Ship propulsion system and ship

Abstract

To provide a ship propulsion system that can prevent a ship speed from becoming excessively low when performing control for adjusting the ship speed on the basis of information concerning vertical motion of a hull during waves.SOLUTION: A ship propulsion system 100 comprises a control part 14 which performs ship speed control during waves for adjusting a ship speed V on the basis of information concerning vertical motion of the ship speed V during waves. The control part 14 performs the ship speed control during waves so that the ship speed V becomes a preset prescribed lowest ship speed V0 or more in a ship speed control mode during waves for performing the ship speed control during waves.SELECTED DRAWING: Figure 4

Description

[Technical field]

[0001] The present invention relates to a boat propulsion system and a boat. [Background technology]

[0002] 2. Description of the Related Art Conventionally, there is known a ship propulsion system that performs control to adjust the ship speed based on information regarding the up and down movement of the ship's hull when waves are rough (see, for example, Patent Document 1).

[0003] The above-mentioned Patent Document 1 describes a ship operation control device (ship propulsion system) that performs control to adjust the ship speed based on information regarding the vertical movement of the hull during rough waves. The ship operation control device described in the above-mentioned Patent Document 1 detects the degree of shock the hull receives during a voyage using an acceleration detector that detects the acceleration in the vertical direction of the hull, etc., and decelerates the hull when the acceleration in the vertical direction of the hull detected by the acceleration detector exceeds a preset limit value. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Japanese Patent Application Publication No. 6-211190 Summary of the Invention [Problem to be solved by the invention]

[0005] However, the ship navigation control device described in the above Patent Document 1 decelerates the ship when the acceleration of the ship in the vertical direction, etc., detected by the acceleration detector exceeds a preset limit value. Therefore, when the ship continuously overcomes relatively large waves, the ship continues to be decelerated, and the ship speed may become excessively slow. If the ship speed becomes excessively slow, for example, the ship may become unable to plan or may become almost unable to move forward. For this reason, there is a demand for a ship propulsion system and a ship that can prevent the ship speed from becoming excessively slow while control is being performed to adjust the ship speed based on information on the vertical movement of the ship in rough waves.

[0006] The present invention has been made to solve the above-mentioned problems, and one object of the present invention is to provide a ship propulsion system and a ship that can prevent the ship speed from becoming excessively slow while control is being performed to adjust the ship speed based on information regarding the up and down movement of the hull in rough waves. [Means for solving the problem]

[0007] In order to achieve the above-mentioned object, a ship propulsion system according to a first aspect of the present invention comprises a propulsion unit provided on a hull, and a control unit configured to control the drive of the propulsion unit to adjust the ship speed, and which performs ship speed control in rough waves to adjust the ship speed based on information regarding the up and down movement of the hull when waves are occurring, and the control unit is configured to perform ship speed control in rough waves so that the ship speed becomes equal to or greater than a predetermined minimum ship speed that has been set in advance.

[0008] In the vessel propulsion system according to the first aspect of the present invention, as described above, the control unit is configured to perform vessel speed control in a vessel speed control mode in which vessel speed control in waves is performed, so that the vessel speed becomes equal to or higher than a predetermined minimum vessel speed set in advance. This allows vessel speed control in waves to be performed while maintaining the vessel speed at or higher than a predetermined minimum vessel speed set in advance in the vessel speed control mode in waves. As a result, it is possible to prevent the vessel speed from becoming excessively slow while performing control to adjust the vessel speed based on information regarding the vertical movement of the hull in waves. Note that in this specification, "vessel speed" is a broad concept that includes vessel speed replaced with the rotation speed of the drive source (engine, etc.) of the propulsion unit, vessel speed estimated using a global satellite positioning system or a sensor (water speed sensor, etc.) provided on the vessel, etc.

[0009] In the vessel propulsion system according to the first aspect, the control unit is preferably configured to perform vessel speed control in rough waves in the vessel speed control mode so that the vessel speed is equal to or greater than a minimum vessel speed set to be equal to or greater than the minimum speed at which the vessel can plan. With this configuration, vessel speed control in rough waves can be performed while maintaining the vessel speed at or greater than the minimum speed at which the vessel can plan. As a result, in the vessel speed control mode in rough waves, a state in which the vessel receives small resistance from the water due to the vessel planing is maintained, thereby improving fuel efficiency while vessel speed control in rough waves is performed. In addition, in the vessel speed control mode in rough waves, the vessel does not change between a non-planing state and a planing state, so that the narrowing of the vessel operator's visibility due to the rise of the bow when the vessel changes from a non-planing state to a planing state can be suppressed.

[0010] In the vessel propulsion system according to the first aspect, the control unit is preferably configured to perform notification control to notify the vessel helmsman that the vessel speed has reached the minimum vessel speed when the vessel speed reaches the minimum vessel speed in the wave vessel speed control mode. With this configuration, when the vessel speed reaches the minimum vessel speed in the wave vessel speed control mode, the vessel helmsman can be made aware that the vessel speed has reached the minimum vessel speed.

[0011] In the vessel propulsion system according to the first aspect, the control unit is preferably configured to perform vessel speed control in rough waves so that the change in vessel speed becomes larger when the vessel speed falls below a predetermined vessel speed threshold value that is a predetermined amount higher than the minimum vessel speed in the vessel speed control mode. With this configuration, the change in vessel speed in the vessel speed control in rough waves can be made larger when the vessel speed falls below a vessel speed threshold value that is relatively close to the minimum vessel speed in the vessel speed control mode, so that the vessel speed can be increased relatively quickly in a situation in which the vessel speed is relatively close to the minimum vessel speed in the vessel speed control mode and it is desired to increase the vessel speed quickly.

[0012] In the configuration in which the control unit performs the ship speed control in rough waves so that the ship speed changes more significantly when the ship speed falls below a predetermined ship speed threshold in the ship speed control mode in rough waves, the control unit is preferably configured to perform the ship speed control in rough waves based on a value obtained by averaging information related to the up and down movement of the hull over a predetermined period, and is configured to shorten the predetermined period for averaging so that the ship speed changes more significantly when the ship speed falls below the ship speed threshold in the ship speed control mode in rough waves. With this configuration, the ship speed can be adjusted more frequently by the amount that the predetermined period for averaging is shortened, so that a configuration can be easily realized that can increase the ship speed relatively quickly in a situation in which the ship speed is relatively close to the minimum ship speed in the ship speed control mode in rough waves and it is desired to increase the ship speed quickly.

[0013] In this case, the control unit is preferably configured in the wavey ship speed control mode to set the predetermined period for averaging to a first period when the ship speed becomes equal to or less than a predetermined first ship speed threshold so that the ship speed changes significantly, and to set the predetermined period for averaging to a second period longer than the first period when the ship speed becomes equal to or greater than a predetermined second ship speed threshold higher than the first ship speed threshold after becoming equal to or less than the first ship speed threshold. With this configuration, the predetermined period for averaging can be kept at the relatively short first period until the ship speed becomes equal to or greater than the second ship speed threshold higher than the first ship speed threshold after becoming equal to or less than the first ship speed threshold, thereby preventing the predetermined period for averaging from switching excessively between the relatively short first period and the relatively long second period.

[0014] In the configuration in which the control unit performs the ship speed control in rough waves so that the ship speed changes more significantly when the ship speed falls below a predetermined ship speed threshold in the ship speed control mode in rough waves, the control unit is preferably configured to perform the ship speed control in rough waves based on a value obtained by averaging information on the vertical movement of the hull over a predetermined period, and is configured to change a weighting coefficient for adjusting the weighting of information on the vertical movement of the hull so that the weighting of the latest value of information on the vertical movement of the hull is greater than the weighting of information on the vertical movement of the hull other than the latest value, so that the ship speed changes more significantly when the ship speed falls below the ship speed threshold in the ship speed control mode in rough waves. With this configuration, the ship speed can be adjusted in the ship speed control in rough waves while more closely reflecting the most recent state of the hull, so that a configuration can be easily realized in which the ship speed can be increased relatively quickly in a situation in which the ship speed is relatively close to the minimum ship speed in the ship speed control mode in which it is desired to increase the ship speed quickly.

[0015] In this case, the control unit is preferably configured to set the weighting coefficient to a first weighting value so that when the ship speed becomes equal to or less than a predetermined first ship speed threshold, the change in ship speed becomes greater and the weighting of the latest value of information related to the vertical movement of the ship is greater than the weighting of information related to the vertical movement of the ship other than the latest value, and to change the weighting coefficient to a second weighting value so that when the ship speed becomes equal to or less than the first ship speed threshold and then equal to or more than a predetermined second ship speed threshold that is greater than the first ship speed threshold, the weighting coefficient is smaller than the weighting of the latest value of information related to the vertical movement of the ship compared to when the ship speed is equal to or less than the first ship speed threshold. With this configuration, the weighting coefficient can be kept at the relatively small first weighting value until the ship speed becomes equal to or more than a second ship speed threshold that is greater than the first ship speed threshold after becoming equal to or less than the first ship speed threshold, thereby preventing the weighting coefficient from switching excessively between the relatively small first weighting value and the relatively small second weighting value.

[0016] In the configuration in which the control unit performs the ship speed control in rough waves so that the ship speed changes more significantly when the ship speed falls below a predetermined ship speed threshold in the ship speed control mode in rough waves, the control unit is preferably configured to perform the ship speed control in rough waves based on a value obtained by averaging information related to the up and down movement of the hull over a predetermined period, and is configured to reduce the parameter for averaging so that the ship speed changes more significantly when the ship speed falls below the ship speed threshold in the ship speed control mode in rough waves. With this configuration, the ship speed can be adjusted more frequently by the parameter for averaging, so that a configuration can be easily realized that can increase the ship speed relatively quickly in a situation in which the ship speed is relatively close to the minimum ship speed in the ship speed control mode in rough waves and it is desired to increase the ship speed quickly.

[0017] In this case, the control unit is preferably configured in the rough ship speed control mode to set the parameter to be averaged to a first parameter value so that the change in ship speed becomes larger when the ship speed becomes equal to or less than a predetermined first ship speed threshold, and to set the parameter to be averaged to a second parameter value larger than the first parameter value when the ship speed becomes equal to or greater than a predetermined second ship speed threshold value larger than the first ship speed threshold after becoming equal to or less than the first ship speed threshold. With this configuration, the parameter to be averaged can be kept at the relatively small first parameter value until the ship speed becomes equal to or greater than the second ship speed threshold value larger than the first ship speed threshold after becoming equal to or less than the first ship speed threshold, thereby preventing the parameter to be averaged from switching excessively between the relatively small first parameter value and the relatively large second parameter value.

[0018] In the configuration in which the control unit performs ship speed control in rough waves so that the change in ship speed becomes larger when the ship speed becomes equal to or lower than a predetermined ship speed threshold in the ship speed control in rough waves mode, the control unit is preferably configured to increase the maximum value of the ship speed change rate so that the change in ship speed becomes larger when the ship speed becomes equal to or lower than the ship speed threshold in the ship speed control in rough waves mode. With this configuration, the ship speed change rate in the ship speed control in rough waves can be increased by the amount of the increase in the maximum value of the ship speed change rate, so that a configuration can be easily realized that can increase the ship speed relatively quickly in a situation in which the ship speed in the ship speed control in rough waves mode is relatively close to the minimum ship speed and it is desired to increase the ship speed quickly.

[0019] In this case, the control unit is preferably configured in the wavey ship speed control mode to set the maximum value of the ship speed change rate to a first change rate maximum value so that the ship speed changes more significantly when the ship speed becomes equal to or less than a predetermined first ship speed threshold, and to set the maximum value of the ship speed change rate to a second change rate maximum value smaller than the first change rate maximum value when the ship speed becomes equal to or greater than a predetermined second ship speed threshold value larger than the first ship speed threshold after becoming equal to or less than the first ship speed threshold. With this configuration, the maximum value of the ship speed change rate can be kept at the relatively small first change rate maximum value until the ship speed becomes equal to or greater than the second ship speed threshold value larger than the first ship speed threshold, thereby preventing the maximum value of the ship speed change rate from switching excessively between the relatively small first change rate maximum value and the relatively large second change rate maximum value.

[0020] In the vessel propulsion system according to the first aspect, the control unit is preferably configured to control the vessel speed in rough waves based on a moving average value obtained by averaging information related to the vertical movement of the hull over a predetermined period of time. With this configuration, vessel speed control in rough waves can be performed with high accuracy based on information related to the vertical movement of the hull that reflects the ever-changing state of the hull, unlike when vessel speed control in rough waves is performed based on an averaged value that is not a moving average value.

[0021] In the configuration in which the control unit performs the notification control, preferably, the control unit is further configured to include an operation unit that accepts operation by the vessel operator, and the control unit is configured to perform notification control when the vessel speed becomes the minimum vessel speed in the wave vessel speed control mode, and to change the minimum vessel speed when the vessel operator operates the operation unit to change the minimum vessel speed. With this configuration, when the vessel operator recognizes that the vessel speed has become the minimum vessel speed due to the notification control and wishes to temporarily change the minimum vessel speed, the minimum vessel speed can be changed by operating the operation unit to change the minimum vessel speed.

[0022] In the configuration in which the control unit changes the minimum boat speed when the helmsman operates to change the minimum boat speed in the wave-induced boat speed control mode, the control unit is preferably configured to perform notification control when the boat speed becomes the minimum boat speed in the wave-induced boat speed control mode, and to increase the minimum boat speed when the helmsman operates the operation unit to increase the minimum boat speed. With this configuration, when the helmsman recognizes that the boat speed has become the minimum boat speed due to the notification control and wishes to temporarily increase the minimum boat speed, he or she can increase the minimum boat speed by operating the operation unit to increase the minimum boat speed.

[0023] In the configuration in which the control unit changes the minimum boat speed when the operator operates to change the minimum boat speed in the rough sea boat speed control mode, the control unit is preferably configured to reset the changed minimum boat speed to an initial value when the power supply to the control unit is turned off or restarted in the rough sea boat speed control mode. This configuration makes it possible to prevent the minimum boat speed from remaining in a changed state.

[0024] In addition, in order to achieve the above-mentioned object, a ship according to a second aspect of the present invention comprises a propulsion unit provided on the hull, and a control unit configured to control the drive of the propulsion unit to adjust the ship speed, and to perform ship speed control in rough waves to adjust the ship speed based on information regarding the up and down movement of the hull when waves are occurring, and the control unit is configured to perform ship speed control in rough waves in a ship speed control mode in which ship speed control in rough waves is performed so that the ship speed becomes equal to or greater than a predetermined minimum ship speed that has been set in advance.

[0025] In the ship according to the second aspect of the present invention, as described above, the control unit is configured to perform ship speed control in rough waves in a ship speed control mode in which ship speed control in rough waves is performed, so that the ship speed becomes equal to or higher than a predetermined minimum ship speed that has been set in advance. This makes it possible to perform ship speed control in rough waves while maintaining the ship speed at or higher than a predetermined minimum ship speed, in the ship speed control mode in rough waves, as in the ship propulsion system according to the first aspect. As a result, as in the ship propulsion system according to the first aspect, it is possible to prevent the ship speed from becoming excessively slow while control is being performed to adjust the ship speed based on information related to the up and down movement of the hull in rough waves.

[0026] In the ship according to the second aspect, the control unit is preferably configured to perform ship speed control in rough waves in the ship speed control mode so that the ship speed is equal to or greater than a minimum ship speed set to be equal to or greater than the minimum speed at which the hull can plan. With this configuration, fuel efficiency can be improved while ship speed control in rough waves is being performed, as with the ship propulsion system according to the first aspect. Also, as with the ship propulsion system according to the first aspect, it is possible to prevent the visibility of the operator from being narrowed due to the rise of the bow when the hull changes from a non-planing state to a planing state.

[0027] In the ship according to the second aspect, the control unit is preferably configured to perform notification control to notify the ship helmsman that the ship speed has reached the minimum ship speed when the ship speed reaches the minimum ship speed in the wavey ship speed control mode. With this configuration, as with the ship propulsion system according to the first aspect, when the ship speed reaches the minimum ship speed in the wavey ship speed control mode, the ship helmsman can be made aware that the ship speed has reached the minimum ship speed.

[0028] In the ship according to the second aspect, the control unit is preferably configured to perform ship speed control in rough waves so that the ship speed changes more rapidly when the ship speed falls below a predetermined ship speed threshold value that is a predetermined amount higher than the minimum ship speed in the ship speed control mode. With this configuration, like the ship propulsion system according to the first aspect, in a situation where the ship speed is relatively close to the minimum ship speed in the ship speed control mode and it is desired to increase the ship speed quickly, the ship speed can be increased relatively quickly. Effect of the Invention

[0029] According to the present invention, as described above, it is possible to provide a ship propulsion system and a ship that can prevent the ship speed from becoming excessively slow while control is being performed to adjust the ship speed based on information regarding the up and down movement of the hull during rough waves. [Brief description of the drawings]

[0030] [Figure 1] 1 is a block diagram of a marine propulsion system according to an embodiment of the present invention; [Diagram 2] 1 is a schematic diagram of a watercraft according to an embodiment of the present invention; FIG. [Diagram 3] 1 is a side view showing a propulsion unit of a marine vessel propulsion system according to a preferred embodiment of the present invention. [Figure 4] FIG. 4 is a diagram showing a change in boat speed due to rough sea boat speed control in the boat propulsion system according to the embodiment of the present invention. [Diagram 5] FIG. 10 is a diagram for explaining adjustment of boat speed during rough sea boat speed control in the boat propulsion system according to one embodiment of the present invention. [Figure 6] FIG. 13 is a diagram showing a minimum vessel speed and a vessel speed threshold during vessel speed control in rough waves in the vessel propulsion system according to one embodiment of the present invention. [Figure 7] FIG. 2 is a diagram for explaining a first means of control for increasing the change in boat speed during rough boat speed control in the boat propulsion system according to a preferred embodiment of the present invention. [Figure 8]FIG. 11 is a diagram for explaining a second means of control for increasing the change in boat speed during rough boat speed control in the boat propulsion system according to a preferred embodiment of the present invention. [Figure 9] FIG. 11 is a diagram for explaining a third means of control for increasing the change in boat speed during rough boat speed control in the boat propulsion system according to a preferred embodiment of the present invention. [Figure 10] FIG. 11 is a diagram for explaining a fourth means of control for increasing the change in boat speed during rough boat speed control in the boat propulsion system according to a preferred embodiment of the present invention. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0031] DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, preferred embodiments of the present invention will be described with reference to the accompanying drawings.

[0032] A vessel propulsion system 100 and a vessel 110 according to a preferred embodiment of the present invention will be described with reference to FIGS.

[0033] (Ship propulsion system and overall configuration of the ship) As shown in Fig. 1, the vessel propulsion system 100 is provided on a vessel 110. The vessel propulsion system 100 is a system for propelling the vessel 110. The vessel 110 is a relatively small vessel used for, for example, sightseeing, fishing, and the like.

[0034] The vessel propulsion system 100 (vessel 110) includes a hull 10 and a propulsion unit 20. As shown in Fig. 2, the propulsion unit 20 is provided on the hull 10. Only one propulsion unit 20 is attached to the stern 11 of the hull 10. In other words, the propulsion unit 20 is an outboard motor.

[0035] (Hull configuration) As shown in FIG. 1, the vessel 10 includes an operation unit 13, a control unit 14, a display unit 15, an IMU (Inertial Measurement Unit) 16, and a GNSS (Global Navigation Satellite System) communication unit 17.

[0036] The operation unit 13 is configured to receive operations by a boat operator to steer (steer) the boat 110. The operation unit 13 includes a remote controller and a steering wheel.

[0037] The control unit 14 is configured to control an ECU (Engine Control Unit) 28 and an SCU (Steering Control Unit) 29 of the propulsion unit 20 based on operations on the operation unit 13. In other words, the control unit 14 is configured to control the drive of the propulsion unit 20 so as to adjust the boat speed V (see FIG. 4). The control unit 14 is a computer that includes an arithmetic device such as a CPU (Central Processing Unit), non-volatile memories such as a ROM (Read Only Memory) and a RAM (Random Access Memory), and the like.

[0038] The display unit 15 is configured to display information about the vessel 110. The information about the vessel 110 includes, for example, the vessel speed V (actual vessel speed) (see FIG. 5), the RPM of the engine 22 of the propulsion unit 20, the shift state of the propulsion unit 20, the navigation mode of the vessel 110, and the like. The navigation mode of the vessel 110 includes a vessel speed control mode in rough seas, which will be described later. The display unit 15 is, for example, a liquid crystal display. Note that the display unit 15 may be a touch panel capable of displaying buttons that accept operations by the vessel operator.

[0039] The IMU 16 includes a gyro, an accelerometer, etc. The IMU 16 is configured to be capable of detecting acceleration in the vertical direction, etc., of the hull 10. In other words, the IMU 16 is configured to be capable of detecting information Ia relating to the vertical movement of the hull 10. The control unit 14 acquires the information Ia relating to the vertical movement of the hull 10 detected by the IMU 16.

[0040] The GNSS communication unit 17, together with the GNSS satellites 121, constitutes a global satellite positioning system 120. The GNSS communication unit 17 is configured to be able to communicate with the GNSS satellites 121. The control unit 14 acquires the position information of the hull 10, the ship speed V (actual ship speed) (see FIG. 5 ), and the like, based on information communicated with the GNSS satellites 121 via the GNSS communication unit 17.

[0041] (Propulsion unit configuration) 3, the propulsion unit 20 includes a propulsion unit body 20a and a bracket 20b. The propulsion unit body 20a is attached to a transom 12 provided at the stern 11 of the hull 10 via the bracket 20b.

[0042] The propulsion unit 20 includes an engine 22 that drives a propeller 21 that generates thrust. In other words, the propulsion unit 20 is an engine-type outboard motor configured to drive the propeller 21 with the engine 22. Specifically, the propulsion unit body 20a includes the engine 22, a drive shaft 23, a gear unit 24, a propeller shaft 25, and the propeller 21. The engine 22 is an internal combustion engine that generates driving force. The driving force of the engine 22 is transmitted to the propeller 21 via the drive shaft 23, the gear unit 24, and the propeller shaft 25. The propeller 21 rotates in water by the transmitted driving force of the engine 22, thereby generating thrust for propelling the hull 10.

[0043] The propulsion unit main body 20a includes a shift actuator 26 that switches the shift state of the propulsion unit 20. The shift actuator 26 is configured to switch the shift state of the propulsion unit 20 between a forward state, a reverse state, and a neutral state by switching the meshing of the gear portion 24. The forward state is a state in which the driving force of the engine 22 is transmitted to the propeller 21 so as to generate thrust from the propeller 21 to the FWD side. The reverse state is a state in which the driving force of the engine 22 is transmitted to the propeller 21 so as to generate thrust from the propeller 21 to the BWD side. The neutral state is a state in which the driving force of the engine 22 is not transmitted to the propeller 21 so as not to generate thrust from the propeller 21.

[0044] The propulsion unit 20 includes a steering device 27 for changing the direction of the propulsive force generated by the propeller 21 so as to change the traveling direction of the hull 10. Specifically, the steering device 27 is provided on the bracket 20b. The steering device 27 includes a steering shaft 27a extending in the vertical direction. The propulsion unit body 20a is configured to be rotatable in the left-right direction with respect to the bracket 20b by the steering device 27 around the steering shaft 27a as the center of rotation. When the propulsion unit body 20a rotates in the left-right direction around the steering shaft 27a as the center of rotation, the orientation of the propeller 21 also rotates in the left-right direction. This changes the direction of the propulsive force generated by the propeller 21. In other words, the propulsion unit 20 is steered.

[0045] As shown in Fig. 1, the propulsion unit 20 includes an ECU 28 and an SCU 29. The ECU 28 is configured to control the drive of the engine 22 and the drive of the shift actuator 26 based on control by the control unit 14. That is, the control unit 14 controls the drive of the engine 22 via the ECU 28 so as to change the propulsive force by the propeller 21, thereby controlling the boat speed V (see Fig. 4). The SCU 29 is configured to control the drive of the steering device 27 based on control by the control unit 14. Each of the ECU 28 and the SCU 29 is a computer including an arithmetic device such as a CPU, non-volatile memories such as a ROM and a RAM, and the like.

[0046] (Ship speed control in rough waves) As shown in Fig. 4, the vessel propulsion system 100 (see Fig. 1) (vessel 110 (see Fig. 1)) is configured to adjust the vessel speed V during rough waves so that impacts on the vessel 10 caused by the vessel 10 riding over waves are kept within a preset range. Specifically, the control unit 14 (see Fig. 1) performs vessel speed control during rough waves, which adjusts the vessel speed V based on information Ia (see Fig. 1) relating to the up and down movement of the vessel 10. The information Ia relating to the up and down movement of the vessel 10 is, for example, the acceleration of the vessel 10 in the vertical direction.

[0047] In detail, as shown in Fig. 5, the control unit 14 (see Fig. 1) first acquires information Ia (see Fig. 1) relating to the up and down movement of the hull 10 from the IMU 16 (see Fig. 1). The control unit 14 then calculates a target ship speed VT, which is a target value for the ship speed V, based on the acquired information Ia relating to the up and down movement of the hull 10, the ship speed V (actual ship speed) acquired by the global satellite positioning system 120, and information Ib for keeping the impact on the hull 10 within a preset range. The control unit 14 then performs feedback control to adjust the ship speed V based on the difference between the calculated target ship speed VT and the acquired ship speed V (actual ship speed).

[0048] The control unit 14 (see FIG. 1) is configured to control the ship speed in rough waves based on a moving average value obtained by averaging information Ia relating to the up and down movement of the hull 10 over a predetermined period P. Specifically, the control unit 14 (see FIG. 1) calculates a target ship speed VT based on a moving average value obtained by averaging the acquired information Ia relating to the up and down movement of the hull 10 over a predetermined period P, a moving average value obtained by averaging the ship speed V (actual ship speed) over the predetermined period P, and information Ib for keeping the impact on the hull 10 within a preset range, so that the impact on the hull 10 caused by the hull 10 riding over waves in rough waves falls within a preset range.

[0049] As shown in Fig. 4, the control unit 14 (see Fig. 1) performs vessel speed control in rough waves when the navigation mode of the vessel 110 (see Fig. 1) is a vessel speed control mode in rough waves that performs vessel speed control in rough waves. When the operator operates the operation unit 13 to set the navigation mode of the vessel 110 to the vessel speed control mode in rough waves, the control unit 14 sets the navigation mode of the vessel 110 to the vessel speed control mode in rough waves. Note that in Fig. 4, the state in which the navigation mode of the vessel 110 is the vessel speed control mode in rough waves and the state in which the navigation mode of the vessel 110 is not the vessel speed control mode in rough waves are shown as vessel speed control mode in rough waves ON and vessel speed control mode in rough waves OFF, respectively.

[0050] (Minimum ship speed setting during ship speed control in rough waves) As shown in Fig. 6, in the wavey vessel speed control mode, the control unit 14 is configured to perform wavey vessel speed control so that the vessel speed V becomes equal to or greater than a predetermined minimum vessel speed V0 that has been set in advance. The predetermined minimum vessel speed V0 is set to be equal to or greater than the minimum speed at which the vessel 10 can plan. In other words, the control unit 14 is configured to perform wavey vessel speed control so that the vessel speed V becomes equal to or greater than the minimum vessel speed V0 that has been set to be equal to or greater than the minimum speed at which the vessel 10 can plan.

[0051] (Control to increase the change in ship speed during ship speed control in rough waves) In the rough sea ship speed control mode, when the ship speed V falls below a predetermined ship speed threshold VP that is a predetermined amount higher than the minimum ship speed V0, the control unit 14 is configured to perform rough sea ship speed control by the following four means so that the change in ship speed V becomes larger.

[0052] As shown in Fig. 7, as a first means of control for increasing the change in ship speed V during ship speed control in rough waves, the control unit 14 (see Fig. 1) is configured to reduce the predetermined period P for averaging processing so that the change in ship speed V increases when the ship speed V becomes equal to or lower than the ship speed threshold value VP (see Fig. 6) in the ship speed control mode in rough waves. Also, in the control for changing the predetermined period P for averaging processing by the control unit 14, a control hysteresis is set.

[0053] Specifically, in the rough boat speed control mode, the control unit 14 (see FIG. 1) first judges whether the boat speed V has become equal to or less than a predetermined first boat speed threshold VP1 (step S11). If the control unit 14 judges that the boat speed V has become equal to or less than the predetermined first boat speed threshold VP1, it sets the predetermined period P for averaging processing to the first period P1 so that the change in the boat speed V becomes large (step S12). The control unit 14 repeats the process of step S11 until it judges that the boat speed V has become equal to or less than the predetermined first boat speed threshold VP1. Note that, at the time of step S11, the boat speed V is assumed to be equal to or greater than a second boat speed threshold VP2, which will be described later.

[0054] Then, the control unit 14 (see FIG. 1) judges whether or not the vessel speed V becomes equal to or greater than a second vessel speed threshold VP2, which is greater than the first vessel speed threshold VP1, after becoming equal to or less than the first vessel speed threshold VP1 in the wavey vessel speed control mode (step S13). If the control unit 14 judges that the vessel speed V becomes equal to or greater than the second vessel speed threshold VP2 after becoming equal to or less than the first vessel speed threshold VP1, it sets the predetermined period P for averaging processing to a second period P2, which is greater than the first period P1 (step S14). The control unit 14 repeats step S13 until it judges that the vessel speed V becomes equal to or greater than the second vessel speed threshold VP2. After step S14, the control unit 14 returns to the processing of step S11.

[0055] As shown in Figure 8, as a second means of control for increasing the change in ship speed V during ship speed control in rough waves, the control unit 14 (see Figure 1) is configured to change a weighting coefficient K for adjusting the weighting of the information Ia relating to the vertical movement of the hull 10 when the ship speed V falls below a ship speed threshold VP (see Figure 6) in the wavey ship speed control mode, so that the change in ship speed V is increased when the ship speed V falls below a ship speed threshold VP (see Figure 6). In the control for changing the weighting coefficient K for adjusting the weighting of the information Ia relating to the vertical movement of the hull 10, a control hysteresis is set.

[0056] Specifically, in the wave-state vessel speed control mode, the control unit 14 (see FIG. 1) first judges whether the vessel speed V has become equal to or less than a predetermined first vessel speed threshold VP1 (step S21). If the control unit 14 judges that the vessel speed V has become equal to or less than the predetermined first vessel speed threshold VP1, the control unit 14 sets the weighting coefficient K to the first weighting value K1 so that the weighting of the latest value Ian of the information Ia relating to the vertical movement of the vessel 10 is greater than the weighting of the information other than the latest value Ian of the information Ia relating to the vertical movement of the vessel 10 so that the change in the vessel speed V is greater (step S22). The control unit 14 repeats the process of step S21 until it judges that the vessel speed V has become equal to or less than the predetermined first vessel speed threshold VP1. It is assumed that the vessel speed V is equal to or greater than the second vessel speed threshold VP2 at the time of step S21.

[0057] Then, in the wave-in-ship speed control mode, the control unit 14 (see FIG. 1) judges whether the ship speed V becomes equal to or greater than a second ship speed threshold VP2, which is greater than the first ship speed threshold VP1, after becoming equal to or less than the first ship speed threshold VP1 (step S23). If the control unit 14 judges that the ship speed V becomes equal to or greater than the second ship speed threshold VP2 after becoming equal to or less than the first ship speed threshold VP1, the control unit 14 changes the weighting coefficient K to a second weighting value K2 so that the weighting of the latest value Ian of the information Ia relating to the vertical movement of the hull 10 becomes smaller compared to when the ship speed V is equal to or less than the first ship speed threshold VP1 (step S24). The control unit 14 repeats step S23 until it judges that the ship speed V becomes equal to or greater than the second ship speed threshold VP2. After step S24, the control unit 14 returns to the process of step S21.

[0058] As shown in Figure 9, as a third means of control for increasing the change in ship speed V during ship speed control in rough waves, the control unit 14 (see Figure 1) is configured to reduce the parameter N for averaging so that the change in ship speed V increases when the ship speed V falls below the ship speed threshold VP (see Figure 6) in the ship speed control mode in rough waves. In the control for changing the parameter N for averaging, a control hysteresis is set.

[0059] Specifically, in the wave-state vessel speed control mode, the control unit 14 (see FIG. 1) first judges whether the vessel speed V has become equal to or less than a predetermined first vessel speed threshold VP1 (step S31). Then, when the control unit 14 judges that the vessel speed V has become equal to or less than the predetermined first vessel speed threshold VP1, it sets the parameter N to be averaged to the first parameter value N1 so that the change in the vessel speed V becomes larger (step S32). The control unit 14 repeats the process of step S31 until it judges that the vessel speed V has become equal to or less than the predetermined first vessel speed threshold VP1. Note that, at the time of step S31, the vessel speed V is assumed to be equal to or greater than the second vessel speed threshold VP2.

[0060] Then, the control unit 14 (see FIG. 1) judges whether or not the vessel speed V becomes equal to or greater than a second vessel speed threshold VP2 that is greater than the first vessel speed threshold VP1 after becoming equal to or less than the first vessel speed threshold VP1 in the wavey vessel speed control mode (step S33). If the control unit 14 judges that the vessel speed V becomes equal to or greater than the second vessel speed threshold VP2 after becoming equal to or less than the first vessel speed threshold VP1, it sets the parameter N to be averaged to a second parameter N2 that is greater than the first parameter N1 (step S34). The control unit 14 repeats step S33 until it judges that the vessel speed V becomes equal to or greater than the second vessel speed threshold VP2. After step S34, the control unit 14 returns to the process of step S31.

[0061] As shown in Figure 10, as a fourth means of control for increasing the change in ship speed V during ship speed control in rough waves, the control unit 14 (see Figure 1) is configured to increase the maximum value MM of the rate of change M of ship speed V so that the change in ship speed V becomes larger when the ship speed V becomes equal to or lower than the ship speed threshold value VP (see Figure 6) in the ship speed control mode in rough waves. In the control for changing the maximum value MM of the rate of change M of ship speed V, a control hysteresis is set.

[0062] Specifically, in the wave-state vessel speed control mode, the control unit 14 (see FIG. 1) first determines whether the vessel speed V has become equal to or less than a predetermined first vessel speed threshold VP1 (step S41). If the control unit 14 determines that the vessel speed V has become equal to or less than the predetermined first vessel speed threshold VP1, it sets the maximum value MM of the rate of change M of the vessel speed V to the first maximum rate of change MM1 so that the change in the vessel speed V becomes larger (step S42). The control unit 14 repeats the process of step S41 until it determines that the vessel speed V has become equal to or less than the predetermined first vessel speed threshold VP1. It is assumed that the vessel speed V is equal to or greater than the second vessel speed threshold VP2 at the time of step S41.

[0063] Then, in the wavey vessel speed control mode, the control unit 14 (see FIG. 1) judges whether the vessel speed V becomes equal to or greater than a predetermined second vessel speed threshold VP2 that is greater than the first vessel speed threshold VP1 after becoming equal to or less than the first vessel speed threshold VP1 (step S43). If the control unit 14 judges that the vessel speed V becomes equal to or greater than the second vessel speed threshold VP2 after becoming equal to or less than the first vessel speed threshold VP1, it sets the maximum value MM of the rate of change M of the vessel speed V to a second maximum rate of change MM2 that is smaller than the first maximum rate of change MM1 (step S44). The control unit 14 repeats step S43 until it judges that the vessel speed V becomes equal to or greater than the second vessel speed threshold VP2. After step S44, the control unit 14 returns to the processing of step S41.

[0064] (Notification control during ship speed control in rough waves) As shown in Fig. 6, the control unit 14 (see Fig. 1) is configured to perform notification control to notify the operator that the vessel speed V has reached the minimum vessel speed V0 when the vessel speed V reaches the minimum vessel speed V0 in the rough vessel speed control mode. For example, when the vessel speed V reaches the minimum vessel speed V0, the control unit 14 performs notification control such as control to display a message and a mark indicating that the vessel speed V has reached the minimum vessel speed V0 on the display unit 15 (see Fig. 1), control to output a sound indicating that the vessel speed V has reached the minimum vessel speed V0, and control to light or blink a lamp indicating that the vessel speed V has reached the minimum vessel speed V0.

[0065] The control unit 14 (see FIG. 1) is configured to perform notification control when the vessel speed V becomes the minimum vessel speed V0 in the wave vessel speed control mode, and to change the minimum vessel speed V0 when the vessel operator operates the operation unit 13 (see FIG. 1) to change the minimum vessel speed V0. Specifically, the control unit 14 (see FIG. 1) is configured to perform notification control when the vessel speed V becomes the minimum vessel speed V0 in the wave vessel speed control mode, and to increase the minimum vessel speed V0 when the vessel operator operates the operation unit 13 to increase the minimum vessel speed V0. The control unit 14 is configured to return the changed minimum vessel speed V0 to its initial value when the power of the control unit 14 is turned off or restarted.

[0066] [Effects of the embodiment] In this embodiment, the following effects can be obtained.

[0067] In this embodiment, as described above, the control unit 14 is configured to perform vessel speed control in rough waves in the vessel speed control mode in which vessel speed control in rough waves is performed so that the vessel speed V becomes equal to or higher than a predetermined minimum vessel speed V0 set in advance. This makes it possible to perform vessel speed control in rough waves while maintaining the vessel speed V at or higher than a predetermined minimum vessel speed V0 set in advance in the vessel speed control mode in rough waves. As a result, it is possible to prevent the vessel speed V from becoming excessively slow while control is being performed to adjust the vessel speed V based on information Ia relating to the up and down movement of the vessel speed V in rough waves.

[0068] In addition, in this embodiment, as described above, the control unit 14 is configured to perform the vessel speed control in the wave-time vessel speed control mode so that the vessel speed V is equal to or greater than the minimum vessel speed V0, which is set to be equal to or greater than the minimum speed at which the vessel 10 can plan. This allows the vessel speed control in the wave-time vessel speed control mode to be performed while maintaining the vessel speed V at or greater than the minimum speed at which the vessel 10 can plan. As a result, in the wave-time vessel speed control mode, the vessel speed V is maintained in a state in which the vessel 10 receives small resistance from the water due to the vessel 10 planing, thereby improving fuel efficiency while the vessel speed control in the wave-time is being performed. In addition, since the vessel speed V does not change between the non-planing state and the planing state, it is possible to suppress the narrowing of the vessel operator's visibility accompanying the rise of the bow when the vessel speed V changes from the non-planing state to the planing state.

[0069] In this embodiment, as described above, the control unit 14 is configured to perform notification control to notify the vessel operator that the vessel speed V has reached the minimum vessel speed V0 in the wavey vessel speed control mode when the vessel speed V reaches the minimum vessel speed V0. This allows the vessel operator to recognize that the vessel speed V has reached the minimum vessel speed V0 in the wavey vessel speed control mode when the vessel speed V reaches the minimum vessel speed V0.

[0070] Furthermore, in this embodiment, as described above, the control unit 14 is configured to perform vessel speed control in rough waves so as to increase the change in vessel speed V when the vessel speed V falls below a predetermined vessel speed threshold VP that is a predetermined amount higher than the minimum vessel speed V0 in the vessel speed control in rough waves mode. This makes it possible to increase the change in vessel speed V in the vessel speed control in rough waves when the vessel speed V falls below a vessel speed threshold VP that is relatively close to the minimum vessel speed V0 in the vessel speed control in rough waves mode, so that the vessel speed V can be increased relatively quickly in a situation in which the vessel speed V is relatively close to the minimum vessel speed V0 in the vessel speed control in rough waves mode and it is desired to increase the vessel speed V quickly.

[0071] Furthermore, in this embodiment, as described above, the control unit 14 is configured to perform ship speed control in rough waves based on a value obtained by averaging information Ia relating to the up and down movement of the hull 10 over a predetermined period P. The control unit 14 is configured to shorten the predetermined period P for averaging in the rough waves ship speed control mode so that the change in ship speed V becomes larger when the ship speed V becomes equal to or less than the ship speed threshold value VP. This allows ship speed V to be adjusted more frequently by the amount that the predetermined period P for averaging is shortened, so that a configuration can be easily realized that can increase ship speed V relatively quickly in a situation in which ship speed V is relatively close to minimum ship speed V0 in the rough waves ship speed control mode and it is desired to increase ship speed V quickly.

[0072] In this embodiment, as described above, the control unit 14 is configured to set the predetermined period P for averaging to the first period P1 so that the change in the vessel speed V becomes large when the vessel speed V becomes equal to or less than the first vessel speed threshold VP1 in the wavey vessel speed control mode, and to set the predetermined period P for averaging to the second period P2 longer than the first period P1 when the vessel speed V becomes equal to or greater than the second vessel speed threshold VP2 that is greater than the first vessel speed threshold VP1 after becoming equal to or less than the first vessel speed threshold VP1. This allows the predetermined period P for averaging to remain the relatively short first period P1 until the vessel speed V becomes equal to or greater than the second vessel speed threshold VP2 that is greater than the first vessel speed threshold VP1 after becoming equal to or less than the first vessel speed threshold, thereby preventing the predetermined period P for averaging from switching excessively between the relatively short first period P1 and the relatively long second period P2.

[0073] In this embodiment, as described above, the control unit 14 is configured to adjust the vessel speed V based on a value obtained by averaging the information Ia relating to the vertical movement of the vessel 10 over a predetermined period P. The control unit 14 is configured to change the weighting coefficient K for adjusting the weighting of the information Ia relating to the vertical movement of the vessel 10 when the vessel speed V becomes equal to or lower than the vessel speed threshold value VP in the vessel speed control mode in high waves, so that the weighting of the latest value Ian of the information Ia relating to the vertical movement of the vessel 10 is increased compared to the weighting of the information other than the latest value Ian of the information Ia relating to the vertical movement of the vessel 10, so that the change in the vessel speed V is large. As a result, the vessel speed V can be adjusted in the vessel speed control in high waves while more closely reflecting the most recent state of the vessel 10, so that a configuration can be easily realized that allows the vessel speed V to be increased relatively quickly in a situation in which the vessel speed V is relatively close to the minimum vessel speed V0 in the vessel speed control mode in high waves and it is desired to increase the vessel speed V quickly.

[0074] Furthermore, in this embodiment, as described above, the control unit 14 is configured in the wave-condition ship speed control mode to set the weighting coefficient K to the first weighting value K1 so that when the ship speed V becomes equal to or below a predetermined first ship speed threshold VP1, the change in ship speed V becomes larger and the weighting of the latest value Ian of the information Ia relating to the vertical movement of the hull 10 is greater than the weighting of the information Ia relating to the vertical movement of the hull 10 other than the latest value Ian, and to change the weighting coefficient K to the second weighting value K2 so that when the ship speed V becomes equal to or below the first ship speed threshold VP1 and then equal to or above a predetermined second ship speed threshold VP2 that is greater than the first ship speed threshold VP1, the weighting of the latest value Ian of the information Ia relating to the vertical movement of the hull 10 is smaller than when the ship speed V is equal to or below the first ship speed threshold VP1. This allows the weighting coefficient K to remain at the relatively small first weighting value K1 until the ship speed V becomes equal to or greater than the second ship speed threshold VP2, which is greater than the first ship speed threshold VP1, after the ship speed V becomes equal to or less than the first ship speed threshold VP1, thereby preventing the weighting coefficient K from switching excessively between the relatively small first weighting value K1 and the relatively small second weighting value K2.

[0075] In this embodiment, as described above, the control unit 14 is configured to perform ship speed control in rough waves based on a value obtained by averaging information Ia relating to the up and down movement of the hull 10 over a predetermined period P. The control unit 14 is configured to reduce the parameter N for averaging in the rough waves ship speed control mode so that the change in ship speed V becomes larger when the ship speed V falls below the ship speed threshold VP. This allows the ship speed V to be adjusted more frequently by the parameter N for averaging, and therefore makes it possible to easily realize a configuration that enables ship speed V to be increased relatively quickly in a situation in which ship speed V is relatively close to minimum ship speed V0 in the rough waves ship speed control mode and it is desired to increase ship speed V quickly.

[0076] In this embodiment, as described above, the control unit 14 is configured to set the parameter N to be averaged to the first parameter value N1 so that the change in the ship speed V becomes large when the ship speed V becomes equal to or less than the predetermined first ship speed threshold value VP1 in the wavey ship speed control mode, and to set the parameter N to be averaged to the second parameter value N2 larger than the first parameter value N1 when the ship speed V becomes equal to or greater than the predetermined second ship speed threshold value VP2 larger than the first ship speed threshold value VP1 after becoming equal to or less than the first ship speed threshold value VP1. This allows the parameter N to be averaged to remain the relatively small first parameter value N1 until the ship speed V becomes equal to or greater than the second ship speed threshold value VP2 larger than the first ship speed threshold value VP1 after becoming equal to or less than the first ship speed threshold value VP1, thereby preventing the parameter N to be averaged from switching excessively between the relatively small first parameter value N1 and the relatively large second parameter value N2.

[0077] Furthermore, in this embodiment, as described above, the control unit 14 is configured to increase the maximum value MM of the rate of change M of the vessel speed V so that the change in vessel speed V becomes larger when the vessel speed V becomes equal to or lower than the vessel speed threshold value VP in the vessel speed control mode in rough waves. This makes it possible to increase the rate of change of vessel speed V in vessel speed control in rough waves by the amount of the increase in the maximum value MM of the rate of change M of vessel speed V, so that a configuration can be easily realized that enables the vessel speed V to be increased relatively quickly in a situation in which the vessel speed V is relatively close to the minimum vessel speed V0 in the vessel speed control mode in rough waves and it is desired to increase the vessel speed V quickly.

[0078] In this embodiment, as described above, the control unit 14 is configured to set the maximum value MM of the rate of change M of the ship speed V to the first maximum value of change rate MM1 so that the change in the ship speed V becomes large when the ship speed V becomes equal to or less than the predetermined first ship speed threshold VP1 in the wave-state ship speed control mode, and to set the maximum value MM of the rate of change M of the ship speed V to the second maximum value of change rate MM2 smaller than the first maximum value of change rate MM1 when the ship speed V becomes equal to or greater than the predetermined second ship speed threshold VP2 larger than the first ship speed threshold VP1 after becoming equal to or less than the first ship speed threshold VP1. This allows the maximum value of the rate of change M of the ship speed V to remain at the relatively small first maximum value of change rate MM1 until the ship speed V becomes equal to or greater than the second ship speed threshold VP2 larger than the first ship speed threshold VP1 after becoming equal to or less than the first ship speed threshold VP1, thereby preventing the maximum value of the rate of change M of the ship speed V from switching excessively between the relatively small first maximum value of change rate MM1 and the relatively large second maximum value of change rate MM2.

[0079] Furthermore, in this embodiment, as described above, the control unit 14 is configured to control the ship speed in rough waves based on a moving average value obtained by averaging information Ia relating to the up and down movement of the hull 10 over a predetermined period P. This makes it possible to accurately control the ship speed in rough waves based on information Ia relating to the up and down movement of the hull 10 that reflects the state of the ship speed V, which changes from moment to moment, unlike when ship speed control in rough waves is performed based on an averaged value that is not a moving average value.

[0080] Furthermore, in this embodiment, as described above, the vessel propulsion system 100 (vessel 110) includes an operation unit 13 that receives operation by the vessel operator. The control unit 14 is configured to perform notification control when the vessel speed V becomes the minimum vessel speed V0 in the wave vessel speed control mode, and to change the minimum vessel speed V0 when the vessel operator operates the operation unit 13 to change the minimum vessel speed V0. As a result, when the vessel operator recognizes that the vessel speed V has become the minimum vessel speed V0 due to the notification control and wishes to temporarily change the minimum vessel speed V0, he or she can disable the minimum vessel speed V0 by operating the operation unit 13 to change the minimum vessel speed V0.

[0081] Furthermore, in this embodiment, as described above, the control unit 14 is configured to perform notification control when the vessel speed V becomes the minimum vessel speed V0 in the rough vessel speed control mode, and to increase the minimum vessel speed V0 when the vessel operator operates the operation unit 13 to increase the minimum vessel speed V0. As a result, when the vessel operator recognizes that the vessel speed V has become the minimum vessel speed V0 due to the notification control and wishes to temporarily increase the minimum vessel speed V0, the minimum vessel speed V0 can be increased by operating the operation unit 13 to increase the minimum vessel speed V0.

[0082] In this embodiment, as described above, the control unit 14 is configured to reset the changed minimum boat speed V0 to its initial value when the power supply to the control unit 14 is turned off or restarted in the rough boat speed control mode. This makes it possible to prevent the minimum boat speed V0 from remaining in a changed state.

[0083] [Variations] The embodiments disclosed herein should be considered to be illustrative and not restrictive in all respects. The scope of the present invention is indicated by the claims rather than the description of the above embodiments, and further includes all modifications (variations) within the meaning and scope of the claims.

[0084] For example, in the above embodiment, an example has been shown in which the control unit 14 is configured to return the changed minimum boat speed V0 to the initial value when the power supply of the control unit 14 is turned off or restarted in the rough boat speed control mode, but the present invention is not limited to this. In the present invention, the control unit may be configured to return the changed minimum boat speed to the initial value when the operator operates the operation unit to return the changed minimum boat speed to the initial value in the rough boat speed control mode.

[0085] In the above embodiment, an example was shown in which the control unit 14 is configured to perform notification control when the vessel speed V becomes the minimum vessel speed V0 in the wave vessel speed control mode, and to increase the minimum vessel speed V0 when the vessel operator operates the operation unit 13 to increase the minimum vessel speed V0, but the present invention is not limited to this. In the present invention, the control unit may be configured to perform notification control when the vessel speed becomes the minimum vessel speed in the wave vessel speed control mode, and to reduce the minimum vessel speed when the vessel operator operates the operation unit to reduce the minimum vessel speed.

[0086] In the above embodiment, an example was shown in which the control unit 14 is configured to perform notification control when the boat speed V becomes the minimum boat speed V0 in the wavey boat speed control mode, and to change the minimum boat speed V0 when the boat operator operates the operation unit 13 to change the minimum boat speed V0, but the present invention is not limited to this. In the present invention, the control unit may be configured to perform notification control when the boat speed becomes the minimum boat speed in the wavey boat speed control mode, and may not be configured to change the minimum boat speed. Also, the control unit may be configured to perform notification control when the boat speed becomes the minimum boat speed in the wavey boat speed control mode, and to disable the minimum boat speed when the boat operator operates the operation unit to disable the minimum boat speed.

[0087] In the above embodiment, an example has been shown in which the control unit 14 is configured to control the ship speed in rough waves based on a moving average value obtained by averaging information Ia relating to the vertical movement of the hull 10 over a predetermined period P, but the present invention is not limited to this. In the present invention, the control unit may be configured to control the ship speed in rough waves based on a value obtained by averaging information relating to the vertical movement of the hull other than the moving average value.

[0088] In the above embodiment, the control unit 14 is configured to set the maximum value MM of the rate of change M of the vessel speed V to the first maximum change rate MM1 so that the change in the vessel speed V becomes large when the vessel speed V becomes equal to or less than a predetermined first vessel speed threshold VP1 in the wave vessel speed control mode, and to set the maximum value MM of the rate of change M of the vessel speed V to the second maximum change rate MM2 smaller than the first maximum change rate MM1 when the vessel speed V becomes equal to or less than the first vessel speed threshold VP2 that is larger than the first vessel speed threshold VP1 after the vessel speed V becomes equal to or less than the first vessel speed threshold, but the present invention is not limited to this. In the present invention, the control unit may be configured to set the maximum value of the rate of change of the vessel speed to the first maximum change rate so that the change in the vessel speed becomes large when the vessel speed becomes equal to or less than a predetermined first vessel speed threshold in the wave vessel speed control mode, and to set the maximum value of the rate of change of the vessel speed to the second maximum change rate smaller than the first maximum change rate when the vessel speed becomes equal to or less than the first vessel speed threshold after the vessel speed becomes equal to or greater than the first vessel speed threshold. In other words, in the control for changing the maximum value of the rate of change of the boat speed, control hysteresis does not need to be set.

[0089] In the above embodiment, an example was shown in which the control unit 14 is configured to increase the maximum value MM of the rate of change M of the boat speed V so that the change in the boat speed V becomes larger when the boat speed V becomes equal to or less than the boat speed threshold value VP in the wavey boat speed control mode, but the present invention is not limited to this. In the present invention, the control unit may be configured not to change the maximum value of the rate of change of the boat speed even when the boat speed becomes equal to or less than the boat speed threshold value in the wavey boat speed control mode.

[0090] In the above embodiment, the control unit 14 is configured to set the parameter N to be averaged to the first parameter value N1 so that the change in the boat speed V becomes larger when the boat speed V becomes equal to or less than the first boat speed threshold value VP1 in the wavey boat speed control mode, and to set the parameter N to be averaged to the second parameter value N2 larger than the first parameter value N1 when the boat speed V becomes equal to or less than the first boat speed threshold value VP2, which is larger than the first boat speed threshold value VP1, after the boat speed V becomes equal to or less than the first boat speed threshold value VP1. However, the present invention is not limited to this. In the present invention, the control unit may be configured to set the parameter N to be averaged to the first parameter value so that the change in the boat speed becomes larger when the boat speed becomes equal to or less than the first boat speed threshold in the wavey boat speed control mode, and to set the parameter N to be averaged to the second parameter value larger than the first parameter value when the boat speed becomes equal to or less than the first boat speed threshold value after the boat speed becomes equal to or less than the first boat speed threshold value. In other words, control hysteresis may not be set in the control to change the parameter to be averaged.

[0091] In the above embodiment, the control unit 14 is configured to reduce the parameter N for averaging so that the change in the vessel speed V becomes larger when the vessel speed V becomes equal to or lower than the vessel speed threshold VP in the wavey vessel speed control mode, but the present invention is not limited to this. In the present invention, the control unit may be configured not to reduce the parameter N for averaging even when the vessel speed becomes equal to or lower than the vessel speed threshold in the wavey vessel speed control mode.

[0092] In addition, in the above embodiment, an example was shown in which the control unit 14 is configured to set the weighting coefficient K to a first weighting value K1 so that when the ship speed V becomes equal to or below a predetermined first ship speed threshold VP1 in the wave-condition ship speed control mode, the weighting coefficient K is increased compared to the weighting of the latest value Ian of the information Ia regarding the vertical movement of the hull 10 other than the latest value Ian, so that the change in the ship speed V is greater, and to change the weighting coefficient K to a second weighting value K2 so that when the ship speed V becomes equal to or below the first ship speed threshold VP1 and then equal to or above a predetermined second ship speed threshold VP2 that is greater than the first ship speed threshold VP1, the weighting coefficient K is increased compared to the case in which the ship speed V is equal to or below the first ship speed threshold VP1. However, the present invention is not limited to this. In the present invention, the control unit may be configured to set the weighting coefficient to a first weighting value so that when the ship speed becomes equal to or less than a predetermined first ship speed threshold in the wave-in-ship speed control mode, the weighting coefficient is increased in weighting of the most recent value of information related to the vertical movement of the hull compared to weighting of information related to the vertical movement of the hull other than the most recent value so that the change in ship speed becomes larger, and to change the weighting coefficient to a second weighting value so that when the ship speed becomes equal to or less than the first ship speed threshold and then exceeds the first ship speed threshold, the weighting coefficient is decreased in weighting of the most recent value of information related to the vertical movement of the hull compared to when the ship speed is equal to or less than the first ship speed threshold. In other words, control hysteresis may not be set in the control to change the weighting coefficient for adjusting the weighting of information related to the vertical movement of the hull.

[0093] In the above embodiment, an example was shown in which the control unit 14 is configured to change the weighting coefficient K for adjusting the weighting of the information Ia relating to the vertical movement of the hull 10 when the ship speed V falls below the ship speed threshold VP in the wave-induced ship speed control mode so that the weighting of the latest value Ian of the information Ia relating to the vertical movement of the hull 10 is greater than the weighting of the information Ia relating to the vertical movement of the hull other than the latest value Ian, so that the change in the ship speed V is greater, but the present invention is not limited to this. In the present invention, the control unit may be configured not to change the weighting coefficient for adjusting the weighting of the information relating to the vertical movement of the hull even when the ship speed falls below the ship speed threshold in the wave-induced ship speed control mode.

[0094] In the above embodiment, the control unit 14 is configured to set the predetermined period P for averaging to the first period P1 so that the change in the vessel speed V becomes large when the vessel speed V becomes equal to or less than the first vessel speed threshold VP1 in the wave vessel speed control mode, and set the predetermined period P for averaging to the second period P2 longer than the first period P1 when the vessel speed V becomes equal to or more than the second vessel speed threshold VP2 that is larger than the first vessel speed threshold VP1 after becoming equal to or less than the first vessel speed threshold VP1, but the present invention is not limited to this. In the present invention, the control unit may be configured to set the predetermined period for averaging to the first period so that the change in the vessel speed becomes large when the vessel speed becomes equal to or less than the first vessel speed threshold in the wave vessel speed control mode, and set the predetermined period for averaging to the second period longer than the first period when the vessel speed becomes equal to or less than the first vessel speed threshold after becoming equal to or less than the first vessel speed threshold. In other words, control hysteresis may not be set in the control for changing the predetermined period for averaging by the control unit.

[0095] In the above embodiment, an example was shown in which the control unit 14 is configured to reduce the predetermined period P for averaging processing so that the change in the vessel speed V becomes larger when the vessel speed V becomes equal to or lower than the vessel speed threshold value VP in the wave vessel speed control mode, but the present invention is not limited to this. In the present invention, the control unit may be configured not to reduce the predetermined period for averaging processing even when the vessel speed becomes equal to or lower than the vessel speed threshold value in the wave vessel speed control mode.

[0096] In the above embodiment, an example was shown in which the control unit 14 is configured to perform wave-induced vessel speed control such that the change in vessel speed V becomes large when the vessel speed V becomes equal to or lower than a predetermined vessel speed threshold VP that is a predetermined amount higher than the minimum vessel speed V0 in the wave-induced vessel speed control mode, but the present invention is not limited to this. In the present invention, the control unit may be configured not to perform wave-induced vessel speed control such that the change in vessel speed becomes large even when the vessel speed becomes equal to or lower than a predetermined vessel speed threshold VP that is a predetermined amount higher than the minimum vessel speed in the wave-induced vessel speed control mode.

[0097] In the above embodiment, an example has been shown in which the control unit 14 is configured to perform notification control to notify the vessel operator that the vessel speed V has reached the minimum vessel speed V0 when the vessel speed V reaches the minimum vessel speed V0 in the wavey vessel speed control mode, but the present invention is not limited to this. In the present invention, the control unit may be configured not to perform notification control to notify the vessel operator that the vessel speed has reached the minimum vessel speed even when the vessel speed reaches the minimum vessel speed in the wavey vessel speed control mode.

[0098] In the above embodiment, an example was shown in which the control unit 14 is configured to control the vessel speed in rough waves in the vessel speed control mode so that the vessel speed V becomes equal to or greater than a minimum vessel speed V0 set to be equal to or greater than the minimum speed at which the hull 10 can plan, but the present invention is not limited to this. In the present invention, the control unit may be configured to control the vessel speed in rough waves in the vessel speed control mode so that the vessel speed becomes equal to or greater than a minimum vessel speed set to be smaller than the minimum speed at which the hull can plan.

[0099] In the above embodiment, an example has been shown in which the operation unit 13 includes a remote controller and a steering wheel, but the present invention is not limited to this. In the present invention, the operation unit may include a joystick. In that case, the operation unit may include a joystick without including a remote controller and a steering wheel, or may include a joystick in addition to a remote controller and a steering wheel.

[0100] In the above embodiment, an example has been shown in which only one propulsion unit 20 is attached to the stern 11 of the hull 10, but the present invention is not limited to this. In the present invention, two or more propulsion units may be attached to the stern of the hull.

[0101] In the above embodiment, the propulsion unit 20 is an outboard motor attached to the stern 11 of the hull 10, but the present invention is not limited to this. In the present invention, the propulsion unit may be an inboard motor disposed inside the hull, or an inboard / outboard motor attached to the hull such that a portion of the propulsion unit is disposed inside the hull. [Explanation of symbols]

[0102] 10. Hull 13 Control section 14 Control section 20 Propulsion machine 100 Marine Propulsion Systems 110 Ships Ia Information on the vertical movement of the vessel Ian Latest information on the vessel's vertical movement K weighting factor K1 First weighting value K2 Second weighting value M Rate of change of target ship speed MM Maximum rate of change of target ship speed MM1 First rate of change maximum value MM2 Second rate of change maximum value N is the parameter to be averaged N1 First population value N2 Second population value P is the period for which averaging is performed P1 1st Period P2 2nd Period V Ship speed V0 Minimum ship speed VP Ship Speed ​​Threshold VP1 First ship speed threshold VP2 Second ship speed threshold

Claims

1. A propulsion unit provided in the hull; a control unit configured to control the drive of the propulsion unit to adjust the boat speed, and performing boat speed control in rough waves to adjust the boat speed based on information related to the up and down movement of the hull during rough waves, The control unit of the ship propulsion system is configured to perform the ship speed control in rough waves in a ship speed control mode in which the ship speed control in rough waves is performed so that the ship speed becomes equal to or greater than a predetermined minimum ship speed that is set in advance.

2. The control unit is configured to perform the wave-induced vessel speed control in the wave-induced vessel speed control mode so that the vessel speed becomes equal to or higher than the minimum vessel speed, which is set to be equal to or higher than the minimum speed at which the hull can plank.

3. The ship propulsion system according to claim 1, wherein the control unit is configured to perform notification control to notify an operator that the ship speed has reached the minimum ship speed when the ship speed becomes the minimum ship speed in the wave-induced ship speed control mode.

4. The ship propulsion system according to claim 1, wherein the control unit is configured to perform the ship speed control in rough waves so that the change in the ship speed becomes larger when the ship speed falls below a predetermined ship speed threshold value that is a predetermined amount higher than the minimum ship speed in the wavey ship speed control mode.

5. The control unit is The ship speed control in rough waves is performed based on a value obtained by averaging information about the vertical movement of the ship hull for a predetermined period of time, The ship propulsion system according to claim 4, wherein in the wave-induced ship speed control mode, when the ship speed becomes equal to or lower than the ship speed threshold, the predetermined period for the averaging process is shortened so that the change in the ship speed becomes larger.

6. 6. The ship propulsion system according to claim 5, wherein the control unit is configured, in the wavey ship speed control mode, to set the predetermined period for which the averaging process is performed to a first period so that the change in the ship speed becomes large when the ship speed becomes equal to or less than a predetermined first ship speed threshold, and to set the predetermined period for which the averaging process is performed to a second period longer than the first period when the ship speed becomes equal to or less than the first ship speed threshold and then equal to or greater than a predetermined second ship speed threshold that is greater than the first ship speed threshold.

7. The control unit is The ship speed control in rough waves is performed based on a value obtained by averaging information about the vertical movement of the ship hull for a predetermined period of time, The ship propulsion system of claim 4, wherein in the wave-condition ship speed control mode, when the ship speed becomes equal to or lower than the ship speed threshold, a weighting coefficient for adjusting the weighting of the information relating to the vertical movement of the hull is changed so that the change in the ship speed becomes larger when the ship speed becomes equal to or lower than the ship speed threshold, and so that the weighting of the most recent value of the information relating to the vertical movement of the hull is increased compared to the weighting of values ​​other than the most recent value of the information relating to the vertical movement of the hull.

8. 8. The ship propulsion system according to claim 7, wherein the control unit is configured, in the wave-in-ship ship speed control mode, when the ship speed becomes equal to or less than a predetermined first ship speed threshold, to set the weighting coefficient to a first weighting value so that the change in the ship speed is large and the weighting of the most recent value of the information relating to the vertical movement of the hull is greater than the weighting of the information relating to the vertical movement of the hull other than the most recent value, and to change the weighting coefficient to a second weighting value so that, when the ship speed becomes equal to or less than the first ship speed threshold and then equal to or more than a predetermined second ship speed threshold that is greater than the first ship speed threshold, the weighting of the most recent value of the information relating to the vertical movement of the hull is smaller than when the ship speed is equal to or less than the first ship speed threshold.

9. The control unit is The ship speed control in rough waves is performed based on a value obtained by averaging information about the vertical movement of the ship hull for a predetermined period of time, The vessel propulsion system according to claim 4, wherein in the rough vessel speed control mode, when the vessel speed falls below the vessel speed threshold, the parameter used for the averaging process is reduced so that the change in the vessel speed becomes larger.

10. 10. The vessel propulsion system according to claim 9, wherein the control unit is configured, in the rough vessel speed control mode, to set the parameter used in the averaging process to a first parameter value so that the change in the vessel speed becomes larger when the vessel speed becomes equal to or less than a predetermined first vessel speed threshold, and to set the parameter used in the averaging process to a second parameter value larger than the first parameter value when the vessel speed becomes equal to or less than the first vessel speed threshold and then equal to or greater than a predetermined second vessel speed threshold value that is larger than the first vessel speed threshold.

11. The ship propulsion system according to claim 4, wherein the control unit is configured to increase a maximum value of the rate of change of the ship speed so that the change in the ship speed becomes larger when the ship speed becomes equal to or lower than the ship speed threshold in the wavey ship speed control mode.

12. The ship propulsion system according to claim 11, wherein the control unit is configured, in the wavey ship speed control mode, to set the maximum value of the rate of change of the ship speed to a first change rate maximum value so that the change in the ship speed becomes large when the ship speed becomes equal to or less than a predetermined first ship speed threshold, and to set the maximum value of the rate of change of the ship speed to a second change rate maximum value smaller than the first change rate maximum value when the ship speed becomes equal to or less than the first ship speed threshold and then equal to or greater than a predetermined second ship speed threshold that is greater than the first ship speed threshold.

13. 2. The ship propulsion system according to claim 1, wherein the control unit is configured to perform the ship speed control in rough waves based on a moving average value obtained by averaging information regarding the up and down movement of the hull over a predetermined period of time.

14. An operation unit that receives an operation by the operator is further provided, The control unit is configured to perform the notification control when the boat speed becomes the minimum boat speed in the wavey boat speed control mode, and to change the minimum boat speed when the operator operates the operating unit to change the minimum boat speed.

15. The control unit is configured to perform the notification control when the boat speed becomes the minimum boat speed in the wavey boat speed control mode, and to increase the minimum boat speed when the operator operates the operating unit to increase the minimum boat speed.

16. 15. The vessel propulsion system according to claim 14, wherein the control unit is configured to restore the changed minimum vessel speed to an initial value when the power to the control unit is turned off or restarted.

17. A propulsion unit provided in the hull; a control unit configured to control the drive of the propulsion unit to adjust the boat speed, and performing boat speed control in rough waves to adjust the boat speed based on information related to the up and down movement of the hull during rough waves, The control unit is configured to perform the wave-induced vessel speed control in a wave-induced vessel speed control mode in which the wave-induced vessel speed control is performed so that the vessel speed becomes equal to or greater than a predetermined minimum vessel speed set in advance, in a vessel.

18. The control unit is configured to perform the wave-induced vessel speed control in the wave-induced vessel speed control mode so that the vessel speed becomes equal to or greater than the minimum vessel speed, which is set to be equal to or greater than the minimum speed at which the hull can plank.

19. The ship according to claim 17, wherein the control unit is configured to perform notification control to notify a ship operator that the ship speed has reached the minimum ship speed when the ship speed becomes the minimum ship speed in the wavey ship speed control mode.

20. The ship described in claim 17, wherein the control unit is configured to perform the wave-induced ship speed control in the wave-induced ship speed control mode so that when the ship speed falls below a predetermined ship speed threshold value that is a predetermined amount higher than the minimum ship speed, the change in the ship speed becomes larger.

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