TECHNICAL FIELD
The present invention generally relates to the field of aquatic activities and in particular measurements of marine areas and seabed using on-board sensors. More particularly, it relates to a motorised, monohull, autonomous ship, or drone, with a ballasted keel, transformable into a trimaran thanks to a removable anti-roll stabilisation system. It may be applied to any aquatic environment: ocean, sea, lake, river, etc.
TECHNOLOGICAL BACKGROUND
A floating sea vessel with a removable measurement keel is known from FR17 61547. The motorised vessel includes a removable keel, in the bottom part of its hull, and a wheelhouse erected above the deck, in the upper part of its deck. The vessel's keel can be lowered under the hull and lifted up through the hull into a keel storage space of the wheelhouse.
The unusual implementation of a ballasted keel for such a motorised ship is due to the fact that the ship is of the wave-piercing type and tapered, while having an upward wheelhouse. The presence of the ballasted keel allows lowering the ship's centre of gravity when the keel is lowered and allows stabilising the ship at least with respect to heel and the risks of tipping over sideways.
To ensure this stabilisation, the ballasted keel must therefore be lowered down and the ship has then a relatively deep draught of around two metres or more. It results therefrom that the ship cannot sail in shallow waters, unless lifting the ballasted keel up. It therefore results an instability, particularly heel, or even a risk of capsizing/overturning. A solution would be to increase the ballast weight at the lower end of the keel to obtain a sufficient lowering of the centre of gravity whereas the keel is lifted up. However, this is achieved at the expense of the load capacity of the ship, among other drawbacks. Moreover, this may however require that the ballasted keel is not fully lifted up, at the expense of draught reduction.
It is thus desirable to have less restrictive means of stabilising the ship whereas the ballasted keel is lifted up, or even removed in order to allow the ship to sail in very shallow waters.
It will be seen that the invention can also find occasional application in rescue and recovery of a ship that has broken down.
The following documents are also known in this field: FR 3 074 474 A1, U.S. Pat. No. 4,898,113, CN 107 878 669, WO 2014/047639, US 2014/261126 et CN 106 976 527.
DISCLOSURE OF THE INVENTION
It is proposed according to the invention a motorized, wave-piercing, autonomous surface ship with a tapered hull, the hull having a deck, the ship having a wheelhouse erected on said deck, the ship further including, under the hull, a ballasted keel intended to lower the ship's centre of gravity to stabilise the ship at least with respect to the roll, wherein the keel is removable and able to be placed in several positions including a lower position, in which the ship's centre of gravity is lowered, and an upper or extracted position, in which the ship's centre of gravity is raised.
According to the invention, the ship can sail as a monohull or as a trimaran, the hull including a device for removable attachment of an anti-roll stabilisation system intended to counter at least the roll, the anti-roll stabilisation system including an elongated connection arm terminated at its two lateral ends by two floats, the connection arm including an attachment member, the attachment member being configured to be removably attached on the attachment device in order to transform the ship into a trimaran, the two floats being arranged on the port and starboard sides of the hull respectively, and in that the ship is a monohull in the absence of the anti-roll stabilisation system.
Other non-limiting and advantageous features of the ship according to the invention, taken individually or according to all the technically possible combinations, are the following:
- the ship does not comprise a wind propulsion,
- the deck corresponds to the upper level, out of water, in free air, of the ship's hull,
- the ship is an exploration ship,
- the removable ballasted keel is a measurement keel including at least measurement instruments,
- the ship's hull is substantially spindle-shaped with a tapered stem in order to form a wave-piercing ship,
- the deck has an upwardly convex surface,
- the ship has a front end or bow and a rear and or stern,
- the ship's bow tapers into a point,
- the ship's bow tapers into a blade,
- the ship's stern is flat,
- the monohull ship has a total width to total length ratio lower than 0.2 and a maximum length lower than 20 metres, said length and width being respectively considered along the longitudinal direction of the vessel and a horizontal transverse direction, perpendicular to the longitudinal direction,
- the ship has a ratio height above the waterline of the hull, excluding its potential appendices, excluding the wheelhouse, to height under the waterline of the hull, excluding its potential appendices, hence excluding the keel, that is lower than 0.8 and higher than 0.1,
- the ship has a length of at least 2.5 metres and a maximum length of 20 metres,
- when the trimaran is vertical, the two floats are in water,
- the two floats have identical buoyancy,
- the two floats have different buoyancies,
- the connection arm is rigid,
- the connection arm includes at least one joint that can be locked,
- the anti-roll stabilisation system itself can float and is stable with the two floats in water,
- for a connection arm designed to pass under the hull, the anti-roll stabilisation system itself can float and is stable with the two floats in water and the connection arm at least in part underwater,
- for a connection arm designed to pass above the hull, on the deck, the anti-roll stabilisation system itself can float and is stable with the two floats in water and the connection arm out of water,
- the anti-roll stabilisation system itself able to float is able to sail,
- the anti-roll stabilisation system itself able to float and able to sail moves by being towed,
- the anti-roll stabilisation system itself able to float and able to sail moves on its own, the floats having propulsion sets,
- the anti-roll stabilisation system itself able to float and able to sail and having propulsion sets includes a means for steering by differential control the propulsion sets of the two floats,
- the floats include steering devices, in particular rudders,
- the floats include fins,
- the floats have an adjustable buoyancy,
- the floats have ballast means in order to make their buoyancy adjustable,
- the adjustable buoyancy of the floats makes it possible to lift or lower the connection arm or the anti-roll stabilisation system, in particular when it is not attached to the ship,
- the anti-roll stabilisation system itself able to float and able to sail and including propulsion sets is remote-controlled,
- the anti-roll stabilisation system itself able to float and able to sail and including propulsion sets and that is remote-controlled is remote-controlled by wire or radio, or remote-controlled by modulated light beam, possibly combined,
- the anti-roll stabilisation system includes automatisms,
- at least one of the automatisms of the anti-roll stabilisation system allows an automatic docking of the anti-roll stabilisation system on the ship's hull,
- at least one of the automatisms of the anti-roll stabilisation system is an autopilot making it possible to follow a programmed trajectory,
- at least one of the automatisms of the anti-roll stabilisation system is an obstacle-avoidance system that makes it possible to avoid the collisions with any obstacle detected by the perception devices, in particular lidar, cameras, radar, sonar . . .
- the anti-roll stabilisation system includes perception means and sensors,
- the floats of the anti-roll stabilisation system include perception means and sensors,
- the connection arm of the anti-roll stabilisation system includes perception means and sensors,
- the monohull or trimaran ship is drone,
- the monohull or trimaran ship is remote-controlled,
- the remote-controlled monohull or trimaran ship is remote-controlled by wire or radio, or remote-controlled by modulated light beam, possibly combined,
- the monohull or trimaran ship includes automatisms,
- at least one of the automatisms of the ship is an autopilot making it possible to follow a programmed trajectory,
- at least one of the automatisms of the ship is an obstacle-avoidance system that makes it possible to avoid the collisions with any obstacle detected by the perception devices, in particular lidar, cameras, radar, sonar . . .
- at least one of the automatisms of the ship is a mission planner, making it possible to sequentially perform a series of autonomous behaviours, in particular to perform a mission of oceanographic hydrography, underwater acoustic positioning, underwater<->surface communication gateway, any measurements at sea . . .
- the ship and the anti-roll stabilisation system include complementary equipment intended to allow an automated docking of the anti-roll stabilisation system to the ship,
- the ship and the anti-roll stabilisation system include complementary equipment intended to allow an automated separation of the anti-roll stabilisation system from the ship,
- the attachment member and the attachment device include an automated locking-unlocking means controlled by complementary equipment of the ship and the anti-roll stabilisation system, in order to allow an automated docking or an automated separation between the ship and the anti-roll stabilisation system,
- the attachment device is positioned at the front of the wheelhouse,
- the attachment device is positioned at the rear of the wheelhouse,
- the attachment device is positioned on the hull's deck, the connection arm passing above the hull, on the deck,
- for a connection arm passing above the hull, on the deck, the attachment member of the connection arm is positioned on the lower side of the connection arm,
- the attachment device is positioned on at least one of the two hull's lateral sides, the connection arm passing under the hull,
- the attachment device is distributed over the two hull's lateral sides, the connection arm passing under the hull,
- for a connection arm passing under the hull, the attachment member of the connection arm is positioned on the upper side of the connection arm,
- the connection arm is configured to pass above the hull, on the deck,
- the attachment member of the connection arm is located at one place,
- the attachment member of the connection arm is located at several places,
- the attachment member of the connection arm is median and is arranged along the arm at substantially equal distance from the two floats,
- the attachment member of the connection arm is laterally offset with respect to the median point of the connection arm located at equal distance from the two floats and one of the two floats has a higher buoyancy than the other float,
- the attachment member of the connection arm is median and is arranged along the arm at substantially equal distance from the two floats and the two floats have identical buoyancy,
- at least one of the attachment members of the connection arm and of the attachment device is adjustable in height,
- the ship is monohull when the ballasted keel is in lower position and the ship is a trimaran when the ballasted keel is in upper position or extracted,
- the wheelhouse height is of about 1.5 metres, measured from its base on the deck,
- the wheelhouse has an aerodynamic shape,
- the wheelhouse has a ratio height (measured with respect to its base) to width (in the direction transverse to the displacement axis of the ship) higher than 3,
- the wheelhouse includes a keel storage space,
- the keel and the keel storage space of the wheelhouse have aligned main axes that are vertical,
- the keel and the keel storage space of the wheelhouse have aligned main axes that are inclined with respect to the vertical,
- the main axis of the wheelhouse and the main axis of the keel storage space of the wheelhouse are parallel and, preferably, collinear to each other,
- the wheelhouse includes the keel storage space in its lower portion and equipment in its upper portion,
- the hull includes a keel well allowing the lowering and lifting passage of the keel,
- the removable ballasted keel is translatable and may be lowered down under the hull, to the keel lower position, and be lifted up at least partly into the keel storage space of the wheelhouse, to the keel upper position,
- the removable ballasted keel is detachable from the ship, the detached keel being in extracted position,
- the detachable removable ballasted keel is moreover translatable,
- the keel is interchangeable,
- the ship includes a means for locking the keel in lower position,
- the ship includes a means for locking the keel in upper position,
- the anti-roll stabilisation system includes an electric power source and the floats include electric propulsion sets,
- the propulsion sets of the flats include propellers or turbines,
- the motorised ship includes propeller or turbine propulsion sets,
- the ship includes navigation equipment, including a rudder,
- the drone includes remote-controlled and/or pre-programmed computer navigation equipment,
- the removable attachment device and the attachment member include electrical connectors that allow the transmission of at least electrical power between the ship and the anti-roll stabilisation system,
- the removable attachment device and the attachment member include electrical connectors that allow data transmission,
- the ballasted keel includes at its lower end a bulb or a gondola,
- in the ballasted keel, the essential of the ballast is in the bulb,
- the bulb is longitudinally elongated,
- a connection portion of the keel is extended between, upward, the upper end of the keel and, downward, the bulb,
- the keel's connection portion has a constant cross-section over its height,
- the cross-section of the keel's connection portion is circular, ovoid or spindle-shaped,
- the keel's connection portion has a smaller longitudinal extension than the bulb longitudinal extension,
- the maximum width of the keel's connection portion is lower than or equal to the maximum width of the bulb, the maximum length of the connection portion being lower than the bulb maximum length,
- the ratio between the maximum width of the connection portion and the maximum width of the bulb is between 0.05 and 0.5,
- in upper position of the keel, the bulb is raised against the hull,
- in upper position of the keel, the bulb is raised into a recess of the hull, against the hull,
- the bulb includes at least measurement instruments,
- the ship is intended to perform acoustic measurements and it includes acoustic measurement systems including acoustic wave transceiver transducers, and at least the acoustic wave transceiver transducers are arranged in the keel's bulb,
- the ship includes an attitude measurement unit including attitude measurement sensors and at least attitude measurement sensors are arranged in the keel's bulb,
- the ballasted keel includes at least one keel fin,
- the keel fin is removable or retractable,
- the keel fin(s) are positioned towards the lower end of the ballasted keel,
- the keel fin(s) are positioned on the bulb or the gondola,
- the keel fin(s) are movable,
- the movable keel fin(s) are controlled by an attitude control unit of the ship,
- the wheelhouse has a front end direct towards the front end of the ship,
- the wheelhouse has a rear end direct towards the rear end of the ship,
- for a connection arm passing above the hull, on the deck, the connection arm includes at least one notch intended to receive one of the two front or rear ends of the wheelhouse, the notch edges coming against said end of the wheelhouse,
- for a connection arm passing above the hull, on the deck, the assembly of the notched connection arm on the ship provided with a wheelhouse is similar to a straight-tail assembly, wherein the connection arm partly surrounds the wheelhouse,
- the removable attachment device of the hull and the attachment member of the connection arm of the anti-roll stabilisation system are each made of two portions, a front portion and a rear portion,
- the ship includes a lifting chain plate,
- the lifting chain plate is on the deck,
- the lifting chain plate is on the deck, positioned at the rear of the wheelhouse,
- the lifting chain plate is on the deck, positioned at the front of the wheelhouse,
- for a connection arm passing above the hull and by the rear of the ship, the anti-roll stabilisation system includes, at the front of the connection arm, a pin designed to fit into the ship's lifting chain plate, positioned at the rear of the wheelhouse, the lifting chain plate and the pin forming a respective front portion of the two-portion attachment device and attachment member,
- the removable attachment device of the hull includes a straight tail,
- the attachment member of the connection arm of the anti-roll stabilisation system includes an elongated groove,
- for a connection arm passing above the hull and by the rear of the ship, the attachment device includes a straight tail, positioned at the rear of the lifting chain plate, and the attachment member includes an elongated groove positioned on the lower side of the connection arm of the anti-roll stabilisation system, the groove being widen towards the front of the connection arm and narrowed towards the rear of the connection arm, the straight tail and the groove forming a respective rear portion of the two-portion attachment device and attachment member,
- the removable attachment device of the hull and the attachment member of the connection arm of the anti-roll stabilisation system are each made of two portions, a front portion and a rear portion, and for a connection arm passing above the hull and by the rear of the ship, the anti-roll stabilisation system includes, at the front of the connection arm, a pin designed to fit into the lifting chain plate of the ship, positioned on the deck at the rear of the wheelhouse, the lifting chain plate and the pin forming a respective front portion of the two-portion attachment device and attachment member, and the attachment device includes a straight tail, positioned at the rear of the lifting chain plate, and the attachment member includes an elongated groove positioned on the lower side of the connection arm of the anti-roll stabilisation system, the groove being widen towards the front of the connection arm and narrowed towards the rear of the connection arm, the straight tail and the groove forming a respective rear portion of the two-portion attachment device and attachment member,
- for a connection arm passing above the hull, on the deck, the notch intended to receive one of the two front and rear ends of the wheelhouse further comes against lateral portions of the wheelhouse that are adjacent to said wheelhouse end,
- for a connection arm passing above the hull, on the deck, the notch intended to receive one of the two front and rear ends of the wheelhouse allows to better counteract the torsion forces applied on the anti-roll stabilisation system in particular the ones that apply in a horizontal plane,
- for a connection arm passing above the hull, on the deck, the attachment device is partly positioned on or in the wheelhouse,
- for a connection arm passing above the hull, on the deck, the wheelhouse further includes guiding rails for the notched connection arm,
- for a connection arm passing above the hull, on the deck, the notched connection arm and possibly the wheelhouse are configured in such a way that a same anti-roll stabilisation system can come against the front or the rear end of the wheelhouse,
- the notched connection arm passing above the hull, on the deck, passes away from the deck and the attachment device is positioned on or in the wheelhouse only,
- the connection arm is configured to pass above the hull, on the deck, and the attachment device is positioned under the hull's deck, in a recess including a removable deck hatch, the hatch having to be open to allow the attachment of the attachment member of the connection arm to the attachment device,
- the connection arm is configured to pass above the hull by being applied against the hull,
- the connection arm is configured to pass above the hull by being applied against the deck,
- the attachment member and the attachment device implement a bolted attachment,
- the attachment member and the attachment device implement an attachment by a controllable locking-unlocking means,
- the attachment member and the attachment device implement an attachment by a remote-controlled locking-unlocking means,
- the attachment member and the attachment device implement an attachment by a locking-unlocking means that is magnetic for the locking and electromagnetic for the unlocking.
The invention also relates to an anti-roll stabilisation system intended to transform a monohull surface ship into a trimaran.
According to the invention, the anti-roll stabilisation system is removable and includes an elongated connection arm terminated at its two lateral ends by two floats, the connection arm including an attachment member, the attachment member being configured to be removably attached on an attachment device of the monohull surface ship in order to transform the latter into a trimaran.
Other non-limiting and advantageous features of the anti-roll stabilisation system according to the invention, taken individually or according to all the technically possible combinations, are the following:
- the anti-roll stabilisation system includes one or more of the features described for it,
- the anti-roll stabilisation system can float and is stable with the two floats in water,
- the anti-roll stabilisation system is able to sail by moving on its own, the floats having propulsion sets,
- the anti-roll stabilisation system is remote-controlled,
- the anti-roll stabilisation system includes a pin and a groove,
- the pine and the groove of the anti-roll stabilisation system are intended to be respectively attached to a lifting chain plate and to a straight tail of the ship,
- anti-roll stabilisation system wherein the monohull surface ship intended to receive the anti-roll stabilisation system includes a wheelhouse erected on a deck of the ship's hull and the connection arm of the anti-roll stabilisation system, which is intended to pass above the ship's hull by coming against the deck of said ship, includes a notch intended to receive one of the front or rear ends of the wheelhouse, the notch edges being intended to come against one of the two front or rear ends of the wheelhouse.
The invention finally relates to a kit for transforming into a trimaran a motorized, tapered-hull, wave-piercing, autonomous monohull surface ship, the hull having a deck, the ship having a wheelhouse erected on said deck, the ship further including, under the hull, a ballasted keel intended to lower the ship's centre of gravity to stabilise the ship at least with respect to the roll, wherein the keel can be removable and can be placed in several positions including a lower position, in which the ship's centre of gravity is lowered, and an upper or extracted position, in which the ship's centre of gravity is raised.
According to the invention, in an embodiment in which the monohull ship includes a device for removable attachment of an anti-roll stabilisation system, the kit includes an anti-roll stabilisation system including an elongated connection arm terminated at its two lateral ends by two floats, the connection arm including an attachment member, the attachment member being configured to be removably attached on the attachment device in order to transform the ship into a trimaran, the two floats being arranged on the port and starboard sides of the hull respectively.
According to the invention, in an embodiment in which the monohull does not include a device for removable attachment of an anti-roll stabilisation system, the connection arm including an attachment member that can be attached to a belt for hull intended to come and tightly surround the hull, the kit then includes an anti-roll stabilisation system and at least one hull belt, the anti-roll stabilisation system including an elongated connection arm terminated at its two lateral ends by two floats, the connection arm including an attachment member, said at least one hull belt including a device for removable attachment to the attachment member, said at least one hull belt being configured to be tightened about the hull, the attachment member being configured to be removably attached on the attachment device in order to transform the ship into a trimaran, the two floats being arranged on the port and starboard sides of the hull respectively.
In a particular implementation mode, wherein the monohull ship does not include a device for removable attachment of an anti-roll stabilisation system, the kit further includes at least one belt for wheelhouse configured to be tightened about the wheelhouse and able to be removably attached to the connection arm of the anti-roll stabilisation system.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 shows a front perspective of the ship in the monohull configuration, with its ballasted keel in lower position, the anti-roll stabilisation system being shown in isolation, remote from the rear of the ship,
FIG. 2 shows a front perspective view of the ship in the monohull configuration, with its ballasted keel in lower position, the anti-roll stabilisation system being in the process of being installed on the ship (or, conversely, uninstalled if the anti-roll stabilisation system can be removed from the ship), the anti-roll stabilisation system boarding the ship by the rear of said ship,
FIG. 3 shows a front perspective view of the ship in the trimaran configuration, with its ballasted keel being able to be lifted up, the anti-roll stabilisation system being attached to the ship,
FIG. 4 shows a rear perspective view of the ship in the trimaran configuration, with its ballasted keel being able to be lifted up, the anti-roll stabilisation system being attached to the ship,
FIG. 5 is a side perspective view of the ship in the trimaran configuration, the anti-roll stabilisation system being shown in cutaway view to visualize the relations between the hull's removable attachment device and the attachment member of the connection arm of the anti-roll stabilisation system, which are each made of two portions, a front portion towards the front of the attachment arm and a rear portion towards the rear of the attachment arm, an inset showing an enlarged view of the rear portion, and
FIG. 6 is a bottom view of the anti-roll stabilisation system allowing the visualisation of the elongated groove intended to cooperate with the straight tail of the ship's hull deck.
DETAILED DESCRIPTION OF AN EXEMPLARY EMBODIMENT
The following description in relation with the appended drawings, given by way of non-limiting examples, will allow a good understanding of what the invention consists of and of how it can be implemented.
In its principle, the present invention relates to the field of navigation and underwater exploration by a motorized, wave-piercing, monohull surface ship including a removable/retractable ballasted keel and a wheelhouse, wherein the keel can be lifted or lowered. Such a ship has been described in the patent application FR17 61547 to which reference can be made if desired. The invention allows the use of the ship in very shallow waters, typically waters of less than four meters deep. The invention allows stabilizing the ship whereas the ballasted keel is lifted up/retracted whereas the ship without implementation of the invention risks capsizing as a result of the rising of the keel and this of its centre of gravity.
Thanks to the invention, the monohull ship can be transformed into a trimaran by addition of an anti-roll stabilisation system including two floats and a connecting arm connecting these latter. These floats ensuring the transverse buoyancy of the ship, it is then possible to sail with the keel in lifted/retracted position. Preferably, an electric propeller is added to each float and a rechargeable electric battery+electric converter pack takes place in the floats and the connection arm. It may be noted that the increase of the ship weight due to the addition of the anti-roll stabilisation system may be compensated by an increase of the buoyancy volume provided by the floats themselves.
The invention may take the form of a kit whose elements are attached to the ship's hull in a structure provided for that purpose. When the anti-roll stabilisation system of the kit includes floats with propulsion means, the propulsion system of the anti-roll stabilisation system can be connected to the ship's management system, which then takes control of the propulsion of the floats. The rechargeable electric battery of the anti-roll stabilisation system can be recharged by an electric generator of the ship, typically from the alternator of the ship's main motor.
The propelled anti-roll stabilisation system of the kit may be fitted with communication means and automatisms enabling it to be itself a remote-controlled vessel. The propelled and remote-controlled anti-roll stabilisation system of the kit may be capable of approaching the ship on its own, typically by the rear, and to attach and to connect, autonomously, both mechanically and electrically, to the ship, which allows the ship to continue its mission with the ballasted keel lifted up to the upper position.
It is to be noted that the implementation of the remote-controlled, motorized kit, able to be automatically attached and connected, can also ensure another function than that consisting in allowing the ship transformed into a trimaran to sail with the keel in upper position: it provides the possibility of emergency recovery of a ship that has broken down. Indeed, one of the difficulties of the autonomous vessels is that, in case of breakdown, they require deployment of recovery means that generate costs and/or that prevent the mother ship to continue its mission. The propelled anti-roll stabilisation system of the kit, which thus becomes an emergency recovery kit, may be launched from the coast, from the mother ship or even from another ship already transformed into a trimaran, from which the propelled anti-roll stabilisation system is retrieved after the ballasted keel thereof has been lowered to restore its stability.
As shown in FIG. 1, the ship 10 includes a hull 11 with a deck 19 and is monohull. The ship 10 is motorised with a propeller thruster 15 and means for sailing using a rudder 16 including two lateral fins 17 in its lower portion.
The ship is an unmanned, autonomous floating/surface drone, which a very narrow wave-piercing spindle-shaped hull. The drone is remote-controlled and/or preprogrammed and/or fully autonomous according to its degree of autonomy. The drone is thus mechanically propelled and at least one electric motor or internal combustion engine or chemical reaction engine or even a mixed engine is used, which operates the propeller or, in alternatives, several propellers or one or several turbines.
The ship includes a wheelhouse 14 erected on the deck 19 but has no sails, masts, rigging or other equipment designed to harness the force of the wind to directly propel it.
If considering the hull 11, 19 and the wheelhouse 14 of the ship alone, the overall centre of gravity is rather high, resulting in a considerable transverse instability and an increased tendency to heel. A keel 12, 13, ballasted at its lower end, is thus implemented towards the bottom of the hull 11, at the lower portion of the bottom, in order to lower the centre of gravity of the ship 10 considered in its entirety when the keel 12, 13 is lowered down.
This keel has a bulb 13 or a gondola at its lower end. The bulb 13 is connected to the hull 11 by a connection portion 12 of the keel. The bulb keel includes, preferably in the bulb 13, a ballast intended to reinforce the transverse stability of the ship 10. This ballast is a specific heavy material, for example lead or uranium, and/or corresponds to pieces of equipment, in particular for measurement, installed in the bulb.
Advantageously, the measurement pieces of equipment, in particular acoustic wave transceiver transducer of the SONAR type, and an attitude unit are arranged in the keel's bulb. The bulb may also include a housing for an underwater vessel with propeller set and navigation means, which is able to leave from and to come back into the bulb. It is thus possible to obtain accurate corrections of the acoustic measurements due to the fact that the attitude unit is positioned as close as possible to the acoustic transducers.
The ship 10 has a total length less than 20 metres and a minimum length of at least 2.5 metres. The ship has a total width to total length ratio lower than 0.2. The ship of the drone type shown in the figures has a length between 2.5 m and 6 m.
Thanks to the very narrow shape of the hull 11, the ship 10 has a very low resistance to forward movement in both calm and rough water, given its length. The hull 11 is capable of exceeding the limit hull speed with very little energy and is able to pass into overspeed without yet having a “gliding” shape.
This shape of the hull 11 and the remoteness of the keel's bulb or gondola 13 with respect to the hull 11 further allow improving the flows in the vicinity of the acoustic transducers and avoids the formation of bubbles having a masking effect at the acoustic transducers. It results therefrom a reduction of the “noises” that, in the conventional ships, interfere with acoustic measurements.
The keel 12, 13 is able to be removed/raised and can thus be lowered down and lifted up and even, in certain implementation modes, dismounted relatively simply to be exchanged with another keel. When the keel is lifted up, the upper end of the keel passes into a keel storage space located inside the wheelhouse 14.
In FIG. 1, the keel is lowered down. In this example, the keel 12, 13 may be lowered down until providing to the ship 10 with a draught of two metres deep.
Still in FIG. 1, on the rear of the ship and separated from the ship 10, is shown the anti-roll stabilisation system 1 intended to transform the ship 10 into a trimaran 20. This anti-roll stabilisation system 1 is of the type provided with an upward, out-of-water, connection arm 3. The connection arm 3 includes at its two lateral ends two floats 2 that include propulsion sets 5.
In the example shown, the removable attachment device of the hull, and the attachment member of the connection arm of the anti-roll stabilisation system, are each made of two portions, a front portion and a rear portion, in relation with the orientation of the front and rear ends of the ship.
Thus, as regards the removable attachment device, the latter includes a front portion that is a lifting chain plate 21 positioned on the deck 19 of the hull 11, on the rear of the wheelhouse 14. Still regarding the removable attachment device, the latter includes a rear portion that is a straight tail 22 positioned on the deck 19 of the hull 11, on the rear of the lifting chain plate 21. The straight tail 22 has a general mushroom shape with, towards the top, an enlarged head and, towards the bottom, a foot that is narrower than the head.
To the lifting chain plate 21 of the ship corresponds a pine of the anti-roll stabilisation system that is the front portion of the attachment member of the connection arm 3, the pine being attached to the lifting chain plate when the anti-roll stabilisation system is installed on the ship. To the straight tail 22 of the ship corresponds an elongated groove 6 arranged longitudinally (in relation with the front and rear ends of the ship) in the middle of the lower side of the connection arm 3 of the anti-roll stabilisation system (FIG. 6) and that serves both for the guiding of the anti-roll stabilisation system during its installation and for its holding/attachment once the system installed, the groove corresponding to the rear portion of the attachment member of the connection arm 3.
In order to reinforce the attachment resistance of the anti-roll stabilisation system to the ship, in particular to the forces tending to cause a rotation of the anti-roll stabilisation system in a horizontal plane, a connection arm 3 with a notch 4 allowing the connection arm 3 to bear against lateral sides of the wheelhouse 14 is implemented.
FIG. 2, the anti-roll stabilisation system 1, whose connection arm 3 is configured to pass above the hull 11 of the ship 10, is being installed and boards the ship by the rear of the latter. For that purpose, the anti-roll stabilisation system 1 boarded the ship by the rear, the connection arm passing above the deck and the two propelled floats passing on the port and starboard sides of the ship, respectively. The anti-roll stabilisation system 1 is thus attached on the rear of the wheelhouse 14.
It can be noted that, on this FIG. 2, an anti-roll stabilisation system 1 has been shown, which includes two propulsion sets 5 per float 2, one on the front and one on the rear, to show the possibility of having several propulsion sets per float. The propulsion sets 5 are preferably steerable, as the anti-roll stabilisation system has no rudder on the floats.
In FIG. 3, the ship has been transformed into a trimaran 20 and the ballasted keel can be lifted up, the bulb or the gondola 13 remaining under the hull 11, the major portion of the keel's connection portion 12 height being able to slide into a keel well of the hull and the keel's upper end being able to enter a keel storage space located inside the wheelhouse 14. In certain embodiments, the keel is dismountable and/or the bulb 13 is dismountable and interchangeable, which allows the ship to be used with different configurations of acoustic transducers of various bulbs.
In FIGS. 3 and 4, the anti-roll stabilisation system 1 of the upward, out-of-water, connection arm 3 type, has been attached to the deck 19 of the ship's hull 11, with the hull's attachment device removably attached to the connection arm's attachment member. Attachment of the connection arm to the hull can be made manually by bolting but, advantageously, an automatic locking-unlocking/attachment means is implemented between the attachment device and the attachment member.
In an alternative not shown, the attachment device of the hull, which is on the deck, is hatch covered in the absence of the anti-roll stabilisation system, and the hatch can be removed during installation of the anti-roll stabilisation system. In an implementation mode, the hatch can be sliding or swivelling by remaining secured to the ship.
In FIG. 5, the relations between the ship's elements and the anti-roll stabilisation system attached to the ship's deck 19, on the rear and against the wheelhouse 14, are better seen. In particular, towards the rear of the connection arm, the elongated groove 6 of the connection arm has been slid onto the straight tail 22 of the ship. In FIG. 6, can be better seen the shape of the groove 6 that is wider on the front, on the notch 4 side, than on the rear of the connection arm 3, in order to also form a guiding and positioning means for the anti-roll stabilisation system on the deck of the ship's hull.
The anti-roll stabilisation system is preferably remote-controlled but it can further include automation devices, in particular for installation (transformation of the ship into a trimaran) and removal (ship going back to monohull configuration) of the anti-roll stabilisation system on/from the ship. Moreover, the keel lifting commands can be conditioned to the presence of the anti-roll stabilisation system attached to the ship.
The anti-roll stabilisation system 1 of the invention can also find occasional application in rescue and recovery of a ship that has broken down, and floats, even if the anti-roll stabilisation system is not attached to the ship.
Other means are provided for attaching the anti-roll stabilisation system to the ship in such rescue and recovery conditions and, for example, in the case of a ship with a steel hull, the anti-roll stabilisation system includes magnetic means, preferably electromagnetic for easy removal, making it possible to magnetically “stick” the anti-roll stabilisation system to the hull.
The anti-roll stabilisation system is preferably remote-controlled but it can moreover include automation devices in particular for rescue and recovery.
It is to be noted that the strap-type removable attachment means, able to surround the hull like a lasso or a snare can also be used when the ship floating normally, with the wheelhouse upward, is transformed into a trimaran. These lasso straps or a snare are then functionally similar to the belt for hull.
In other implementation modes, the remote-controlled and motorized anti-roll stabilisation system can be provided with perception means and sensors and be itself an autonomous surface vessel capable, without the ship, to perform missions in very shallow waters.
Patent Application
20240092463
