Method and system of governing a boat or the like

Description

FIELD OF THE INVENTION

The present invention relates to a method and a system for governing a vessel.

BACKGROUND OF THE INVENTION

In the present description and in the claims, the term vessel is to be understood in a broad sense and includes any type of floating vehicle that can be governed according to the characteristics of the method and of the system object of the present description.

In the state of the art, governing systems of vessels are known that are provided with only two engines at the stern of the vessel, such engines allowing the adjustment of the number of revolutions and of the condition of forward gear, reverse gear and neutral in an independent way between them. In combination are also known systems of directional control of the vessel that can be constituted by engines that allow to orient, around a substantially vertical steering axis or having a directional component prevailing in vertical direction, the axis of rotation of the propeller that is substantially horizontal or presents a directional component prevailing in transversal direction to said steering axis, thus orienting the direction of thrust generated by the engine in directions having any angulation with respect to the longitudinal axis of the vessel itself. Said engines are of the type denominated outboard and are fixed to the stern of the vessel by means of a support on which they are pivoted in a rotatable way at least around said substantially vertical steering axis, or are of the type denominated inboard-outboard in which a part of the engine is internal and fixed to the vessel and commands a transmission of actuation of a propeller that is carried by a leg positioned outside the vessel and present an actuation axis of the propeller orientable around a steering axis analogously to what defined above for said axes.

In these governing systems, besides the independent setting of the number of revolutions and/or of the travel direction and of the condition of neutral of the engines, it is also possible to operate a different steering for each engine or for each rudder blade. Thanks to the combination of pre-established angles of steering of the engines and/or of the blades of the rudders and of the number of revolutions of the same, as well as to the travel direction set for each engine or to the condition of neutral of the engines, it is possible to generate combinations of forces on the dynamic center of the vessel that, adding and subtracting at least in part among them, allow to make the vessel itself move along different trajectories with respect to the longitudinal axis of the vessel, such as: moving forward or backward parallel to the longitudinal axis of the vessel, transversal translation along a direction perpendicular with respect to the longitudinal axis of the vessel or along a direction having a pre-established angulation with respect to said longitudinal axis, that is a direction with at least a perpendicular component to said longitudinal axis and a parallel component to said longitudinal axis, an advancement forward or backward along a curved trajectory, that is that combines a variation of orientation of the longitudinal axis of the vessel with a translation in direction of said longitudinal axis and a rotation of said vessel around said dynamic center of application of the propulsion forces, without the vessel executing translations in any direction.

Document U.S. Pat. No. 3,976,023 describes an apparatus for maneuvering a vessel that allows to perform, in a vessel provided with two propulsion groups or means of type Z, the control of the direction of the flow of fluid generated by the propeller, the independent control between them of the speed of rotation of the engines and the neutral setting independent for the two engines as well as the change of forward and reverse gear. The command takes place by means of a single handle or lever with functions entirely assimilable to those of a joystick and that is provided in the command station. Said lever is coupled to a transmitter suitable to emit electric signals in conformity with the movement of the lever to generate various actions of control of the settings of the directional members and/or of the number of revolutions of the engines and/or of the condition of forward gear, reverse gear or neutral of the engines, individually or in combination among them in such a way, that it is possible to maneuver the vessel according to a plurality of maneuvering schemes thanks to said single lever.

Document EP0358686 also describes a system of steering and maneuvering for vessels provided with two propulsion units steerable individually and arranged in the stern part of the vessel as well as distanced transversally from each other with respect to the longitudinal axis of the vessel. These propulsion units can be of any type such as jet engines, outboard engines steerable independently from each other, inboard-outboard engines each with at least a leg provided outside and steerable independently, or propeller units with fixed transmission shaft and separate rudder. The system of steering and maneuvering comprises a selector of functions with the help of which the system can be switched between a normal steering mode, in which the propulsion units are kept substantially parallel during the steering, and at least one special maneuvering mode, in which the steering command is disconnected from the normal governing function and is set automatically, independently from the position of the governing command, with the two propulsion units at symmetric steering angles and in directions opposite to each other, so that the two propulsion units can generate a propulsion force with a resultant component that is directed substantially transversally to the longitudinal axis of the vessel and/or alternatively or in combination a turning movement of the vessel, while the two propulsion units are commanded so as to set opposite forward/reverse propulsive directions to each other. Through the automatic setting of the angular positions of the propulsion units in the special maneuvering mode, the helmsman can concentrate on relatively simple control functions, such as increasing or decreasing the speed of a turn or of the transversal movement, with the help of the control of the number of revolutions of the engine or of the power of the jet of fluid when it is jet engines. It has been found that such maneuvers can be executed in an extremely simple way, but at the same time exact and efficient, and since the normal navigation takes place in conventional way with the aid of the governing and power commands, the helmsman can quickly learn to master the governing system in conformity with the invention. Besides modes of forward and backward advancement, the special maneuvering modes can comprise a mode of transversal movement and a mode of turning.

In the special maneuvering modes of turning or transversal movement of the vessel, the steering command is preferably used to adjust the turning angle of the propulsion units in such a way that the turning angles are modified symmetrically in opposite direction while maintaining the symmetry, so that the point of attack of the resultant force is moved along the longitudinal axis of the vessel or along a prolongation of this axis beyond the bow or the stern of the vessel. In the mode of transversal translation, the helmsman can then easily obtain either a compensating force of external forces acting on the hull such as those generated by the wind and/or by the current, or can combine the transversal translation with a turning movement. In the mode of rotation of the vessel, the displacement of the point of attack of the resultant of the forces generates an increase or a weakening of the torque. Also in this document is provided a table of the settings of the maneuvering commands such as steering angle of the engines or of the rudder, forward or reverse direction of the engines, condition of neutral of the engines, setting of the power, that is of the number of revolutions of the propeller of the engines, of the movement that the vessel executes thanks to the resultant of the propulsion forces acting on the same.

As it appears evident, in order to be able to cover all the modes of displacement of the vessel both with reference to the normal governing operations during the cruise and with reference to special displacement modes such as those provided for example for docking maneuvers or similar, the state of the art provides the presence of at least two engines that are commandable independently from each other and of at least two directional members each respectively for an engine or of steerable engines or of jet engines with orientable jets.

As already highlighted with reference to the prior art, especially the transversal translations are useful in mooring maneuvers and/or in counteracting drift generated by currents and/or by the wind or by other external agents and in maintaining the orientation and the position of the vessel in the absence of an anchoring.

The maneuvering modalities may also provide for simple rotations of the vessel around a vertical axis in the absence of translation, that is around a vertical axis passing through a stationary point, or combinations of roto-translational displacements, in which a translation according to a predetermined direction having a predetermined angle with respect to the longitudinal axis, that is antero-posterior, central of the vessel, is combined with a rotation around a vertical axis of the vessel itself, whereby the orientation of the central longitudinal axis of the vessel may be modified with respect to the set translation direction.

FIG. 1 shows a table of possible steering positions and, in combination, possible forward gear, reverse gear and neutral settings of two steerable engines, such as two outboard engines, two inboard-outboard engines, and the resulting movements of the vessel. With CF is indicated the center of application of the resultant forces from the propulsive flows generated by the two engines in the different steering positions. The arrows FM indicate the direction of said flows of each engine and the arrows FR show the resultant force.

In the NORMAL governing mode the vessel is governed and maneuvered in a conventional way, the steering command operates in such a way that the propulsion units are kept parallel during the turn, while the propulsion power and the direction of the respective propulsion unit may be set individually with the aid of the power command levers. This governing mode is generally used for forward displacements, backward displacements or for simple maneuvers. The steering commands of setting the gear direction and/or of adjusting the number of revolutions of the propellers may be imparted either by traditional command members consisting of control levers provided for each of said settings or said members may be unified in a single command member such as, for example, a joystick or similar.

For relatively complicated maneuvers such as those necessary in harbors, for mooring at the quay or the pier or for maintaining a position both in anchored condition to the seabed and in a condition not anchored to the seabed, a turning mode or a transversal drift mode is selected. In these special maneuvering modes the parallel ratio of the propulsion units caused by the steering command is deactivated and the two propulsion engines are oriented independently of each other in steering directions with different steering angles for the two engines. These steering angles may also be steering angles symmetrical with respect to the longitudinal axis of the vessel and also such that the extensions of the axes of the propellers or the directions of the propulsion flows intersect inside the hull of the vessel or outside said hull. When the steering angles of the two engines or of the two rudders are asymmetrical with respect to the longitudinal axis of the hull, the point of intersection of said extensions is eccentric with respect to said central longitudinal axis of the hull.

In these special maneuvering modes the propulsion engines may both be commanded in forward gear direction or in reverse gear direction or one engine is set to forward gear and the other to reverse gear and/or in neutral condition, and optionally the number of revolutions may be identical or different for the two engines.

In the “ROTATION” mode, both propulsion units are directed towards a point coinciding with the central longitudinal axis of the vessel and/or on an extension in particular beyond the stern of the vessel. When the steering command is set to the neutral position (B and H in the figure), these turning angles are predetermined by a routine previously programmed of the control program of the engines executed by a control unit. Depending on the forward and reverse gear direction set for the two engines, a left turn (position B) or a right turn (position H) of the vessel is obtained. In this mode, it is possible to adjust the steering angles of the propulsion units and therefore shift the point of action with the aid of the steering command, as shown in positions A, C, G and I and/or with the adjustment of the power, that is of the number of revolutions set for each engine.

In the transversal translation mode, so-called “sideway”, both propulsion units are directed towards the barycenter of the vessel CF or a predetermined point of application of the forces acting on the hull of the vessel and the steering command is set in the neutral position (positions E and K). In this case the vessel will move exclusively transversally towards port side or towards starboard side, according to a motion direction not parallel to the direction of the longitudinal axis of the vessel and in particular according to a direction perpendicular to said longitudinal axis. In the presence of wind and/or current causing a torque on the vessel, it is possible to apply a compensating torque by correspondingly adjusting the steering command, the point of action of the resultant force being shifted forward or backward as shown by D, F, J and L in FIG. 1.

Especially in the governing modes related to special maneuvers, such as those described above and in particular for rotations and for transversal translations in directions not coinciding with the directional orientation of the longitudinal axis of the vessel, the use of two engines generates resultant forces and therefore displacements of the vessel comprising components not aligned with the desired directions, whereby the vessel follows trajectories not precise with respect to those desired.

Furthermore, the mass of the vessel is affected by a certain inertia of motion and in the initial phases of a displacement at the application of the propulsion thrust impulses, the inertia of motion causes a delay in the displacement of the vessel with respect to the instant of application of said propulsion impulses. In the absence of external forces such as wind, currents or the like acting on the vessel, this delay depends on the mass of the vessel and also on the hydrodynamics of the hull underwater portion. Furthermore, it is known that in the absence of movement, the vessel is not governable, since the dynamic responses of the hull and of the steering members are activated only when the hull and said members interact with a fluid flow. The inertia of motion of a vessel also has a delay effect when, for example, one wants to stop or reverse a movement of the hull either of translational type or of rotational type or a combination of these two types of movements. The inertia effects therefore cause a delay between the instant of activation of one or both engines and of the bow-thruster or of the stern-thruster and/or of a modification of the operating conditions of one or both engines and of the bow-thruster or of the stern-thruster and the effective displacement of the vessel resulting from said activation and/or modification of the operating conditions. During this period, the vessel is not governed, that is it does not perform controlled displacements, when there is a departure from a stationary condition or it continues the displacement due to control signals generated at a previous instant.

In the governing during the execution of maneuvers, such as mooring, docking and other similar types of maneuvers, the rapidity of response of the vessel with respect to the instant of application of propulsion impulses is critical in order to have greater safety and precision in the displacements of the vessel with respect to obstacles or stationary references provided in the maneuvering area.

SUMMARY OF THE INVENTION

The present invention aims to realize a governing method and system for vessels which allows overcoming the limits of the current methods making possible the execution of special maneuvering movements, such as for example the transversal translation and/or the rotation.

The invention achieves the above-mentioned aims with a method of governing of a vessel comprising at least one bow-thruster and/or at least one stern-thruster which is/are provided respectively at the bow area and at the stern area of the vessel and two engines steerable independently from each other, which method provides for the execution of displacements of the vessel the activation of the bow-thruster and/or of the stern-thruster with a predetermined number of revolutions and a predetermined direction of rotation of the propeller, that is a predetermined direction of the flow generated by said bow-thruster and/or by said stern-thruster and alternatively or in combination the activation of said engines with a predetermined number of revolutions and a predetermined setting of forward gear or reverse gear for each of said two engines, while said engines are steered each independently from the other in a steering direction with respect to the longitudinal axis of the vessel and with a predetermined steering angle,

• • said method providing for the generation of command signals for the alternative or combined activation of said bow-thruster and/or said stern-thruster and/or of one or both said engines with predetermined specific operating conditions thereof or the variation of the operating conditions set with a previous command, alternatively or in combination, of said bow-thruster and/or of said stern-thruster and/or of one or both said engines, said commands providing:
  • a command of said bow-thruster and/or of said stern-thruster relative to the activation of a deviation flow in a predetermined direction or to the modification of the direction of said deviation flow, that is to the activation of the rotation of the propeller of said bow-thruster and/or of said stern-thruster with a predetermined rotation direction or to the modification of said rotation direction of the propeller between a first and a second direction and alternatively or in combination with a command of setting of the thrust intensity exerted by said deviation flow of said bow-thruster and/or of said stern-thruster, that is of setting of a predetermined number of revolutions of said propeller of said bow-thruster and/or of said stern-thruster or a command of variation of said thrust intensity exerted by said deviation flow, that is the variation of said number of revolutions of the propeller of said bow-thruster and/or of said stern-thruster between a predetermined minimum value and a predetermined maximum value of said thrust intensity, that is of said number of revolutions of the engine;
  • alternatively or in combination, a command of activation of at least one or both said engines with a predetermined steering angle of said engine or of each of said two engines and/or with a predetermined direction of the propulsion flow generated by said engine or by said engines, that is with a predetermined direction of rotation of the propeller of said one or more engines and, alternatively or in combination with a command of setting of a predetermined thrust intensity of the propulsion flow of one or both said engines, that is with a predetermined number of revolutions of the engine, that is of the propeller of one or both said engines, or a command of modification of the steering angle of at least one or both engines, that is of the direction of the propulsion flow generated by a corresponding engine, alternatively or in combination with a command of variation of the direction of the propulsion flow generated by one or both said engines, that is of the variation of the rotation direction of the propeller of one or both said engines and, alternatively or in combination, with a command of variation of the thrust intensity of the propulsion flow generated by one or both said engines, that is of the variation of the number of revolutions of one or both engines and therefore of the propeller of one or both engines between a minimum value and a maximum value of said number of revolutions;
  • the steering angles of said two engines being variable and being settable to identical or different values from each other according to concordant or opposite directions and said angles being settable to values corresponding to an orientation of the two engines symmetrical or asymmetrical with respect to the central longitudinal axis of the vessel and the direction of the propulsion flow or the absence of said flow corresponding to a forward gear or reverse gear direction and to a neutral condition of a corresponding engine of said two engines being settable identical or different between them for said two engines;
  • and which method provides for an initial temporally limited phase of automatic increment or of automatic decrement of one or more of the operating conditions of the bow-thruster and/or of the stern-thruster and/or of one or both said engines defined with one or more of said activation commands and/or of modification or variation of said operating conditions, at the end of which temporary initial phase the operating conditions defined by said one or more commands are restored.

In one embodiment, the duration of said temporary initial phase and/or the increment or the decrement of the operating conditions of the bow-thruster and/or of the stern-thruster and/or of one or both propulsion engines with respect to those defined by said command or by the combination of commands is defined as a function of the contingent navigation conditions of the vessel and/or as a function of the mass thereof, that is of the inertia of motion deriving from said mass.

In one embodiment, the duration of the temporary initial phase of application of said command or of a combination of said commands and/or the increment or the decrement of the operating conditions set and defined by said command or by the combination of said commands is determined empirically by application of one or of a combination of said commands by means of manual setting members of a target displacement of the vessel which are univocally correlated with one or with a combination of said commands and verification of delays or differences of execution of the actual displacement of the vessel with respect to that defined by said at least one command or by said combination of commands, operating manual variations or compensating corrections of the operating conditions defined by said command or by said combination of commands and applying said variations or manual corrections for a predetermined period of time by means of said setting members, said variations and/or corrections and/or said predetermined period of time being stored and used as determination of the duration of the temporary initial phase at the moment of the application of said command or of said combination of commands and for the determination of the increment of one or more of the operating conditions defined in one or in a combination of commands and applied automatically in said temporary initial phase.

The presence of bow-thruster and/or stern-thruster in vessels is increasingly frequent also for small-sized or reduced-tonnage vessels. These devices require a through channel, in particular a transversal channel provided in the underwater portion of the vessel and therefore they are already provided at the production of the vessel. Less widespread are installations of bow-thruster or stern-thruster in retrofitting since the intervention on the underwater portion of the hull is not always welcomed. There also exist bow-thruster or stern-thruster applicable respectively at the bow or at the stern of the vessel and which present a structure similar to that of outboard engines. Such devices are, however, not very widespread.

In one embodiment of the present invention, the method provides the generation of setting commands of a target displacement, that is desired displacement, of the vessel by means of setting members which generate setting signals which are processed by a control unit to generate at least one control signal and/or a combination of control signals of actuators associated to the bow-thruster and/or to the stern-thruster and respectively to each of said two engines,

• • said actuators being configured to modify respectively one of the operating conditions of the bow-thruster and/or of the stern-thruster and/or of one or both engines respectively relative to the direction of the deviation flow and/or to the thrust intensity of said deviation flow, that is to the direction of rotation of the propellers and/or to the number of revolutions of the engine or of the propeller for the bow-thruster and/or the stern-thruster and relative to the direction of the deviation flow and/or to the thrust intensity of said deviation flow, that is to the direction of rotation of the propellers and/or to the number of revolutions of the engine or of the propeller and to the steering angle for one or both said engines;
  • said control signals comprising the setting values respectively of:
  • the direction of the deviation flow, that is of the rotation of the propellers and/or of the thrust intensity exerted by said flow, that is of the number of revolutions of the engine or of the propellers of the bow-thruster and/or of the stern-thruster;
  • the direction of the deviation flow, that is of the rotation of the propellers and/or of the thrust intensity exerted by said flow, that is of the number of revolutions of the engine or of the propellers of one or of both propulsion engines;
  • the steering angle of one or of both engines;
  • the method providing in said temporary initial phase the application of one or more of said control signals to one or more corresponding actuators with temporary setting values modified with respect to the values defined in said control signals as a function of said setting signals,
  • said variations being defined experimentally during a calibration cycle and being constituted by incremental variations or by decremental variations with respect to the values defined as a function of the setting signals.

As already defined above, the variable values defined in the control signals of the actuators, as a function of the setting signals, are values of parameters of said control signals which define one or more of the following operating conditions:

• • the direction of the deviation flow, that is of the rotation of the propellers;
  • the thrust intensity exerted by said flow, that is of the number of revolutions of the engine or of the propellers of the bow-thruster and/or of the stern-thruster;
  • the direction of the deviation flow, that is of the rotation of the propellers of one or of both propulsion engines;
  • the thrust intensity exerted by said propulsion flow of each of said two propulsion engines, that is of the number of revolutions of the engine or of the propellers of each of said two engines;
  • the steering angle of one or of both engines;
  • the method providing that in said initial phase of application of the control signals one or more of said values are varied in the sense of an increment or of a decrement of the corresponding value with respect to that defined as a function of the corresponding one or more setting signals of said target displacement and in particular said values are respectively increased or decreased in a measure defined experimentally and specific for each or for a predetermined combination of said values.

Said temporary initial phase may for example provide to increase the intensity of the deviation flow, that is of rotation of the propeller of a bow-thruster or of a stern-thruster at the moment of a command of rotation of the vessel around a vertical rotation axis, to overcome the inertia to the variation of the vessel. Typically this initial phase may provide a duration below about twenty seconds and preferably in the time range between one and about ten seconds.

In the case of the execution of a displacement of the vessel from a condition in which the vessel is stationary, the initial phase may provide an increment both of the thrust intensity of the deviation and/or propulsion flows generated respectively by the bow-thruster and/or by the stern-thruster and by one or both engines, that is an increment of the number of revolutions of the corresponding engine and/or of the corresponding propeller and also, as regards the two propulsion engines, a setting of the steering angles thereof such as to increase the component of the thrust generated by said engines according to the displacement direction set by the setting members as a function of which the control signals are generated. The ratio between increment of the thrust exerted by the bow-thruster and/or the stern-thruster and by one or both propulsion engines and the corresponding initial increment or decrement is defined by the translation direction set by the setting members of the target displacement of the vessel.

In the case of a rapid reduction of the translation speed of a vessel and in which the difference between the initial speed and the final, target speed, is relatively large, the method provides that in the temporary initial phase at the moment of the application of one or more commands of reduction of said speed, before the reduction of the propulsion thrust intensity of one or of both engines, possibly combined with a reduction of the thrust intensity exerted by the bow-thruster and/or by the stern-thruster, a command of inversion of the propulsion flow direction of one or of both engines is applied, possibly combined with a command of inversion of the deviation flow of the bow-thruster and/or of the stern-thruster and optionally also alternatively or in combination with a command of variation of the steering angle of one or of both engines, said variation of said one or more steering angles being realized in such a way as to invert at least some components of the propulsion flow of one or of both engines. This combination allows to exert a sort of braking action of the vessel, before applying the values of the operating conditions of the bow-thruster and/or of the stern-thruster and/or of one or of both engines defined by the command signal and/or by a combination of command signals.

In one embodiment of the method it is provided to set a minimum value of the thrust intensity of the deviation flow of the bow-thruster and/or of the stern-thruster and/or of that of propulsion of one or of both engines, while the thrust in a predetermined direction of translation of the vessel, that is the speed in said translation direction, is further reduced by modifying the steering angle of the same with respect to that of the other engine, that is in such a way that the engines present steering angles asymmetrical with respect to the central longitudinal axis of the vessel, the modification of the steering angle of said at least one engine being executed in such a way as to generate a resultant of the displacement of the vessel in the set target displacement direction which corresponds to a lower intensity of said thrust in said direction and/or a lower displacement speed of the vessel in said direction in combination with a number of revolutions of the engine or of the propeller corresponding to the minimum number of revolutions set or not lower than said minimum number of revolutions set.

According to the present invention, when it is desired to obtain translation movements of the vessel, also called lateral translations or “sideways”, having a transversal displacement direction that is with a displacement direction of the vessel having a predetermined angle with respect to the orientation of the longitudinal axis of the vessel, among which, in particular, a displacement direction perpendicular to said longitudinal axis of the vessel, the governing command provides for the angular positioning of the engines according to two steering directions not parallel to each other, the two directions being oriented according to opposite steering angles with respect to said central longitudinal axis of the vessel, and said steering angles being settable with steering angles the amplitude of which is identical or different with respect to the central longitudinal axis of the vessel, that is said steering angles of said two engines being symmetrical or asymmetrical with respect to said central longitudinal axis of the vessel, while in combination with said positioning of the engines according to said two steering directions not parallel to each other, each engine is set independently of the other in forward gear condition and/or in reverse gear condition and/or in neutral condition and/or each engine is adjusted independently of the other on a predetermined number of revolutions and while for said bow-thruster and/or for said stern-thruster it is provided in combination that the respective drive engines of the propellers thereof are set independently in a forward gear condition or reverse gear condition or neutral condition and/or independently on a predetermined number of revolutions in such a way as to generate thrust forces of the vessel having transversal components to the longitudinal axis of the vessel and parallel to the desired transversal translation direction, while,

• • the steering angles of the two engines being primarily or initially symmetrical, said angles being varied in such a way as to have asymmetrical magnitudes with respect to said central longitudinal axis of the vessel, in such a way as to generate at least one component of the propulsion flow of at least one of said engines which causes a reduction of the advancement thrust of said vessel in the translation direction when the displacement speed of the vessel is higher than a desired speed and the engines are regulated to the minimum value of the number of revolutions, that is of the thrust exerted by the propulsion flow thereof and cannot be further reduced.

In combination with the steering of the two engines with asymmetrical steering angles with respect to each other, it is also possible to provide to operate the engines with an identical or different number of revolutions for each engine.

By varying alternatively or in combination the two steering angles of the two engines, the gear direction of the two engines and the number of revolutions, that is the power of the two engines and also by varying according to a synchronization function also the setting of forward gear, reverse gear and neutral as well as optionally also of the number of revolutions of the propeller of the bow-thruster and/or of the stern-thruster, it is possible to obtain different displacement directions of the vessel and in particular also different directions of transversal translation of the vessel and it is also possible to combine a rotation of the vessel around a dynamic center of application of the propulsion forces acting on the hull thereof. This therefore allows obtaining displacements of the vessel substantially according to a large part of the displacements provided in the prior art with two engines and optionally also with a bow-thruster and/or with a stern-thruster such as, for example, those indicated in FIG. 1.

The displacement of the vessel according to a transversal direction to the hull and with an orientation of the transversal direction purely perpendicular to the longitudinal axis of the hull or with an orientation of the transversal translation direction according to directions having at least one directional component perpendicular to the longitudinal axis of the hull are particularly important because they allow to perform maneuvering movements of the vessel during the docking phases for mooring or for the approach to other vessels or to landing points and also for the compensation of external forces to the vessel which cause involuntary translations thereof, as in the case of wind and/or currents.

Furthermore, the aforementioned translation movement, in particular combined with other degrees of freedom of displacement of the vessel as shown for example by the table of FIG. 1, also allows to maintain the vessel in a fixed position and this both when the vessel is not anchored to the seabed and also when it presents an anchoring point to the seabed and in combination to maintain fixed or to vary in a predetermined way the orientation of the longitudinal central axis of the vessel.

The command of alternative variation of the above-mentioned parameters, that is of the steering direction between two opposite steering directions and/or between the two gear conditions, that is forward gear and reverse gear and/or between the different power settings delivered by the two engines, that is of the number of revolutions in the case of propeller engines, may be executed manually directly by the person governing the vessel.

Said command may be executed by using the traditional command members, such as levers, bars or steering wheels present in the command stations of the vessels. However, it is preferable to use, as command member, a single device which is constituted, for example, by a joystick, which generates command impulses containing command information relative to the steering angles and to the gear direction settings and to the delivered power, and which impulses are decoded and read in a control unit which generates selective command impulses for one or more of the actuators of regulation of the operating conditions, such as for example one or more of the following actuators: independent steering actuators from each other of said two propulsion engines, actuators of commutation of the gear direction, that is of the deviation flow of the bow-thruster and/or of the stern-thruster and/or of the propulsion flow of one or of both propulsion engines and/or of the neutral condition, actuators of power command of the engines, that is of the thrust intensity exerted by the deviation flows and/or of the propulsion flows such as for example of variation of the number of revolutions of the propeller and which command impulses are correlated to the displacement direction of the vessel and to the power or speed of displacement thereof reproduced by the direction of inclination of the lever of the joystick and/or by the inclination angle of the lever of the joystick relative to the vertical rest position and/or by the rotation of the lever of the joystick around its own axis.

Other degrees of freedom of the joystick may be provided such as for example also command buttons integrated in the support base of the lever of the joystick and/or on the lever itself of the joystick which for example allow modifying operating conditions of the bow-thruster and/or of the stern-thruster and/or settings of the governing modes between a cruising mode and a maneuvering mode.

Said settings relative to the cruising modes and to the maneuvering modes may be configured and stored in a control program executed by the control unit and may comprise limitations and exclusions of predetermined combinations of settings which are not recommended or even dangerous in the cruising mode and/or in the maneuvering mode.

In one embodiment, the lever of the joystick is rotatable around its axis and the rotation direction, for example right or left, generates setting signals of the rotation direction of the vessel around a vertical axis, while the angular amplitude of the rotation arc generates setting signals of the thrust intensity in rotation and/or of the speed of the corresponding rotation of the vessel, said setting signals being processed into command signals of one or more actuators which set the operating conditions of the bow-thruster and/or of the stern-thruster and/or of one or of both engines in such a way as to obtain the desired rotational displacement corresponding to the rotation of the lever of the joystick.

The generation of the command signals of the operating conditions of the bow-thruster and/or of the stern-thruster and/or of one or of both engines such as the command signals of said one or more actuators is executed by a control unit which executes a control software comprising the instructions of execution of one or more processing algorithms which generate said commands, that is said control signals as a function of setting signals.

As indicated above, the setting signals are generated by manual operation of one or more setting members or by means of an integrated setting member such as for example said joystick.

According to an advantageous embodiment, the control unit is provided in combination with a control software which comprises a plurality of predetermined routine programs in which the control instructions of the steering actuators and/or of the actuators of the gear direction setting for the engines and/or for the bow-thruster and/or the stern-thruster as well as for the setting of the delivered power by the engines and/or by the bow-thruster and/or by the stern-thruster are integrated and coded in order to obtain the displacement of the vessel corresponding to the position parameters of the joystick relative to the different degrees of freedom of displacement provided for the lever and/or to the commutation of one or more buttons optionally provided on the joystick.

In particular, when the lever of the joystick is moved to obtain a transversal translation of the vessel in a predetermined direction, such position of the joystick lever activates the execution of a routine, already programmed, by the control unit, which routine already comprises the setting commands of the steering direction of said two engines respectively in one of the two steering directions diverging or converging with each other and/or of the setting of the gear directions and/or of the neutral condition or for the setting of ranges of variation of the power respectively independently from each other and according to a predetermined synchronization function, of the engines and/or of the bow-thruster and/or of the stern-thruster, the steering angles in one or both steering directions of the engines and/or the power delivered by the engines and/or by the bow-thruster and/or by the stern-thruster remaining for example variable.

In this way the steering actuators are automatically commanded in such a way as to position the two engines according to the respective steering direction of said two diverging or converging steering directions by setting a predefined steering angle for each of said two steering directions and/or by setting predetermined gear directions and predetermined numbers of revolutions of the engines and/or of the bow-thruster and/or of the stern-thruster, while other functional parameters are variable as a function of the parameters describing the position of the joystick and which correspond to variations of the steering angles of one or both said steering directions with respect to those predefined in the programmed routine and/or between the two opposite gear directions within the admissible ranges and/or to the variations of the power delivered by the engines and/or by the bow-thruster and/or by the stern-thruster with respect to the predefined settings provided in said programmed routine.

The parameters relative to said admissible variation ranges may be set at the time of the installation of the control unit and may also be modified in order to be further adapted to the specific characteristics of the vessel and of the engines and/or of the bow-thruster and/or of the stern-thruster provided for the same.

The admissible ranges may also be automatically modifiable on the basis of variation commands which provide for a variation of the set variation range for example due to the choice of a governing mode such as the cruising mode or the maneuvering mode and/or due to particular weather and sea conditions, such as for example the wind conditions and/or the sea wave conditions and other conditions influencing the navigation.

In one embodiment the method provides to automatically detect by means of sensors one or more of the different parameters provided in the following list:

• • position coordinates of the vessel relative to a GPS system or similar and/or relative to surveys of the morphology of the coast or of stationary installations or other references that can be considered stationary and which may be captured in the frames of a video camera;
  • distance of the vessel from one or more stationary references and/or presence of said references and/or floating obstacles such as for example buoys, debris or the like;
  • variations of the acceleration of the vessel both relative to the intensity and relative to the direction;
  • orientation of the bow of the vessel, that is of the longitudinal axis of the vessel with respect to the earth magnetic field, i.e. the compass angle;
  • wind direction and speed;
  • current direction and speed;
  • variations of the trim of the vessel, such as inclinations thereof.

As regards the detection of the different parameters, the sensors are known.

The position of the vessel may be determined by GPS sensors.

The position may also be determined by triangulation relative to different geographic references framed in the frames of at least one onboard camera and whose position coordinates are known and/or whose outline is detected with a predetermined frequency, the variations thereof in the succession of frames being determined and the speed and the direction of relative displacement of the vessel being extracted from said variations.

The distance from stationary references external to the vessel may be detected either by said triangulations or by distance sensors.

Camera systems may also be configured to detect the presence of stationary and non-stationary floating obstacles such as for example buoys, floating debris or the like.

In addition or alternatively to the camera systems, the vessel may also be provided with remote sensing systems of LIDAR type or the like.

Relative to the accelerations undergone by the vessel, combinations of accelerometers are known in the prior art which detect accelerations of a body in the three-dimensional or two-dimensional space. Such accelerometers may also be used to acquire temporal trends of the three-dimensional accelerations of the vessel and to determine therefrom the condition of the sea wave motion.

The compass angle, that is the orientation of the longitudinal axis of the vessel is measured by one or more onboard compasses, while the wind direction and speed are detectable respectively by an anemometer.

The trim of the vessel is measurable by means of combinations of inclinometers.

The speed and the direction of the current may be calculated on the basis of the measurement parameters relative to the position and/or relative to the accelerations of the vessel.

In one embodiment, all or at least some of these parameters may be detected and the results of the measurements and/or of the parameters extracted from these measurements may be displayed for the person governing the vessel.

In one embodiment, said measurement parameters or the parameters obtained from the processing of those measured are automatically processed by the control unit which executes an automatic control software comprising the instructions to automatically generate command signals of the steering actuators of the two engines and/or of the setting of the gear direction of the two engines and/or of the bow-thruster and/or of the stern-thruster or of neutral and/or of the power delivered by the two engines and/or by the bow-thruster and/or by the stern-thruster in such a way as to generate propulsion forces of the vessel to compensate involuntary displacements thereof and/or to control the displacements of the vessel in the execution of maneuvers such as docking or the like in a way corresponding to the environmental conditions and to the relative position of the vessel with respect to a target position which may be for example the docking to a mooring site and/or to an anchoring site and/or also to a further craft.

According to one embodiment, the automatic mode of setting may be activatable and deactivatable by command from the person governing the vessel and/or it may be activatable and deactivatable as a function of the fact that the command member, for example the joystick, remains in the neutral position or the same is operated by moving the lever according to one of the degrees of freedom thereof and/or if a command member of those traditionally provided such as the levers of variation of the power delivered by the engines and/or the manual steering member and/or the command member of the bow-thruster and/or of the stern-thruster is operated. In all cases in which there is no actuation of one of said command members, the automatic mode may remain active, while it is automatically deactivated switching to the manual mode according to one or more of the above-described variants when at least one of said command members is operated.

Some terms used in the present description and in the claims are to be considered equivalent and therefore the use of one of these terms automatically implies the use of the equivalent terms. In particular the following terms are to be considered equivalent:

• • direction of the deviation flow or of the propulsion flow generated respectively by the bow-thruster or by the stern-thruster and by each of the two engines, direction of rotation of the propeller respectively of the bow-thruster or of the stern-thruster and of each of the two engines and gear direction of the engine or of the vessel as a consequence of the propulsion flow;
  • thrust intensity exerted by the deviation flow or by the propulsion flow generated respectively by the bow-thruster or by the stern-thruster and by each of the two engines, number of revolutions of the engine of the propeller respectively of the bow-thruster or of the stern-thruster and of each of the two engines;
  • in the condition in which the engines are not parallel but oriented divergent with respect to each other towards stern or towards bow, equal steering angles of said engines is equivalent to symmetrical steering angles of said engines with respect to the central longitudinal axis of the vessel;
  • in the condition in which the engines are not parallel but oriented divergent with respect to each other towards stern or towards bow, different steering angles of said engines is equivalent to asymmetrical steering angles of said engines with respect to the central longitudinal axis of the vessel.

Furthermore, a steerable propulsion engine is equivalent to a propulsion engine having a non-steerable axis or which generates a non-orientable propulsion flow in combination with a rudder blade immersed in said propulsion flow and orientable with respect to said flow in different angular positions with respect to a steering axis having at least one predominant directional component oriented vertically.

The invention also relates to a system of governing a vessel for the implementation of the method according to one or more of the above-described embodiments and variants.

In one embodiment said system is provided in combination with a vessel or the like comprising at least one bow-thruster and/or at least one stern-thruster, provided respectively at the bow area and at the stern area of the vessel and two engines at least steerable independently from each other, which system comprises:

• • an independent steering actuator for each of the two engines and which commands the steering mechanism of respectively one of said two engines;
  • and/or an independent commutation actuator of the gear direction for each of said two engines which commands the commutation mechanism of the gear direction of respectively one of said two engines, that is the commutation of the propulsion flow direction, such as in particular the direction of rotation of the propeller and/or the direction of a jet of propulsion of a jet engine;
  • and/or an independent actuator commanding the delivered power for each of said two engines, that is of the thrust intensity of the propulsion flow or of the number of revolutions of the engine or of the propeller and which commands the regulation mechanism of said delivered power of respectively one of said two engines;
  • a commutation actuator of the rotation direction of the propeller of said bow-thruster and/or of said stern-thruster and/or a command actuator of the delivered power by said bow-thruster and/or by said stern-thruster, that is of the thrust intensity of the deviation flow such as the number of revolutions of the engine or of the propeller;
  • independent regulation organs of the steering direction of each of said two engines independently from each other;
  • and/or at least one organ or a combination of several separate members of generation of one or more setting signals of a target displacement of the vessel, said target displacement also comprising the maintaining of the position of the vessel and/or the maintaining of the orientation of the central longitudinal axis of the vessel, said one or more setting signals comprising setting information of parameters of the operating conditions of respectively the bow-thruster and/or the stern-thruster and/or of one or of both engines, said operating conditions comprising setting information or variation to be applied independently or in combination with each other consisting of:
  • information on the steering angle to be applied for one or both engines,
  • information on the gear direction and/or of setting of the neutral condition of each of said two engines also independently from each other,
  • information on the setting or the variation of the power delivered by said two engines, that is on the thrust intensity of the propulsion flow or on the number of revolutions of the engine or of the propeller of each of said two engines independently from each other,
  • information on the setting of the direction of the deviation flow, that is of the rotation direction of the engine and/or of the propeller of the bow-thruster and/or of the stern-thruster,
  • information on the setting or variation of the delivered power or on the number of revolutions of the engine or of the propeller of the bow-thruster and/or of the stern-thruster,
  • a control unit in which is loaded a control program which comprises the processing instructions of said one or more setting signals generated by said one or more setting members of a target displacement of the vessel to generate as a function thereof one or more setting information of the corresponding command signals of one or more of said actuators in such a way that the thrust exerted on the vessel determines a displacement thereof corresponding to the target displacement set by means of said setting members, and in which
  • to said control unit there is associated a clock or said control unit comprises a clock and at least one setting interface of the settable duration of a temporary initial period of application of said one or more command signals to one or more of said actuators, said clock measuring said duration starting from the instant of application of said command signals to said one or more actuators,
  • and said control program comprises instructions to increase or reduce and/or invert in a predetermined and settable measure the operating conditions defined by said one or more setting information of said one or more actuators defined by said one or more command signals generated by said processing of said one or more setting signals,
  • while the activation of said clock is caused by said application of said one or more command signals to said one or more actuators and the control unit is configured to cancel said increment or decrement or inversion applied to said one or more command signals during said period when the clock has measured said duration,
  • said control unit being provided or connected or connectable to a setting interface of the measure of said increment and/or decrement and/or inversion.

In one embodiment, said setting members of a target displacement of the vessel may be constituted by a combination of members each intended for the generation of setting signals of at least one of the aforesaid conditions of the bow-thruster and/or of the stern-thruster and/or of one or both engines, or alternatively said setting members are constituted by a single unified command device which comprises a command organ which is movable according to different degrees of freedom relative to a neutral position, that is inactive of command, and each one corresponding to a displacement direction of the vessel with a power of execution of said displacement, and which unified command device generates command signals in which the command information of said one or more actuators are encoded, said unified command organ being configured as a joystick or the like;

• • said command program further comprising the instructions of decoding of the setting commands generated by said unified command organ for said one or more actuators and a plurality of predetermined routines which contain the setting instructions of a combination of two or more of said actuators in such a way as to actuate the actuators of said combination in a synchronized way with each other in order to obtain a displacement of the vessel according to the direction and/or with the propulsion power corresponding to the displacement of said unified setting organ relative to said neutral position thereof.

In a preferred embodiment the command device may be operated to set a transversal displacement direction of the vessel having at least one directional component perpendicular to the longitudinal axis of the vessel or substantially perpendicular to said longitudinal axis, being activated by said setting organ the execution of a corresponding routine of the command program executed by the control unit, which routine comprises the instructions to actuate in synchronized way at least the steering actuators of one or both engines to assume two steering directions not parallel with each other, in particular diverging and/or converging with each other of said two engines, with respectively a predetermined steering angle, said steering angles being variable upon command of said setting organ within predetermined ranges of steering angles corresponding to predetermined translation directions relative to the orientation of the longitudinal axis of the vessel.

According to a further characteristic said routine comprises in combination the instructions to command in any combination with each other and with different sequences of synchronization the steering actuators, the gear direction switching actuators, that is of the direction of the propulsion flow of one or both engines, that is of the direction of rotation of the propellers and/or of the neutral condition, and optionally the gear direction switching actuators, that is of the direction of the deviation flow, that is of the direction of rotation of the propellers of the bow-thruster and/or of the stern-thruster;

• • and optionally in combination or alternatively the power command actuators of the delivered power, that is of the thrust intensity of the propulsion flow such as the number of revolutions of the engine or of the propellers of one or both propulsion engines and optionally the power command actuators of the delivered power, that is of the thrust intensity of the deviation flow such as the number of revolutions of the engine or of the propellers of the bow-thruster and/or of the stern-thruster, varying said power within a predetermined range and according to a predetermined variation function.

According to a further characteristic, to the control unit are connected at least one man-machine communication interface comprising members of input and/or loading of commands and/or settings, such as for example a keyboard, and members of display and/or signaling of the set conditions.

According to a further characteristic of the system which may be foreseen in combination with one or more of the preceding characteristics, the system comprises one or more detection sensors, activatable manually or automatically, for the measurement or detection of one or more of the different parameters and which sensors are of the type foreseen in the following list:

• • detection sensors of the position coordinates of the vessel relative to a GPS system or the like and/or relative to topographic surveys, such as for example the detection of the morphology of the coast or of stationary installations or other references that can be considered stationary and which may be captured in the frames of a video camera;
  • sensors of measurement of the distance of the vessel from one or more stationary references;
  • sensors of acceleration of the vessel in one or more directions in space, both relative to the intensity and relative to the direction;
  • one or more magnetic and/or gyroscopic compasses;
  • sensors of the direction and of the speed of the wind;
  • sensors of the direction and speed of the current;
  • sensors of the variations of the trim of the vessel, such as inclinations thereof;
  • said control unit being provided with at least one or more inputs for said one or more sensors and in said control unit being loaded the programs which contain the instructions to manage the functionalities of said one or more sensors and/or to receive the signals generated by said sensors;
  • in said control unit being loaded or loadable and said control unit executing a control program which comprises the instructions for the processing of one or more of said measurement signals of said one or more sensors and for the generation or the automatic variation of setting signals and/or of the command signals of one or more of said actuators as a function of the measurement signals generated by said one or more sensors and/or of the temporal variations of the signals of said one or more sensors, which automatic setting signals and/or automatic command signals generated as a function of said measurement signals of said one or more sensors are applied to said one or more actuators alternatively to the command signals generated by the manual setting signals generated by said one or more setting members of a target displacement of the vessel or are applied in combination with said command signals generated by the manual setting signals generated by said one or more setting members of a target displacement of the vessel as correction signals which modify the settings as a function of the navigation and environmental conditions detected by said one or more sensors.

In one embodiment, an automatic selection of the alternative or combined application of the command signals generated as a function of the measurement signals of one or more sensors is provided, which is activated as a function of a variation in time of the measurement signal of at least one or of a certain number of said one or more sensors.

In an alternative operating mode, the automatic selection and the automatic execution of a combination of one or more automatic commands generated as a function of the measurement signals of one or more sensors with one or more command signals generated as a function of the setting signals of a target displacement of the vessel generated by means of one or more manual setting members is executed as a function of the setting of target values of one or more of the measurement signals which are different from starting values and which are settable by the operator.

A hybrid mode is also possible which provides for some parameters, such as for example the position of the vessel, to set fixed target values and to provide for the automatic generation of one or of a combination of command signals of one or more of the actuators configured in such a way as to satisfy the achievement of said fixed target values and which can be varied manually or automatically in order to operate in the sense of counteracting variations of the effective displacement of the vessel with respect to the set target displacement that exceed ranges of maximum permitted variation.

In one embodiment, to the control unit is connected or connectable an input interface of a predetermined minimum and/or maximum limit of the power delivered by one or by both said propulsion engines and/or by the bow-thruster and/or by the stern-thruster, that is of the minimum and/or maximum settable number of revolutions of said engines and/or of said propellers, while the command unit executes a command program which configures it to modify the steering angle of at least one of said two engines relative to that of the other of said two engines in such a way as to have different steering angles for said two engines and asymmetrical relative to the central longitudinal axis of the vessel in order to further slow down the speed of displacement of the vessel maintaining said minimum number of revolutions and generating with one of said two engines a component of the propulsion flow which counteracts the set displacement of the vessel.

The invention also relates to a system for governing a vessel for implementing one or more embodiments of the method described herein, which system is provided in combination with a vessel or similar craft comprising at least one bow-thruster and/or at least one stern-thruster respectively positioned in correspondence with the bow area and the stern area of the vessel, and two engines at least steerable independently from each other, the system comprising:

• • an independent steering actuator for each of the two engines, each actuator commanding the steering mechanism of a respective one of said two engines; and/or
  • an independent gear-direction switching actuator for each of said two engines, each actuator commanding the gear-direction switching mechanism of a respective one of said two engines, that is, the switching of the direction of the propulsion flow, in particular the direction of rotation of the propeller and/or the direction of a propulsion jet of a jet engine; and/or
  • an independent power-control actuator for each of said two engines, namely for controlling the intensity of the thrust of the propulsion flow or the number of revolutions of the engine or the propeller, each actuator commanding the regulation mechanism of the delivered power of a respective one of said two engines; and/or
  • a rotation-direction switching actuator for the propeller of said bow-thruster and/or said stern-thruster and/or a power-control actuator for said bow-thruster and/or said stern-thruster, namely for controlling the thrust intensity of the deviation flow such as the number of revolutions of the motor or the propeller;
  • independent adjustment members for the steering direction of each of said two engines, each independently of the other; and/or
  • at least one member, or a combination of a plurality of separate members, for generating one or more setting signals of a target displacement of the vessel, said target displacement also comprising the maintenance of the position of the vessel and/or the maintenance of the orientation of the longitudinal central axis of the vessel, wherein said one or more setting signals comprise setting information of parameters of the operating conditions of respectively the bow-thruster and/or the stern-thruster and/or one or both of the engines, said operating conditions comprising setting or variation information to be applied independently or in combination, consisting of:
  • information on the steering angle to be applied to one or both of the engines;
  • information on the travel direction and/or the setting of the neutral condition of each of said two engines, also independently of each other;
  • information on the setting or variation of the delivered power of said two engines, namely on the intensity of the thrust of the propulsion flow or on the number of revolutions of the engine or the propeller of each of said two engines independently of each other;
  • information on the setting of the direction of the deviation flow, that is, the direction of rotation of the motor and/or of the propeller of the bow-thruster and/or the stern-thruster;
  • information on the setting or variation of the delivered power or on the number of revolutions of the motor or propeller of the bow-thruster and/or the stern-thruster;
  • a control unit in which a control program is loaded, the program comprising instructions for processing said one or more setting signals generated by said one or more setting members of a target displacement of the vessel to generate, as a function thereof, one or more corresponding setting information items and one or more command signals for one or more of said actuators, in such a way that the thrust exerted on the vessel determines a displacement thereof corresponding to the target displacement set by said setting members;
  • wherein said control unit is connected or connectable to an input interface for entering a predetermined minimum and/or maximum limit of the power delivered by one or both of said propulsion engines and/or by the bow-thruster and/or the stern-thruster, namely of the minimum and/or maximum number of revolutions settable for said engines and/or said propellers, while the control unit executes a control program that configures it to modify the steering angle of at least one of said two engines relative to the other of said two engines so as to obtain different steering angles for said two engines and asymmetrical with respect to the longitudinal central axis of the vessel, in order to further reduce the speed of displacement of the vessel while maintaining said minimum number of revolutions and generating, with one of said two engines, a component of the propulsion flow that counteracts the set displacement of the vessel.

BRIEF DESCRIPTION OF THE DRAWINGS

These and other characteristics and advantages of the present invention will become clearer from the following description of some embodiments illustrated in the attached drawings in which:

FIG. 1 shows a table which summarizes the resultant displacement direction of a vessel provided with two steerable engines as a function of the steering direction of said two engines, of the forward gear and/or reverse gear and/or neutral set for each engine according to the prior art.

FIG. 2A illustrates the forces acting on the center of application of the forces Cf of the hull of the vessel with reference to an embodiment of the present invention in which two outboard engines are foreseen, steerable independently from each other.

FIG. 2B illustrates, similarly to FIG. 2A, a condition of different steering angles of the two engines and asymmetrical relative to the central longitudinal axis of the vessel.

FIG. 3 shows an embodiment of a system configured to actuate the method according to the present invention.

FIG. 4 is a flow diagram of a possible embodiment of execution of the method of governing according to the present invention.

FIG. 5 is a flow diagram of an example of the steps of execution of governing of the vessel according to an embodiment of the present invention in which a temporary initial phase of increment/decrement or inversion of the settings of one or more actuators relative to the settings defined by means of the manual setting members of the target displacement and/or automatically by the command unit is foreseen.

FIG. 6 shows, similarly to FIG. 5, a flow diagram of an example of the steps of execution of governing of the vessel according to an embodiment of the present invention in which a steering of the two propulsion engines with steering angles asymmetrical relative to the central longitudinal axis of the vessel is foreseen in order to reduce the speed of the effective displacement of the vessel when the minimum number of revolutions of said engines has been reached.

DETAILED DESCRIPTION OF EMBODIMENTS OF THE INVENTION

With reference to FIG. 1, a vessel 1 comprises as propulsor two outboard engines 2, 4 which are secured to the transom 101 in such a way as to be steerable independently from each other in order to orient the rotation axis of the propeller 201, 401 according to different directions in a substantially horizontal plane, that is transversal to the plane of the transom and/or to the steering axis. Preferably, but not necessarily, the two engines are positioned symmetrically with respect to the central longitudinal axis of the vessel.

A substantially equivalent embodiment is constituted by an inboard-outboard type engine, in which the engine is foreseen stationary inside the vessel 1, while the engine shaft extends thanks to a transmission into a foot external to the vessel which contains the drive shaft of the propeller and which is connected to the engine shaft by means of a joint which allows the oscillation of said propeller shaft analogous to that of the foot of the outboard engine.

In combination with said two engines 2 and 4 the vessel further comprises a so-called bow-thruster indicated with 6 and which is constituted by a transversal channel that crosses the underwater hull from side to side and inside of which is mounted rotatable around a propeller shaft which is coaxial with the axis of the channel that crosses said underwater hull.

Alternatively or in combination with said bow-thruster 6, the vessel may comprise a so-called stern-thruster indicated with 6′, and which is foreseen in the stern area of the same opposite to the bow area of positioning of the bow-thruster 6 with reference to a transversal axis passing through the center of application of the forces CF foreseen for the vessel.

The combination of the forces exerted on the center of application of the forces CF of the vessel by the propulsion flows generated by the propellers 201 and 401 of the engines 2 and 4 and of the bow-thruster 6 and/or of the stern-thruster 6′ and which may present directions of said flow opposite to each other and/or orientations of the propulsion flow corresponding to predetermined steering angles and/or intensities such as speeds and/or flow rates of said flows determined by the rotation speed (number of revolutions) of the propellers, determines a resultant force which causes the displacement of the vessel according to different directions and/or with different orientations of the longitudinal axis of the hull and/or of the displacement direction of the hull relative to the orientation of the longitudinal axis of the hull.

By center of application of the forces Cf is meant a point of the vessel, generally provided in a predetermined position, between the stern and the bow and coinciding with the median longitudinal axis of the hull of the vessel, and on which point it is possible to consider that all the thrust forces exerted on the hull of the vessel act determining the displacement thereof according to different directions, that is heading angles, and/or according to different directions relative to the orientation of said median longitudinal axis of the hull and/or according to different trajectories.

The illustrated example shows a particular application of the method of governing of the vessel which allows to execute a lateral translation displacement of the vessel in a transversal direction to the median longitudinal axis of the hull. In a particular embodiment said displacement takes place in a substantially perpendicular direction to said median longitudinal axis of the hull, however, as has already been described above, it is possible to set the various forces deriving from the different propulsion engines and from the bow-thruster and/or from the stern-thruster and/or the steering angles of the two propulsion engines in such a way as to obtain translations according to directions not perpendicular to said longitudinal axis of the vessel, but with directions having orientations with directional components perpendicular and parallel to said longitudinal axis.

As shown, the bow-thruster 6 exerts a rotation torque on the center Cf of application of the forces, which torque presents a component ∥t parallel to the longitudinal axis of the vessel and a component in transversal direction I-t.

This applies analogously also for the stern-thruster 6′ when present.

In order to obtain a translation according to a direction substantially perfectly perpendicular to the median longitudinal axis of the vessel, it is necessary to compensate the component of the torque exerted by the bow-thruster and/or by the stern-thruster 6′ which determines the rotation, in such a way as to maintain active for the displacement of the vessel only the component I-t transversal to the longitudinal axis of the vessel.

To this purpose the present invention provides to steer the two propulsion engines according to two steering directions diverging or converging with each other, see the settings of said steering directions of the two engines indicated at the positions A, B, E, F, H, I, J and K of the table of FIG. 1.

The double arrow ST of FIGS. 2A and 2B indicates the steering movement executable independently or in synchrony by said two engines 2, 4.

The steering angles in the two opposite directions of said propulsion engines 2 and 4 may be symmetrical with each other, that is identical relative to the median longitudinal axis of the hull, or also different from each other.

In addition to the above it is possible that the number of revolutions of the propeller 201, 401 of one or both of said propulsion engines 2 and 4 is varied between two different values in the two different steering positions and/or that also the direction of rotation of the propeller is inverted in one of said steering positions relative to the direction of rotation of the propeller of the other engine in combination with said two steering positions as indicated by the aforesaid positions of the table of FIG. 1.

The variation of the number of revolutions of the propeller and/or the setting of one direction of rotation or of the opposite one of the bow-thruster 6 or of the stern-thruster 6′ may also be foreseen in combination with one or more of the variants described above and/or this also according to a predetermined synchronization function with the steering angles and/or with the direction of rotation of the propellers and/or with the number of revolutions of the propellers of the two engines.

With ssx and sdx are indicated the propulsion thrusts generated by the engines 2 and 4 in the two steering positions respectively to the left and to the right; with ∥sx and ∥dx are indicated the components of these thrust forces parallel to the median longitudinal axis of the vessel and acting on the center of application Cf, while with I-sx and I-dx are indicated the components of said two thrust forces ssx and sdx which are perpendicular to the median longitudinal axis of the vessel.

In Figure A1 the condition is shown, in which the direction of rotation of the propeller 201 of the engine 2 is discordant to that foreseen for the propeller 401 of the engine 4.

It is possible to modify the number of revolutions of the propeller 201 of the engine 2 and of the propeller 401 of the engine 4 in one of the two steering positions converging or diverging with each other, or alternatively or in combination to modify the number of revolutions of the propeller of the bow-thruster 6 and/or of the stern-thruster 6′ in such a way as to increase the parallel and perpendicular components of the thrust on the vessel towards left or towards right relative to the parallel and perpendicular components, with the result of not fully compensating the parallel and/or perpendicular components to the longitudinal axis of the vessel of the resultant force applied to the center Cf thereby determining a translation not perfectly perpendicular to said longitudinal axis of the vessel forward and/or backward and/or also optionally a rotation around the center of application of the forces of the vessel due to a torque of the bow-thruster 6 and/or of the stern-thruster 6′ applied to said center of application Cf.

By varying the direction of rotation of the propeller 201 of the engine 2 with respect to that of the propeller 401 of the engine 4 between a condition of discordant drive or concordant drive of said two engines as shown by the arrows RT, it is possible to further modify the displacement trajectories of the vessel in space and/or the angle comprised between said displacement trajectories and the longitudinal axis of the vessel itself and/or by combining translation displacements with rotation displacements of the vessel itself.

The steering angle of each of the two propulsion engines 2 and 4, the direction of rotation of the propeller of each of said two engines, and the number of revolutions of the propeller of each of said two engines constitute the parameters which define the operative conditions of each of said engines 2 and 4.

Analogously, the direction of rotation of the propeller of the bow-thruster and/or of the stern-thruster and the number of revolutions of said propeller, i.e. of the corresponding engine, constitute the parameters which define the operative conditions of the bow-thruster and/or of the stern-thruster, and the setting commands of the target displacement of the vessel comprise setting commands or variation commands of one or more of said parameters depending on the type of target displacement among those possible as shown in the examples of FIG. 1.

According to a further possible embodiment provided in combination with one or more of the previous embodiments and/or variant embodiments, all the settings and/or the ranges of variation of one or more of said parameters which define the operative conditions of each propulsion engine 2 and 4 and/or of the bow-thruster and/or of the stern-thruster may be set alternatively with each other or in combination of two or more of them, to different values for different governing conditions, that is displacement conditions of the vessel, such as for example maneuvering conditions and/or cruising conditions and/or position-maintaining conditions, and the values of these parameters may also be modified as a function of parameters which define the atmospheric conditions, such as presence of wind and of the sea such as wave motion or presence of currents.

According to a first embodiment, the steps of the method may be executed in a completely manual way, being provided setting members of the angle and of the steering direction of each engine, setting members of the number of revolutions of the propeller, setting members of the forward or reverse gear of each propulsion engine such as, for example, actuators of switching of the direction of rotation of the propeller between two opposite directions of rotation and/or into a neutral condition, and activation members of the bow-thruster and/or of the stern-thruster as well as setting members of the number of revolutions of the propeller and/or of the direction of rotation of the same of said bow-thruster and/or of said stern-thruster.

All said setting members may be constituted by combinations of different setting members, each of which generates setting signals of one or of a combination of a partial number of the parameters which define the operative conditions of the propulsion engines and/or of the bow-thruster and/or of the stern-thruster such as, for example, levers, tillers, steering wheels or wheels and/or manually operable switching members. The number of revolutions and the direction of rotation of the propellers and the possible variations of these functional parameters in combination with the steering modes of the engines, such as the steering angles in the two steering positions, of the engines may be controlled on the basis of direct sensory feedback of the person governing the vessel as well as on the displacement effect of the vessel detected visually by the person governing the vessel and/or measured by means of one or more sensors of the actual displacement conditions of the vessel and/or of the setting of one or more of the actuators.

For example, during a docking maneuver of the vessel, such as the approach to a quay, the feedback on the movement of the vessel relative to the target position is directly detectable by sight, and therefore the person governing the vessel may carry out the corrections eventually required to the various operative parameters by acting manually on one or more of said setting members and in the sense of modifying the actual displacement of the vessel.

In an advantageous embodiment it is preferable to provide a single integrated control member, in particular in the form of a joystick which generates command signals for motorized actuators of steering, of switching of the forward/reverse gear and/or of neutral, of regulation of the number of revolutions of the engine and of the bow-thruster. Members of this type are known since a long time in the field of governing of vessels, boats and ships and are described for example in document U.S. Pat. No. 3,976,023 published in 1976 and in subsequent documents which describe variants of the basic concept of the joystick, from time to time improved on the basis of the new mechanical and electronic technologies available for the improvements of the joysticks, such as for example documents GB2178143, JPH01285486, WO2017136955, U.S. Pat. No. 7,267,068, EP0778196 and others.

In this variant embodiment, the output or outputs of the joystick for a combined command signal and/or for a plurality of separate command signals are connected to an electronic control unit comprising a processing unit in which is loaded or loadable and from which is executed or executable an interpretation program containing the instructions which render said processing unit able to interpret the setting information contained in the combined setting signal or in said plurality of setting signals generated by the joystick, and a control program which contains the instructions which render said processing unit able to generate control signals of one or more of the motorized actuators configured to execute the steering of the engines and/or alternatively or in combination a regulation of the number of revolutions of the propeller, and/or, alternatively or in combination, the switching of the engines between forward gear, reverse gear and neutral, and/or, alternatively or in combination, the activation of the bow-thruster and/or of the stern-thruster as well as the regulation of the number of revolutions of the propeller and/or of the direction of rotation of the same of the bow-thruster and/or of the stern-thruster and/or the switching between two opposite directions of rotation of the propeller of the bow-thruster and/or of the stern-thruster.

In one embodiment, said interpretation and control programs may integrate, for example in the form of previously programmed and activatable command routines, as a function of the setting signal or of the setting signals generated by the joystick and processed by means of the interpretation program, some integrated command functions or cycles of the propulsion engines and/or of the stern-thruster and/or of the bow-thruster, such as for example, alternatively and/or in combination with each other, one or more of the following functionalities:

• • the automatic command routines of the setting of the steering direction of the propulsion engines according to a mode in which the engines present concordant and/or parallel steering directions or discordant steering directions, that is converging or diverging from each other;
  • the setting of the steering angles in each of said two concordant and/or discordant steering positions of the two engines one with respect to the other;
  • the possible variation of the number of revolutions of the propeller of one or of each of the two propulsion engines and/or of the bow-thruster and/or of the stern-thruster;
  • the switching between forward gear, reverse gear and neutral of one or of each of the two engines and/or of the bow-thruster and/or of the stern-thruster;
  • the selection of a synchronizations function among a plurality of different predefined synchronization functions which correspond to predetermined execution sequences of different setting commands of the steering directions of the two propulsion engines and/or execution commands of said variations of the number of revolutions of the propeller of the propulsion engines and/or of the bow-thruster and/or of the stern-thruster and switching commands between forward gear, reverse gear and neutral of the propulsion engines and/or of the bow-thruster and/or of the stern-thruster.

Said synchronization functions and the usable values or the setting ranges of said values of the parameters relating to the steering angles in said concordant or discordant steering directions of the two engines, to the variation of the number of revolutions of the propeller of the propulsion engines and/or of the bow-thruster and/or of the stern-thruster, and to the switching between forward gear, reverse gear and neutral of the propulsion engines and/or of the bow-thruster and/or of the stern-thruster may be established, within limits intrinsic to the structural configurations of the actuators, experimentally at the time of execution of an initial calibration of a governing system configured for the implementation of the method described above.

It is also possible to provide different variation ranges of the values of one or more of said parameters which define the operative conditions of the two engines and/or of the bow-thruster and/or of the stern-thruster, or different combinations of predetermined values of said parameters which are selectable, for example by manual selection by the pilot and by means of selection interfaces, and which different value ranges or which different predetermined values are related to typical governing conditions of the vessel, such as variation ranges of said parameters and/or predetermined values of said parameters suitable for the governing in a maneuvering condition and/or for the governing in a cruising condition and/or for the maneuvering of the vessel both in a maneuvering condition and in a cruising condition with different atmospheric conditions, such as in particular the speed and the direction of the wind and/or with different sea conditions, that is the wave motion and/or marine currents.

In one embodiment, the selection among said different variation ranges and/or among said different combinations of predetermined values may take place manually thanks to selection members and/or also automatically thanks to a combination of sensors which allow to detecting automatically said governing conditions.

In one embodiment of the invention, in fact, to the central control unit is connected a combination of one or more different sensors which detect physical quantities inherent to the movement conditions of the vessel and/or to the meteo-marine conditions in which the vessel is located and/or to the position conditions and/or to the state of the steering actuators of the propulsion engines, and/or of the actuators of regulation of the number of revolutions of the propeller, and/or of the actuators of switching of the propulsion engines and/or of the bow-thruster and/or of the stern-thruster between forward gear, reverse gear and neutral, and/or of the actuators of activation of the bow-thruster and/or of the stern-thruster as well as of regulation of the number of revolutions of the propeller and/or of the direction of rotation thereof of the bow-thruster and/or of the stern-thruster.

Said one or more different sensors destined to measure and/or detect different physical parameters may be provided in any combination and sub-combination with each other and may be selected for example from the following list:

• • sensors of the position coordinates of the vessel relatively, for example, to GPS signal sensors or the like;
  • position detectors by triangulation of stationary coastal references such as lighthouses or the like;
  • detectors of the position by image processing of recognition of the morphology of the coast in the frames of one or more cameras;
  • sensors of the acceleration of the vessel both with respect to the intensity and with respect to the direction;
  • compasses for measurement of the orientation of the bow of the vessel relative to the earth magnetic field, also called compass angle;
  • sensors of the wind direction and speed;
  • sensors of the current direction and speed;
  • sensors of the variations of trim of the vessel, such as inclinations thereof.

In addition to the combination of one or more of said sensors it is also possible to integrate, as a function of the position of the vessel detected by said sensors, parametric information derived from nautical maps and/or of the meteo-marine conditions and/or of the typical currents present in correspondence with the position of the vessel.

Still according to one embodiment said combination of one or more sensors and/or of the information acquired by means of nautical maps, and/or maps of the meteo-marine conditions and/or maps of the currents may comprise sensors of the vessel motion dynamics constituted by one or more autonomous devices of measurement of the linear acceleration, of the angular acceleration and/or of the magnetic orientation, so-called inertial measurement units (IMU). Said inertial measurement units present the characteristic of operating in absence of external signals or measurement sources and are of current production, commonly used in different sectors and available in multiple product lines such as, for example, iNEMOtm made available by ST Microelectronics.

The signals received from said combination of sensors connected to the central control unit allow selecting different operative modes.

In a manual mode which provides for the manual actuation of a joystick for the governing of the vessel, the signals of the combination of said one or more sensors may be processed in order to modify the values of said setting parameters of the governing system as defined above within said ranges of values defined at the time of installation of the governing system and as a function of the commands generated by the joystick.

It is possible that the person governing the vessel is alerted of this automatic variation of the parameters, which define the operative conditions of the two propulsion engines and/or of the bow-thruster and/or of the stern-thruster, by means of visualization of the data in alphanumeric and/or graphical form on a monitor, optionally together with the combination of parameters measured by said sensors and/or by the images of the cameras and/or other detection systems such as LIDAR or the like and/or by one or more of the position maps and/or maps of the meteo-marine conditions and/or maps relating to the currents.

In this implementing mode it is possible to allow the user to modify the settings determined automatically by the control unit.

The user may select among various visualization modes in which the monitor screen is divided into at least two areas or into a plurality of areas in each of which is displayed a different representation in alphanumeric and/or graphical form on a monitor, together with the combination of parameters measured by said sensors and/or by the images of the cameras and/or other detection systems such as LIDAR or the like and/or by one or more of the position maps and/or maps of the meteo-marine conditions and/or maps relating to the currents, or in at least one of said zones of the screen may be displayed in succession the images relating to the combinations of said data and/or of said maps and/or of said images. In this implementing mode it is possible to allow the user to modify the settings determined automatically by the control unit.

A perfectly automatic mode provides that the user sets a governing condition, such as maneuvering navigation or cruising navigation or maintaining of the vessel in a predetermined position and with the bow oriented in a predetermined direction, that is with the median longitudinal axis of the vessel oriented according to a predetermined compass angle, and/or the advancement of the vessel along a predetermined trajectory having a predetermined linear or curved shape and a predetermined direction and with the bow oriented in a predetermined direction, while the control unit generates the command signals of the steering actuators and/or of the actuators of switching of the gear condition and of neutral and/or of the actuators of regulation of the number of revolutions as a function of the signals acquired from said combination of one or more sensors and/or from the data obtained from the nautical maps, meteo-marine maps and current maps and/or from the image processing of one or more cameras and/or other detection systems such as LIDAR or the like so as to govern the vessel as set by the user.

In the maneuvering condition and in particular of docking to a stationary reference, such as for example in the case of a mooring, the images of said one or more cameras may be processed for the determination of the position of the vessel relative to the stationary reference, for example the mooring quay and/or other stationary or floating obstacles present, and thanks to this information the control unit provides to execute the correction maneuvers of the displacement and/or of stable maintaining of the vessel in a predetermined position, in particular thanks to the governing method described above and which allows translations of the vessel according to any direction relative to the longitudinal axis thereof, in particular translations in transversal direction to said longitudinal axis.

According to a possible variant, when a plurality of cameras and/or other detection systems such as for example LIDAR systems are provided, it is also possible to generate a top view.

Still according to a possible variant which may be provided in any combination with one or more of the previous variant embodiments, it is possible that the vessel is provided along its perimeter with a plurality of proximity sensors which detect the distance from obstacles close thereto.

According to a further characteristic, the completely automatic mode may be automatically switched into manual mode according to one or more of the embodiments described above when the joystick is actuated or optionally any other manual command member.

It is possible to provide presence sensors of signals generated by manual command members, which activate and deactivate the automatic governing function according to one or more of the described variants and activate the manual command function of the system when the presence of a signal coming from one or more of said manual setting members of a target displacement of the vessel is detected. In combination it is advantageously possible to provide a monitoring function which detects the presence of said one or more manual setting signals in a predetermined time window which starts at the time of the automatic switching between automatic mode and manual mode and which, in absence of manual setting signals at the end of said time window, reactivates automatically the automatic command or governing mode.

Even if not illustrated in detail it is possible that the propulsion is not of the propeller type, but a variant embodiment may provide a jet propulsion having a single emission mouth of the propulsion jet.

FIG. 3 shows an exemplary embodiment, non-limiting of a possible system of implementation of the method according to the present invention which allows both the manual functionality and the automatic one and the implementation of any of the above listed governing conditions of the vessel.

Analogously to what described above, the vessel according to the example of FIG. 3 comprises a system of control of the movement and of the position of the vessel, which control system comprises at least a dynamic detection apparatus of the roto-translation adapted to the real-time measurement of the translation and/or of the three-dimensional rotation motions of the single members of the vessel and/or of the vessel itself and provided with at least one central control unit with a processing unit which executes at least one program comprising the instructions to interpret one or more setting signals generated by one or more sensors automatically or else generated by the manual actuation of one or more manual setting members of the target displacement of the vessel.

Said control program comprises the instructions to execute a control algorithm adapted to generate one or more control signals of one or more actuators.

In one embodiment, the result of the processing is made available for consultation to the operator, for example using said result as a signal of generation of indications of trajectory corrections, course, number of revolutions and/or gear direction of the engines and/or steering directions of the engines. In this case the corrections are applied manually by the user by means of one or more command members.

Said embodiment may be alternative or combined with any of the further embodiments which provide automated interventions of correction of the command signals of the actuators of setting of the parameters which define the operative conditions of the propulsion engines and/or of the bow-thruster and/or of the stern-thruster and which have been generated as a function of one or more setting signals generated by one or more manual setting members and/or as a function of the measurement signals of one or more sensors.

In particular, a man-machine interface is provided with a display on which are visualized the correction indications, in the form, for example, of arrow segments, the number of segments indicating the number of revolutions to be set and the direction of the arrows indicating the steering direction, while said indications are shown both in condition of manual correction and in condition of automatic correction.

In one embodiment, said central processing unit is, therefore, also put in communication with the setting members of the target displacement configured according to one or more of the embodiments described above and with the outputs of one or more of said sensors.

In one embodiment the data relating to the setting signals generated manually and to the corresponding settings of the functional parameters of said one or more actuators may be analyzed by an auxiliary program for manual governing, which program contains the instructions for the processing unit of execution of a verification on the congruity of the effect generated by said setting signals on the vessel also on the basis of one or more of the state and motion parameters of the vessel acquired by means of the combination of sensors and/or of the data detected from nautical maps, meteo-marine maps, current maps, image processing of one or more cameras or signals of inertial platforms, and on the basis of which congruity analysis the control unit may generate signals of non-conformity of the commands or of congruity of the commands with the desired governing effects or, in emergency and danger conditions, directly assumes the automatic control.

To contribute to the governing of the vessel there may be present further devices such as a GPS sensor and/or other position sensors such as gyroscopes, compass, radar, sonar, radio beacons, as well as signals coming from camera systems and/or other detection systems such as LIDAR systems or the like, possibly also installed on flying platforms or drones, all or in part interfaced with the processing unit of the control unit.

Among other advantages consequent to the use of inertial platforms applied to the actuators for the setting of the steering angle of one or of both of the engines there is the possibility of determining in a continuous way the orientation of the respective engine and/or of the respective propeller in a reference system integral with the vessel, also with regard to the tilt angle, that is the inclination of said apparatuses with respect to the drift axis of the craft. This adds a degree of knowledge of the dynamic state of the directional members usable by the control unit to improve the general functioning of the governing system as a whole and/or in specific situations such as for example steering cylinders with variable tilt as a function of the steering angle.

In a further embodiment, inspired by what has already been said above and which does not preclude nor limit other possible embodiments, there is made available an additional man-machine interface realizable by means of at least one unit capable of visualizing and/or providing sound indications, possibly vocal, to warn the operator of how the processing unit of the control unit for the generation of the command signals of one or more actuators is setting the angulation of the engines/rudders and/or the speed/direction of rotation of the propellers as well as of how the vessel is positioning itself as a function of said settings.

In the example of FIG. 3, the governing system of vessels, boats or the like object of the present invention comprises a direction command system, a system of command of variation of the speed of the two propulsion engines 2 or 4 which may be realized according to one of the variants provided in FIG. 1 or 2, and a control unit 8 which comprises a central processing unit for the generation of the command signals as a function of the setting signals of one or more manual setting members of one or more operative conditions which define a target displacement of the vessel. Said setting members are indicated with reference numbers 301, 302, 303. The control unit 8 and/or the processing unit may be configured to generate command signals of one or more actuators as a function of setting signals corresponding to measurement signals of one or more sensors. Said command signals may be generated as a function of the measurement signals of one or more sensors automatically and one or more of said command signals may be applied to one or more actuators alternatively or in combination with one or more of the command signals of one or more actuators generated by said control unit 8 as a function of setting signals provided by the actuation of one or more of said manual setting members.

In particular the direction command system comprises at least one directional command member 301, such as for example a steering wheel, a helm wheel or a tiller, a member 302 of variation of the number of revolutions of the propeller 201, 401 of each of the two propulsion engines 2 or 4 and/or of the propeller of the bow-thruster 6 and/or of the stern-thruster 6′ when provided, such as, for example, a lever, and the functions of said members 301 and 302 may be combined, in whole or in part, in other members of generation of the setting signals such as for example a joystick 303 and/or an advanced interface such as for example a device with graphical interface and touch screen 312.

Said graphical interface devices may also be provided with reference to one or more of the embodiments, of the variant embodiments and/or of the characteristics described with reference to the embodiments of FIGS. 1 and 2.

In the case of devices with graphical interface, such as for example the touch screen 312 but also other implementing forms, such as could be software programs running on handheld devices, there is provided a graphical processing unit 311 cooperating with the control system in order to provide to the operator visual and/or acoustic indications and/or verbal warnings, on the real-time position of the vessel in navigation, stationing and also during docking operations. The directional setting member 301 activates the central control unit 8 to the generation of directional command signals 340 aimed at setting a steering angle of one or of both of said steerable propulsion engines 2 and 4 as described in the example of FIGS. 1 and 2.

The member of setting or of variation of the number of revolutions of the propeller of one or of both of the steerable engines 2 and 4 and/or of the propeller of the bow-thruster and/or of the stern-thruster activates said central control unit 8 to the generation of command signals of regulation or of variation of said number of revolutions for one or both of said propulsion engines 2 and 4 and/or for the bow-thruster 6 and/or for the stern-thruster 6′.

In the setting members 302 there may also be combined switching commands of the direction of rotation of the propeller of one or of both of the propulsion engines 2 or 4 and/or of the bow-thruster 6 and/or of the stern-thruster 6′.

The setting members 301 and 302 may operate in combination or alternatively to the members 303 and 312 and therefore allow the governing of the vessel according to what is described with reference to one or more of the embodiments and/or variant embodiments and/or of the characteristics of the invention described previously and of those which will be described subsequently, in particular with reference to FIGS. 5 and 6.

Document EP4368492A1 describes in detail a possible implementation form of a governing system according to the present invention and this description is to be considered part of the present description.

The steering of each of the two propulsion engines 2 and 4 may take place by using devices comprising at least one steering actuator with single-action or double-action hydraulic cylinders or similar apparatuses actuated by a pressurized fluid within a hydraulic circuit; said steering actuator is by its intrinsic nature composed of one or more moving parts whose actuation entails, for example by means of one or more mechanical leverage systems, a controlled action on the orientation of the engines, and the use of a dynamic detection system of roto-translation 309 which could be one or a set of inertial platforms 310 which are positioned integrally with the moving members of the steering actuator allow to detect the change of position thereof and provide data which may support the functioning of the control algorithm executed by the processing unit of the control unit 8.

The use of the inertial platforms 310 or more in general of the dynamic detection system of roto-translation 309 must not however be seen in exclusive combination with the steering actuators, but it is possible the positioning thereof also in other positions of the vessel such as, by way of example and for graphical convenience, in the bow of the vessel itself possibly in solidarity with the hull.

As anticipated, the control of the governing system of the vessel object of the invention is executed by the processing unit 308 of the control unit 8 which on the basis of a control program executed by the same processes one or more setting signals of operative conditions of one or both of the propulsion engines and/or of the bow-thruster and/or of the stern-thruster for the obtaining of a target displacement of the vessel, from which it generates by means of said processing command signals of one or more actuators of setting and/or variation and/or regulation of one or more of said parameters which define said operative conditions of one or both of the propulsion engines and/or of the bow-thruster and/or of the stern-thruster functional to the obtaining of the target displacement of the vessel.

The command signals generated by said control unit are provided, that is applied, to the corresponding one or more actuators by means of connection interfaces between said control unit 8 and said one or more actuators.

Analogously and optionally, said control unit comprises communication interfaces with one or more sensors such as anemometers 313, position sensors such as for example GPS or GLONASS systems 314, or the like, position sensors by triangulation of radio signals of stationary coastal references and/or proximity sensors, magnetic and the like indicated overall by the icon 315, transceiver systems 316 and/or systems of acquisition and processing of video images 317, and in combination with which may be provided an optional secondary unit of processing of the acquired images for advanced detection, in real time, of the context in which the vessel is navigating and of the variation thereof in the image frames such as for example motion detection units, pattern recognition, thermal and/or infrared vision as well as the use of radio-controlled cameras and equipped on drone associated to the vessel.

In a variant embodiment, the camera systems may be configured to detect the presence of stationary and non-stationary floating obstacles such as for example buoys, floating debris or the like and also the distance of the vessel from them.

In addition or alternatively to the camera systems the vessel may also be provided with remote sensing systems of the LIDAR type or the like.

As mentioned, the processing unit of the command signals of said control unit 8 is also responsible for the execution of the control algorithm, which may be realized in different variants according to the specific implementation which is defined from time to time by the skilled technician also as a function of the type of vessel and/or of the number and/or type of control signals present as on-board equipment and of the combination of one or more sensors according to one or more types of said sensors and of the physical quantities measured thereby. Said implementation, which is foreseen to be variable also in progress for example by means of software update, may provide different operating scenarios, always referable to a logic of assisted control of the vessel; an example of implementation, non-exhaustive although considered significant, concerns the logical sequence provided by the method according to the present invention described previously and which provides for the translation of the vessel along a trajectory having a predetermined orientation different from that of the longitudinal axis of the vessel, that is the transversal or perpendicular translation to said axis in the docking phase and/or for the maintaining of the vessel in a stable position even in absence of an anchorage.

FIG. 4 shows a flow diagram of the method for the transversal translation of the vessel both in the docking phase such as the approach to a quay or to other vessels and for the maintaining of a predetermined position in absence of a physical anchorage to the seabed and/or also in presence of said physical anchorage in order to counteract displacement actions of the vessel imposed by wave motion and/or by currents and/or by wind.

Starting from a situation of stillness, that is with system non-operative but active and awaiting actions from the operator (blocks A and B), upon the selection of the navigation mode here defined “DOCKING” among the various options which the system may present (Block C) there is executed a preventive verification on the operative state of the actuators such as for example the actuators of steering, and/or of switching forward gear, reverse gear and neutral and/or of regulation of the number of revolutions for one or both of said propulsion engines 2 and 4 steerable and/or also of the actuators of actuation of the bow-thruster 6 and/or of an optional stern-thruster 6′ and/or the actuators of setting of the direction of rotation of the propellers and/or the actuators of regulation of the number of revolutions of the propellers of said bow-thruster and/or of said stern-thruster. This step is executed in order to read the position of a steering wheel, or the like and/or of a lever of setting of the direction of rotation and/or of the number of revolutions of one or both of said propulsion engines and/or of the bow-thruster and/or of the stern-thruster and/or the tilt position and the tilt angle with respect to a neutral vertical position of the lever of a joystick and/or the rotation angle around its longitudinal axis of the lever of said joystick and/or also of other optional setting members used by the pilot (block D); if it is determined that the operator does not require action by acting on said setting members (block E) the verification of the intention of terminating the operations (block X) and the presentation to the user of acoustic and/or visual signals by way of the man-machine interface (blocks Y and Z) is executed.

In the case where an automatic control and not a manual control is provided, the algorithm begins the execution of all or part of the checks aimed at defining the context in which the vessel is located and at setting a particular governing mode of the vessel, such as for example docking maneuver, position keeping with or without anchoring to the seabed, governing in cruising condition.

In particular, the checks are executed as a function of the signals supplied by the combination of one or more sensors or information sources as listed above in the preceding description and such as, for example and not exhaustively, the position of the vessel, the presence of fixed and/or moving obstacles, the distances of the vessel from said obstacles (block F), and the boundary conditions among which it is considered necessary to cite, without limitation, the meteo-marine conditions and in particular the speed, direction and gusts of wind, the condition of the wave motion and the inclination of the vessel, by means of one or more suitable onboard sensors (block G), the presence of currents, all of which are presented to the operator by means of one or more man-machine interfaces (block H).

Block I encloses the processing functions of the algorithm executed by the central unit of a control unit and aimed at defining the command signals of one or more actuators provided for setting the operative conditions of one or both propulsion engines and/or of the bow-thruster and/or of the stern-thruster (block J).

In an embodiment which may be provided in combination with one or more of the embodiments and variant embodiments described above, said actuators may be constituted by moving actuators which may be of any type such as mechanical, hydraulic, pneumatic, electric, electromechanical, electrohydraulic, magnetic or the like, and said actuators may be equipped on their moving part of the actuation system with one or more IMUs having the function of detecting translational and/or rotational motions and/or the orientation of the members to which they are coupled; the reading of this information (block K) may be part, but not essential for the invention, of the input signals forming part of the vessel governing method also by way of the comparison between said information coming from the IMUs and the desired movement set by the operator by means of said one or more setting members of the target displacement of the vessel and/or by means of one or more setting signals generated automatically by the control unit as a function of the signals received from one or more sensors (block L).

From the comparison between the set motion and the resulting motion consequent to the activation of the propulsion and/or steering members (block M), the algorithm define the effectiveness of the control signals previously calculated and, in the case where an insufficient level of action is determined, that is if the translation or rotation of the vessel or the maintaining of a preset position or orientation were not deemed consistent with what was expected by the operator, a series of verifications and/or adjustments (block N) will be executed, possibly repeated and/or optionally also according to self-learning logics, aimed at improving the accuracy resulting from the calculations carried out by the control algorithm (block I); in the case where the verifications at blocks L and M demonstrated the correct action of the governing systems, the control algorithm would be reiterated until the time of the end of operations (block X) set by the operator.

The figure and flow chart shown as an exemplary embodiment show, for simplicity, only one among the multiple examples of implementing forms which may be reduced or extended, possibly providing further sensors and/or operative sequences, and it is considered that such possible alternative implementations are sufficiently described by combining the specific embodiment described above as an example with the average skill of the person skilled in the art.

In particular, the control algorithm may be flanked by a control program which comprises, in the form of preconfigured and pre-programmed routines, that is routines comprising a set of instructions for the combined execution of different steering functions of one or both propulsion engines and/or of different modes of variation of the gear direction and/or of the setting of the neutral condition and/or of the number of revolutions of one or both propulsion engines and/or of the bow-thruster and/or of the stern-thruster according to one or more of the embodiments of the method described above.

For example, a command of translation of the vessel for a docking maneuver may automatically activate, thanks to the sole indication of the translation direction by means of a joystick, the setting of discordant, converging and/or diverging steering directions of the two engines with preset parameters or preset ranges of said parameters relating to the steering angles in the respective steering positions of said two engines, and/or relating to the driving direction or neutral condition and/or to the number of revolutions of one or both of said two propulsion engines and/or of the bow-thruster and/or of the optional stern-thruster.

In addition, said parameters or said ranges may be modified manually by the pilot or optionally automatically by the control unit on the basis of the status signals of the combination of one or more sensors according to one or more of the possible variants described above and of the comparison with a setting of the displacement condition of the vessel and/or of the maintaining of a position set by the pilot himself.

According to the present invention, in combination with any of the variant embodiments of the governing method and system described above, both in combination with a generation of manual setting signals of a target displacement of the vessel and in combination with an automatic generation of manual setting signals of a target displacement of the vessel executed alternatively to each other or in combination, the method provides an initial temporary phase, that is of limited and predefined duration, in which initial phase there is provided the increase or the decrease or the temporary inversion of one or more of the operative conditions of the bow-thruster and/or of the stern-thruster and/or of one or both of said engines with respect to the operative conditions correlated or defined with one or more of said setting signals and at the end of which initial temporary phase the operative conditions defined by said one or more setting signals are restored.

In an embodiment, the duration of said initial temporary phase and/or the increase or the decrease of the operative conditions of the bow-thruster and/or of the stern-thruster and/or of one or both propulsion engines with respect to those defined by the combination of setting commands is defined as a function of the contingent navigation conditions of the vessel and/or as a function of its mass, that is of the inertia of motion deriving from said mass.

In an embodiment, the duration of the initial temporary phase of application of said command or of a combination of said commands and/or the increase or decrease of the operative conditions set and defined by said command or by the combination of said commands is determined empirically by means of application of one or of a combination of said commands by means of manual setting members of a target displacement of the vessel which are univocally correlated with one or with a combination of said commands and verification of delays or differences of execution of the effective displacement of the vessel with respect to that defined by said at least one command or by said combination of commands, performing manual variations or corrections of compensation of the operative conditions defined by said command or by said combination of commands and applying said manual variations or corrections for a predefined period of time by means of said setting members, said variations and/or corrections and/or said predefined period of time being stored and used as determination of the duration of the initial temporary phase at the time of application of said command or of said combination of commands and for the determination of the increase of one or more of the operative conditions defined in one or in a combination of commands and applied automatically in said initial temporary phase.

When, as defined above, the operative conditions are represented by a combination of parameters which define the steering angle of each propulsion engine 2, 4 and/or the direction of rotation of the propeller and/or the number of revolutions of the engine or of the propeller of one or both propulsion engines and/or the direction of rotation of the engine and/or the number of revolutions of the engine or of the propeller of a bow-thruster and/or of a stern-thruster, in said initial phase the values of said parameters calculated on the basis of the manual setting commands or as a function of the measurement signals of one or more sensors are increased, and/or decreased and/or inverted in a predefined measure preset in the control unit 8, and said increased or decreased or inverted value is maintained for the entire predefined temporal duration of said initial phase.

Said initial temporary phase is triggered by the application of at least one command signal to at least one actuator or of one or more command signals to one or more actuators.

The temporal duration of said phase as well as the increase or the decrease of the values of the parameters which represent the operative conditions or the inversion of said operative conditions are also settable by the user.

Both the temporal duration of said initial phase and the measure of increase or decrease or inversion of one or more of said parameters are settable in an experimental calibration phase executed by the pilot at the time of the first start-up of the governing system, and the control unit comprises a memory for saving the duration of the initial temporary phase and the measures of decrease or increase of one or more of said parameters or of inversion of the operative conditions.

The temporal duration of the initial phase is measured by means of a timer which is associated to the control unit as a peripheral unit or which is in the form of a timing software executed by the same and which timer is regulated to the set duration and is activated at the counting of time at the time of application of one or more command signals to one or more actuators, generating an end command of the initial temporary phase when the set duration has elapsed and which command cancels the increase or the decrease or the inversion applied during said initial phase by applying to one or more actuators the corresponding command signal with the values defined as a function of the manual or automatic setting signals of the target displacement of the vessel.

FIG. 5 shows an example of a flow chart for the implementation of said temporary phase. Step 500 provides for the activation of the governing system. At step 510 one or more manual setting members of a target displacement of the vessel are actuated. Said setting signals are supplied to the control unit 8 and processed by its processing unit, so that as indicated at step 520 said control unit generates one or more command signals of one or more actuators for setting the operative conditions of the bow-thruster and/or of the stern-thruster and/or of one or both propulsion engines.

Said command signals are supplied to the corresponding actuators as indicated at step 530. At the same time, this action constitutes the trigger which initializes the initial temporary phase as indicated at step 531. The parameters which define the operative conditions as a function of the setting signals are selectively increased or decreased or inverted in the measure preset in a previous calibration step of the governing system. At the same time, the clock or the timer is also activated to monitor the duration set for said initial phase. Once said duration has elapsed, at step 532 it is provided to terminate the initial phase of increase/decrease/inversion of the operative conditions of said one or more actuators and to restore the command signals generated as a function of the setting signals.

As indicated at step 540, said restored command signals are applied until reaching the target displacement set at step 510. At step 550 a verification is carried out whether the control unit has generated further automatic command signals as a function of one or more sensors of detection of the operative conditions and/or of the displacement of the vessel and/or of other types of signals. In the affirmative case, step 560 of application of said command signals defined on the basis of the measurement signals of one or more sensors is executed. At step 570 it is verified whether the effective displacement of the vessel corresponds to that set. In the affirmative case, at step 580 it is verified whether new manual setting signals have been generated. If the answer is negative, the process terminates as indicated with 590. If the answer is positive, the system passes to the repeated execution of steps 510 to 580. If at step 550 the answer is negative, step 570 of verification is followed, whether the effective displacement corresponds to the set target displacement. When the verification step 570 is negative, step 540 is repeated, that is the restored command signals continue to be applied.

According to a further feature of the method according to the present invention, in combination with the temporary phase of increase/decrease/inversion described above, the control unit may execute a software which provides for setting a steering angle of one engine different from that of the other engine. This condition is shown in FIG. 2B, in which the engine 4 is steered with a certain steering angle represented by the orientation of the axis A4 with respect to the central axis. Engine 2 is instead shown in two different positions with respectively a steering angle different from that of engine 4 and which represented by the orientation of the axis A2 with respect to the longitudinal central axis of the vessel and by the axis A2′ may be a steering angle greater or lesser than that of engine 4. In this configuration the steering angles of the two engines are different from each other and asymmetric with respect to the central longitudinal axis of the vessel.

This mode of setting the steering angles is applied to further reduce the displacement speed of the vessel beyond the minimum value for this speed achievable with symmetric steering angles of the two propulsion engines 2 and 4 with respect to the central longitudinal axis of the vessel and with a number of revolutions of said two propulsion engines which is maintained at a minimum value, which cannot be further reduced.

The method according to the present invention provides to further reduce the displacement speed of the vessel by modifying the directional component of the propulsion thrust generated by one engine with respect to the other engine in such a way that said component opposes and contrasts the displacement of the vessel reducing its speed, when it is no longer permissible to reduce the number of revolutions of the engines.

Even this embodiment of the method may be implemented by means of a software which comprises the instructions for executing the aforesaid steps, in combination with interfaces for entering a minimum value for the number of revolutions of one or both propulsion engines and/or of the engines of the bow-thruster and/or of the stern-thruster and which, when executed by the control unit or by its processing unit, configures said control unit so that the same may execute the aforesaid steps.

In FIG. 6 there is shown a flow chart of the steps of this method according to an exemplary embodiment. At step 600 the governing system is activated. Step 610 provides for the actuation of one or more manual setting members of the target displacement of the vessel. At step 620 the generation of one or more command signals of one or more actuators of setting of the operative conditions of the bow-thruster and/or of the stern-thruster corresponding to said target displacement at low speed is executed.

At step 630 the command signals are applied to one or more actuators. Optionally, as indicated by step 631, it is possible to provide steps 531, 532 and 540 relating to the execution of an initial temporary phase of increase/decrease or inversion of the parameters which define the set operative conditions. This is indicated by showing step 631 with dashed lines.

Following step 630, there is provided a step 640 of detecting the effective displacement speed of the vessel and of comparison with the speed of the set target displacement. Verification at step 650 may be negative, in which case a verification at step 670 is executed whether the engine or engines already operate with a minimum allowed number of revolutions. If the answer is negative, the number of revolutions of one engine or of both is reduced as indicated at step 680 and steps 630 to 670 are repeated. When the answer to verification step 670 is affirmative, step 690 is executed which provides for the variation of the steering angle of only one engine with respect to the other (asymmetric steering angles of the two engines) to such a measure and in such a direction as to be functional to generate a component of the propulsion flow which contrasts the displacement. Following this step, step 630 is repeated, after which the effective speed of the vessel is measured repeating step 640 and step 650 of verification. If the verification is negative, the loops described above are repeated, while if the verification is positive, at step 660 it is verified whether the effective displacement of the vessel corresponds to that set. If negative, it returns to step 630, while if positive, a step 691 follows of verification whether new setting signals have been generated; if negative, the process terminates as indicated with 692, while if affirmative, the process returns to step 620 and is repeated as described above.

Although in the examples described and illustrated, the stern-thruster is always considered as an optional further device which is added to the bow-thruster, an embodiment of the invention instead provides that in place of the bow-thruster only said stern-thruster is provided, the presence of a bow-thruster being considered optional with respect to the stern-thruster. For the stern-thruster in replacement of the bow-thruster apply “mutatis mutandis” all the characteristics and/or embodiments and/or variant embodiments described above with reference to the exemplary embodiments which provide for the presence of only the bow-thruster.

Alternatively, the two engines may comprise propellers driven by rotation shafts fixed as to their orientation, while the steering action is exercised by a rudder blade provided for each propeller and in interfering position with the fluid flow generated by the same.

Furthermore, the method and system according to the present invention may also be applied in combination with vessels which comprise only one engine and/or a bow-thruster and/or a stern-thruster or more than two propulsion engines and/or a bow-thruster and/or a stern-thruster.