FIELD OF THE INVENTION

The invention relates to a control device and system for manoeuvring control of a marine vessel at low speed and, in some embodiments, also for control at cruising speeds.

BACKGROUND TO THE INVENTION A number of different control systems may be used to control die movement of a marine vessel that is propelled by one or more waterjet units. The direction and magnitude of the net d rust vector(s) produced by a waterjet(s) and therefore imposed on the vessel is a function of the angle of the steering deflector(s) or nozzle(s), the throtde setting of the engine(s) driving the waterjet(s), and the position of the reverse deflector(s). A helm wheel is commonly provided to control die posidon of die steering deflector(s) or nozzle(s). One or more control levers are provided to control the position of the waterjet(s) reverse duct(s) and the throtde setdng of the engine(s) driving the waterjet unit(s). A joystick control device or other control device may be incorporated into the control system of a waterjet vessel, particularly to provide an alternative means of control for low speed manoeuvring operations such as docking and getting underway. Bow and/ or stern thruster(s) may also be installed in a vessel to enhance manoeuvrability when docking and getting underway. The bow and/or stern thruster(s) may be controlled by a joystick or other control device referred to above or alternatively by a separate dedicated control, for example.

It is an object of the invention to provide an improved or at least alternative form of control device for control of a marine vessel.

SUMMARY OF THE INVENTION

In one aspect the invention broadly comprises a control system for a marine vessel comprising one or more waterjet units for propelling the vessel, the control system comprising:

a control device including a body and a disc-like control element positioned at one end of the body and rotatable about an axis substantially perpendicular to an adjacent upper surface of the body and exposed at said one end of the body so that the control element can be rotated by the fingers or fingers and thumb of a user's hand resting on said upper surface of the body with the user's fingers or finger(s) and thumb contacting an edge part of the control element; and a control system arranged to operate the waterjet unit(s) to steer a vessel responsive to rotation of die control element.

In another aspect the invention broadly comprises a control system for a marine vessel comprising one or more waterjet units for propelling the vessel, die control system comprising:

a control device including a body and a rotatable control element having at least an edge part of the control element exposed from the body, die body comprising an upper surface adjacent the control element on which a user's hand may rest with the axis of rotation of the control element passing through die user's hand and with die fingers or fingers and thumb of the user's hand contacting said edge part of the control element so that die control element can be rotated by the fingers or fingers and thumb of die user's hand; and

a control system arranged to operate the waterjet unit(s) to steer a vessel responsive to rotation of the control element. The edge part of the control element may extend beyond an edge part of die body and the fingers of a user's hand resting on said upper surface of the body can contact to rotate the control element by the curling over die exposed edge part of the control element.

Preferably die edge part of the control element is an annular or curved edge part, preferably an at least semi-circular edge part, and may be a greater than semicircular edge part.

Optionally the marine vessel may also comprise one or more lateral dirusters and the control system may be arranged to also operate the lateral thrusters(s) to steer or assist in steering or manoeuvring die vessel in accordance with the rotation of the control element.

In a preferred embodiment the control system is arranged to operate the waterjet unit(s), or the waterjet unit(s) and lateral thruster(s), so that the extent or angle of rotation of the control element, eidier clockwise or anticlockwise, determines a rate of corresponding yaw movement of the vessel (rotation of the vessel about a vertical axis) to starboard or port respectively.

In a preferred embodiment the control device is also responsive to pressure on a surface part of the device to cause the control system to operate the waterjet unit(s) or any lateral thrusters(s) or both to translate the vessel in a direction indicated by pressure on the control element by a user. In one such embodiment the control device may comprise pressure sensitive elements each associated with a particular direction. Pressure sensitive elements may be pressure sensors sensitive to the level of pressure applied, with die control system arranged so that the magnitude of the thrust vector generated is proportional to the level of pressure applied to die control element.

Alternatively pressure sensitive elements may be switches, with the control system arranged so that the magnitude of the thrust vector generated is fixed. In a further particular embodiment pressing on the control element multiple times in the desired direction may cause a switch to be operated multiple times with each such switch operation increasing die thrust vector magnitude in a step, up to a maximum thrust. In another embodiment die magnitude of thrust increase may be proportional to the length of time the switch is depressed or pressure is applied to a pressure sensor. The system may also be arranged so tiiat to reduce the trust vector magnitude, die switch associated with the opposite thrust vector can be depressed.

In anodier aspect the invention broadly comprises a control device for a marine vessel, comprising a body and a rotatable control element having at least an edge part of the control element exposed from die body, the body comprising an upper surface adjacent the control element on which a user's hand may rest with the axis of rotation of the control element passing dirough d e user's hand and widi the fingers or fingers and thumb of the user's hand contacting said edge part of die control element so that the control element can be rotated by the fingers or fingers and thumb of the user's hand to steer a vessel having a control system responsive to rotation of the control element.

In anodier aspect the invention broadly comprises a control device for a marine vessel, comprising a body and a disc-like control element positioned at one end of the body and rotatable about an axis substantially perpendicular to an adjacent upper surface of die body and exposed at said one end of the body so that the control element can be rotated by the fingers or fingers and thumb of a user's hand resting on said upper surface of the body with the user's fingers or finger(s) and thumb contacting an edge part of the control element so that the control element can be rotated by the fingers or fingers and diumb of the user's hand to steer a vessel having a control system responsive to rotation of the control element. The term 'comprising' as used in this specification and claims means 'consisting at least in part of, that is to say when interpreting statements in this specification and claims which include that term, the features, prefaced by that term in each statement, all need to be present but other features can also be present. In tins specification and die accompanying claims the term "vessel" is intended to include boats such as smaller pleasure runabouts and other boats, larger launches whether mono-hulls or multi- hulls, and larger ships. More generally, the control device of the invention may be suitable for any planing or displacement type vessels, regardless of their size, speed capabilities, and hull type. The control device can be used in such vessels while the vessel is negotiating at either zero speed, low speed (typically below 5 knots) or at higher speeds. It is beneficial at all speeds and particularly beneficial when the vessel is navigating at higher speed requiring accurate, quick and easy control by the user. In this specification the term "lateral thruster(s)" is intended to include thruster(s) mounted in the bow of the vessel (a bow thruster) which can apply dirust to port or starboard, and similar fixed diruster(s) provided elsewhere such as at the stern of the vessel, optionally which may be controllable to vary the magnitude of the dirust provided.

In this specification the term "waterjet" is intended to include a steering element to direct die water stream in a direction such that it steers the vessel to port or starboard while translating forwards (or reversing). The waterjet typically includes a reversing bucket which can be deployed into the water stream in a linear manner to reduce the forward d rust gradually to zero thrust, and to provide a gradually increasing reverse thrust vector for the vessel as the bucket is deployed further to its fully lowered extent. .

BRIEF DESCRIPTION OF THE DRAWINGS

A preferred form of the invention will be described by way of example only and with reference to the drawings, in which:

Figure 1 is a perspective view of one embodiment of a control device of the invention;

Figure 2 is a top view of the control device of Figure 1 ;

Figure 3 is a side view of the control device of Figures 1 and 2;

Figure 4 shows the control device in a user's hand;

Figure 5 shows the effects on a vessel of activation of pressure regions on the control device; Figure 6 is a perspective view of an alternative embodiment of a control device;

Figure 7 is a schematic diagram of a propulsion and control system comprising twin waterjet units of a marine vessel; Figure 8 shows a number of fundamental manoeuvres which are possible with the system of Figure 7;

Figure 9 shows a sideways manoeuvre to port for the twin waterjet unit shown in Figure 7;

Figure 10 is a schematic diagram of a propulsion and control system comprising a single waterjet unit, and a bow thruster, of a marine vessel; and

Figure 1 1 shows a number of fundamental manoeuvres which are possible with the system of Figure 10.

DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS

Referring to Figures 1 - 3, an embodiment of a control device 1 comprises a main body 2 of a size and shape enabling it to be conveniendy handheld and which supports a rotatable steering control element 3. The control element 3 is positioned at one end of the main body 2 and is rotatable clockwise or anticlockwise, about an axis R substantially perpendicular to the main body 2 (see particularly Figure 3). The control element 3 has a full annular (360°) peripheral shape, but may alternatively have a half or part annular or other curved shape (e.g. 270° or 180°), widi an edge 3a which is exposed at and preferably protrudes from the end of the main body 2.

The control device 1 is shaped to enable a user operating the device to hold it in one hand or at least to place their hand on top of the device 1. In either case, the device enables die user to curl one or more fingers or finger(s) and thumb over the exposed edge 3a of the control element 3 in a natural position as shown in Figure 4, so that the user can rotate the annular control element by movement of the users finger(s) or finger(s) and thumb. A centre part of the control element 3 may have a flat or alternatively for example a slighdy domed or concave top surface 6 which may or may not rotate with the annular control element 3, as will be further described.

The control device provides steering command signals to the control system for the vessel's propulsion unit(s) and/or any lateral thruster(s), to steer the vessel in accordance with rotation of the control element 3. In particular, die control system operates the vessel's steering

nozzles/deflectors, and optionally also propulsion unit(s) and/or lateral thruster(s), so that rotation of the control element 3, clockwise or anticlockwise, about its axis causes a corresponding yaw movement of the vessel.

The control device 1 may comprise a rotary potentiometer provided within the casing of the control device, which optionally may be provided with limiting stops which restrict rotational movement of the control element 3 to a predetermined angular range. Alternatively, rotation of the control element 3 may be sensed by a hall sensing system provided in the control device 1 , to provide an output control signal indicative of the angle of rotation in the form of an analogue voltage as a function of that angle. A hall sensing system can be arranged such that dual redundant sensing can be provided giving two analogue output voltages for each angle of rotation. The control signal may also be provided in digital form from the hall sensing circuit. A benefit of a hall sensor is that the magnetic field is sensed providing contact-less sensing and allowing a full waterproof seal to be easily achieved. Alternatively again the control device may generate a pulse train as die control element 3 is rotated about its axis at certain angle increments, representing a predetermined angle change. Port and starboard turning demand can be recognised by different digital signals. No end stops may then be necessary due to the angle of the element 3 not providing the steering demand as an absolute angle. Other mechanical, electrical and/ or electronic arrangements may be utilised to sense die angle of the control element 3 relative to a neutral position in which die control device commands zero heading angle demand (or the direcdy ahead demand position), to diereby generate steering control signals.

The neutral position of the control element 3 may be indicated by a detent at the neutral position, or a feature on element 3 that indicates a neutral position via touch, for example. In response to steering command signals from the control device, the control system operates the vessel's steering nozzles/deflectors and optionally also propulsion unit(s) and/or any lateral diruster(s) to cause the vessel to yaw in accordance with the angle of the control element 3 or change of angle of the control element. In particular, the vessel's rate of turning is determined by die rotational position of the control element 3 relative to the neutral position of die control element 3. For example, if the operator wants to alter the vessel's demanded heading while underway the operator applies rotation to the control element 3, clockwise or anticlockwise, in the appropriate direction about the axis R. The greater die angle of rotational displacement of the control element 3 from its neutral position, the greater the vessel's rate of turn or yaw.

Additionally or alternatively to movement of the control element 3 causing the vessel steering nozzles/deflectors to move, and optionally also propulsion units and/or any lateral thrusters to operate, move to cause die vessel to yaw as commanded, movement of the control element may in a multi-jet vessel optionally cause the inside reverse deflector or reverse bucket to drop partially, and/or an outside propulsion unit to increase thrust or an inside propulsion unit to decrease thrust, to cause a steering effect on the vessel. Optionally, at or towards limits of port and starboard movement of the control element, the resistance provided by a spring mechanism, against the pressure of which the operator moves the control element 3, may increase, by use of one or more variable rate spring mechanisms for example, or any other suitable arrangement. During a first and typically greater part of the range of movement of the control element 3 away from its natural position, the operator moves the control element 3 against a lesser level of spring pressure and then in a second and typically lesser part of the movement (towards the maximum extent of movement of the control element 3) the bias against which the operator must move the control element 3 increases. At the same time the control system is arranged to cause the rate of movement or turn of the vessel to increase more rapidly during the second part of movement of die control element 3. Alternatively, a small electric actuator or motor within the device may be arranged to provide increasing resistance as die rotational element 3 rotated away from its neutral position. Such force feedback is often referred to as haptic feedback. In other embodiments an alternative mechanism or system may be used to provide movement of the control element 3 with a friction feel, with the level of friction perceived by die user optionally also being user-adjustable. In yet another alternative embodiment, a mechanism may be provided to give movement of the control element 3 a soft ratchet feel.

Different embodiments of the control device 1 may allow the device to be mounted on or incorporated in locations including: the end of d e left or right arm of a seat, the bridge console of the vessel, the wing station, the flying bridge, or the aft station. The control device 1 can either be permanendy attached to die arm rest, bridge console or wing station or aft station or it can be detachable from a mounted location and used as a remote device. Where detachable, a lanyard may be provided between the device 1 and a fixed point, which can be released when pulled with some force. Upon release a control signal may automatically be sent to the control system to initiate reduction of engine throtde(s) to idle and alter the position of the reverse bucket(s) to produce zero net thrust for the vessel for example.

There may be additional control input or inputs such as one or more buttons 5 or other control elements for control of engine throtde and/or the reverse deflector(s) of the propulsion units. For example referring to Figures 1 and 2 push buttons 5a and 5b may act as plus and minus controls for adjusting the engine dirotde. These may be located on the main body 2 of the device 1 to sustain single handed operation of the control device 1. Additionally, there may be buttons or sliding elements or rotary elements for adjusting other vessel systems such as a vessel's interceptors (if fitted) or nozzle trim on the waterjets (if fitted). A button 5a or a different button or device may be provided to assert control of the yaw movement of the vessel using the control device primarily when the vessel in at higher speeds (cruise speeds). A button 5b or other button or device may be provided to assert control of die vessel when low speed or docking control is required by the user. Such buttons are provided to allow the user to assert control over other control devices that may be in the control system and indicate the type of control required (low speed docking or higher speed cruise).

In the preferred embodiment of Figures 1-3 the control device 1 also comprises a pressure sensing system (not shown) responsive to manual pressure on the upper surface 6 of a centre part of control element 3 to control operation of the waterjet(s) and/or any lateral dirusters(s) to translate (rather than steer) the vessel during low speed manoeuvring. In this embodiment die upper surface 6 of the device does not rotate with the control element 3. Mounted underneath surface 6 are pressure sensitive elements such as strain gauges or similar pressure sensing devices, or alternatively switches that activate when pressure is applied. In the preferred form, the pressure sensitive elements are mounted proximate to the periphery (or edge) of surface 6 at the top, bottom, left and right regions of die surface 6. Pressure can be applied by the user at or between these regions to indicate a desired direction of thrust (i.e. desired thrust vector). Activation of a pressure sensitive element or elements results in a thrust command signal being sent to die control system which in turn operates the appropriate waterjet unit(s), steering nozzle(s)/deflector(s) and/or any lateral thruster(s) to translate the vessel in the desired direction and widi the desired level of thrust. For example (witii die control element 3 in the neutral position commanding an ahead compass heading), pressure applied by the operator of the device 1 at die top region of surface 6 (i.e. the " 12 o'clock position") will cause the vessel to translate/ surge ahead. Similarly pressure applied to the left ("9 o'clock position"), right ("3 o'clock position") and bottom ("6 o'clock position") regions of surface 6 causes the control system to activate the required waterjet unit(s), nozzles/deflectors and/or any lateral thrusters(s) to effect translation of the vessel to port, to starboard, and astern respectively. Applying pressure to surface 6 in between two adjacent regions of die four pressure regions commands a combination of the above translations. For example, pressure applied in between the top and left regions of surface 6 activates the pressure sensitive elements associated with the top and left regions respectively, causing the vessel to translate diagonally ahead and to port. .

Figures 5a)-h) show a series of examples of pressure application to surface 6 (while the steering control element 3 is in the neutral ahead position) and the resulting movement of vessel 20. In each case the point at which user pressure is applied is indicated by a bold point 10. The (direction of the) thrust vectors acting on vessel 20 as a result of activation of die associated pressure sensitive element(s) is shown by a single headed arrow 25 in each case. When the control element 3 is rotated the vessel will rotate as described above. If at the same time, pressure is applied to the surface 6 of the device, translation of the vessel will also occur, at die same time. Also, in Figure 5 element 3 on the left hand of each figure is shown with a thrust control element 7 (described in detail below) and element 3 on the right is shown without this.

In an alternative embodiment, an array of a greater number of pressure sensors may be arranged about the periphery of the surface 6 to provide more resolution/greater direction control. In either embodiment the pressure sensitive elements may be located in the base of the device 1 attached to a shaft or bearing surfaces appropriately positioned to sense a degree of downward pressure and location on the surface 6.

In embodiments in which switches are employed as the pressure sensitive elements, activation of a switch is arranged to provide an increase/decrease in the magnitude of the associated thrust vector by a pre-set amount (i.e. a step response). Alternatively, if pressure sensors are employed as the pressure sensitive elements, the magnitude of the associated thrust vector may be proportional to the level of pressure (i.e. force) applied by the user of the device 1. In each of these two embodiments, the level of change in thrust may be pre-programmed into the control system. For the switch embodiment each of a series of switch activations (i.e. each switch press) may increase or cause a gain in dirust in the direction associated with that switch, by a predetermined amount. For the pressure sensor embodiment each unit of pressure applied may correspond to a pre-stored gain in thrust in the direction associated with that sensor.

The control system may, for example, have a microprocessor, microcontroller, programmable logic controller (PLC) or the like, which is programmed to receive and process steering command and thrust command signals generated by rotation of die control element 3 and pressure on the surface 6, and send control signals to the vessel's steering nozzles/deflectors and optionally propulsion unit(s) and/or any lateral thruster(s) to steer the vessel, and send control signals to the vessel's steering nozzles/deflectors, propulsion unit(s) and/or any lateral thruster(s) to translate the vessel, as commanded. The control system can be pre-loaded with data pertaining to the type and number of propulsion unit(s) and lateral thruster(s) (if any) onboard and can be pre-programmed to operate the or each propulsion unit and lateral thruster(s) in combination or alone to manoem ^r re the vessel in accordance with the operation of the control device 1. Referring again to Figures 1 - 3, the control device 1 may furtiier comprise a manually operable dirust control element 7 in the form of a thumbwheel 7 having an axis of rotation substantially perpendicular to that of control element 3 (i.e. perpendicular to axis R in fig 3) and embedded substantially at die centre of control element 3 to enable the user to easily operate the wheel 7 using their thumb (or any odier finger). The diumbwheel 7 may be arranged to control various parameters and settings relating to the way in which die control system operates die vessel's propulsion units during low (or high) speed manoeuvring.

In particular, thumbwheel 7 may be arranged as a dirust control element for controlling the level of thrust (or gain in thrust) demanded in response to pressure applied to the pressure sensing mechanism and/or in response to manipulation of the control element 3. Thumbwheel 7 may provide the user widi die ability to control engine tkrotde (and/or the reversing bucket) and/or die bow tiiruster demand and the degree of change or gain in thrust associated with activation of a pressure sensitive element (i.e. enables alteration of die pre-stored gain in thrust). For the switch embodiment tins corresponds to the level of gain in dirust (in the desired direction) each time a switch is activated. For the pressure sensor embodiment this corresponds to the gain factor associated with each unit of pressure applied by die user. The thumbwheel 7 may also be operated to control the relationship between rotation of the control element 3 widi respect to die neutral position and the level of thrust demanded and hence the rate of vessel rotation being demanded. By way of example, the position of the diumbwheel 7 may determine die thrust demand for each degree of rotation of die control element 3 and thereby provide the user with a means of setting die upper or maximum speeds attainable during a low speed docking manoeuvre.

In the case where switches are used within the device, a means may be provided to zero. die previously applied thrust by activating a switch on die device. The switch may be associated with the tiiumb wheel element 7, so that by the user applying downward pressure on the wheel 7, or alternatively simply on the centre of the control element 3, the switch is activated to zero the thrust vector. Thumb wheel 7 may alternatively be for example, be a slider having a slidably adjustable tab (or similar) for altering the level of thrust. Alternatively again the system may be arranged such that when in cruise mode, pressure on the surface 6 in die 12 o'clock position increases thrust and pressure on the surface 6 in the 6 o'clock position decreases thrust. Thrust control element 7 need not necessarily be provided on the surface 6. It may be conveniendy located at any other position on the body 2 of the control device 1.

Rotation of the control element 7 may be sensed by for example an absolute position device such as a potentiometer or a digitising position (or rotary) encoder, or by a hall sensing system as referred to previously.

Control systems comprising a control device as described may control one or other or both of:

1. Manoeuvring e.g. docking (or slow speed) mode, where the vessel is typically moving at a speed of 5 knots or below, and

2. Cruise mode, where the vessel is typically travelling at 5 knots or more.

Where a control system is arranged to control both manoeuvring and cruise mode, a button or button(s) 5, for example, on the device 1 may be used to switch between the two modes of operation. For example, buttons 5a and 5b (shown in figures 1 and 2) on the device 1 may be used for this purpose. Alternatively, die control system may determine the vessel speed (via GPS for example) and automatically switch between the modes of operation.

In this preferred form, when the vessel is travelling in cruise mode, the pressure sensing mechanism associated widi die surface 6 of die device may be disabled while the control system remains responsive to rotation of the control element 3 for steering the vessel. Thrust control element 7 if provided may also still be enabled for adjustment of the level of desired engine RPM and in addition or alternatively the bucket position in the particular direction of thrust of the waterjet. Alternatively pressure on the top or bottom of surface 6 (12 o'clock and 6 o'clock) may be arranged to increase or decrease the level of forward dirust accordingly and/or to provide forward and aft (reversing) vessel thrust while in cruise mode.

In the embodiments described above the vessel's rate of turning is determined by the rotational position of the control element 3 relative to its neutral position - the greater the angle of rotational displacement of the control element 3 from its neutral position, the greater the vessel's rate of turn or yaw. In an alternative embodiment the control element may be rotatable to port or starboard to a fixed or lesser extent, and a force sensor based system may be provided associated with the control element 3 so that the vessel's rate of turning is proportional to the force applied on the control element to port or starboard (against port or starboard force sensors for example). The higher the force applied by die operator to the control element 3 to port or starboard, the greater the commanded rate of turn to port or starboard.

In a further embodiment the control element 3 may act as an absolute heading control. For example compass headings or degrees may be marked adjacent the control element 3, wholly or pardy around its external periphery or around the edge of the surface 6 within the control element 3. The control system of the vessel may be arranged to monitor die actual vessel heading via the GPS, a gyro compass or other absolute heading indication device, and maintain the vessel on the heading commanded by die operator via die position of die control ring.

In a number of odier embodiments, control device 1 may also include any combination of the following additional buttons and features to enhance usability of the device:

• Gearbox buttons that will engage and disengage the gearbox. This may include various gear ratio buttons and reverse control functionality.

• Gearbox status indication, and in particular which gear has been engaged.

• Indicators (such as LEDs) that indicate the steering demanded by the user and the steering nozzle/deflector position achieved.

• A detent diat provides the user with positive feedback on the direcdy ahead position for steering control. The amount of detent may be adjustable from zero to maximum.

• The device may provide feedback to the user when dangerous vessel manoeuvres are being demanded by the user (e.g. vessel spinout).

• A physical indication on the device's control element 3 diat the user can feel to indicate the ahead position. This could be a protrusion on a fixed outer surface of the device proximate to the exposed edge 3a of the control element 3 for allowing the operator to feel die degree of rotational displacement of control element 3 from the direcdy ahead neutral position.

• An alternative means for rotating the control element 3 such as a dimple 4 provided on the top surface 6 of the control element 3 as shown in figure 6.

• The thrust control element 7 on the device 1 may include an indication on it to provide feedback to the user of the neutral (bucket) and/or idle position (engine).

• The thrust control element 7 on the device 1 may include a detent indicating the neutral position to the user.

• The device 1 may provide audio feedback to the user when the thrust control element 7 has achieved neutral position. The thrust control element 7 on the device 1 may include a ratchet system to provide a tactile feel when die element 7 is being adjusted

The device 1 may include a sound feedback device that provides various system status messages for example when the gearbox(s) state has changed or when the thrust demand has reached neutral. It may also indicate when the device has switched between cruise mode to docking mode. Furthermore, a system alarm and warning indications may be employed. The device 1 may also provide audio feedback to die user when the detent position has been reached on the device's control element 3 and/ or on die thrust control element 7.

The device 1 may include items to control other vessel systems such as interceptor or ride control systems.

The device 1 may include manual controls for the control of the waterjet trim nozzles. The device 1 may include manual control of bow thrusters.

The device 1 may include a sensor system that determines the orientation of the device in relation to the vessel's bow and stern. As die orientation of die device changes between facing ahead and facing astern, the control system would automatically invert die functionality of the appropriate inputs on the device to enable an operator of the device to adjust the level of thrust and manoeuvre die vessel in accordance with the way they are facing. This removes the need to factor in the change in orientation of the device when the operator moves to face the odier end of the ship. For example, as die operator moves die device from facing ahead to facing astern, the device switches mode so the inputs associated witii the vessel's stern become those associated with the vessel's bow and vice versa and the inputs associated with the vessel's port become those associated with vessel's starboard and vice versa, in terms of how the vessel thrust is applied and how the vessel is steered and manoeuvred. Should the device 1 be mounted on the arm of a chair, die control system may include a switch input that when the chair is rotated to face from fonvard to aft, the switch is activated and the system then switched from fonvard to aft facing mode.

The device may be arranged to wirelessly communicate with the vessel's control system, for example via a radio communication link, to provide the operator of the device with the freedom to move around the vessel bridge (without being restricted by cables attached to the device).

Element 7 of device 1 may include a switch that when the element 7 is pressed vertically downward with some force by the users fingers or thumb, would produce an input into the control system to reduce the thrust vectors to zero while the system was in docking mode or reduce the engine throtde demand to idle die engine while in cruise mode.

• The device may include and wrist strap to tedier the device to a user to provide improved steering control when die vessel is traveling at speed in high sea state conditions.

Example 1 -

Control Device for a Vessel with Multiple Waterjet Units

(Differential Thrust Capable) Referring to Figure 7, a schematic arrangement of the control device 1 described above installed in a vessel propelled by twin waterjet units 1 1 1 is shown. The waterjet units 1 1 1 are typically placed port and starboard at the stern of the vessel. Two, three, four or possibly more units may be controlled together. Each unit is driven by an engine 113 through a driveshaft 1 14 and has a housing containing a pumping unit 1 12, steering deflector 1 15 and reverse duct 1 16. In d is case the reverse ducts are each of a type that feature split passages to improve reverse tiirust and affect the steering thrust to port and starboard when die duct is lowered into d e jet stream. The steering deflectors pivot about generally vertical axes 1 17 while the reverse ducts pivot about generally horizontal axes 1 18 independendy of the deflectors. Actuation of the engine throtde, and of the steering deflector and reverse duct of each unit is caused by actuation signals received through control input ports 1 19, 120, 121 respectively.

For clarity, the control device 1 is shown as die only manual control device for the vessel, although it will be appreciated that in practice it may supplement other steering and tiirust control system arrangements which utilise a joystick, a helm control, and throtde lever(s) for higher speed or all speed control.

As mentioned, command signals 122 are generated in response to the rotational angle from neutral applied to the control element 3 and/or in response to pressure being applied to the pressure sensing mechanism (or switch activation) by an operator and the rotated position of element 7 (if included). The signals 122 are received by a control system 123, and are processed and sent 124 to actuator modules 125 to operate the waterjet units and engine throtdes to manoeuvre the vessel. In particular, the actuator modules 125 generate actuation signals 126 which are input through ports 1 19, 120, 121 to control the engine throtde, and steering deflector and reverse duct of each waterjet unit. While the control device 1 is shown as hardwired to the actuator modules 125, alternatively the control device 1 may, for example, be a remote unit which communicates with the vessel's control system and/ or actuator modules via a wireless link.

Figure 8 shows six basic low speed manoeuvres of a vessel which may be enabled by the control device 1. These include four translations a, b, e and f in which the vessel moves ahead, astern, to port or to starboard respectively, while maintaining a constant compass heading. Figure 8 also shows two rotations c and d in which the vessel turns to port or starboard about a centre point in the vessel respectively. Manoeuvres resulting from the operation of the device 1 in each case are shown. The steering deflectors are operated in synchronism while the reverse ducts are operated in synchronism or differentially as summarised in Table 1 below. Virtually any movement of the vessel may be achieved by a combination of these basic manoeuvres. The control device is intended to allow an operator to use the control element 3 and the pressure sensitive mechanism in a simple intuitive fashion to cause movement of the vessel i.e. the vessel's movement mimics manipulation of the device inputs.

Applying pressure to the pressure sensitive elements associated with ahead or astern synchronises the reverse ducts and throttle demands and the effect is the same as operating a vessel with a single waterjet in manoeuvres a and b. While located at its neutral position, applying clockwise or anticlockwise angular rotation to the control element 3 in manoeuvres c and d causes a partial lowering of die reverse ducts to the zero speed position and movement of the steering deflectors to rotate the vessel about its centre in a corresponding direction to the degree as a function of the device's steering angle from neutral. Applying pressure to the pressure sensitive elements associated with port and starboard causes the vessel to translate sideways in manoeuvres e and f via a combination of differential thrust of each waterjet and a steering offset to counter die rotation. In particular, the port and starboard waterjets produce differential thrust (i.e. one waterjet unit produces ahead thrust with the reverse duct raised while the other produces astern dirust with the reverse duct lowered) which causes die vessel to rotate about the stern. However, die steering ^' deflectors of the waterjet units are also positioned to counteract this rotation, resulting in a sideways translation of die vessel. It is known diat when die reverse duct is fully lowered, the reveres dirust vector imposed onto the vessel is not as efficient (or as strong) as that of the jets providing forward thrust vectors (bucket not lowered). This causes the forward and the reverse thrust vectors (differential thrust) to not be exacdy equal and to compensate, diose skilled in die art know diat adjustments to this dirust imbalance can be achieved by increasing the engine RPM associated with the reversing waterjet or slight lowering die waterjet bucket on the waterjet diat is providing die ahead thrust vector. The control system may automatically apply a preset movement of die steering nozzles ("steering offset") upon sensing pressure on the left/right hand sides of surface 6. Alternatively die degree of steering offset applied may be varied by die control system to be proportional to the thrust level simultaneously commanded by the operator. Alternatively again an autopilot system associated with the control system may operate in conjunction with the control system to maintain a constant commanded heading (direction of the bow of the vessel) during the sideways translation - that is, when the operator applies pressure on surface 6 to command a port or starboard sideways translation of the vessel, the position of the steering nozzles may be controlled by the control system but based on heading information provided by an autopilot system, so that the steering nozzles are initially positioned and adjusted as necessary by the control system dunng the translation movement, to maintain a constant heading, or a commanded heading, for the vessel from the autopilot. Alternatively again a rate sensor arranged to generate a turn rate signal indicative of vessel turn rate mav be provided and the control system may be configured to monitor for any turn via the turn rate sensor at the bow of the vessel, and to adjust the position or angle of the steering nozzles to compensate so as to maintain a constant heading during a sideways translation; the control system may be configured to receive a vessel actual turn rate signal from the turn rate sensor and a desired turn rate signal and to compare the two and to control the steering nozzles to minimise a difference between the signals, and maintain or initiate a desired turn rate where the control device is manipulated by the operator to cause the vessel to also turn during a sideways translation of the vessel; the turn rate sensor may be a yaw rate sensor for example a rate gyro fixed to the vessel to sense yaw motions of die vessel. Any of these functionalities for providing steering offset via the control system during a sideways translation may be provided to the system described in subsequent example 2.

Figure 9 schematically shows a vessel 127 with a twin waterjet arrangement and control device 1 according to the invention. A sideways manoeuvre to port is in progress, such as manoeuvre e indicated in Figure 8. Nozzles 128, steering deflectors 129 and one of the reverse ducts 130 are shown at the stern of die vessel to indicate the port and starboard waterjets. The reverse duct on the starboard waterjet is not positioned to deflect the water flow from that jet and has been omitted from view. Pressure 10 has been applied at port side of surface 6 of element 3 by the operator. This produces jet streams 131 from the waterjets and consequendy thrust vectors 132. The net sideways force acts at a point 133 towards the centre of the vessel represented by thrust vector 134.

It will be appreciated that die control device may be provided with one or more additional manually operable control inputs in die form of a thumbwheel 7 or other input device as discussed above to control thrust gain and that the control system may be arranged to operate the waterjet units 1 1 1 and/ or engines 113 in accordance widi the operation of the additional control input(s).

The control device may also be operated to manoeuvre the twin waterjet vessel at higher speeds when cruising. As mentioned above, the control device may have a mode change button 5 or the like for switching between a low speed mode and a cruise mode. Operation of the control device in the low speed mode has been described above widi reference to Figure 8 and Table 1. When in cruise mode, the control system 123 (Figure 7) disregards port and starboard pressure signals which represent sway demands (transverse translational movements) and therefore does not operate the waterjet units 1 1 1 to produce differential thrust. The control device 1 only controls the surge of the vessel and the yaw or steering of the vessel. In particular, the control system 123 operates the engine throtdes 1 13 and reverse ducts 1 16 of the waterjet units 1 1 1 in a synchronised manner in accordance widi force on the surface 6 at the top and bottom regions to surge the vessel fore and aft as desired, and operates the steering deflectors 1 15 in accordance with rotational angle applied to the control element 3 to yaw or steer the vessel to port or starboard as desired. Example 2 -

Control Device for a Vessel with Single Waterjet Unit and Lateral Thruster(s)

Referring to Figure 10, a schematic arrangement of the control device 1 described above installed in a vessel propelled by a single waterjet unit 1 1 1 is shown. The waterjet unit 1 1 1 is typically placed in the centre at the stern of die vessel and has die same assembly and componentry as was described in respect of die waterjet units in Figure 7. In die bow 135 of the vessel is a bow thruster 136 which is operable to produce lateral thrust forces to either port or starboard as indicated by thrust vectors 137,138 respectively.

The bow thruster 136 has, for example, an impeller driven by a reversible motor. The reversible motor is operated by an actuator module 139 which sends actuation signals 140 to control die speed and direction of the reversible motor and thereby die direction and magnitude of the lateral thrust produced by the bow diruster 136.

In operation, the control device 1 controls the waterjet unit 11 1 , engine 113, and bow diruster 136 via their respective actuation modules 125,139 to manoeuvre the vessel during, for example, low speed operations such as docking and setting off in a marina or the like. In particular, thrust and steering command signals 122 are generated in response to the fore-aft, port-starboard, pressure inputs and the rotational inputs applied to the control device 1 by an operator respectively. The signals 122 are received by a control system 123, and are processed and sent 124,141 to actuator modules 125, 139 to operate the waterjet unit 1 11 , engine 1 13, and bow thruster 136 to manoeuvre the vessel. As mentioned, the actuator module 125 generates actuation signals 126 which are input through ports 1 19, 120, 121 to control die engine dirotde, and steering deflector and reverse duct of the waterjet unit 1 1 1 , while actuator module 139 generates actuation signals 140 to control the speed and dnection of the reversible motor of the bow thruster 136.

Figure 1 1 shows the same six basic low speed manoeuvres shown previously, except for a single waterjet vessel with a bow thruster as illustrated in Figure 10. As with the twin waterjet vessel embodiments of example 1 , the basic manoeuvres are enabled by the control device 1 and include four translations a, b, e and f in which the vessel moves ahead, astern, to port or to starboard respectively, while maintaining a constant compass heading. Figure 1 1 also shows two rotations c and d in which the vessel turns to port or starboard about a centre point in the vessel respectively. The waterjet unit 1 1 1 and bow thruster 136 are operated as summarised in Table 2 below for the six basic manoeuvres. Virtually any movement of the vessel may be achieved by a combination of these basic manoeuvres. As shown in Figure 12, the control system operates the waterjet unit 11 1 and bow thruster 136 to cause the vessel to move in such a way that mimics the manipulation of the device 1 inputs.

TABLE 2: SUMMARY OF 6 BASIC VESSEL MANOEUVRES

In a vessel with a single waterjet unit and without lateral thruster(s) the control system may be arranged to cause the vessel to achieve a translation to port or starboard by manoeuvring the vessel forward and turning to the required direction and dien moving the vessel astern and turning to die desired direction in a small zig-zag path, with the final results being as if the vessel had translated direcdy sideways.

Like the twin waterjet vessel embodiment described above, the control device may be equipped with one or more additional manually operable control inputs in the form of a thumbwheel 7 or similar for controlling thrust gain for example. The control device may also be operated to manoeuvre the single waterjet vessel with bow thruster at higher speeds when cruising by changing the control device from a low speed mode to cruise mode via operation of a button, switch or the like. Operation of die control device in die low speed mode has been described above with reference to Figure 1 1 and Table 2. When in cruise mode, the control system 123 (Figure 10) disregards the port and starboard pressure signals which represents sway demand (transverse translational movements) and therefore completely disables the bow diruster to prevent lateral dirust being produced at higher speeds. The control device 1 only controls die surge of the vessel and the yaw or steering of the vessel. In particular, die control system 123 operates the engine dirotde 1 13 and reverse duct 1 16 of the waterjet unit 1 1 1 in accordance with force applied to the surface 6 at die top or bottom regions (12 o'clock and 6 o'clock position) to surge the vessel forward or aft as desired, and operates the steering deflector 1 15 in accordance with rotational angle applied to the control element 3 to yaw or steer die vessel to port or starboard as desired. Alternatively or additionally element 7 of device 1 may control the engine dirotde demand and/ or the bucket demand.

It will be appreciated that the vessels described in examples 1 and 2 could additionally utilise one or more other lateral thrusters to assist the bow thruster and diat all the lateral thrusters may be controlled by die control device according to the particular manoeuvre desired. For example, the vessels may have one or more bow thrusters and one or more stern thrusters that assist die waterjet unit(s) to manoeuvre die vessel as desired by the operator as they apply pressure to die surface 6 of control element 3 of die control device 1.

The foregoing describes the invention including a preferred form thereof. Alterations and modifications as would be obvious to those skilled in the art are intended to be incorporated within the scope hereof as defined in the accompanying claims.