage 10, the arm 54 and the
reception means 18 are brought progressively into
alignment along the main axis H of the cage 10. The
reception means 18 entrain the vehicle 1 via its nose,
and the vehicle 1 is likewise brought into alignment
along the axis H (see Figure 6). It thus penetrates
easily into the cage 10.
In its sides, the frame 14 of the cage 10 presents
notches 68 that are open towards the entrance of the cage
10, serving to allow the lateral fins 3 of the vehicle 1
to pass therethrough (see Figures 1 and 4). Since the
vehicle 1 is guided and correctly aligned on penetrating
into the cage 10, the fins 3 are received in the notches
68 and are therefore not damaged.
In this example, said holder means comprise two rods
26 fitted with shoes at their ends, together with a
mechanism for raising/lowering the rods. The rods 26
slide inside two boxes 28 containing said mechanism.
These boxes 28 are fastened on either side of the frame
14 in the vicinity of the entrance to the cage 10. In
the lowered position, the rods 26 are in contact with the
top face of the vehicle 1, as shown in Figures 4 and 8.
It should be observed that the pressure exerted by the
rods 26 on the vehicle 1 needs to be controlled so as to
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avoid damaging the vehicle.
In another embodiment (not shown), the holder means
comprise a rod that is pivotally mounted on the frame 14
together with a mechanism, e.g. an actuator, for causing
the rod to pivot. At its end, the rod carries a cradle
that surrounds the top face of the vehicle 1. The
vehicle 1 may possibly present a member that projects
from its top face. After the vehicle has penetrated into
the housing 16, the cradle is lowered and takes up
position behind the projecting member, thereby enabling
the vehicle 1 to be held inside the cage 10.
Other types of holder means could be envisaged.
Advantageously, such means are remotely controlled, and
preferably they are controlled from the boat 5.
Furthermore, the bottom face of the vehicle 1 bears
against a rocker 29 mounted on the frame. This rocker 29
carries at each of its ends a respective cradle 30 on
which the vehicle 1 rests. As shown in Figures 1 and 3,
the cradles 30 extend transversely relative to the cage
10, under the housing 16. These cradles are easily
withdrawn when the vehicle 1 is placed on a suitable
working support present on the boat 5.
An example of the method for recovering a surface
marine vehicle or an underwater vehicle from a recovery
base is described below, which method makes use of the
above-described cage 10. In this example, the recovery
base is the boat 5, and the vehicle to be recovered is
the vehicle 1.
Depending on the embodiment of the vehicle 1 and
depending on operating circumstances, a cable 22'
connected to the nose of the vehicle 1 is recovered from
on board the boat 5. Thereafter, the cable 22' is
connected to a cable 22" that is waiting in the cage 10.
The cables 22' and 22" then form the above-mentioned
cable 22 that is caused to pass through the movable
element 32, the passage 23 in the reception means 18, and
around the pulley 40 situated at the end of the housing
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16, and that is connected to the winch 24 of the cage 10
(see Figure 5).
In the following step, the cage 10 is launched into
the water. It remains connected to the boat 5 via the
traction cable 9, also referred to as hoist cable, and
via other cables 70 referred to as guide cables. At this
stage, the cables 9 and 70 are relaxed such that the boat
5 does not entrain the cage 10 in its own movement. The
cage 10 thus moves freely in the water.
In the following step, the winch 24 is remotely
controlled to wind in the cable 22 so as to pull the
vehicle 1, the reception means 18 situated at the
entrance of the cage 10, and the winch 24 (in fact the
pulley 40) situated at the end of the cage 10, forms a
lever arm that causes the cage 10 to turn so that the
axis H of the cage approaches the nose of the vehicle 1.
In the same manner, the reception means 18 turn to face
the nose of the vehicle 1 as it approaches because of the
length of the cable 22 that extends from the end of the
cavity 20 (i.e. the passage 23), via the movable element
32, to the nose of the vehicle 1.
The nose of the vehicle 1 initially comes into
contact with the movable element 32, and as traction
continues on the vehicle 1 it exerts thereon an ever
increasing thrust force. Beyond a limit force, the
second blocking means 48 release the movable element 32,
which then moves in translation together with the nose of
the vehicle 1 to the end of the cavity 20. The nose of
the vehicle 1 then occupies the cavity 20. Relative
movements between the reception means 18 and thus the
vehicle 1 and the cage 10 are still allowed at this
stage. The reception means can pivot vertically and
horizontally as represented by double-headed arrows E and
D. This limits the stresses that are exerted on the nose
of the vehicle 1, associated with the relative movement
between the vehicle 1 and the cage 10.
As traction continues, the vehicle 1 exerts an ever
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increasing thrust force on the reception means 18.
Beyond a limit force, the first blocking means 38 release
the carriage 52 to which the reception means 18 are
connected via the rod 50. The carriage 52 then runs
along the first guide 60 towards the end of the housing
16. Simultaneously, the guide arm 54 is guided along the
first guide 58 and its freedom to move as represented by
double-headed arrow D decreases progressively. The
reception means 18 and the vehicle 1 thus become
progressively aligned along the main axis H of the cage.
Once the nose of the vehicle 1 reaches the end of
the housing 16, the rods 26 are remotely controlled to
move down so as to hold the vehicle 1 in the cage. In
this example, it should be observed that only a fraction
of the vehicle 1 penetrates into the cage 10.
In the following step, the cage 10 together with the
vehicle 1 is pulled by the cable 9 towards the boat 5 in
order to be hoisted on board the boat 5. The guide
cables 70 can also be used for pulling the cage 10 and
the vehicle 1. For this purpose, the guide cables 70 can
be pulled by hand or they may be connected to a cable
winder device, e.g. winches analogous to the winch 7.
Under such circumstances, the cables 70 and their winder
devices form part of the puller means mounted on the
recovery base, in the meaning of the invention.
When, as in this example, the cable 9 is associated
with a gantry crane 72, the guide cables 70 are used to
direct the cage 10 and the vehicle 1 so as to pass
through the gantry 72. The cage 10 and the vehicle 1 are
extracted from the water using the cable 9, while the
cables 70 are used for guiding and passing the cage 10
and the vehicle 1 through the gantry 72 prior to placing
them on the deck of the boat 5.
An example of the method for launching a vehicle
from a recovery base is described below, which method
makes use of the above-described cage 10.
In this example, the recovery base is the boat 5 and
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the vehicle to be recovered is the vehicle 1. To begin
with the vehicle 1 is held in the cage 10 and the cage is
on board the boat 5.
In a first step, the winch 7, the traction cable 9,
5 the gantry crane 72, and possibly the guide cables 70 are
used to launch the cage 10.
Once the cage 10 is in the water, the vehicle
previously held relative to the cage 10 (by the above-
mentioned holder means) is released with the help of
10 release means. In this example, the release means
comprise a mechanism enabling the rods 26 to be raised.
These release means are controlled remotely,
advantageously from the launching base (i.e. the boat 5).
In the following step, the vehicle 1 is pulled out
15 from the cage 10 with the help of puller means mounted on
the cage. With reference to Figure 8, these puller means
comprise a cable winder device, i.e. the winch 24 and the
cable 22 as described above, together with a pulley 74
situated level with the entrance to the housing 16 of the
cage 10. The cable 22 is connected to the winch 24,
extends as far as the pulley 74, passes round the pulley,
and extends back to the carriage 52 to which it is
connected. To extract the vehicle 1 from the cage 10,
the winch 24 is actuated so that the carriage 52, the
reception means 18, and the nose of the vehicle 1 are
pulled by the cable 22 towards the entrance of the
housing 16. When the reception means 18 come close to
the entrance of the housing 16, their freedom to move in
pivoting (associated with the freedom of the guide arm
54) increases because of the wider spacing between the
rails 66 of the second guide 60. Thus, the freedom of
the vehicle 1 to move relative to the cage 10 increases
as the vehicle 1 is extracted from the cage 10, thereby
limiting or even avoiding mechanical stresses appearing
in the nose of the vehicle 1. Said puller means are
controlled remotely, advantageously from the launching
base. When the vehicle 1 is fully extracted from its
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housing, it moves away from the cage 10 on its own since
it is no longer connected thereto.
Depending on operating conditions, the vehicle 1 may
be secured to the reception means 18 until the end of the
extraction movement. It is then finally released either
on command from the boat 5, as is advantageous, or else
by means of a mechanical device placed on the reception
means 18 and triggered automatically at the end of the
stroke of said reception means.
It should be observed that in the above-described
examples of the recovery method and of the launching
method, there is no need for divers to intervene, the
various steps of the method being capable of being
performed on the boat 5 or of being controlled therefrom.
