JP7684833B2 - Ship Navigation Systems - Google Patents

Description

The present invention relates to a ship navigation system.

Conventionally, ships propel the hull by rotating a screw using a driving unit such as an internal combustion engine or an electric motor, and the direction of the hull's movement is changed by adjusting the direction of the rudder or screw installed at the stern.
For example, the following Patent Document 1 discloses a ship propulsion system and a ship that use both a propeller powered by an internal combustion engine and a propeller powered by an electric motor. The ship propulsion system includes a first power transmission device that transmits the power of the internal combustion engine to a screw, a second power transmission device that transmits the power of the electric motor to the screw and is attached to the hull so as to be vertically rotatable independently of the first power transmission device, an actuator for vertically rotating the second power transmission device, and a control device. The control device is configured to be able to select between a first drive mode in which the internal combustion engine is driven but the electric motor is not driven, and a second drive mode in which the internal combustion engine is not driven but the electric motor is driven, and when the first drive mode is selected, the control device operates the actuator to rotate the second power transmission device upward.

JP 2019-199148 A

If the orientation of the rudder member or screw cannot be adjusted for some reason, i.e., if the rudder mechanism breaks down, the direction of travel of the hull cannot be controlled, causing problems in the navigation of the ship. Therefore, it is desirable to provide a structure for when the rudder mechanism of the ship breaks down.
The present invention has been made in consideration of the above circumstances, and has an object to provide a ship navigation system for improving the safety of ship navigation.

In order to achieve the above-mentioned object, one embodiment of the present invention is a ship navigation system comprising a first screw propeller provided on the left side of the hull, a first drive unit that rotates the first screw propeller, a second screw propeller provided on the right side of the hull, a second drive unit that rotates the second screw propeller, and a steering mechanism that adjusts the direction of movement of the hull, characterized in that the system also comprises a failure detection unit that detects a failure of the steering mechanism, and a movement control unit that, when a failure of the steering mechanism is detected, adjusts the output of the first drive unit and the second drive unit, respectively, so that the hull moves in a desired direction, and adjusts the rotational direction of the first screw propeller and the second screw propeller, respectively.
One embodiment of the present invention is characterized in that the movement control unit determines the normal outputs of the first drive unit and the second drive unit so that the hull moves straight, and when turning the hull to the left or right, increases or decreases the output of either the first drive unit or the second drive unit from the normal output.
One embodiment of the present invention is characterized in that, when turning the hull to the left or right, the movement control unit increases or decreases the output of the drive unit on the side having a smaller output under normal conditions.
One embodiment of the present invention is characterized in that the movement control unit sets the normal output to 50% or less of the maximum output of the drive unit.
One embodiment of the present invention is characterized in that the invention further includes an obstacle detection unit that detects an obstacle located ahead of the hull in the direction of travel, and when the obstacle is detected ahead of the hull in the direction of travel, the movement control unit rotates the first screw propeller and the second screw propeller in the opposite direction to when moving forward, and moves the hull to bypass the obstacle after the distance between the hull and the obstacle becomes greater than or equal to a predetermined distance.
One embodiment of the present invention is characterized in that the steering mechanism adjusts the direction of movement of the hull by swinging the orientation of the first screw propeller and the second screw propeller relative to the hull, and when a failure is detected that prevents either the first screw propeller or the second screw propeller from moving, the movement control unit stops the drive unit that rotates the screw propeller on the failed side, and moves the hull using only the screw propeller and drive unit on the healthy side.
One embodiment of the present invention is characterized in that the ship further comprises a plurality of actuators that respectively operate a plurality of operating members for navigating the ship operated by a pilot, a ship-side communication unit that receives remote operation command information, and an operating member control unit that operates each of the plurality of actuators based on the remote operation command information received by the ship-side communication unit, wherein the plurality of actuators are provided in locations that do not interfere with manual operation of the operating members by the pilot seated in the pilot's seat, and the operating member control unit is configured to be selectable between a remote operation mode in which the plurality of actuators are respectively controlled based on the remote operation command information to operate each of the plurality of operating members, and a manual operation mode that enables manual operation of each of the plurality of operating members by the pilot.

According to one embodiment of the present invention, if the ship's steering mechanism fails, the ship's direction of travel is adjusted by changing the output of the left and right drive units and the rotation direction of the screw propellers, so the ship can be turned even when the steering mechanism fails, which is advantageous in improving the safety of the ship.
According to one embodiment of the present invention, the output (normal output) of the left and right drive units is determined so that the hull moves straight, and when turning the hull to the left or right, the output of the left and right drive units is increased or decreased from the normal output, so that the direction of the hull's travel can be adjusted regardless of the steering situation when the rudder mechanism fails.
According to one embodiment of the present invention, when turning the hull to the left or right, the output of the drive unit on the side with the smaller normal output is increased or decreased, which is advantageous in reducing the energy consumption of the drive units compared to increasing or decreasing the output of the drive unit on the side with the larger normal output.
According to one embodiment of the present invention, the normal output is set to 50% or less of the maximum output of the drive unit, which is advantageous in steadily reducing the energy consumption of the drive unit.
According to one embodiment of the present invention, when an obstacle is detected ahead of the hull in the direction of travel, the left and right screw propellers are rotated in the opposite direction to when moving forward, and the hull is moved to go around the obstacle after the distance between the hull and the obstacle becomes equal to or greater than a predetermined distance, which is advantageous in reliably avoiding contact between the obstacle and the hull.
According to one embodiment of the present invention, in a ship that is steered by swinging the direction of the left and right screw propellers relative to the hull, if a failure of the steering mechanism is detected (the screw propellers cannot move), the drive unit that rotates the screw propeller on the failed side is stopped, and the hull is moved using only the screw propeller and drive unit on the healthy side, which is advantageous in adjusting the direction of the hull's travel while reducing energy consumption in the drive unit.
According to one embodiment of the present invention, a plurality of actuators for respectively operating a plurality of operating members for navigating the ship are provided at locations that do not interfere with the manual operation of the plurality of operating members by the ship operator seated in the steering seat, and by selecting a remote operation mode of the operating member control unit, the plurality of actuators are controlled based on remote operation command information to operate the plurality of operating members, thereby enabling the ship to be remotely operated, and by selecting a manual operation mode of the operating member control unit, the plurality of operating members can be manually operated. Therefore, there is no need to modify the ship to perform remote operation, and the ship can be remotely operated, and the ship can be manually operated while sitting in the steering seat without returning the ship to its original state, which is advantageous in improving usability.

1 is a plan view illustrating a schematic configuration of a ship to which a ship navigation system according to an embodiment is applied. FIG. 2 is a block diagram showing a propulsion mechanism of a vessel. FIG. 2 is a block diagram showing the configuration of a control system of the ship. FIG. 2 is a block diagram showing a configuration of a remote control device. 1A is an explanatory diagram of a first actuator that operates the ignition switch of a ship, (A) is a side view showing the state in which the ignition switch and the first actuator are disengaged, (B) is an arrow view taken along line B-B of (A), (C) is a side view showing the state in which the ignition switch and the first actuator are engaged, and (D) is an arrow view taken along line D-D of (C). 5A and 5B are explanatory diagrams of a second actuator that operates the steering wheel of a boat, in which (A) is a front view of the steering wheel, and (B) is a view taken along line XX of (A). FIG. 13 is an explanatory diagram of a third actuator that operates the throttle lever of the boat, and is a side view of the throttle lever as viewed from the width direction of the hull of the small boat. (A) is a figure showing the state in which image information showing the surroundings of the ship is displayed on the display unit, and (B) is a figure showing the state in which an icon showing the position of the ship is displayed superimposed on map information on the display unit. FIG. 4 is a diagram showing a schematic diagram of the outputs of the left and right engines when a steering mechanism fails. FIG. 4 is a diagram showing a schematic diagram of the outputs of the left and right engines when a steering mechanism fails. FIG. 4 is a diagram showing a schematic diagram of the outputs of the left and right engines when a steering mechanism fails. FIG. 4 is a diagram showing a schematic diagram of the outputs of the left and right engines when a steering mechanism fails. FIG. 11 is a plan view illustrating another configuration of the ship.

<System Configuration>
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A ship navigation system according to an embodiment of the present invention will now be described in detail with reference to the drawings.
In the embodiment, a case will be described in which the ship is an unmanned ship 10 that is remotely operated. The ship 10 may be, for example, a small ship such as a fishing boat, a tourist boat, a cruiser, or the like, and the type, gross tonnage, and purpose of the ship are arbitrary.

As shown in Figures 1 to 3, the ship 10 includes a hull 12, engines 13 (13A, 13B), screw propellers 14 (14A, 14B), rudder 15 (15A, 15B), steering actuators 16 (16A, 16B), a ship steering control device 18, an ignition switch 20, a handlebar 22, a throttle lever 24, which constitute a plurality of operating members, a first actuator 26, a second actuator 28, and a third actuator 30, which constitute a plurality of actuators, a ship-side control device 32, four cameras, a front camera 68A, a rear camera 68B, a left camera 68C, and a right camera 68D, and a positioning unit 70.

As shown in FIG. 1, the hull 12 is equipped with an operating console 1202 provided near the front of the hull 12, a pilot's seat 1204 located behind the operating console 1202 and in which the pilot sits, and a transom (stern plate) 1206 that separates the stern of the hull 12 and extends in the width direction of the hull.

The engine 13 and the screw propeller 14 function as a propulsion mechanism for propelling the hull 12 .
In this embodiment, the engine 13 and the screw propeller 14 are provided on each of the left and right sides of the hull 12. That is, the ship 10 is provided with a left screw propeller 14A, which is a first screw propeller provided on the left side of the hull 12, a left engine 13A, which is a first engine that rotates the left screw propeller 14A, a right screw propeller 14B, which is a second screw propeller provided on the right side of the hull 12, and a right engine 13B, which is a second engine that rotates the right screw propeller 14B. In this embodiment, the screw propeller 14 is rotated by the engine 13 (internal combustion engine), but may be rotated by, for example, a motor (electric motor). A drive source that rotates the screw propeller 14, such as the engine 13 or a motor, is called a drive unit.

The engine 13 is a drive source (drive unit) that rotates the screw propeller 14 and generates a propulsive force that propels the hull 12 .
As shown in FIG. 2, the engine 13 includes a throttle valve 1304A, a throttle actuator 1304B, and an ECU (Engine Control Unit) 1304C.
The throttle valve 1304 A adjusts the amount of air drawn into the engine 13 .
The throttle actuator 1304B adjusts the opening of the throttle valve 1304A.
The ECU 1304C controls a throttle actuator 1304B and a shift actuator 1306B of the power transmission mechanism 130, which will be described later, based on a tilt angle signal of the throttle lever 24 provided from the ship steering control device 18, which will be described later.

The power transmission mechanism 130 (130A, 130B) is provided corresponding to the left and right engines 13A, 13B, and includes a drive shaft 1302 that inputs the driving force of the engine 13, a shift mechanism 1306A that switches and transmits the driving force transmitted to the drive shaft 1302 to a screw propeller shaft 1410 (see Figure 1), the screw propeller shaft 1410 that transmits the driving force transmitted from the shift mechanism 1306A to the screw propeller 14 that generates propulsion for the hull 12 by rotating underwater, and a shift actuator 1306B that operates the shift mechanism 1306A.
The shift mechanism 1306A is switched by a shift actuator 1306B between a forward drive position in which the screw propeller shaft 1410 rotates forward, a reverse drive position in which the screw propeller shaft 1410 rotates backward, and a neutral position in which the rotation of the screw propeller shaft 1410 is stopped.
When the shift mechanism 1306A is switched to the forward position, the screw propeller shaft 1410 is rotated in the forward direction, whereby the screw propeller 14 generates a propulsive force that moves the hull 12 forward.
When the shift mechanism 1306A is switched to the reverse position, the screw propeller shaft 1410 is rotated in the reverse direction, and the screw propeller 14 generates a propulsive force that moves the hull 12 backward.
When the shift mechanism 1306A is switched to the neutral position, the rotation of the screw propeller shaft 1410 is stopped, and the generation of propulsive force by the screw propeller 14 is stopped.

The rudder 15 and the steering actuator 16 function as a steering mechanism that adjusts the direction of movement of the hull 12 .
The rudder 15 is a plate-like member arranged on the hull rear side of the screw propeller 14. In this embodiment, the rudder 15 includes a left rudder 15A, which is a left rudder arranged adjacent to the hull rear side of the left screw propeller 14A arranged on the left side of the hull 12, and a right rudder 15B arranged adjacent to the hull rear side of the right screw propeller 14B arranged on the right side of the hull 12. The rudder 15 has a streamlined cross-sectional shape and extends a predetermined length in the vertical direction of the hull 12. The rudder 15 is attached to an arm 1502 extending from the hull 12 so as to be swingable about a steering axis Z extending in the vertical direction of the hull 12.

The steering actuator 16 changes the steering angle of the rudder 15 (the angle that the rudder surface direction XL of the rudder 15 makes with respect to the fore-aft direction of the hull 12) by swinging the rudder 15 around the steering axis Z based on the operation angle signal of the handle 22 provided by the ship steering control device 18 described later. In this embodiment, a left steering actuator 16A, which is a first steering actuator that swings the left rudder 15A, and a right steering actuator 16B, which is a second steering actuator that swings the right rudder 15B, are provided.

In this embodiment, two rudders 15A and 15B are provided to correspond to the two screw propellers 14A and 14B, but it is also possible to provide only one rudder 15, for example, at the center of the transom 1206.

As shown in Figures 1 and 2, the ship steering control device 18 controls the engine 13 and rudder 15 in response to the operation of multiple operating members 20, 22, and 24. Specifically, it starts and stops the engine 13, adjusts the rotation speed, and adjusts the steering angle of the rudder 15.

The multiple operating members 20, 22, 24 shown in Figs. 1 and 3 are members that are operated by a pilot to navigate (steer) the ship.
In this embodiment, three operating members, an ignition switch 20, a handle 22, and a throttle lever 24, are arranged side by side on the operation console 1202 at intervals in the width direction of the hull.
The ignition switch 20 is used to start and stop the engine 13 .
As shown in FIGS. 5(A) to (D), the ignition switch 20 has a key cylinder 2002 and an ignition key 2004.
The ignition switch 20 provides an off signal, an on signal, and a start signal to the ship maneuvering control device 18 when the ignition key 2004 inserted in the key cylinder 2002 is turned to the off position, the on position, and the start position, respectively. This causes the ship maneuvering control device 18 to stop or supply power from a battery (not shown) to the engine 13, and also to start the engine 13.

As shown in FIGS. 6A and 6B, the handle 22 is rotated to steer the boat 10.
The handle 22 includes a handle body 2202 having a circular cross section and extending in an annular shape, a handle shaft 2204 of the handle body 2202 , and spokes 2206 connecting the handle shaft 2204 and the handle body 2202 .
In this embodiment, the handle shaft 2204 extends substantially along the fore-and-aft direction of the hull 12 .
An operation angle signal indicating the operation angle of the handle 22 detected by an operation angle sensor (not shown) is supplied to the ship steering control device 18, and in response to this, the ship steering control device 18 drives the steering actuator 16 to adjust the steering angle.

As shown in FIG. 7, the throttle lever 24 is used to adjust the output of the engine 13 .
The throttle lever 24 includes a swing shaft 2404 that is swingably mounted on the operation console 1202 in the fore-and-aft direction of the hull 12, and a gripped portion 2406 that is provided at the tip of the swing shaft 2404 and that can be gripped by hand.
The throttle lever 24 detects a tilt angle signal indicating the tilt angle of the throttle lever 24 by a lever position sensor (not shown) and supplies the signal to the ECU 1304C of the engine 13 via the maneuvering control device 18. The ECU 1304C then drives the throttle actuator 1304B and the shift actuator 1306B to control the engine 13.
That is, the throttle lever 24 is tiltable within a neutral range, a forward range which is a range forward of the hull 12 from the neutral range, and a reverse range which is a range rearward of the hull 12 from the neutral range.

When the throttle lever 24 is positioned in the neutral range, the ECU 1304C switches the power transmission mechanism 130 to the neutral position using the shift actuator 1306B and closes the throttle valve 1304A using the throttle actuator 1304B, thereby stopping the engine 13 and the boat 10.
When the throttle lever 24 is positioned in the forward range, the ECU 1304C switches the power transmission mechanism 130 to the forward position using the shift actuator 1306B, and adjusts the opening of the throttle valve 1304A using the throttle actuator 1304B to a larger degree as the forward tilt angle of the throttle lever 24 increases, thereby increasing the rotation speed of the engine 13, moving the boat 10 forward and adjusting the sailing speed.
When the throttle lever 24 is positioned in the reverse range, the ECU 1304C switches the power transmission mechanism 130 to the reverse position using the shift actuator 1306B, and adjusts the opening of the throttle valve 1304A using the throttle actuator 1304B to a larger degree as the rearward tilt angle of the throttle lever 24 increases, thereby increasing the rotation speed of the engine 13, reversing the boat 10 and adjusting the sailing speed.

A plurality of actuators 26, 28, 30 shown in FIGS. 1 and 3 operate a plurality of operating members 20, 22, 24.
In this embodiment, three actuators are provided as multiple actuators: a first actuator 26 that operates the ignition switch 20, a second actuator 28 that operates the handle 22, and a third actuator 30 that operates the throttle lever 24.

As shown in FIGS. 5A to 5D, the first actuator 26 includes a motor 33 and a rotating member 34 .
The motor 33 and the rotating member 34 are provided at a location (operation console 1202 ) that does not interfere with the manual operation of the ignition switch 20 (ignition key 2004 ) by the pilot seated at the pilot's seat 1204 .
The motor 33 is detachably mounted on the operation console 1202 via a bracket (not shown).
The rotating member 34 is connected to a drive shaft 3302 of the motor 33 .
The rotating member 34 is provided with an engagement recess 3402 that can be engaged with and disengaged from a head 2004 A of an ignition key 2004 inserted into a key cylinder 2002 of the ignition switch 20 .
That is, the rotating member 34 is detachably connected to the ignition key 2004 and rotatably connected thereto, and can be rotated.

As shown in Figures 5 (A) and (B), the rotating member 34 is positioned so that the engagement recess 3402 faces the head 2004A of the ignition key 2004, and then, as shown in Figures 5 (C) and (D), the rotating member 34 and the motor 33 are moved toward the ignition key 2004, so that the head 2004A is inserted into and engaged with the engagement recess 3402, and in this state the first actuator 26 is attached to the operation console 1202 via a bracket not shown.
With the engagement recess 3402 engaged with the head 2004A, a drive signal is supplied to the motor 33 from the ship-side control device 32 described later, thereby driving the motor 33 and rotating the ignition key 2004 to each of the off position, on position, and start position.
This causes the ship steering control device 18 to stop or supply power from the battery to the engine 13 , and also to start the engine 13 .
In addition, when the engagement recess 3402 is engaged with the head 2004A, the drive signal supplied to the motor 33 by the ship-side control device 32 is turned off, thereby making the motor 33 servo-free, and the pilot seated in the pilot's seat 1204 can manually operate the ignition key 2004 via the rotating member 34 by grasping the rotating member 34.
When removing the ignition key 2004 from the key cylinder 2002, the motor 33 is removed from the operation console 1202, and the engaging recess 3402 is moved away from the head 2004A.

As shown in FIGS. 6A and 6B, the second actuator 28 includes a motor 39 and a drive roller 40 .
The motor 39 and the drive roller 40 are detachably mounted via a bracket (not shown) at a location (operation console 1202) that does not interfere with manual operation of the handle 22 by an operator seated at the pilot's seat 1204.
The motor 39 is attached to the operation console 1202 and is disposed so that its drive shaft 3902 is substantially perpendicular to the handle shaft 2204 of the handle 22 .
The drive roller 40 is attached to the tip of the drive shaft 3902 .
The drive roller 40 is disposed diagonally downward and forward of the hull 12 at a portion of the circumferential direction of the handle body 2202, and engages with the handle body 2202, enabling the handle body 2202 to rotate as the drive roller 40 is rotated.
The drive roller 40 has a groove 4002 that engages with the surface of the handle body 2202 facing diagonally downward in front of the hull 12, and is designed so that the rotational driving force of the motor 39 is efficiently transmitted to the handle body 2202 via the groove 4002 of the drive roller 40.

The motor 39 rotates the handle 22 forward and backward via the drive shaft 3902 and the drive roller 40 when a drive signal is supplied from the ship-side control device 32 .
Therefore, as the motor 39 rotates in the forward and reverse directions, the drive roller 40 rotates the handle body 2202 in the forward and reverse directions, and the steering angle signal generated by the steering angle sensor is supplied to the steering control device 18, which drives the steering actuator 16 and adjusts the steering angle.
In addition, when the drive signal supplied to the motor 39 by the ship-side control device 32 is turned off, the motor 39 becomes servo-free, and the pilot seated in the pilot's seat 1204 can manually operate the handle 22.

As shown in FIG. 7, the third actuator 30 is composed of a direct-acting cylinder (direct-acting electric cylinder) 30A, and includes a cylinder body 3002, a motor (not shown) incorporated in the cylinder body 3002, and a piston rod 3004 incorporated in the cylinder body 3002.
The linear cylinder 30A is detachably mounted via a bracket (not shown) at a location (operation console 1202) that does not interfere with manual operation of the throttle lever 24 by an operator seated at the pilot's seat 1204.
The cylinder body 3002 is arranged so that the direction in which the piston rod 3004 projects and retracts coincides with the fore-and-aft direction of the hull 12 .
The tip of the piston rod 3004 is connected to the middle part in the longitudinal direction of the swing shaft 2404 of the throttle lever 24 via a spherical bearing (not shown) of the connecting part 42.
Therefore, when a drive signal is supplied to the motor by the ship-side control device 32, the piston rod 3004 extends and retracts relative to the cylinder body 3002, and the throttle lever 24 is tilted over the forward, neutral, and reverse ranges, thereby adjusting the output of the engine 13 and adjusting the forward, stopped, reverse, and sailing speed of the ship 10.
In addition, when the drive signal supplied to the motor is turned off by the ship-side control device 32, the motor becomes servo-free, and the pilot seated in the pilot's seat 1204 can manually operate the throttle lever 24.

As shown in FIG. 3, the front camera 68A captures an image of the area in front of the hull 12 and generates image information.
The rear camera 68B captures images of the rear of the hull 12 and generates image information.
The left camera 68C captures images of the left side of the hull 12 and generates image information.
The right camera 68D captures images of the right side of the hull 12 and generates image information.
These four pieces of image information are transmitted from the vessel side communication unit 60 to the remote control side communication unit 58 of the remote control device 44 (see FIG. 4) via a wireless line.
The image information may be a moving image or a still image generated at regular time intervals.

The positioning unit 70 determines the position of the small vessel based on a positioning signal received from a positioning satellite, and generates positioning information.
Such positioning satellites are used in Global Navigation Satellite Systems (GNSSs), such as GPS, GLONASS, Galileo, and Quasi-Zenith Satellite System (QZSS), and one of the positioning satellites used in these positioning systems may be used, or two or more positioning satellites may be used in combination.
The positioning information generated by the positioning unit 70 is transmitted from the vessel side communication unit 60 to the remote control side communication unit 58 of the remote control device 44 (see FIG. 4) via a wireless line.

In the present embodiment, the case where both the multiple cameras 68A to 68D and the positioning unit 70 are provided has been described, but only one of them may be provided. However, in the case of the present embodiment, it is possible to grasp both the conditions around the vessel 10 and the current position of the vessel 10, which is more advantageous in terms of accurate remote operation of the vessel 10.
In the present embodiment, the case where four cameras, namely, the front camera 68A, the rear camera 68B, the left camera 68C, and the right camera 68D, are provided has been described, but the number and arrangement of the cameras are arbitrary. Also, instead of providing a plurality of cameras, it is arbitrary to use a spherical camera or a semi-spherical camera with a wide imaging range.

As shown in FIG. 1, the ship-side control device 32 is mounted on the hull 12 and controls the first, second, and third actuators 26, 28, and 30 based on remote operation command information transmitted from the remote operation device 44 (see FIG. 4). The ship-side control device 32 will be described in detail later.

Next, the remote control device 44 will be described in detail with reference to FIG.
The remote control device 44 is operated by an operator located at a location away from the ship 10, and transmits remote operation command information generated by the operator's operation to the ship-side control device 32 via a wireless line. In this embodiment, it is possible to perform remote operation even in a range where the ship 10 cannot be seen by the operator performing remote operation. That is, in this embodiment, image information of the surroundings of the ship 10 and positioning information of the ship 10 are acquired, and based on the image information and positioning information, the remote control device 44 displays the image information and also displays the positioning information of the ship 10 on a map.

The remote control device 44 includes first to third remote control levers 46, 48, 50, angle sensors 52A, 52B, 52C, a mode change switch 54, an operation unit 72, a map database 74, a display unit 76, a remote control unit 56, and a remote control communication unit 58.

The first to third remote control levers 46, 48, and 50 are composed of remote control operating members (joysticks) that are swung to remotely control the ignition switch 20 (ignition key 2004), the handle 22, and the throttle lever 24.

Angle sensors 52A, 52B, and 52C are provided corresponding to each remote control lever 46, 48, and 50, and output detection signals indicating the angles corresponding to the operating positions of each remote control lever 46, 48, and 50.

The mode changeover switch 54 is operated to switch between a remote operation mode (described later) and a manual operation mode.

The operation unit 72, in response to an operation by the operator, instructs the notification unit 56B, described later, to switch the information to be displayed on the display unit 76. The operation unit 72 is composed of, for example, a touch panel provided on the display surface of the display unit 76 or a key switch provided independently of the display unit 76.
The map database 74 stores map information including the location where the vessel 10 is sailing, and the map information is associated with positioning information (location information) on the earth.
The display unit 76 displays image information of the periphery of the vessel 10 under the control of a notification unit 56B, which will be described later, and also displays the current position of the vessel 10 on map information.

The remote control unit 56 is made up of a CPU, a ROM for storing and storing control programs, a RAM for operating the control programs, an EEPROM for storing various data in a rewritable manner, the angle sensors 52A, 52B, and 52C, a mode change switch 54, and an interface unit for interfacing with peripheral circuits, etc.

The remote control unit 56 executes the above control program to function as a command information generating unit 56A, a notification unit 56B, and a failure control unit 56C.
The command information generating section 56A generates remote control command information based on the detection signals supplied from the angle sensors 52A, 52B, and 52C.
The command information generating section 56A generates mode switching command information based on an operation signal supplied from the mode switching switch 54.

The notification unit 56B displays image information transmitted from the ship-side communication unit 60 via a wireless line on the display unit 76, and also reads map information from the map database 74 based on the positioning information transmitted from the ship-side communication unit 60 via a wireless line, and superimposes an icon indicating the current position of the ship 10 onto the map information based on the positioning information and displays it on the display unit 76.
The notification unit 56B also switches between image information and map information and displays it on the display unit 76 in response to operation of the operation unit 72. Alternatively, the notification unit 56B selectively displays image information of the front, rear, left, and right sides of the hull 12 on the display unit 76.
For example, Figure 8 (A) shows a state in which image information of the front of the hull 12 captured by the forward camera 68A is displayed on the display screen 7602 of the display unit 76, and in this example, the horizon 2 and land 4 are displayed.
FIG. 8(B) shows a state in which an icon 8 indicating the current position of the ship 10 is superimposed on map information showing the land 4 and the sea 6 on the display screen 7602 of the display unit 76 .

The failure time control unit 56C generates remote operation command information instead of the command information generating unit 56A when a failure occurs in the vessel 10. The failure time control unit 56C may be one function of the command information generating unit 56A.
In this embodiment, the failure control unit 56C generates remote operation command information instead of the command information generation unit 56A when the steering mechanism of the ship 10 (at least one of the rudder 15 or the steering actuator 16, or their surrounding parts) fails.
The failure control unit 56C will be described in detail later.

The remote control communication unit 58 is configured to be able to communicate with the ship communication unit 60 via a wireless line, and transmits the remote control command information and mode switching command information generated by the command information generation unit 56A to the ship communication unit 60 via a wireless line.

Next, the ship-side control device 32 will be described in detail.
As shown in FIG. 3, the vessel-side control device 32 includes a vessel-side communication unit 60 , first to third detection units 62 A to 62 C, a servo control unit 64 , and a control unit 66 .
The ship side communication unit 60 receives remote operation command information transmitted from the remote operation side communication unit 58 via a wireless line.
The first to third detection units 62A to 62C detect the amount of operation of the ignition switch 20 (ignition key 2004), the handle 22, and the throttle lever 24 by the first to third actuators 26, 28, and 30.
More specifically, the first detector 62A detects the amount of rotation (angle) of the drive shaft 2602 of the first actuator (motor) 26 as the amount of operation.
The second detector 62B detects the amount of rotation (angle) of the drive shaft 2802 of the second actuator (motor) 28 as the amount of operation.
The third detection unit 62C detects the amount of movement of the piston rod 3004 of the third actuator (linear electric cylinder) 30 as the amount of operation.
The servo control unit 64 performs servo control of the first actuator 26 (motor 33), the second actuator 28 (motor 39), and the third actuator 30 (linear cylinder 30A) based on the operation amounts detected by the first to third detection units 62A, 62B, and 62C, respectively, under the control of the operating member control unit 66A.

The control unit 66 is composed of a CPU, a ROM for storing and remembering control programs, a RAM as an operating area for the control programs, an EEPROM for storing various data in a rewritable manner, the first to third detection units 62A to 62C, the servo control unit 64, an interface unit for interfacing with peripheral circuits, etc.
The control unit 66 functions as an operation member control unit 66A by executing the above control program.
The operating member control unit 66A monitors the detection results of the first to third detection units 62A to 62C based on remote operation command information received via the ship-side communication unit 60, and controls the servo control unit 64 to drive and control the first to third actuators 26, 28, and 30 to move the ignition switch 20 (ignition key 2004), the handle 22, and the throttle lever 24.
In addition, the operating member control unit 66A is configured to be able to select between a remote operation mode and a manual operation mode by operating the mode switching switch 54 of the remote operation device 44 and receiving mode switching command information generated by the remote operation side control unit 56 via the remote operation side communication unit 58 and the ship side communication unit 60.
When the operation member control unit 66A is set to the remote operation mode in response to the mode switching command information, it performs remote operation in response to an operation on the remote operation device 44.
That is, the operating member control section 66A controls the first to third actuators 26, 28, 30 based on remote operation command information to operate the ignition switch 20 (ignition key 2004), the handle 22, and the throttle lever 24.
Furthermore, when the operating member control unit 66A is set to the manual operation mode in response to the mode switching command information, it controls the servo control unit 64 to turn off the drive signals to the motor 33 of the first actuator 26, the motor 39 of the second actuator 28, and the motor of the third actuator, i.e., by disabling the servo control of the servo control 64, the first to third actuators 26, 28, 30 are servo-free and manual operation of the ignition switch 20 (ignition key 2004), the handle 22, and the throttle lever 24 is possible.
Alternatively, the mode changeover switch 54 may be provided on the vessel-side control device 32, and the operation member control unit 66A that receives operation of the mode changeover switch 54 may select between the remote operation mode and the manual operation mode.

<Normal control>
Next, a description will be given of the control in the ship navigation system of this embodiment under normal circumstances (when the steering mechanism is not malfunctioning).
First, a case where the operator remotely controls the boat 10 via the remote control device 44 will be described.
It is assumed that the head 2004A of the ignition key 2004 is engaged with the engagement recess 3402 of the rotating member 34, and the vessel-side control device 32 is set to the remote operation mode by the mode changeover switch 54 in advance.
The operator remotely controls the vessel 10 while monitoring the vessel 10. That is, the operator remotely controls the vessel 10 while grasping the situation around the vessel 10, specifically, the presence or absence of other vessels, the positional relationship between the vessel 10 and those vessels, the positional relationship between the vessel 10 and land, etc., based on the image information displayed on the display unit 76 (if the vessel 10 is in a position visible to the operator, the operator may directly view the vessel 10).
In addition, based on the map information displayed on the display unit 76, the current position of the ship 10 can be grasped and the ship 10 can be accurately remotely operated from a location away from the ship 10.

When the operator operates the first to third remote control levers 46, 48, 50 of the remote control device 44, the command information generating unit 56A generates remote operation command information based on detection signals detected by the angle sensors 52A, 52B, 52C. The remote operation command information is transmitted from the remote operation side communication unit 58 to the ship side communication unit 60 via a wireless line.
In the ship 10, remote operation command information received via the ship side communication unit 60 is supplied to the operating member control unit 66A, and the operating member control unit 66A monitors the detection results of the first to third detection units 62A to 62C based on the remote operation command information, and controls the servo control unit 64 to drive and control the first to third actuators 26, 28, 30 to operate the ignition switch 20 (ignition key 2004), the handle 22, and the throttle lever 24.
That is, the first actuator 26 operates the ignition switch 20 to switch the ignition switch 20 between an OFF position, an ON position, and a start position, thereby stopping and starting the engine 13.
In addition, the steering angle of the rudder 15 is adjusted by operating the handle 22 with the second actuator 28, and the boat 10 is steered.
Furthermore, the throttle lever 24 is operated by the third actuator 30 to adjust the propulsive force of the engine 13, switch the boat 10 between forward, reverse, and stop, and adjust the traveling speed.
Normally, in either the case of remote control or the case of manual control described below, the outputs of the left and right engines 13A, 13B are controlled to be equal.

Next, a case where the operator on board the boat 10 performs manual operation will be described.
It is assumed that the vessel-side control device 32 has been set in advance to the manual operation mode by the mode changeover switch 54.
The engine 13 is stopped and started by manually switching the ignition switch 20 between the OFF position, the ON position, and the START position by the pilot seated at the pilot's seat 1204 .
In addition, the pilot manually operates the handle 22 to adjust the steering angle of the rudder 15 and steer the boat 10.
In addition, the operator manually operates a throttle lever 24 to adjust the propulsive force of the engine 13, switch the boat 10 between forward, reverse, and stop, and adjust the boat speed.
At this time, since the first to third actuators 26, 28, 30 are servo-free, manual operation of the ignition switch 20 (ignition key 2004), the handle 22, and the throttle lever 24 is not impeded.

In this manner, in this embodiment, the first to third actuators 26, 28, 30 which operate the operating members for navigating (steering) the vessel 10 operated by the vessel operator are detachably provided at locations which do not interfere with the manual operation of the operating members by the vessel operator seated in the vessel operator's seat 1204, and by selecting the remote operation mode of the operating member control unit 66A, the first to third actuators 26, 28, 30 are controlled based on remote operation command information to operate the ignition switch 20 (ignition key 2004), the handle 22, and the throttle lever 24, thereby enabling the vessel 10 to be remotely operated, and by selecting the manual operation mode of the operating member control unit 66A, the first to third actuators 26, 28, 30 are made servo-free so that the ignition switch 20 (ignition key 2004), the handle 22, and the throttle lever 24 can be manually operated by the vessel operator seated in the vessel operator's seat 1204.
This allows the pilot to sit in the pilot's seat and pilot the vessel 10 without returning the vessel 10 to its original state, and also allows the pilot to remotely operate the vessel 10 without being on board, which is advantageous in improving the ease of use of the vessel 10.

<Control during failure>
Next, the control to be performed when the steering mechanism of the vessel 10 fails will be described.
As shown in FIG. 4, the failure control unit 56C includes a failure detection unit 560, an obstacle detection unit 562, and a movement control unit 564.
The fault detection unit 560 detects a fault in the rudder mechanism (at least one of the rudder 15 or the steering actuator 16, or the periphery thereof). The fault detection unit 560 estimates the traveling direction of the ship 10 corresponding to the amount of operation of the handle 22 based on the operation of the second remote control lever 48, for example, and determines that the rudder mechanism has failed when the deviation between the estimated traveling direction and the actual traveling direction of the ship 10 exceeds an allowable value, i.e., when the traveling direction of the ship 10 is not adjusted according to the pilot's operation. The traveling direction of the ship 10 is detected, for example, using positioning data from the positioning unit 70.
In addition, the fault detection unit 560 may monitor whether the steering actuator 16 and the rudder 15 are operating in accordance with the command information from the command information generation unit 56A, for example by detecting the current value of the steering actuator 16 or by providing a steering angle sensor in the rudder 15 to detect the steering angle, and may determine that the steering mechanism has failed if they are not operating in accordance with the command information.

The obstacle detection unit 562 detects obstacles located ahead in the traveling direction of the hull 12. The obstacle detection unit 562 analyzes images captured by the cameras 68A to 68D provided on the ship 10, for example, to detect obstacles located ahead in the traveling direction of the hull 12, such as objects such as buoys, driftwood, and rocks, other ships, and personal watercraft.
In addition, the obstacle detection unit 562 may detect obstacles using, for example, a radar (not shown) installed on the ship 10, or may detect whether another ship is located ahead of the hull 12 in the direction of travel from a radio signal emitted from the other ship.

When a failure of the steering mechanism is detected, the movement control unit 564 adjusts the output of the left engine 13A and the right engine 13B so that the hull 12 moves in the desired direction, and adjusts the rotation direction of the left screw propeller 14A and the right screw propeller 14B. In other words, in this embodiment, when the steering mechanism of the ship 10 fails, the traveling direction of the ship 10 is adjusted by the output ratio of the left and right engines 13 and the rotation direction of the screw propeller 14.

The control by the movement control unit 564 will be described in more detail.
When a failure of the rudder mechanism is detected, the movement control unit 564 first determines whether the hull 12 will move straight by making the outputs of the left and right engines 13A, 13B equal as shown typically in Fig. 9A. Note that arrow A in Fig. 9 typically indicates the magnitude of the output of the left engine 13A, and arrow B typically indicates the magnitude of the output of the right engine 13B. The direction of the arrow also indicates the direction of the propulsive force obtained by the rotation of the screw propeller 14, i.e., the rotation direction of the screw propeller 14.
At this time, the output of the left and right engines 13A, 13B is set to, for example, 50% of the maximum output. This is because it is easier to adjust the traveling direction if there is an equal margin in both directions for increasing and decreasing the output of the engine 13. In this case, the normal output of each of the left and right engines 13, which will be described later, is set to 50% or less of the maximum output of the engine 13.

When the hull 12 moves straight ahead with the left and right engines 13A, 13B having equal power, the movement control unit 564 maintains the same power ratio until an instruction to turn the hull 12 is received. In other words, the state in which the power of the left and right engines 13A, 13B is equal (for example, both are 50% of maximum power) is regarded as the normal power (in other words, the power when moving straight ahead).

On the other hand, if the output of the left and right engines 13A, 13B is made equal and the hull 12 turns to the left or right, the movement control unit 564 reduces the output of the engine 13 on the opposite side to the side on which the hull 12 turns relatively.
For example, as shown by the dotted arrow in Fig. 9A, if the output of the left and right engines 13A, 13B is equal, the hull 12 turns to the right, and as shown in Fig. 9B, the output of the left engine 13A, which is opposite to the side on which the hull 12 turns, is reduced. This reduces the thrust of the hull 12 to the right, and when the left and right engines are balanced, the hull 12 moves straight. The movement control unit 564 sets the output of the left and right engines 13 when the hull 12 moves straight as the normal output. For example, if the output of the left and right engines 13A, 13B is 50% of the maximum output in Fig. 9A, the output of the left engine 13A is less than 50% of the maximum output (e.g., 30%) and the output of the right engine 13B is 50% of the maximum output in Fig. 9B, both of which are less than 50% of the maximum output.
Furthermore, if the output of the left and right engines 13A, 13B is made equal, the hull 12 will turn to the left or right, which is thought to be due to, for example, the direction of the rudder 15 being tilted to the left or right at the time a failure occurs in the steering mechanism, or due to factors such as the ocean current at that point.

When the hull 12 is turned to the left or right during subsequent navigation (navigation at normal output), the movement control unit 564 relatively reduces the output of the engine 13 on the side on which the hull 12 is turning. At this time, the movement control unit 564 increases or decreases the output of the engine 13 on the side with the smaller normal output, for example, to create a difference in output between the left and right engines 13. This is because fuel consumption can be reduced compared to increasing or decreasing the output of the engine 13 on the side with the larger normal output, and because the traveling speed is more stable when the engine 13 whose output is increased or decreased is determined.
For example, as shown in Fig. 9B, if the output of the left engine 13A is relatively reduced and the hull 12 travels straight, the engine 13 on the side with the smaller normal output becomes the left engine 13A. In such a sailing state, if it is desired to turn the hull 12 to the left, as shown in Fig. 10A, the movement control unit 564 reduces the output of the left engine 13A, which is on the turning side, to less than the normal output. This causes the output of the right engine 13B to become relatively larger, and the hull 12 turns to the left.
10B, when it is desired to turn the hull 12 to the right, the movement control unit 564 increases the output of the left engine 13A on the opposite side to the turning side from the normal output, and relatively reduces the output of the right engine 13B on the turning side. In Fig. 10B, for example, the outputs of the left engine 13A and the right engine 13B become equal, resulting in the state shown in Fig. 9A, which causes the hull 12 to turn to the right.

In other words, the movement control unit 564 determines the normal output of the left engine 13A, which is the first drive unit, and the right engine 13B, which is the second drive unit, so that the hull 12 moves straight, and when turning the hull 12 to the left or right, increases or decreases the output of either the left engine 13A or the right engine 13B from the normal output.
Furthermore, when turning the hull 12 to the left or right, the movement control unit 564 increases or decreases the output of the engine 13 that normally has a smaller output (the left engine 13A in the example of FIG. 10).

In the above explanation, when determining the normal output, the output of the engine 13 on the side opposite the side on which the hull 12 turns is reduced, but this is not limited to the above, and the output of the engine 13 on the side on which the hull 12 turns may be increased to relatively reduce the output of the engine 13 on the side on which the hull 12 turns.
Specifically, for example, if the output of the left and right engines 13A, 13B is equal, the hull 12 will turn to the right, the output of the right engine 13A, which is on the side where the hull 12 will turn, may be increased, as shown in Figure 9C.
On the other hand, since increasing the output of the engine 13 also increases the amount of fuel used, it is considered preferable to reduce the output of the engine 13 on the opposite side to the turning direction of the hull 12 as shown in Figure 9B, balance the left and right sides, and set the output to normal.

Similarly, in Figure 10, when turning the hull 12 to the left or right, the output of the engine 13 on the side where the hull 12 turns is relatively reduced by increasing or decreasing the output of the engine 13 on the side which normally has less output (the left engine 13A in the example of Figure 10), but the output of the engine 13 on the side where the hull 12 turns may also be relatively reduced by increasing or decreasing the output of the engine 13 on the side which normally has more output (the right engine 13B in the example of Figure 10).
Specifically, when the hull 12 is moving straight ahead by relatively reducing the output of the left engine 13A as shown in Figure 9B, when it is desired to turn the hull 12 to the left, the output of the right engine 13B may be made greater than the normal output, and when it is desired to turn the hull 12 to the right, the output of the right engine 13B may be made less than the normal output.

<Obstacle contact avoidance control>
Next, a case where an obstacle is detected ahead in the traveling direction of the boat 10 will be described.
When the obstacle detection unit 562 detects an obstacle ahead in the traveling direction of the vessel 10, the vessel 10 needs to navigate in a manner that avoids contact with the obstacle.
In this embodiment, the movement control unit 564 navigates the ship 10 in the following two types of methods depending on the distance between the obstacle and the ship 10.

(Method 1) When the distance between the obstacle and the ship 10 is equal to or greater than a predetermined distance L0 Method 1 is used when the distance between the obstacle and the ship 10 is large and the urgency is relatively low. Method 1 may also be applied when the obstacle is a drifting object or the obstacle does not move or moves relatively slowly.
11A, it is assumed that an obstacle 80 is detected at a distance L1 (≧L0) ahead of the ship 10 sailing upward on the paper. In this case, the movement control unit 564 sets the left and right engines 13A, 13B to maximum output and reverses the rotation direction of the left and right screw propellers 14A, 14B to move the hull 12 backward. Since inertia acts on the hull 12 that had been moving forward up until that point, the hull 12 does not immediately start moving backward even when the left and right screw propellers 14A, 14B are reversed, but the hull 12 starts moving backward after a certain time.
When the hull 12 starts to move backward, the movement control unit 564 shifts the direction of the hull 12 to the left or right so that the direction of travel of the ship 10 does not face the obstacle 80. For example, the Maritime Collision Prevention Act stipulates that when two ships meet head-on and there is a risk of collision, each ship passes on the port side (left side of the ship) of the other ship. Here, a case is considered in which the hull 12 is turned to the left side to avoid the obstacle 80. It is generally known that if the left and right screw propellers 14A and 14B of the ship 10 are rotated in opposite propulsion directions, respectively, it is possible to change direction within a very small range. If it is desired to turn the hull 12 to the left using this method, as shown in FIG. 11B, a force is generated that tries to rotate the entire hull 12 to the left around the stern, and the bow faces left.
After changing direction in this manner, the movement control unit 564 navigates the ship 10 while appropriately changing direction so as to return to the original course while avoiding the obstacle 80 as shown in FIG. 11C.

(Method 2) When the distance between the obstacle and the ship 10 is less than a predetermined distance Method 2 is used when the distance between the obstacle and the ship 10 is small and the level of urgency is relatively high. Method 2 may also be applied when the moving speed of the obstacle is relatively fast, for example, when another ship is sailing across the traveling direction of the ship 10.
12A, it is assumed that an obstacle 80 is detected at a distance L2 (<L0) ahead of the ship 10 sailing upward on the paper. In this case, the movement control unit 564, as in method 1, sets the left and right engines 13A, 13B to maximum output and reverses the rotation direction of the left and right screw propellers 14A, 14B to move the hull 12 backward. Since inertia acts on the hull 12 that had been moving forward up until that point, reversing the rotation direction of the left and right screw propellers 14A, 14B does not cause the hull 12 to move backward immediately, but after a certain time, the hull 12 starts to move backward.
When the hull 12 starts to move backward, the movement control unit 564 continues the backward movement of the hull 12. At this time, if the hull 12 is moved straight by making the output of the left and right engines 13A and 13B unbalanced, it is predicted that the hull 12 will turn to the left or right while moving backward. For example, if the hull 12 moves straight forward while making the output of the left engine 13A relatively small as shown in FIG. 9B, if the left and right engines 13A and 13B are both set to maximum output and moved backward, the hull 12 will turn so that the bow faces left as shown in FIG. 12B. In other words, the traveling direction of the hull 12 is not controlled. However, moving away from the obstacle 80 is prioritized until the distance from the obstacle 80 reaches the distance L3.
When the distance to the obstacle 80 reaches distance L3, the movement control unit 564 navigates the ship 10 while appropriately changing direction to return to the original course while avoiding the obstacle 80 as shown in Fig. 12C. Specifically, for example, the ship 10 may navigate along a route W1 that goes around the left side of the obstacle 80, or along a route W2 that goes around the right side of the obstacle 80. Note that distance L3 may be set to be equal to the predetermined distance L0 or longer than the predetermined distance L0.

In other words, when an obstacle is detected ahead of the hull 12 in the direction of travel, the movement control unit 564 rotates the left screw propeller 14A and the right screw propeller 14B in the opposite direction to when moving forward, and moves the hull 12 to go around the obstacle after the distance between the hull 12 and the obstacle becomes equal to or greater than the predetermined distance L0.

<When a propulsion unit is installed on the vessel 10>
FIG. 13 shows another example of the configuration of a ship.
The boat 10A shown in Fig. 13 is equipped with two propulsion units 17 (17A, 17B) in which the engine 13 and the screw propeller 14 are integrated together. The left propulsion unit 17A equipped with the left screw propeller 14A and the left engine 13A is provided on the left side of the hull 12, and the right propulsion unit 17B equipped with the right screw propeller 14B and the right engine 13B is provided on the right side of the hull 12.

The propulsion unit 17 includes an engine 13, a power transmission mechanism 130 (see FIG. 2), and a screw propeller 14. The functions of the engine 13, the power transmission mechanism 130, and the screw propeller 14 are similar to those described with reference to FIGS. 1 and 2.
Among these components, the engine 13 and the power transmission mechanism 130 are housed within the cover 1702 , and the screw propeller 14 is disposed outside the cover 1702 .
As described above, the cover 1702 houses the engine 13 and the power transmission mechanism 130, and is connected to the center of the transom 1206 in the hull width direction so as to be able to swing about the steering axis Z extending in the vertical direction of the hull 12.

In the ship 10 having such a propulsion unit 17, the steering actuators 16A, 16B each swing the propulsion units 17A, 17B together with the case 1702 about the steering axis Z based on an operation angle signal of the handle 22 provided from the ship maneuvering control device 18, thereby changing the steering angle of the propulsion unit 17 (the angle that the axis XL of the propeller shaft 1410 forms with respect to the center line CL of the hull 12) and adjusting the traveling direction of the hull 12. That is, in the ship 10 shown in Fig. 1, the traveling direction of the hull 12 is adjusted by swinging the rudder 15, but in the ship 10 shown in Fig. 13, the traveling direction of the hull 12 is adjusted by swinging the propulsion unit 17 including the engine 13 and the screw propeller 14 together with the case 1702.
In other words, the steering mechanism of the propulsion unit 17 adjusts the direction of movement of the hull 12 by swinging the orientation of the left screw propeller 14A and the right screw propeller 14B relative to the orientation of the hull 12 (center line CL).

Note that, as shown in FIG. 13, there are various types of propulsion unit 17, including an outboard motor in which the engine 13, power transmission mechanism 130, and screw propeller 14 are all attached to the outside of the hull 12, and an inboard-outboard motor (stern drive) in which the engine 13 is installed inside the hull 12 and the screw propeller 14 is installed outside the hull 12 and connected by a power transmission mechanism 130. This embodiment can be applied to any of these types.

In the case where the steering mechanism of one of the propulsion units 17 in the vessel 10 provided with two such propulsion units 17 fails, the following two methods can be adopted.
In addition, in a ship 10 equipped with such a propulsion unit 17, failure of the steering mechanism may occur, for example, when the steering actuator 16A fails, or when a physical defect occurs in the connection mechanism connecting the case of the propulsion unit 17 to the hull 12.

(Method 1) The engine 13 of the propulsion unit 17 on the side where the steering mechanism has failed is stopped, and the ship is navigated using only the propulsion unit 17 on the side where the steering mechanism has not failed.
When the engine 13 of the propulsion unit 17 with a failed rudder mechanism is driven, a propulsive force is generated in the direction of the propulsion unit 17 at the time the rudder mechanism failed. Although the traveling direction of the hull 12 can be adjusted by adjusting the direction of the propulsion unit 17 on the non-failed side, efficiency is reduced due to the propulsive force generated by the failed propulsion unit 17. Therefore, in method 1, the engine 13 of the propulsion unit 17 on the side with the failed rudder mechanism is stopped and the ship is navigated using only the propulsion unit 17 on the non-failed side.
That is, in method 1, in a ship 10A, i.e., a ship 10 that uses propulsion units 17, in which the steering mechanism of either the left or right propulsion unit 17 fails and either the left or right screw propeller 14A or the right screw propeller 14B can no longer move, the movement control unit 564 stops the drive unit (engine 13) that rotates the screw propeller 14 on the failed side, and moves the hull 12 using only the screw propeller 14 on the healthy side and the corresponding engine 13.

(Method 2) The steering mechanism of the propulsion unit 17 on the side where the steering mechanism is not broken is also stopped, and the direction of travel of the ship 10 is adjusted by adjusting the output ratio between the left and right engines 13.
In method 2, the engine 13 of the propulsion unit 17 on the side where the steering mechanism has failed continues to operate, while the rudder mechanism of the propulsion unit 17 on the side where the rudder mechanism has not failed is also stopped from use, and the direction of travel of the ship 10 is adjusted by adjusting the output ratio of the left and right engines 13 as explained using Figures 9 to 12.
By doing so, it is possible to continue navigating using both the left and right engines 13, making it possible to reach the destination more quickly.

As described above, according to the ship navigation system of the embodiment, if the steering mechanism of the ship 10 fails, the direction of travel of the ship 10 is adjusted by changing the output of the left and right drive units (engines 13A, 13B) and the rotation direction of the screw propellers 14A, 14B. This means that the ship 10 can be changed direction even when the steering mechanism fails, which is advantageous in improving the safety of the ship 10.
Furthermore, according to the ship navigation system of the embodiment, the output (normal output) of the left and right engines 13A, 13B is determined so that the hull 12 moves straight ahead, and when turning the hull 12 to the left or right, the output of the left and right engines 13A, 13B is increased or decreased from the normal output, so that the direction of travel of the hull 12 can be adjusted regardless of the steering situation when the rudder mechanism fails.
Furthermore, in the ship navigation system according to the embodiment, when turning the hull 12 to the left or right, increasing or decreasing the output of the engine 13 on the side with the smaller normal output is advantageous in terms of reducing the energy consumption of the engines 13 compared to increasing or decreasing the output of the engine 13 on the side with the larger normal output.
Furthermore, in the ship navigation system according to the embodiment, if the normal output is set to 50% or less of the maximum output of the engine 13, this is advantageous in steadily reducing the energy consumption of the engine 13.
In addition, according to the ship navigation system of the embodiment, when an obstacle is detected ahead of the hull 12 in the direction of travel, the left and right screw propellers 14A, 14B are rotated in the opposite direction to that when moving forward, and the hull 12 is moved to go around the obstacle after the distance between the hull 12 and the obstacle becomes equal to or greater than a predetermined distance, which is advantageous in reliably avoiding contact between the obstacle and the hull 12.
In addition, according to the ship navigation system of the embodiment, in a ship that is steered by swinging the direction of the left and right screw propellers 14A, 14B relative to the hull 12, if a failure of the steering mechanism is detected (such as the screw propeller 14 being unable to move), the engine 13 that rotates the screw propeller 14 on the failed side is stopped, and the hull 12 is moved using only the screw propeller 14 and engine 13 on the healthy side, which is advantageous in adjusting the direction of travel of the hull 12 while reducing energy consumption in the engine 13.
According to the ship navigation system of the embodiment, the actuators 26, 28, 30 for respectively operating the operation members 20, 22, 24 for navigating the ship 10 are provided at locations that do not interfere with manual operation of the operation members 20, 22, 24 by the ship operator seated at the steering seat 1204, and the ship 10 can be remotely operated by controlling the actuators 26, 28, 30 based on remote operation command information to operate the operation members 20, 22, 24 by selecting the remote operation mode of the operation member control unit 66A, and the operation members 20, 22, 24 can be manually operated by selecting the manual operation mode of the operation member control unit 66A. Therefore, it is not necessary to modify the ship 10 in order to perform remote operation, and the ship 10 can be remotely operated, and the ship 10 can be manually operated by sitting at the steering seat 1204 without returning the ship 10 to its original state, which is advantageous in improving usability.

In this embodiment, the remote control control unit 56 functions as the failure control unit 56C, but for example, when the ship 10 is not remotely controlled but is autonomously sailing, the control unit installed on the ship 10 (the ship steering control device 18 in this embodiment) may function as the failure control unit 56C.

In addition, in this embodiment, the vessel 10 is provided with one drive unit (engine 13) on each side, but the present invention can be applied to any vessel that has the same number of drive units on each side. When applying the present invention to a vessel with two or more drive units on each side, the "output of the left engine 13A" in the above embodiment can be replaced with the "sum of the outputs of the drive units provided on the left side," and the "output of the right engine 13B" can be replaced with the "sum of the outputs of the drive units provided on the right side."

LIST OF SYMBOLS 10 Ship 12 Hull 13 (13A, 13B) Engine 14 (14A, 14B) Screw propeller 15 (15A, 15B) Rudder 16 (16A, 16B) Steering actuator 17 (17A, 17B) Propulsion unit 18 Ship maneuvering control device 20 Ignition switch 22 Handle 24 Throttle lever 26 First actuator 28 Second actuator 30 Second actuator 32 Ship-side control device 44 Remote control device 46 First remote control lever 48 Second remote control lever 50 Third remote control lever 54 Mode changeover switch 56 Remote control-side control unit 56A Command information generation unit 56B Notification unit 56C Failure control unit 560 Failure detection unit 562 Obstacle detection unit 564 Movement control unit 58 Remote control-side communication unit 60 Ship-side communication unit 66 Control unit 66A Operation member control unit

Claims (4)

A navigation system for a ship comprising: a first screw propeller provided on a left side of a hull; a first drive unit that rotates the first screw propeller; a second screw propeller provided on a right side of the hull; a second drive unit that rotates the second screw propeller; and a steering mechanism that adjusts a moving direction of the hull,
A failure detection unit that detects a failure of the steering mechanism;
a movement control unit that, when a failure of the steering mechanism is detected, adjusts the outputs of the first drive unit and the second drive unit so that the hull moves in a desired direction, and adjusts the rotation directions of the first screw propeller and the second screw propeller ,
the movement control unit determines normal outputs of the first drive unit and the second drive unit so that the hull moves straight, and when turning the hull to the left or right, increases or decreases the output of the drive unit having the smaller normal output.
A ship navigation system comprising : The movement control unit sets the normal output to 50% or less of the maximum output of the drive unit.
2. A ship navigation system according to claim 1 . An obstacle detection unit that detects an obstacle located ahead of the hull in the traveling direction,
the movement control unit, when the obstacle is detected ahead in the traveling direction of the hull, rotates the first screw propeller and the second screw propeller in a direction opposite to that in the forward traveling direction, and moves the hull so as to detour around the obstacle after the distance between the hull and the obstacle becomes equal to or greater than a predetermined distance.
3. A ship navigation system according to claim 1 or 2 . The vessel,
A plurality of actuators each for operating a plurality of operating members for navigating the marine vessel, the operating members being operated by a pilot;
A ship-side communication unit that receives remote operation command information;
an operation member control unit that operates each of the actuators based on the remote operation command information received by the vessel side communication unit,
the plurality of actuators are provided at locations that do not interfere with manual operation of the operating members by the pilot seated in a pilot's seat,
The operation member control unit is configured to be selectable between a remote operation mode in which the operation members are operated by controlling each of the actuators based on the remote operation command information, and a manual operation mode in which the operator can manually operate each of the operation members.
4. A ship navigation system according to claim 1, wherein the navigation system is a navigation system for a ship.

Images