AU2018396084A1

AU2018396084A1 - Submarine device

Info

Publication number: AU2018396084A1
Application number: AU2018396084A
Authority: AU
Inventors: Christophe Borel; Jean-Philippe Brunet; Franck Florin
Original assignee: Thales SA
Current assignee: Thales SA
Priority date: 2017-12-28
Filing date: 2018-12-28
Publication date: 2020-04-23
Also published as: CA3084653A1; WO2019129853A1; EP3732095B1; FR3076279B1; EP3732095A1; FR3076279A1

Abstract

Submarine device (E) comprising a submarine vehicle (1), the submarine vehicle (1) comprising a body (10) of the submarine vehicle (1), the submarine device (E) comprising a connection element (4) connected to the body (10) of the submarine vehicle (1) and being able to cooperate with a cable to react a traction force (F) exerted by the cable (3) on the submarine vehicle (1), the connection element being connected to the body of the vehicle and being configured such that the axis of the traction force (F) is able to move with respect to the body (10) of the vehicle and is able to have different orthogonal projections in a plane P that is fixed with respect to the body (10) passing through the center of mass (G) of the submarine vehicle (1).

Description

SUBMARINE DEVICE

The field of the invention is that of underwater vehicles, namely that of vehicles that are able to be entirely submerged.

It relates in particular to unmanned underwater vehicles, or UUVs.

These vehicles can be equipped with synthetic aperture sonars (SAS) for exploring the seabed. These sonars are used in particular in the field of mine warfare in order to detect, identify and optionally locate the objects placed on the seabed.

Currently, underwater acoustic imaging is effected:

- either from a towfish (underwater vehicle without a thruster) that is provided with a sonar and is towed by means of an electric hauling cable, by a surface vessel, such as a surface ship; the sonar is electrically powered by the surface vessel via the electric hauling cable and the data are transmitted to the surface by the electric hauling cable in order to be processed in real time on board the surface vessel and/or transmitted via radio to an onshore processing center,

- from an underwater vehicle provided with a thruster, which is used as a remote operated vehicle, or ROV. This vehicle is connected to a surface vessel by a cable. The surface vessel electrically powers the thruster of the underwater vehicle and the sonar via the cable, which transmits the sonar data to the surface through the cable in order to be processed in real time on board the surface vessel and/or transmitted via radio to an onshore processing center. This vehicle usually operates at slow speed, since the cable exerts a pulling force on the underwater vehicle even if the cable is not taut,

- or on board an underwater drone that is provided with a thruster powered by batteries fitted on board the vehicle, navigates autonomously and records the data on board, the data only being transmitted to equipment outside the vehicle at the mission end.

Good stability of the vehicle is required in order to detect, identify and locate with precision the objects placed on the seabed.

Underwater vehicles are conventionally connected to the surface vessel by a cable attached to one longitudinal end of the underwater vehicle. The pulling force exerted by the cable on the underwater vehicle is exerted at the point at which the cable is fastened, that is to say at the longitudinal end of the underwater vehicle. Thus, as soon as the surface vessel starts to pull the underwater vehicle, this destabilizes the underwater vehicle, the attitude of which, in particular the pitch, varies. It is necessary to provide means, for example rudders and/or a thruster, for stabilizing the underwater vehicle, for example to allow it to remain at a given depth and to allow it to maintain a stable pitch when it is towed by the surface vessel. The power rating of these stabilizing means has to be higher, the greater the weight of the underwater vehicle.

One solution for limiting the problems of instability of the underwater vehicle is described in the American patent US 7,775,174. It consists in providing coordinated control of the surface vessel and of the underwater vehicle in order to decouple the movements of the two from one another as much as possible.

An aim of the invention is to propose a simplified solution.

To this end, the subject of the invention is an underwater machine comprising an underwater vehicle, the underwater vehicle comprising a body of the underwater vehicle, the underwater machine comprising a linking element that is connected to the body of the underwater vehicle and is able to cooperate with a cable to take up a pulling force exerted by the cable on the underwater vehicle, the linking element being connected to the body of the vehicle and being configured such that the axis of the pulling force is movable with respect to the body of the vehicle and able to exhibit different orthogonal projections in a fixed plane P with respect to the body that passes through the center of inertia of the underwater vehicle.

Advantageously, the linking element is connected to the body of the underwater vehicle by a link having at least one degree of rotational freedom about an axis of rotation such that the pulling force exerted by the cable on the underwater vehicle is able to pivot about the axis of rotation, the projection of the axis of the pulling force on the plane P being radial to the axis of rotation.

Advantageously, the linking element is configured and connected to the body such that when the cable cooperates with the linking element, the projection of the axis of the pulling force on the plane passes through the center of inertia of the underwater vehicle regardless of the orientation of the pulling force about the axis in an angular work sector with a predetermined non-zero opening.

Advantageously, the underwater machine comprises at least one of the following features, on their own or in combination:

- the center of inertia of the underwater vehicle and the center of buoyancy of the underwater vehicle are situated in the plane P,

- a main axis of movement of the vehicle is parallel to the plane P and perpendicular to a straight line passing through the center of buoyancy and the center of inertia of the underwater vehicle,

- the body of the underwater vehicle extends longitudinally along the main axis of movement,

- the axis of rotation is fixed with respect to the body of the underwater vehicle,

- the linking element is connected to the body of the underwater vehicle by a link having one degree of freedom,

- the axis of rotation is able to be moved with respect to the body of the underwater vehicle,

- the underwater machine comprises blocking means for immobilizing the axis of rotation with respect to the body of the underwater vehicle in a position in which the axis of rotation passes through the center of inertia,

- the link comprises a sliding link connecting the link having at least one degree of rotational freedom to the body, the sliding link being substantially perpendicular to the axis of rotation,

- the direction of the sliding link is parallel to the main axis of movement of the underwater vehicle,

- the axis of rotation is at a distance from the center of inertia of the underwater vehicle and the axis of rotation is movable with respect to the body of the underwater vehicle, the underwater machine comprising adjusting means configured to adjust the position of the axis of rotation on the basis of an orientation of a projection orthogonal to the axis of the pulling force so as to make the orthogonal projection of the pulling force pass through the center of inertia of the underwater vehicle regardless of the orientation thereof in a predetermined angular sector with a non-zero opening angle,

- the adjusting means comprise an actuator for moving the axis of rotation with respect to the body of the underwater vehicle and a control member that is able to control the actuator,

- the link having at least one degree of rotational freedom about the axis of rotation is a pivot link,

- the link having at least one degree of rotational freedom about the axis of rotation is a cardan joint having two axes, namely the axis of rotation and another axis of rotation of the plane P,

- the pulling force has a greater angular displacement about the axis of rotation than about the other axis of rotation,

- the different orthogonal projections of the axis of the pulling force in the plane P are obtained by a movement of the linking element with respect to the body of the underwater vehicle without deformation of the linking element,

- the underwater vehicle comprises a thruster,

- the thruster is a vectorial thruster,

- the underwater vehicle comprises attitude adjusting means for adjusting at least one attitude angle of the underwater vehicle,

- the underwater vehicle comprises an electrical energy accumulator.

The invention will be understood better from studying a number of embodiments that are described by way of entirely nonlimiting examples and are illustrated in the appended drawings, in which:

- Figure 1a shows an underwater vehicle mechanically connected to a surface vehicle, and figure 1b shows an autonomous underwater vehicle,

- Figure 2 schematically shows a first example of the first embodiment of the invention,

- Figure 3 schematically shows a second example of the first embodiment of the invention,

- Figure 4 schematically shows a first example of a second embodiment of the invention,

- Figure 5 schematically shows a second example of the second embodiment of the invention,

- Figure 6 schematically shows means for adjusting the position of the axis of rotation of the second embodiment of the invention.

From one figure to another, the same elements are designated by the same references.

Figure 1a shows an underwater vehicle 1 comprising a body 10 and a thruster 2. The thruster 2 is mounted on the body 10 of the underwater vehicle 1. The thruster 2 is able to propel the underwater vehicle 1.

The underwater vehicle 1 is able to be mechanically connected to a surface vessel 100 as shown in figure 1a, the two vehicles being connected mechanically together by a cable 3.

The surface vessel 100 is, for example, a surface vehicle, that is to say a ship navigating on the surface or an underwater vehicle navigating at a shallower depth than the underwater vehicle 1.

The underwater vehicle 1 can be used as an ROV, that is to say mechanically connected to a surface vessel 100 by means of the cable 3 without being towed by the surface vessel 100, the underwater vehicle 1, which is entirely submerged, ensuring its own propulsion by being propelled by its thruster 2. The relative speed of the underwater vehicle 1 and the surface vessel 100 is, for example, adjusted such that the surface vessel 100 and the underwater vehicle 1 move at the same speed, one of the vehicles being ahead of the other without the cable 3 being taut between the two vehicles 1 and 100. The thruster 2 of the ROV is supplied with electric power via the electric hauling cable 3, either directly or via an electrical energy accumulator of the underwater vehicle.

In one variant, the cable 3 is taut between the two vehicles. This is the case, for example, when the underwater vehicle 1 is towing the surface vessel 100 or vice versa.

As a variant, the vehicle 1 can be detached from the surface vessel 100 and move around independently in the water, as shown in figure 1b. The underwater vehicle 1 is then propelled by its own thruster 2, which is powered by an electrical energy accumulator ACC, 300 of the underwater vehicle 1 shown in figure 2.

The invention relates to an underwater machine E, shown schematically in figure 2, comprising the underwater vehicle 1 shown in the previous figures provided with a linking element 4, which is able to cooperate with the cable 3 so as to make it possible to mechanically connect the underwater vehicle 1 to a surface vessel 100 when the cable 3 is mechanically connected to the surface vessel 100. The cable 3 is then fastened to the linking element 4.

When the cable 3 mechanically connects the underwater vehicle 1 to the surface vessel 100, it is able to exert a pulling force F, shown in figure 2, on the underwater vehicle 1. This pulling force F is directed along an axis I, which is the longitudinal axis of the cable 3 in the vicinity of the linking element 4. The linking element 4 takes up the pulling force F exerted by the body 10 on the underwater vehicle 1.

According to the invention, as shown in figure 2, the linking element 4 is connected to the body 10 of the underwater vehicle 1 by a link 5 that allows the linking element 4 to move with respect to the body 10 of the underwater vehicle 1. Thus, the linking element 4 is movable with respect to the body 10 of the underwater vehicle 1 such that the pulling force F exerted by the cable 3 on the vehicle 1 is movable with respect to the body 10.

According to the invention, the linking element 4 is connected to the body 10 of the vehicle 1 and is configured such that the axis of the pulling force F exerted by the cable 3 on the vehicle is able to exhibit different orthogonal projections in the fixed plane P with respect to the body 10 that passes through the center of inertia G of the underwater vehicle 1. In other words, there are a plurality of different orthogonal projections of the axis of the pulling force F in the plane P. These projections pass through the center of inertia G of the underwater vehicle 1. These different orthogonal projections that pass through the plane P are obtained by virtue of a movement of the linking element 4 with respect to the body 10 of the underwater vehicle and by virtue of the configuration of the linking element. In other words, these different orthogonal projections are obtained for different positions of the linking element 4 with respect to the body 10.

The axis of the pulling force F is the axis of the pulling force taken up by the linking element 4 and exerted by the linking element 4 on the vehicle 1.

In the embodiments in the figures, the linking element 4 does not deform between these different positions. In other words, the linking element 3 does not deform between the different orthogonal projections of the axis of the pulling force F. The linking element 4 passes from one position to another by moving with respect to the body 10, that is to say by the linking element moving in translation and/or rotation with respect to the body 10. In other words, the different axes of the pulling force providing the different orthogonal projections in the plane P are obtained by a movement of the linking element with respect to the body 10 of the underwater vehicle 1 without deformation of the linking element 4.

In the nonlimiting embodiment in the figures, the plane P is the vertical plane passing through the center of inertia G. The axis z is a vertical axis.

The longitudinal axis I of the cable 3 in the vicinity of its fastening point to the linking element 4 is situated on the portion of the cable 3 between this fastening point and the surface vessel 100, in the vicinity of the linking element 4.

For different positions of the linking element 4 with respect to the body 10, the projections, on the plane P, of the longitudinal axis I of the cable 3 in the vicinity of the fastening point of the cable 3 to the linking element pass through the center of inertia G of the underwater vehicle 1. For these different positions, the axis of the pulling force F passes through the center of inertia G when the pulling force F is situated in the plane P. Consequently, when the pulling force F is in the plane P and the linking element 4 in these different positions, the application point of the pulling force F on the underwater vehicle 1 is substantially the center of inertia G of the underwater vehicle 1. The linking element 4 makes it possible for forces of the cable 3 on the center of inertia G of the underwater vehicle 1 to be taken up when the pulling force F is in the plane P and the linking element is in these positions. This configuration allows the underwater vehicle 1 to minimize, if not eliminate, the destabilization of the underwater vehicle 1 when, with the vehicle being used as an ROV, the pulling force F is in the plane P for these different positions of the element 4, for example when the underwater vehicle 1 and the surface vessel are located in the same plane P in the absence of current.

The orientations of the underwater vehicle 1 and of its velocity vector are not modified by a modification of the orientation of the cable, in the vicinity of the linking element, in this plane P. This configuration makes it possible to avoid the need to provide sophisticated or powerful means or methods for controlling the two vehicles in a coordinated manner or oversized stabilizing means (rudders, thrusters) for stabilizing the underwater vehicle. This solution allows the underwater vehicle 1 to ensure its own stability in the plane P, independently of the surface vessel 100.

The underwater vehicle 1 consumes little energy in order to stabilize itself in the plane P; this stabilization does not make it necessary to compensate the lever arm between the application point of the pulling force F of the cable 3 and the center of inertia G of the vehicle. This configuration makes it possible to use this vehicle both as a towfish and ROV and, if it has the requisite batteries, as a UUV. This makes it possible acquire quality sonar images at high speed.

Furthermore, the position of the center of gravity, in contrast to the center of thrust and to the center of pressure, does not change depending on the speed and the forces brought into play. Thus, the moments generated by gravity and buoyancy are fixed. The stabilizing device, for example the vectorial thruster, does not have to compensate for variations in moments due to a variation in the speed (or has to compensate little therefor).

The proposed configuration runs counter to the tendency of a person skilled in the art, which is, when an underwater vehicle 1 is intended to be towed by a surface vessel 100, to provide an application point of the pulling force F at a distance from the center of inertia G of the vehicle in order that the attitude and the trajectory of this vehicle are set by the trajectory of the surface vessel 100 and by the speed thereof.

Advantageously, but not necessarily, the center of inertia G of the underwater vehicle 1 and its center of buoyancy are situated in the plane P. The submerged underwater vehicle 1 is subjected only to hydrodynamic forces and gravity, the vehicle passes into a balanced configuration in which the axis connecting the center of buoyancy of the underwater vehicle 1 and the center of gravity of the underwater vehicle is vertical, and the plane P is then a vertical plane. The proposed solution thus makes it possible to avoid destabilization of the underwater vehicle 1 in the plane P as a result of a change in relative speed between the underwater vehicle 1 and the surface vessel 100 in the plane P.

Advantageously, the underwater vehicle 1 is intended to move mainly along an axis, known as the main axis x of movement in the patent application, integral with the body 10 of the underwater vehicle 1. This main axis of movement x is advantageously parallel to the plane P or contained in the plane P and perpendicular to the straight line passing through the center of buoyancy and the center of inertia G of the underwater vehicle 1. This solution is particularly suitable for sonar imaging of seabeds which involve long paths of the vehicle along its main axis of movement, in one and the same plane P as the surface vessel (in the absence of current), the surface vessel being at a greater altitude than that of the underwater vehicle with respect to the seabed. The vehicle is then destabilized only during changes of course.

In the examples shown in figures 2 to 5, the underwater vehicle 1 extends longitudinally along the main axis of movement x. In other words, the body 10 of the underwater vehicle 1 extends longitudinally along this axis. A change in direction of the pulling force F in the vertical plane thus has no impact on the longitudinal pitch of the underwater vehicle 1. This configuration allows the underwater vehicle 1 to control its longitudinal pitch during a mission in which the underwater vehicle is used as an ROV or as a towfish. This configuration, makes it easier to keep the underwater vehicle at a predetermined depth or at a predetermined altitude with respect to a seabed even in the event of a change in depth or speed of the surface vehicle.

Advantageously, the linking element 4 is connected to the body 10 of the underwater vehicle 1 by a link 5 having at least one degree of rotational freedom about an axis of rotation y such that the pulling force F exerted by the cable 3 on the underwater vehicle 1 is able to pivot about the axis of rotation y, the projection of the axis of the pulling force F on the plane P being radial to the axis of rotation y. Consequently, when the plane P is vertical under equilibrium, the axis of rotation y is substantially horizontal, as shown in the figures.

Advantageously, the linking element 4 is configured and connected to the body 10 such that when the cable 3 cooperates with the linking element 4, itself connected to the body 10, the projection of the axis of the pulling force F on the plane P passes through the center of inertia G of the vehicle, regardless of the orientation of the pulling force F about the axis y in an angular work sector defining a non-zero angle, that is to say a nonzero opening. In this angular work sector, the cable does not come to bear on the body 10 of the underwater vehicle 1.

Advantageously, the axis of rotation y is connected to the body 10 so as to obtain this effect.

In a first embodiment, examples of which are shown in figures 2 and 3, the axis of rotation y is able to pass through the center of inertia G. It may be able to take up one or more positions with respect to the body 10 of the underwater vehicle 1. In the latter case, the machine may, but does not have to, comprise drive means for moving this axis of rotation y with respect to the body 10.

In the examples shown in figures 2 and 3, the linking element 4 is connected to the body 10 of the underwater vehicle 1 by a link 5 or 65 comprising a pivot link of axis of rotation y, such that when the linking element 4 pivots about the axis of rotation y with respect to the body 10, the pulling force F pivots about the axis of rotation y with respect to the body 10.

In the example in figure 2, the linking element 4 is connected to the body 10 of the underwater vehicle 1 by a link having one degree of freedom. In other words, the link 5 comprises only the pivot link of axis y. The axis of rotation y is fixed with respect to the body 10 of the underwater vehicle 1. It passes through the center of inertia G. The axis of the pulling force F is then radial to the axis of rotation y when the cable 3 is in a plane P perpendicular to the axis of rotation y in the vicinity of the linking element 4.

To this end, the linking element 4 comprises a fork 14 comprising two legs 14a and 14b that are mounted in a pivot link on an arm 15 which is fixed with respect to the body of the vehicle and the longitudinal axis of which is the axis y. The fork 14 comprises a handle 14c. The two legs extend as far as a handle 14c extending longitudinally radially with respect to the axis y. The handle is intended to cooperate with the cable 3 such that the cable 3 passes through the longitudinal axis of the handle 14c.

The arm 15 passes through the body of the vehicle perpendicularly to the axis x and the two legs 14a, 14b each extend next to one of the flanks of the underwater vehicle.

Advantageously, the linking element 4 is configured and connected to the body 10 of the underwater vehicle 1 such that the pulling force F is situated substantially in the plane P when the cable 3 is in a plane perpendicular to the axis of rotation y in the vicinity of the linking element 4. In other words, in figure 2, the handle 14c extends longitudinally in the plane P.

Thus, if the underwater vehicle 1 and the surface vessel 100 navigate in one and the same vertical plane, the axis of the pulling force F passes permanently through the center of inertia G. If the pulling force F leaves this plane, that is to say if the axis I of the cable 3 is inclined with respect to this plane P, the cable 3 generates a rolling moment on the vehicle.

As a variant, the handle 14c extends in a plane parallel to the plane P and at a distance from the plane P or in a plane that is not coincident with the plane P. However, this generates a rolling moment and/or yawing moment on the underwater vehicle, and it is necessary to counter these moments in order that the underwater vehicle maintains its stability.

As a variant, the linking element is connected to the body of the vehicle by a link having more than one degree of rotational freedom. For example, the axis of rotation y is able to pivot, with respect to the body of the underwater vehicle, about the axis x. This makes it possible to limit the rolling moment during a change of course of one of the two vehicles.

The example in figure 3 differs from the one in figure 2 in that the axis of rotation y is able to be moved with respect to the body 10 of the underwater vehicle 1 a of the underwater machine E1.

The underwater machine E1 comprises blocking means comprising for example stops B, making it possible to immobilize the axis of rotation y with respect to the body 10 of the underwater vehicle 1a in a position that can be seen in figure 3, in which the axis of rotation y passes through the center of inertia G. In this position, the axis of rotation y is perpendicular to the plane P. The stops B are movable so as to be able to fix the axis of rotation y with respect to the body 10 in several positions with respect to the body 10. This configuration makes it possible to adjust the position of the axis of rotation y depending on the position of the center of inertia G and thus to be able to obtain the desired stabilization effect for different configurations of the underwater vehicle in which the position of the center of inertia of the underwater vehicle varies. It is possible, for example, to modify the position or number of items of underwater equipment of the underwater vehicle, with an impact on the position of the center of inertia thereof.

In the nonlimiting example in figure 3, the link 65 for connecting the linking element 4 to the body 10 comprises the pivot link 5 and a sliding link 66 of axis x connecting the pivot link 5 to the body 10. This configuration makes it possible to adapt to variations in the position of the center of gravity G along the direction of the sliding link. To this end, the vehicle 1a comprises for example guides GG for guiding the axis of rotation y along the direction of the slide. One guide can be seen in figure 3, the other being situated on the other flank of the vehicle.

In the particular example in figure 3, the direction of the sliding link is that of the main axis x of movement of the vehicle, which is also that of the longitudinal axis x of the vehicle, in which direction the position of the center of inertia will mainly vary when the number of items of equipment in the vehicle is modified.

As a variant, the axis of rotation y is connected to the body 10 of the underwater vehicle 1a by a link having more than one degree of freedom in translational movement, thereby making it possible to obtain greater precision of positioning the axis y in the event of modifications to the position of the center of gravity along another direction than the direction of the axis x.

As a variant, the linking element is connected to the body of the vehicle by a link having more than one degree of rotational freedom. For example, the axis of rotation y is able to pivot, with respect to the body of the underwater vehicle, about the axis x.

As a variant, at the stops, the underwater machine may comprise an actuator for driving the axis y in translation along the axis x along the guides GG. This actuator may comprise a brake for blocking the movement of the axis of rotation y in translation along the axis x.

The blocking means may or may not be contained in the underwater vehicle.

Figures 4 and 5 show a second embodiment of the invention. This embodiment differs from the one in figures 2 and 3 in that the axis of rotation, referenced yo in figures 4 and 5, is at a distance from the center of gravity G of the vehicle. Consequently, the axis of rotation yo is movable with respect to the body 10 of the underwater vehicle 1 b or 1 c.

As can be seen in figure 6, the underwater machine Eb or Ec comprises adjusting means 50 configured to adjust the position of the axis of rotation yo depending on an orientation O of the projection of the axis of the pulling force F on the plane P so as to move this projection such that it passes through the center of gravity G of the underwater vehicle regardless of the direction of the orthogonal projection of the pulling force in the plane P in a predetermined angular sector.

The underwater machine may comprise a sensor 51 for measuring the orientation of the orthogonal projection of the pulling force. This measurement may be taken directly by an angle sensor on the linking element for example or on the cable, or indirectly, for example, by a strain gage.

The adjusting means 50 comprise for example, as shown in figure 6, an actuator A for moving the axis of rotation yo with respect to the body 10 of the underwater vehicle 1b or 1c and control means C that are able to control the actuator A and are configured to control the actuator depending on an orientation O of an orthogonal projection of the axis of the pulling force on the plane P. The orientation O may be the angle a formed between the pulling force F and the axis x in the plane P. The control means are configured to control the actuator so as to move the axis yo in order to move the orthogonal projection of the axis of the pulling force on the plane P such that it passes through the center of gravity G.

As a variant, the adjusting means comprise passive means comprising for example a calibrated spring for ensuring the desired position of the linking element depending on the orientation.

The example in figure 4 differs from the one in figure 3 in that the axis of rotation yo of the link having at least one degree of rotational freedom is at a distance from the center of inertia G. The link 70 connecting the linking element 4b to the body 10 of the vehicle 1b comprises a pivot link 71 of axis yo and a sliding link 72 of axis xo parallel to the axis x, connecting the axis yo to the body of the vehicle. The axis xo belongs advantageously to the plane P. The linking element 4b has the same fork shape as the linking element 4 with two legs 14a’ and 14b’ connected to a handle 14c’ a handle 14c’ extending longitudinally radially with respect to the axis yo. The handle is intended to cooperate with the cable 3 such that the cable 3 passes through the longitudinal axis of the handle 14c’.

The two legs 14a and 14b’ are mounted in a pivot link on a block 73 about a longitudinal arm 74 of longitudinal axis yo. The fork comprises a handle 14c’.

The vehicle 1b comprises a guide GU for guiding the block 73 in translation along an axis xo parallel to the axis x.

Advantageously, as in figure 3, the longitudinal axis of the handle

14c’ belongs to the plane P.

The example in figure 5 differs from the one in figure 4 in that the linking element 4c is connected to the body of the underwater vehicle by a link 80 comprising a cardan joint 81 having to axes of rotation, namely the axis of rotation yo and another axis parallel to the axis x. This makes it possible to avoid pitching of the vehicle during changes of course. The cardan joint is connected to the body of the underwater vehicle by a sliding link 72, as in the case of the pivot link of the embodiment in figure 4. The linking element 4c comprises a loop 85 connected to a block 83 by cardan joint 81. The block 83 is connected to the vehicle by the sliding link 72. The vehicle 1c comprises a guide GU for guiding the block 83 in translation along the axis of the sliding link. The linking element 4c comprises a handle 86 intended to cooperate with the cable such that the axis I is substantially the longitudinal axis of the cable.

The handle 86 extends longitudinally radially with respect to the axis yo. The handle 86 is intended to cooperate with the cable 3 such that the cable 3 passes through the longitudinal axis of the handle 86.

Advantageously, the linking element 4c has a greater angular displacement about the axis of rotation y than about the other axis of rotation of the cardan joint.

Advantageously, the linking element is configured and connected to the body of the vehicle such that the handle 86 is able to pivot either side of the plane P.

In each of the embodiments, the linking element can be connected to the underwater vehicle in a removable manner. As a variant, the linking element is able to be disposed in a stowed position with respect to the body of the underwater vehicle in that it is disposed inside the volume delimited by the body of the underwater vehicle.

The cable can be fastened removably to the linking element or be fastened permanently to the linking element.

The underwater vehicle advantageously comprises attitude adjusting means for varying at least one attitude angle of the underwater vehicle. In one example, the adjusting means make it possible to adjust the pitch of the underwater vehicle. These means allow the vehicle to adjust this attitude angle itself.

These means comprise for example means for varying at least one attitude angle of the vehicle, for example the pitch thereof, and means for controlling the means for varying the attitude angle so as to adjust this attitude angle. These means are for example the control member.

The thruster 2 is for example a vectorial thruster. In other words, the thruster 2 is a vectorial thruster that is able to generate vectorial thrust,

i.e. thrust that is orientable with respect to the body 10 of the underwater vehicle 11. This thruster is an omnidirectional vectorial thruster. It is able to generate thrust that is orientable through 4π steradians. An example of such a thruster is a thruster comprising two counterrotating propellers that each comprise blades 17, the collective and cyclical incidence of which about a neutral position is variable. The thruster 2 therefore makes it possible adjust the three attitude angles of the underwater vehicle. As a variant, the means for varying at least one attitude angle of the vehicle comprise rudders.

The vehicle comprises at least one energy accumulator for accumulating electrical energy and powering electrical equipment of the vehicle, for example the thruster, at least one sensor of the thruster, for example a sonar antenna, the means for adjusting at least one attitude, the possible means for adjusting the position of the axis of rotation, etc. The underwater vehicle 1 can then be used as a towfish, ROV and AUV.

Advantageously, the linking element 4 is provided with an electric interface that electrically connects the cable 3 and the underwater vehicle when the cable 3 cooperates with the linking element 4 so as to allow transmission of electrical energy from the cable to the underwater vehicle 1, for example in order to power the electrical equipment directly or via at least one electrical energy accumulator.

Advantageously, the linking element 4 is provided with a data interface for transmitting data from the cable 3 to the underwater vehicle 1, for example to a sonar antenna or a sonar data memory, and/or vice versa, when the cable 3 cooperates with the linking element 4.

For greater clarity, an overall interface for ensuring the two types of interface is shown only in figures 2 and 3. This overall interface comprises an interface cable connected to the linking element 4 and to the vehicle.

The possibility of using the underwater vehicle as a towfish, ROV and possibly UUV makes it possible to obtain the advantages of the different uses with one and the same vehicle.

The towfish equipped with an SAS requires the use of a sufficiently powerful surface ship for towing the towfish and for launching and recovering it (it therefore has to be equipped with a system for launching and recovering the towfish), such that the speed of the towfish can be relatively rapid (around 10 knots) and the temporal imaging coverage is relatively high. Technically, the high speed makes it necessary to have a long SAS antenna (around 2 m) that is well suited to rapid speeds. The cable makes it possible to send the SAS data in real time to the surface and also makes it possible to power the ROV.

The use of ROVs is generally linked with a low speed imposed by the joint navigation of the machine and of the surface ship. Since the ROV is driven from the ship, the use of this solution often requires surface ships that are able to accommodate the ROV on board and deploy it and recover it as required. Because the ROV is underpowered compared with the surface ship, the operating speed is slow (a few knots) and the SAS antenna by its nature rather short (around 1 m).

The UUV equipped with an SAS has a limited energy reserve, forcing it to navigate slowly in order to optimize the mission time. The area covered by imaging is generally more limited, the higher the speed of the AUV, since propulsion then becomes the dominant factor for consumption of the batteries. Furthermore, this solution requires data processing at the end of the mission since the data are only available when the UUV returns to the surface. However, this solution makes it possible to undertake a mission in complete autonomy and thus without being detected and at great depths.

The invention makes it possible to provide the underwater vehicle with a capacity to operate at high speed as an ROV without destabilization of the vehicle and to allow the analysis of the data therefrom in real time while maintaining its capability of operating at depth.

The underwater vehicle advantageously comprises at least one sensor ANT, depicted only in figure 5 for greater clarity, which is intended to acquire data about an environment of the vehicle, for example at least one sonar antenna and/or at least one image sensor. The vehicle is advantageously equipped with a synthetic aperture sonar comprising an antenna for emitting acoustic waves and at least one linear antenna for receiving acoustic waves. The emitting antenna may be the receiving antenna or a separate antenna. Advantageously, the SAS comprises two antennas for receiving acoustic waves that are disposed on either side of the plane P.

The invention makes it possible to avoid the drag of the cable exerting an excessive reactive force on the underwater vehicle at the linking element and generating navigation instabilities, this being beneficial for the quality of acoustic images obtained by means of an SAS. The vehicle can thus be used at high speed and therefore makes it possible to obtain high temporal coverage (size of the area imaged per unit time) by providing a sufficiently long receiving antenna.

Each member or control means may comprise one or more dedicated electronic circuits or a general use circuit. Each electronic circuit may comprise a reprogrammable calculation machine (a processor or a microcontroller for example) and/or a computer running a program comprising a sequence of instructions and/or a dedicated calculation machine (for example a set of logic gates such as an FPGA, a DSP or an ASIC, or any other hardware module).

In the field of underwater applications, the gravitational constant is presumed to be fixed. The center of inertia of the vehicle is substantially the center of gravity thereof.

Advantageously, the main axis of rotation is substantially perpendicular to the axis of rotation y or yo.

Claims

1. An underwater machine (E) comprising an underwater vehicle (1), the underwater vehicle (1) comprising a body (10) of the underwater vehicle (1), the underwater machine (E) comprising a linking element (4) that is connected to the body (10) of the underwater vehicle (1) and is able to cooperate with a cable to take up a pulling force (F) exerted by the cable (3) on the underwater vehicle (1), the linking element being connected to the body of the vehicle and being configured such that the axis of the pulling force (F) is movable with respect to the body (10) of the vehicle and able to exhibit different orthogonal projections in a fixed plane P with respect to the body (10) that passes through the center of inertia (G) of the underwater vehicle (1), the linking element (4) being connected to the body (10) of the underwater vehicle (1) by a link (5) having at least one degree of rotational freedom about an axis of rotation (y; yo) such that the pulling force (F) exerted by the cable (3) on the underwater vehicle (1) is able to pivot about the axis of rotation (y; yo), the projection of the axis of the pulling force (F) on the plane (P) being radial to the axis of rotation (y; yo), the linking element (4) being configured and connected to the body (10) such that when the cable (3) cooperates with the linking element (4), the projection of the axis of the pulling force (F) on the plane (P) passes through the center of inertia (G) of the underwater vehicle (1) regardless of the orientation of the pulling force (F) about the axis (y; yo) in an angular work sector with a predetermined nonzero opening.

2. The underwater machine (E) as claimed in the preceding claim, wherein the axis of rotation (y) is fixed with respect to the body (10).

3. The underwater machine (E) as claimed in the preceding claim, wherein the linking element is connected to the body of the underwater vehicle by a link having one degree of freedom.

4. The underwater machine (E) as claimed in claim 1, wherein the axis of rotation (yo) is at a distance from the center of inertia (G) of the underwater vehicle (1b, 1c), and wherein the axis of rotation (yo) is movable with respect to the body (10) of the underwater vehicle, the underwater machine comprising adjusting means configured to adjust the position of the axis of rotation (yo) on the basis of an orientation of a projection orthogonal to the axis of the pulling force so as to make the orthogonal projection of the pulling force pass through the center of inertia (G) of the underwater vehicle (1 b, 1 c) regardless of the orientation thereof in the angular sector.

5. The underwater machine (E) as claimed in claim 4, wherein the adjusting means comprise an actuator for moving the axis of rotation (yo) with respect to the body (10) of the underwater vehicle (1b, 1c) and a control member that is able to control the actuator.

6. The underwater machine as claimed in either one of claims 4 and 5, wherein the link having at least one degree of rotational freedom about the axis of rotation is a pivot link.

7. The underwater machine (E) as claimed in either one of claims 4 and 5, wherein the link having at least one degree of rotational freedom about the axis of rotation is a cardan joint having two axes, namely the axis of rotation and another axis of rotation of the plane P.

8. The underwater machine as claimed in the preceding claim, wherein the pulling force has a greater angular displacement about the axis of rotation than about the other axis of rotation.

9. The underwater machine (E) as claimed in any one of the preceding claims, wherein the center of inertia (G) of the underwater vehicle (1) and the center of buoyancy of the underwater vehicle are situated in the plane P.

10. The underwater machine (E) as claimed in any one of the preceding claims, wherein the main axis (x) of movement of the vehicle is parallel to the plane P and perpendicular to a straight line passing through the center of buoyancy and the center of inertia (G) of the underwater vehicle (1).

11. The underwater machine (E) as claimed in any one of the preceding claims, wherein the body (10) of the underwater vehicle (1) extends longitudinally along the main axis of movement (x).

12. The underwater machine as claimed in any one of the preceding claims, wherein the different orthogonal projections of the axis of the pulling force in the plane P are obtained by a movement of the linking element (4) with respect to the body of the underwater vehicle without deformation of the

5 linking element.

13. The underwater machine as claimed in any one of the preceding claims, wherein the underwater vehicle comprises a thruster.

10

14. The underwater machine as claimed in any one of the preceding claims, wherein the thruster is a vectorial thruster.

15. The underwater machine (E) as claimed in the preceding claim, wherein the underwater vehicle (1) comprises attitude adjusting means for

15 adjusting at least one attitude angle of the underwater vehicle.

16. The underwater machine as claimed in the preceding claim, wherein the underwater vehicle (1) comprises an electrical energy accumulator.