Ship propulsion system and control method of the same and ship

Abstract

To improve a function for translation.SOLUTION: A controller 70 controls outboard engines 4L, 4R so as to cause resultant force FS to act on a point of application F0 determined on the basis of a targe direction and required propulsion power during translation and controls a trolling motor 5 so as to exert motor propulsion power TF for cancelling a turning component by the resultant force FS and a component in a direction perpendicular to the target direction. The controller 70 moves a position of the point of application F0 rearward or increases the resultant force FS in response to increase of the required propulsion power during the translation. The controller 70 increases propulsion power of a forward movement propeller when the point of application F0 reaches a rear limit position and propulsion power of a rearward movement propeller reaches upper limit propulsion power.SELECTED DRAWING: Figure 8

Description

[Technical field]

[0001] The present invention relates to a ship propulsion system, a control method thereof, and a ship. [Background technology]

[0002] 2. Description of the Related Art Conventionally, a boat propulsion system is known that includes a propulsion unit arranged forward of the stern, in addition to a propulsion unit such as an outboard motor arranged at the stern.

[0003] For example, the vessel in Patent Document 1 is equipped with two propulsion units (outboard motors) at the stern and a bow thruster at the bow, enabling parallel movement such as lateral movement. For example, during lateral movement, one of the two outboard motors applies a propulsive force including a reverse component to the hull, and the other applies a propulsive force including a forward component to the hull, and the resultant force acts on a point of application behind the center of gravity. The bow thruster then suppresses or promotes turning. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] JP 2020-168921 A Summary of the Invention [Problem to be solved by the invention]

[0005] However, there is a practical upper limit to the propulsive force that a stern thruster can generate. For example, in the case of a thruster that generates a propulsive force that includes a reverse component, the rotation speed must be controlled to a range in which cavitation does not occur. On the other hand, a bow thruster does not have a steering function and cannot generate a forward / rearward component.

[0006] For this reason, during lateral movement, it is necessary to control the resultant force of the two propulsors so that it does not include a forward or backward component. As a result, the maximum output of the propulsion unit that generates a propulsive force including a forward component is restricted by the maximum output of the propulsion unit that generates a propulsive force including a backward component.

[0007] In this way, the thrust in the lateral direction is limited to a certain level, which restricts the lateral movement performance. This is not limited to the case of moving directly to the side, but also applies to the case of moving diagonally in parallel without turning.

[0008] An object of the present invention is to provide a vessel propulsion system capable of improving the performance of parallel movement. [Means for solving the problem]

[0009] A vessel propulsion system according to one aspect of the present invention includes a plurality of steerable first propulsion units disposed at the stern of a hull, a steerable second propulsion unit disposed at a predetermined position forward of the stern of the hull, an acquisition unit that acquires a target direction and a required propulsive force when a command for parallel movement is obtained or when it is determined that a parallel movement is to be performed, and a unit that, during the parallel movement, determines a point of application of a resultant force of propulsive forces that each of the plurality of first propulsion units applies to the hull based on the acquired target direction and required propulsive force, controls the plurality of first propulsion units so that a resultant force in the target direction corresponding to the required propulsive force applies to the determined point of application, and controls the vessel to turn relative to the hull using the resultant force. and a control unit that controls the second propulsion unit to apply a thrust force to the specified position to offset a thrust component in a direction perpendicular to the target direction and a thrust component in a direction perpendicular to the target direction, wherein the control unit moves the position of the point of application rearward or increases the thrust of each of the multiple first propulsion units in response to an increase in the required thrust during translation, and when the position of the point of application reaches a determinable rearward limit position during translation and the thrust of a propulsion unit among the multiple first propulsion units that is applying a thrust component in a backward direction reaches an upper limit thrust that can be generated, the control unit increases the thrust of a propulsion unit among the multiple first propulsion units that is applying a thrust component in a forward direction.

[0010] With this configuration, when a command for parallel movement is obtained or when it is determined that parallel movement will be performed, a target direction and a required propulsive force are obtained, and during the parallel movement, a point of application of a resultant force of propulsive forces to be applied to the hull by each of the multiple first propulsors is determined based on the obtained target direction and required propulsive force, and the multiple first propulsors are controlled to apply a resultant force in the target direction corresponding to the required propulsive force to the determined point of application, and the second propulsor is controlled to apply a propulsive force to a predetermined position to offset a turning component of the resultant force with respect to the hull and a component in a direction perpendicular to the target direction. As the required propulsive force increases during the parallel movement, the position of the point of application is moved rearward or the propulsive force of each of the multiple first propulsors is increased, and when, during the parallel movement, the position of the point of application reaches a determinable rearward limit position and the propulsive force of a propulsion unit among the multiple first propulsors that is applying a propulsive force in the reverse direction reaches an upper limit propulsive force that can be generated, the propulsive force of the propulsion unit among the multiple first propulsors that is applying a propulsive force in the forward direction is increased. Effect of the Invention

[0011] According to the present invention, the performance of translation can be improved. [Brief description of the drawings]

[0012] [Figure 1] 1 is a schematic top view of a vessel to which a vessel propulsion system is applied; [Diagram 2] FIG. 1 is a schematic side view of bow and stern portions of a ship. [Diagram 3] FIG. [Figure 4] FIG. 2 is a view of the steering wheel seen from approximately the front. [Diagram 5] FIG. 1 is a block diagram of a marine vessel propulsion system. [Figure 6] FIG. 4 is a schematic diagram showing a propulsive force acting on a hull in a translation mode. [Figure 7] 11A and 11B are schematic diagrams showing the transition of the action of a propulsive force in a translation mode. [Figure 8]13 is a flowchart of a parallel movement mode process. [Figure 9] FIG. 13 is a transition diagram when the stick portion is twisted in the parallel movement mode. [Figure 10] FIG. 13 is a transition diagram when the stick portion is twisted in the parallel movement mode. [Figure 11] FIG. 13 is a transition diagram when the stick portion is twisted in the parallel movement mode. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0013] Hereinafter, an embodiment of the present invention will be described with reference to the drawings.

[0014] 1 is a schematic top view of a boat 1 to which a boat propulsion system according to an embodiment of the present invention is applied.

[0015] In the figure, the forward direction (bow direction) of the ship 1 is indicated by an arrow FWD, and the astern direction (stern direction) is indicated by an arrow BWD. Furthermore, the starboard side direction of the ship 1 is indicated by an arrow R, and the port side direction is indicated by an arrow L.

[0016] The centerline C of the hull 2 ​​passes through the center of the stern 2A and the tip of the bow 2B. The centerline C passes through the center of gravity G (center of turning) of the ship 1. The fore-aft direction is a direction parallel to the centerline C. The forward direction is the direction upward along the centerline C in Figure 1 (the direction of the bow 2B when viewed from the stern 2A). The rearward direction is the direction downward along the centerline C in Figure 1. The left-right direction is based on the view of the hull 2 ​​from the rear. The up-down direction is a direction perpendicular to the fore-aft direction and the left-right direction.

[0017] The boat 1 is equipped with steerable outboard motors 4L, 4R (first propulsion units) and a steerable trolling motor 5 (second propulsion unit) as propulsion units for propelling the hull 2. The outboard motors 4L, 4R are disposed at the stern 2A, and the trolling motor 5 is disposed at the bow 2B. The trolling motor 5 only needs to be disposed at a predetermined position in front of the stern 2A of the hull 2, and its position is not limited to the bow 2B. The outboard motors 4L, 4R and the trolling motor 5 may be the main propulsion units and the auxiliary propulsion unit of the boat 1, respectively.

[0018] The outboard motors 4L, 4R are mounted at the stern 2A at positions symmetrical on the left and right sides with respect to the center line C. The outboard motor 4L is mounted at the port rear, and the outboard motor 4R is mounted at the starboard rear.

[0019] The boat 1 is equipped with a steering wheel 11 that is operated mainly for steering, a remote control unit 12 that is operated mainly for adjusting the output of the outboard motors 4L, 4R, and a joystick 13 that is operated mainly for steering and adjusting the output of the outboard motors 4L, 4R. The remote control unit 12 includes two throttle levers 12L, 12R, and is operated to adjust the output of the engines of the outboard motors 4L, 4R and to switch between forward and reverse travel. Each throttle lever can be operated in the forward and reverse directions from a zero operating position. Note that the layout of these is not limited to that shown in the figure.

[0020] FIG. 2 is a schematic side view of the bow and stern portions of the vessel 1. As shown in FIG.

[0021] Each of the outboard motors 4L, 4R has an outboard motor body 20 and a propeller 21 (Fig. 1). Since the outboard motors 4L, 4R have the same configuration, the detailed configuration of the outboard motor 4L will be described as a representative. The propeller 21 and a skeg 23 (rudder) are disposed at the bottom of the outboard motor body 20. The outboard motor body 20 is attached to the stern 2A by an attachment mechanism 22. The attachment mechanism 22 includes a clamp bracket that is detachably fixed to the stern 2A, and a swivel bracket that is connected to the clamp bracket so as to be rotatable about a tilt axis. The outboard motor body 20 is attached to the swivel bracket so as to be rotatable about a steering axis center K (Fig. 1). The steering angle of the outboard motor 4L changes as the outboard motor body 20 rotates about the steering axis center K.

[0022] Unlike a bow thruster (not shown), the trolling motor 5 is an aftermarket part that can be attached later to the completed boat 1. The trolling motor 5 is designed to provide the hull 2 ​​with a propulsive force in any direction about a rotation axis J (FIG. 1), which is the center line of the rotation shaft 52.

[0023] The trolling motor 5 is electrically powered. The trolling motor 5 includes an electric motor 50 and a propeller 51 that generates propulsive force by being rotationally driven by the electric motor 50. The trolling motor 5 further includes a rotating shaft 52 that extends upward from the electric motor 50 through the rotation axis J, and a bracket 53 that is fixed to the bow 2B and supports the rotating shaft 52 rotatably around the rotation axis J. The electric motor 50 rotates around the rotation axis J together with the rotating shaft 52.

[0024] The upper part of the rotating shaft 52 protrudes upward beyond the bracket 53. A control panel 54 having an indicator (not shown) that indicates the direction of the propeller 51 in water and the like is provided at the upper end of the rotating shaft 52. An operation unit (not shown) such as a foot pedal that allows the operator to directly operate the trolling motor 5 is provided on the bracket 53. In addition, a wireless remote control (not shown) that allows the operator to operate the trolling motor 5 may be provided. Note that the control panel 54 is not shown in FIG. 1.

[0025] The trolling motor 5 includes, for example, an electric steering unit 56 built into the bracket 53 and rotating the rotating shaft 52 and the electric motor 50 around the rotation axis J, and an ECU (not shown) built into the operation panel 54 and controlling the electric motor 50 and the steering unit 56.

[0026] The steering unit 56 is composed of, for example, a servo motor. The orientation of the trolling motor 5 can be changed by a steering operation by the steering unit 56. First, the steering unit 56 changes the direction of the propulsive force generated by the rotating propeller 51 by rotating the electric motor 50 around the rotation axis J to change the orientation of the electric motor 50 within a range of 360 degrees or more. This changes the steering angle of the trolling motor 5, and changes the direction of the propulsive force that the trolling motor 5 applies to the hull 2.

[0027] The bracket 53 is capable of rotating up and down relative to the hull 2 ​​by a rotating shaft 59. The bracket 53 rotates about the rotating shaft 59, thereby allowing the trolling motor 5 to move between a use position and a stored position. Figures 1 and 2 show the trolling motor 5 in the use position. When the trolling motor 5 is in the use position, the electric motor 50 and the propeller 51 are positioned below the waterline (not shown).

[0028] In this embodiment, the multiple maneuvering modes are roughly divided into an outboard motor mode in which the trolling motor 5 is not used, and a linked mode in which the trolling motor 5 is used in combination with the outboard motors 4L, 4R. The outboard motor mode is a maneuvering mode in which the outboard motors 4L, 4R are controlled mainly based on the rotational operation of the steering wheel 11 and the operation of the remote control unit 12.

[0029] The linked modes include an automatic ship-steering mode, a joystick mode, and a drive mode. The joystick mode is a ship-steering mode in which the outboard motors 4L, 4R and the trolling motor 5 are controlled based on the operation of the joystick 13. The drive mode is a ship-steering mode in which the outboard motors 4L, 4R and the trolling motor 5 are controlled based on the operation of various switches and paddles on the steering wheel 11 (described later) and the rotation of the steering wheel 11.

[0030] The automatic ship-steering mode is a mode in which, when a target position or a target heading of the hull 2 ​​is specified, the outboard motors 4L, 4R and the trolling motor 5 are controlled to automatically maintain the trajectory, heading or position of the hull 2. Typical examples of the automatic ship-steering mode include a stay point, a fish point, and a drift point.

[0031] 3 is a perspective view of the joystick 13. The joystick 13 includes a main body portion 13a and a columnar stick portion 13b extending upward from the main body portion 13a.

[0032] The main body 13a is provided with a stay point button 13c, a fish point button 13d, a drift button 13e, and a joystick button 13f. The stay point button 13c accepts an operation to switch the stay point on and off. The fish point button 13d accepts an operation to switch the fish point on and off. The drift button 13e accepts an operation to switch the drift point on and off. The joystick button 13f accepts an operation to switch the joystick mode on and off.

[0033] The stay point is an automatic ship steering mode in which the heading of the bow 2B of the hull 2 ​​is maintained at a set target heading, and the position of the hull 2 ​​is maintained at a set target point. The fish point is an automatic ship steering mode in which the hull 2 ​​is turned to face a set target point, and the moving direction of the hull 2 ​​is maintained at the target point. The drift point is an automatic ship steering mode in which the hull 2 ​​is moved by receiving external forces including wind and water flow, while the heading of the bow 2B of the hull 2 ​​is maintained at the target heading by turning the hull 2. It is not essential that the main body 13a has all of the above-mentioned buttons.

[0034] 4 is a view of the steering wheel 11 seen substantially from the front. The steering wheel 11 has a central portion 44, an annular wheel portion 43, and three spoke portions (a first spoke portion 45, a second spoke portion 46, and a third spoke portion 47). The steering wheel 11 is supported by the hull 2 ​​so as to be rotatable about a rotation fulcrum C0.

[0035] The steering wheel 11 includes a plurality of switches. For example, a changeover switch 69, a left switch 63, and a right switch 64 are arranged on the surface of the steering wheel 11. The steering wheel 11 also includes a left paddle section 67 and a right paddle section 68. The left paddle section 67 and the right paddle section 68 are rotatable in the front-rear direction. The left paddle section 67 and the right paddle section 68 are operation sections for instructing the hull 2 ​​to apply rearward and forward propulsive forces, respectively.

[0036] When the left paddle unit 67 is operated, the controller 70 changes the magnitude of the rearward propulsive force in accordance with the amount of operation of the left paddle unit 67, and when the right paddle unit 68 is operated, the controller 70 changes the magnitude of the forward propulsive force in accordance with the amount of operation of the right paddle unit 68. Mainly in the drive mode, the controller 70 controls the trolling motor 5 and the outboard motors 4L, 4R based on operation signals from the switches 63, 64 and the paddle units 67, 68.

[0037] In joystick mode and drive mode, parallel movement including lateral movement as well as turning on the spot are possible.

[0038] Here, translation means that the hull 2 ​​moves horizontally around the center of gravity G (Figure 1) without rotating in the yaw direction. For example, in lateral movement, the hull 2 ​​moves left or right without turning. It is also possible to translate the hull 2 ​​diagonally (diagonally left / right and front / rear) by applying a propulsive force in the fore / aft direction during lateral movement. In on-the-spot turning, the hull 2 ​​rotates in the yaw direction around the center of gravity G. There are also cases where a combination of translation and turning is applied.

[0039] Regarding operation, for example, when parallel movement is performed in joystick mode, the hull 2 ​​moves parallel in the direction in which the stick unit 13b is tilted. When parallel movement is performed in drive mode, the hull 2 ​​moves laterally to the left and right when the left switch 63 and right switch 64 are operated, respectively. When the paddle units 67 and 68 are operated, the hull 2 ​​moves backward and forward, respectively. Note that when either the paddle units 67 and 68 are operated in parallel with the operation of the left switch 63 or the right switch 64, forward and backward movement is added to the lateral movement, and the hull 2 ​​moves parallel in an oblique direction.

[0040] The stick portion 13b can be twisted (or rotated) around the axis of the stick portion 13b, and in the joystick mode, a turning (or pivoting) command can be issued by twisting the stick portion 13b. In the drive mode, a turning (or pivoting) command can be issued by rotating the wheel portion 43.

[0041] A biasing portion (not shown) is provided in the tilting and twisting directions of the stick portion 13b of the joystick 13, and the joystick 13 is always biased toward the neutral position. Therefore, when the operator releases the joystick 13, the joystick 13 automatically returns to the neutral position.

[0042] 5 is a block diagram of the boat propulsion system. The boat propulsion system includes a controller 70, outboard motors 4L and 4R, a trolling motor 5, a steering wheel 11, a remote control unit 12, a joystick 13, a display unit 14, various sensors 15, various controls 16, and a memory 17.

[0043] The controller 70 includes a CPU 71, a ROM 72, a RAM 73, and a timer (not shown). The ROM 72 stores a control program. The CPU 71 realizes various control processes by expanding the control program stored in the ROM 72 into the RAM 73 and executing it. The RAM 73 provides a work area when the CPU 71 executes the control program.

[0044] The various sensors 15 include a hull speed sensor, a hull acceleration sensor, a direction sensor, a distance sensor, an attitude sensor, a position sensor, and a GNSS (Global Navigation Satellite System) sensor. The various sensors 15 also include a sensor that detects the operation of the remote control unit 12, a sensor that detects the rotation angle position of the steering wheel 11, a sensor that detects the operation of each switch and paddle part of the steering wheel 11, and a sensor that detects the operation of the joystick 13. The hull speed sensor detects the sailing speed (ship speed) of the ship 1 (hull 2). The ship speed may be obtained from a GNSS signal received by a GNSS sensor. Detection signals from the various sensors 15 are supplied to the controller 70.

[0045] The various operators 16 include operators for performing operations related to maneuvering the vessel, setting operators for making various settings, and input operators for inputting various instructions. Some of the various operators 16 may be disposed on the steering wheel 11. The various operators 16 are operated by the vessel operator, and the operation signals thereof are supplied to the controller 70. The memory 17 is a readable and writable non-volatile storage medium.

[0046] The controller 70 may establish predetermined communications with the various sensors 15 and the various operators 16 to exchange information with them. The display unit 14 displays various types of information.

[0047] The outboard motors 4L, 4R each have an ECU (engine control unit) 81, an SCU (steering control unit) 82, a rotation speed sensor 83, an engine 84, a steering mechanism 85, various sensors 86, a steering angle sensor 87, and various actuators 88. The ECU 81 and the SCU 82 each include a CPU (not shown). The ECU 81 controls the operation of the engine 84 based on commands from the controller 70. The SCU 82 controls the operation of the steering mechanism 85 based on commands from the controller 70.

[0048] The steering mechanism 85 changes the left and right direction of the outboard motor body 20 by rotating the outboard motor body 20 about the steering axis center K (FIG. 1). This changes the direction of the propulsive force acting on the stern 2A, where the outboard motor body 20 is attached. The steering mechanism 85 may be either electric or hydraulic. The various actuators 88 may include a power trim and tilt mechanism (PTT mechanism) that rotates the outboard motors 4L, 4R about a tilt axis.

[0049] The rotation speed sensor 83 detects the rotation speed per unit time of the engine 84. The various sensors 86 include a throttle opening sensor and the like. The steering angle sensor 87 detects the actual steering angles of the outboard motors 4L, 4R. The controller 70 may obtain the actual steering angle from a steering command value output to the steering mechanism 85.

[0050] The trolling motor 5 includes, in addition to the electric motor 50 and the steering unit 56, an MCU (motor control unit) 57, an SCU (steering control unit) 58, a steering angle sensor 55, various sensors 60, and an actuator 61.

[0051] Each of the MCU 57 and SCU 58 includes a CPU (not shown). The MCU 57 controls the driving of the electric motor 50 based on commands from the controller 70. The maximum output of the electric motor 50 may be smaller than the maximum output of the engines 84 of the outboard motors 4L, 4R. The SCU 58 controls the driving of the steering unit 56 based on commands from the controller 70, thereby changing the direction of the propulsive force acting on the bow 2B, which is the mounting position of the trolling motor 5.

[0052] The actuator 61 moves the trolling motor 5 between a use position and a storage position. However, it is not essential to provide a function for transitioning the trolling motor 5 between the use position and the storage position by power.

[0053] The steering angle sensor 55 detects the steering angle of the trolling motor 5 by the steering unit 56. Detection signals by the steering angle sensor 55 and the various sensors 60 are supplied to the controller 70. It is not essential that the outboard motors 4L, 4R and the trolling motor 5 are provided with all of the above-mentioned sensors and actuators.

[0054] Strictly speaking, the points at which the propulsion force of each propulsion unit acts are the points at which each propulsion unit is attached to the hull 2. However, for ease of explanation, it is considered that the propulsion force of the trolling motor 5 acts on the bow 2B, and the propulsion forces of the outboard motors 4L, 4R act on the positions of the respective mounting mechanisms 22 at the stern 2A.

[0055] Fig. 6 is a schematic diagram showing the propulsive force acting on the hull 2 ​​in the parallel translation mode. For convenience, it is assumed that the position of the center of rotation when the hull 2 ​​turns coincides with the center of gravity G. Fig. 6 shows an example in which the hull 2 ​​translates in a particularly lateral direction when the trolling motor 5 is not used. The parallel translation mode is implemented, for example, when a command to implement parallel translation is received.

[0056] As shown in FIG. 6, in the parallel movement mode in which the hull 2 ​​moves laterally to the right, the line of action 4L-P of the first propulsive force of the outboard motor 4L and the line of action 4R-P of the second propulsive force of the outboard motor 4R intersect at the center of gravity G. In this case, the first propulsive force FL of the outboard motor 4L is a vector pointing to the right front, and the second propulsive force FR of the outboard motor 4R is a vector pointing to the right rear. The resultant force of the first propulsive force FL and the second propulsive force FR becomes the resultant force FS. The resultant force FS is a vector pointing to the right. Therefore, with the center of gravity G as the point of action F0, the resultant force FS in the right direction acts as a propulsive force on the hull 2. Therefore, since no rotational moment acts on the hull 2, the hull 2 ​​moves laterally to the right without turning.

[0057] In addition, in the parallel translation mode in which the boat moves laterally to the left, the left-right direction can be understood as being reversed with respect to the example shown in Fig. 6. In this way, when the propulsive force of the trolling motor 5 is not used, the hull 2 ​​does not turn if the resultant force FS of the propulsive forces of the outboard motors 4L, 4R is applied to the center of gravity G. However, in this embodiment, the propulsive force of the trolling motor 5 is also used, and further the turning of the hull 2 ​​and unnecessary directional components are compensated for by the trolling motor 5, thereby realizing parallel translation more efficiently.

[0058] Figures 7(a)-(h) are schematic diagrams showing the transition of propulsive force action in the translation mode. Figures 7(a)-(d) show the transition during lateral movement to the right, and Figures 7(e)-(h) show the transition during translation diagonally forward to the right. The propulsive force of the trolling motor 5 is shown as motor propulsive force TF. The direction and length of the arrows for the resultant propulsive forces FS of the outboard motors 4L and 4R and the motor propulsive force TF respectively indicate the direction and magnitude of the propulsive force.

[0059] First, the transition during lateral movement to the right (FIGS. 7(a) to (d)) will be described.

[0060] When the parallel movement mode is set, the steering angles of the outboard motors 4L, 4R are controlled so that the action point F0 of the resultant force FS is at the standby position. The standby position is, for example, the same as the center of gravity G, but may be in front of or behind the center of gravity G.

[0061] When an instruction for parallel movement is acquired or when it is determined that parallel movement is to be performed, the controller 70 as an acquisition unit acquires, from the steering instruction content, the direction of parallel movement (target direction) and the required propulsive force, which is the propulsive force required to translate the hull 2 ​​in the target direction. Here, the steering instruction is input by operating the joystick 13 in the joystick mode, and is input by operating at least one of the switches 63, 64 and the paddle sections 67, 68 of the steering 11 in the drive mode.

[0062] For example, in the joystick mode, the target direction is input by the tilt direction of the stick portion 13b, and the required thrust is input by the tilt angle, which is the amount of operation. For example, when the stick portion 13b is tilted to the right, a right lateral movement is instructed, and the required thrust is input by the tilt angle.

[0063] In the drive mode, the target direction is input by a combination of the operations of the switches 63, 64 and the paddles 67, 68, and the required thrust is input by a combination of the amounts of operation of each. For example, when only the right switch 64 is operated, a right lateral movement is instructed, and the required thrust is input according to the amount of depression.

[0064] In addition, in the automatic ship maneuvering mode, a parallel movement instruction may be generated at the discretion of the controller 70, in which case the generated target direction and required propulsive force are treated in the same way as the input values.

[0065] The controller 70 as a control unit determines the point of application F0 based on the acquired target direction and required propulsive force during the parallel movement, and controls the outboard motors 4L, 4R to apply a resultant force FS in the target direction corresponding to the required propulsive force to the determined point of application F0. Furthermore, in parallel with moving the point of application F0 rearward, the controller 70 executes "compensation control" (described later) by applying a motor propulsive force TF by the trolling motor 5. The compensation control is applied as needed during the parallel movement.

[0066] In compensation control, the controller 70 controls the trolling motor 5 to apply a propulsive force to the bow 2B (the mounting position of the trolling motor 5) to offset the turning component of the resultant force FS relative to the hull 2 ​​and the component perpendicular to the target direction (the fore-aft component in the case of lateral movement).

[0067] Immediately after a steering command for lateral movement is input, a resultant force FS in the right direction acts on the point of action F0 (FIG. 7(a)). After this, the controller 70 moves the point of action F0 rearward as the required thrust increases (FIG. 7(b)). In other words, the acute angle formed rearward between the first thrust line of action 4L-P and the second thrust line of action 4R-P (FIG. 6) is controlled to gradually increase.

[0068] As shown in FIG. 7(b), when the point of application F0 moves rearward from the center of gravity G, a counterclockwise moment (turning component) is applied by the resultant force FS. To counter this, the controller 70 controls the trolling motor 5 to apply a motor propulsive force TF including a turning component to the right. The magnitude of the motor propulsive force TF is set to a value that cancels out the turning component of the resultant force FS on the hull 2. As a result, the hull 2 ​​does not turn. In the example shown in FIG. 7(b), since the hull 2 ​​is moving directly alongside, the direction of the motor propulsive force TF may remain to the right as long as the resultant force FS is directed to the right.

[0069] The controller 70 moves the point of action F0 until it reaches a determinable rearward limit position. The rearward limit position is determined by the maximum possible steering angle of each of the outboard motors 4L and 4R. The information is stored in a memory (not shown) or the like.

[0070] After the point of application F0 reaches the rearward limit position, the controller 70 increases the propulsive forces of the outboard motors 4L, 4R as the required propulsive force increases.

[0071] Here, one of the outboard motors 4L, 4R is the outboard motor that exerts a propulsive force of the forward direction component in the fore-and-aft direction, and is called the "forward outboard motor." The other of the outboard motors 4L, 4R is the outboard motor that exerts a propulsive force of the reverse direction component in the fore-and-aft direction, and is called the "reverse outboard motor." In the example shown in Figures 7(a) to (d), since the boat is moving laterally to the right, the outboard motor 4L is the forward outboard motor, and the outboard motor 4R is the reverse outboard motor.

[0072] Normally, the upper limit (maximum) thrust force that the outboard motors 4L and 4R can actually generate is smaller when they are the outboard motors responsible for reverse drive than when they are the outboard motors responsible for forward drive. This is because the engine speed must be kept within a range in which cavitation does not occur when generating thrust force that includes a reverse component. Therefore, when increasing the thrust force of the outboard motors 4L and 4R, attention must be paid to the upper limit thrust force of the outboard motor responsible for reverse drive.

[0073] FIG. 7(c) shows a state in which the point of application F0 has reached the determinable rearward limit position, and the thrust of the outboard motor in charge of reverse drive has reached the upper limit thrust.

[0074] In this embodiment, in the process in which the required propulsive force increases after the start of the parallel movement, priority is given to moving the point of application F0 to the rearmost limit position, and the propulsive forces of the outboard motors 4L, 4R are increased after the point of application F0 reaches the rearmost limit position (first method). However, the order is not limited to the first method, and other methods, such as the following second and third methods, may be adopted.

[0075] First, in the second method, the thrust of the outboard motors 4L, 4R may be increased first, and the point of application F0 may be moved to the rearward limit position after the thrust of the outboard motor in charge of reverse drive reaches the upper limit thrust. Note that increasing the thrust of the outboard motors 4L, 4R and moving the point of application F0 rearward may be performed in parallel.

[0076] In the third method, the position of the point of application F0 may be moved rearward in accordance with the elapsed time after the start of the parallel movement, regardless of whether the required propulsive force increases. In this case, the controller 70 controls the propulsive force of each of the outboard motors 4L, 4R to be increased or decreased, taking into consideration the position of the point of application F0 that changes over time and the required propulsive force that changes. In this case, the relationship between the timing at which the point of application F0 reaches the rear limit position and the timing at which the propulsive force of the outboard motor in charge of reverse movement reaches the upper limit propulsive force cannot be uniformly determined.

[0077] Therefore, during the parallel movement, the controller 70 either moves the position of the point of application F0 rearward or increases the thrust of each of the outboard motors 4L, 4R as the required thrust increases. Regardless of which method is adopted, as the required thrust increases, the state shown in Figure 7(c) is reached. Thereafter, in order to improve the efficiency of the lateral movement, the controller 70 transitions to control as shown in Figure 7(d) as the required thrust increases.

[0078] 7(c), if the required propulsive force increases, the controller 70 increases only the propulsive force of the outboard motor in charge of forward movement. That is, when the position of the point of application F0 reaches the rear limit position and the propulsive force of the outboard motor in charge of reverse movement reaches the upper limit propulsive force during translation, the controller 70 as a control unit increases the propulsive force of the outboard motor in charge of forward movement.

[0079] If the point of application F0 is maintained at the rearmost position and the thrust of the propulsion unit in charge of forward movement is increased while maintaining the thrust of the propulsion unit in charge of reverse movement at the upper limit thrust, the resultant force FS will have a forward component (Figure 7(d)). In other words, the direction of the resultant force FS will be diagonally forward to the right. If this continues, the hull 2 ​​will propel forward and turn counterclockwise. Therefore, the controller 70 uses compensation control to apply the motor thrust force TF from the trolling motor 5 so as to cancel these out.

[0080] For example, as shown in Fig. 7(d), the motor propulsive force TF is set to a propulsive force of a direction and magnitude that cancels out the forward component of the resultant force FS and the turning component due to the resultant force FS. As a result, the propulsive force to the right acting on the hull 2 ​​increases further from the state shown in Fig. 7(c). Therefore, the hull 2 ​​moves parallel to the right at a speed according to the increase in the required propulsive force, without moving fore-aft or turning.

[0081] Similarly, in the case of parallel movement in which the target direction is diagonally forward to the right (Figures 7(e) to (h)), the controller 70 applies a resultant force FS in the target direction according to the required propulsive force to the point of action F0, which is determined based on the target direction and the required propulsive force, and in parallel therewith performs compensation control by the trolling motor 5.

[0082] During translation diagonally forward to the right, the direction of the resultant force FS and the motor thrust force TF is diagonally forward to the right until the point of action F0 reaches the rearmost position and the thrust force of the outboard motor in reverse reaches the upper limit thrust (from the state shown in FIG. 7(e) to the state shown in FIG. 7(g)). Their magnitudes change as needed.

[0083] Then, after the state shown in Fig. 7(g) is reached, the controller 70 maintains the point of application F0 at the rear limit position, and increases the thrust of the forward propulsion unit while maintaining the thrust of the reverse propulsion unit at the upper limit thrust. In this case, the forward component of the resultant force FS becomes larger (Fig. 7(h)). Therefore, the controller 70 applies a motor thrust force TF of a magnitude that cancels out the component of the resultant force FS in the direction perpendicular to the target direction and the turning component due to the resultant force FS.

[0084] As a result, the propulsive force acting on the hull 2 ​​in the target direction increases further from the state shown in Figure 7(g). Therefore, the hull 2 ​​moves parallel to the target direction at a speed according to the increase in the required propulsive force, without moving in a direction perpendicular to the target direction or turning.

[0085] 8 is a flowchart of the parallel movement mode processing. This processing is realized by the CPU 71 expanding a program stored in the ROM 72 into the RAM 73 and executing it. This processing is started, for example, when an instruction to start the parallel movement mode is given. When an instruction for parallel movement is acquired or when it is determined that a parallel movement is to be performed, the instruction to start the parallel movement mode is given. The "instruction for parallel movement" is input, for example, by a setting operator or an input operator in the various operators 16. "When it is determined that a parallel movement is to be performed" includes a case where the controller 70 determines that a parallel movement operation is necessary during the automatic ship maneuvering mode.

[0086] When the parallel movement mode process is started, the controller 70 controls the steering angles of the outboard motors 4L, 4R so that the point of application F0 of the resultant force FS is at the standby position.

[0087] In step S101, the controller 70 executes other processes, such as terminating this process if there is an instruction to terminate the translation mode.

[0088] In step S102, the controller 70 acquires steering command contents according to the vessel maneuvering mode from operation of the stick portion 13b of the joystick 13 or operation of the switches 63, 64, paddle portions 67, 68, etc. of the steering wheel 11. As described above, the steering command contents include a target direction and a required propulsive force.

[0089] In step S103, the controller 70 determines whether the point of application F0 has reached the rear limit position and the thrust of the reverse propulsion machine has reached the upper limit thrust. Whether the thrust of the reverse propulsion machine has reached the upper limit thrust may be determined, for example, from the engine speed. Alternatively, it may be determined that the upper limit thrust has been reached when a command value to the engine 84 exceeds a certain predetermined value. If the point of application F0 has not reached the rear limit position or the thrust of the reverse propulsion machine has not reached the upper limit thrust, the controller 70 proceeds to step S104.

[0090] In step S104, the controller 70 executes propulsion control. That is, as described above, the controller 70 moves the point of application F0 to the rear limit position in response to an increase in the required propulsive force by the first method, and then increases the propulsive forces of the outboard motors 4L, 4R. Alternatively, the controller 70 controls the outboard motors 4L, 4R by the second method or the third method. Furthermore, in parallel with the first, second, or third method, the controller 70 executes compensation control by the trolling motor 5.

[0091] In step S105, the controller 70 executes other controls. For example, when a turning command is issued or a situation occurs in which turning is necessary, a corresponding control process is executed. This control process will be described later with reference to Figs. 9 to 11. After step S105, the controller 70 returns to step S101.

[0092] If the result of the determination in step S103 is that the point of application F0 has reached the rearward limit position and the thrust of the reverse propulsion unit has reached the upper limit thrust, the controller 70 executes step S106.

[0093] In step S106, the controller 70 increases the thrust of the outboard motor in charge of forward movement in response to the increase in the required thrust. In parallel with this, compensation control by the trolling motor 5 is also performed. This allows the hull 2 ​​to move parallel to the water efficiently without turning its head. After step S106, the controller 70 proceeds to step S105.

[0094] Although not shown, the vessel 1 has a functional block for realizing the parallel movement mode processing (FIG. 8). The functional units included in the functional block include an acquisition unit and a control unit. The functions of these functional units are realized mainly by cooperation between the CPU 71, ROM 72, RAM 73, sensors 15, 55, 60, 83, 86, 87, etc.

[0095] 9 to 11, examples of "other control" executed in step S105 will be described. It is assumed that other control is executed when a command to turn is input by twisting the stick unit 13b or rotating the wheel unit 43, or when the controller 70 determines that turning is necessary during automatic ship steering mode.

[0096] 9 to 11 show an example of a transition when the stick portion 13b is twisted in the translation mode in the joystick mode. In each figure, for the motor driving force TF and the resultant force FS, the thin arrow indicates the driving force before the stick portion 13b is twisted, and the thick arrow indicates the driving force after the stick portion 13b is twisted. For convenience of explanation, it is assumed in FIGS. 9 to 11 that the target direction and the required driving force do not change.

[0097] 9(a) and (b) are transition diagrams (due to the processing of S105 in the loop of S103→S104→S105) at the stage when the point of action F0 has not reached the rear limit position or the thrust of the reverse propulsion unit has not reached the upper limit thrust.

[0098] The state shown in Fig. 9(a) is the same as the state shown in Fig. 7(b), and in this state, the stick portion 13b is not twisted. Fig. 9(b) is a state diagram when the stick portion 13b is twisted in the right rotation direction.

[0099] When the stick portion 13b is twisted in the right rotation direction from the state shown in FIG. 9(a), the controller 70 moves the point of action F0 closer to the center of gravity G and increases the motor thrust force TF (FIG. 9(b)). Moving the point of action F0 closer to the center of gravity G reduces the left turning component due to the resultant force FS. Increasing the motor thrust force TF increases the right turning component. As a result, the resultant force FS and the motor thrust force TF combine to produce a right turning component, and therefore the hull 2 ​​moves laterally to the right while turning in the right direction.

[0100] In this manner, the outboard motors 4L, 4R and the trolling motor 5 are controlled to add a necessary turning component while maintaining parallel movement in the target direction.

[0101] When the target direction is the left direction and the stick portion 13b is twisted in the left rotation direction, it can be understood that the left-right direction is reversed with respect to FIGS. 9(a) and (b).

[0102] 10 and 11 are transition diagrams after the point of application F0 reaches the rear limit position and the thrust of the reverse propulsion unit reaches the upper limit thrust (by the process of S105 in the loop of S103 → S106 → S105).

[0103] The states shown in Figs. 10(a) and 11(a) are the same as the state shown in Fig. 7(d), and in this state the stick portion 13b is not twisted.

[0104] When the stick section 13b is twisted in the right rotation direction from the state shown in Fig. 10(a), the controller 70 changes the direction of the motor thrust force TF in a direction that increases the right turning component, as shown in Fig. 10(b). Because a component in the fore-aft direction is generated by changing the direction of the motor thrust force TF, the controller 70 changes the direction of the resultant force FS in a direction to cancel this (reducing the thrust force of the outboard motor in charge of forward movement). As a result, the resultant force FS and the motor thrust force TF together generate a right turning component, and therefore the hull 2 ​​moves laterally to the right while turning in the right rotation direction.

[0105] When the stick section 13b is further twisted in the right rotation direction from the state shown in Fig. 10(b), the controller 70 increases the motor thrust force TF to increase the right turning component, as shown in Fig. 10(c). In parallel with this, the controller 70 moves the point of action F0 closer to the center of gravity G to reduce the left turning component. The resultant force FS and the motor thrust force TF combined increase the right turning component, and the hull 2 ​​moves laterally to the right while turning in the right rotation direction.

[0106] In this way, when the turning direction in response to the turning command is the same as the component of the target direction in the left-right direction, the trolling motor 5 is controlled to move the point of action F0 closer to the center of gravity G and to add the necessary turning component while maintaining parallel movement toward the target direction.

[0107] When the target direction is the left direction and the stick portion 13b is twisted in the left rotation direction, it can be understood that the left-right direction is reversed with respect to FIGS. 10(a) to (c).

[0108] When the stick 13b is twisted counterclockwise from the state shown in Fig. 11(a), the controller 70 changes the direction of the motor thrust force TF to a direction that increases the counterclockwise turning component (direction that decreases the clockwise turning component) as shown in Fig. 11(b). At this time, the direction and magnitude of the motor thrust force TF are controlled so that the forward / backward component of the motor thrust force TF does not change. Note that the resultant force FS does not change.

[0109] When the stick section 13b is further twisted in the counterclockwise direction from the state shown in FIG. 11(b), the controller 70 changes the direction of the motor thrust force TF to a direction that increases the counterclockwise turning component (direction that decreases the clockwise turning component) as shown in FIG. 11(c). At this time, the direction and magnitude of the motor thrust force TF are controlled so that the longitudinal component of the motor thrust force TF does not change. In the example shown in FIG. 11(c), the motor thrust force TF has a component in the left lateral direction. Note that the resultant force FS does not change. Therefore, the hull 2 ​​moves laterally to the right while turning in the counterclockwise direction.

[0110] In this way, when the turning direction in response to the turning command is opposite to the direction of the component in the left or right direction that the target direction has, the trolling motor 5 is controlled to maintain the resultant force FS at the point of action F0 as it is and to add the necessary turning component while maintaining parallel movement toward the target direction.

[0111] When the target direction is the left direction and the stick portion 13b is twisted in the right rotation direction, it can be understood that the left-right direction is reversed with respect to FIGS. 11(a) to (c).

[0112] When the wheel portion 43 is rotated in the parallel movement mode in the drive mode, other controls (step S105) are also applied in the same manner as when the stick portion 13b is twisted.

[0113] According to this embodiment, the controller 70 controls the outboard motors 4L, 4R to apply a resultant force FS to the point of application F0 determined based on the target direction and the required propulsive force during translation, and controls the trolling motor 5 to apply a motor propulsive force TF to offset the turning component of the resultant force FS and the component in the direction perpendicular to the target direction. The controller 70 moves the position of the point of application F0 rearward or increases the resultant force FS as the required propulsive force increases during translation, and increases the propulsive force of the forward propulsion unit when the point of application F0 reaches the rear limit position and the propulsive force of the reverse propulsion unit reaches the upper limit propulsive force. By using the trolling motor 5 in combination, the translation component can be increased while suppressing the component in the unnecessary direction. This improves the performance of translation.

[0114] Furthermore, if a command to turn is received during translation or if it is determined that a turn is to be performed, the outboard motors 4L, 4R and the trolling motor 5 are controlled to add a necessary turning component while maintaining translation in the target direction (FIGS. 9 to 11). This makes it possible to achieve turning while maintaining efficient translation.

[0115] The number of propulsion units arranged at the stern 2B and acting on the resultant force FS may be three or more. When there are three or more propulsion units, the number of outboard motors in charge of astern may be two or more.

[0116] In relation to the application of the present invention, the propulsion unit disposed at a predetermined position in front of the stern 2A is not limited to an electric propulsion unit such as the trolling motor 5, but may be an engine-type propulsion unit including an outboard motor. The propulsion unit disposed at the stern 2A is not limited to the outboard motor 4, but may be any of an inboard motor, an inboard-outboard motor, and a jet boat, and may be an electric type instead of an engine type.

[0117] The present invention can also be realized by supplying a program that realizes one or more of the functions of the above-mentioned embodiments to a system or device via a network or a non-transitory storage medium, and having one or more processors of a computer in the system or device read and execute the program. The above program and the storage medium that stores the above program constitute the present invention. The present invention can also be realized by a circuit (e.g., ASIC) that realizes one or more of the functions.

[0118] The present invention has been described above in detail based on its preferred embodiments, but the present invention is not limited to these specific embodiments, and various forms that do not deviate from the gist of the present invention are also included in the present invention. [Explanation of symbols]

[0119] 5 Trolling motor, 4L, 4R Outboard motor, 70 Controller, FS Resultant force, TF Motor propulsion force, F0 Point of application

Claims

1. a plurality of first propulsion units disposed at the stern of the hull and capable of being steered; a steerable second propulsion unit disposed at a predetermined position forward of the stern of the hull; an acquisition unit that acquires a target direction and a required propulsive force when an instruction for parallel movement is acquired or when it is determined that parallel movement is to be performed; a control unit that determines a point of application of a resultant force of propulsive forces to be applied to the hull by each of the multiple first propulsors based on the target direction and the required propulsive force obtained during translational movement, and controls the multiple first propulsors to apply a resultant force in the target direction corresponding to the required propulsive force to the determined point of application, and controls the second propulsors to apply a propulsive force to the predetermined position to offset a steering component of the resultant force with respect to the hull and a component in a direction perpendicular to the target direction, the control unit moves a position of the point of application rearward or increases the thrust of each of the plurality of first propulsion units in response to an increase in the required thrust during translation, The control unit increases the propulsion force of one of the plurality of first propulsors that is applying a propulsion force in a forward direction component when, during the parallel movement, the position of the point of application reaches a determinable rearward limit position and the propulsion force of one of the plurality of first propulsors that is applying a propulsion force in a reverse direction component reaches an upper limit propulsion force that can be generated.

2. 2. The vessel propulsion system according to claim 1, wherein the control unit moves the position of the center of application rearward in response to an increase in the required propulsive force after start of the parallel movement, and increases the propulsive force of each of the plurality of first propulsion units after the position of the center of application reaches the limit position.

3. 2. The marine vessel propulsion system according to claim 1, wherein the control unit increases the propulsive force of each of the plurality of first propulsion units in accordance with an increase in the required propulsive force after start of the parallel movement, and then moves the position of the center of application rearward after the propulsive force of the propulsion unit applying the propulsive force of the reverse direction component reaches the upper limit propulsive force.

4. The vessel propulsion system according to claim 1 , wherein the control unit moves the position of the point of application rearward in accordance with an elapsed time after the start of the translational movement.

5. 5. The marine vessel propulsion system according to claim 1, wherein, when a command to turn is obtained or when it is determined that a turning will be performed while the parallel movement is being performed, the control unit controls the plurality of first propulsion units and the second propulsion unit so as to add a necessary turning component while maintaining the parallel movement toward the target direction.

6. 6. The marine vessel propulsion system according to claim 5, wherein, when the target direction and the required propulsive force do not change and the turning direction in response to the instruction is the same as a component of a left-right direction that the target direction has, the control unit controls the second propulsion unit to move the point of action closer to a turning center of the hull and add a required turning component while maintaining parallel movement toward the target direction.

7. 6. The marine vessel propulsion system according to claim 5, wherein, when the target direction and the required propulsive force do not change and the turning direction in response to the instruction is opposite to a left / right direction component that the target direction has, the control unit controls the second propulsion unit to maintain the resultant force on the point of application as it is and to add a required turning component while maintaining parallel movement toward the target direction.

8. The vessel propulsion system according to claim 1 , wherein the predetermined position is a bow.

9. The marine vessel propulsion system according to claim 1 , wherein the second propulsion device is a trolling motor.

10. The hull and A marine vessel comprising a marine vessel propulsion system according to any one of claims 1 to 9.

11. A control method for a marine vessel propulsion system having a plurality of steerable first propulsion units disposed at a stern of a hull, and a steerable second propulsion unit disposed at a predetermined position forward of the stern of the hull, the method comprising the steps of: When an instruction for parallel movement is obtained or when it is determined that parallel movement is to be performed, a target direction and a required propulsive force are obtained; determine a point of application of a resultant force of propulsive forces to be applied to the hull by each of the multiple first propulsors based on the target direction and the required propulsive force obtained during translation, and control the multiple first propulsors to apply a resultant force in the target direction corresponding to the required propulsive force to the determined point of application, and control the second propulsor to apply a propulsive force to the predetermined position to offset a steering component of the resultant force with respect to the hull and a component in a direction perpendicular to the target direction; during the translational movement, in response to an increase in the required thrust, a position of the center of application is moved rearward or a thrust of each of the plurality of first propulsors is increased; a control method for a marine vessel propulsion system, comprising: when, during parallel movement, the position of the point of application reaches a determinable rearward limit position and the propulsion force of one of the plurality of first propulsors that is applying a propulsion force in a reverse direction component reaches an upper limit of propulsion force that can be generated, increasing the propulsion force of one of the plurality of first propulsors that is applying a propulsion force in a forward direction component.

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