JP7846567B2 - Ship handling system and ship handling method - Google Patents

Description

This disclosure relates to a method for maneuvering a vessel, particularly when docking, and a maneuvering system for achieving this method.

The entire process from a ship's arrival in port to its berth and mooring involves mentally demanding maneuvering for the operator and physically demanding tasks for onboard crew members. For these reasons, there is a demand for automation and labor-saving measures in this process to reduce the workload and improve safety. However, due to the need for flexible responses to fluctuations in weather and sea conditions within the port, and the need for precise coordination between onboard and port workers, the majority of the work still relies on the experience of the operator and both onboard and port workers.

Patent Document 1 discloses an automatic docking and mooring machine that automates the operation of a vessel from docking to mooring. The vessel in Patent Document 1 comprises a forward and rear thrust engine that outputs forward and rear thrust of the hull, a bow-side thruster and aft-side pod propulsion machine that can output lateral thrust in either direction of the hull, a bow-side mooring machine and aft-side mooring machine that can wind up and unwind mooring lines, a distance meter that measures the distance to the quay, and a controller that controls the bow-side thruster, aft-side pod propulsion machine, bow-side mooring machine and aft-side mooring machine based on the measurement value of the distance meter. The controller performs the docking and mooring operations of the vessel in the order of docking mode and mooring mode. In docking mode, the controller stops the forward and rear thrust engines, bow-side mooring machine and aft-side mooring machine, and moves the hull laterally to a mooring start position 1m from the quay using the bow-side thruster and aft-side pod propulsion machine. In mooring mode, the controller shuts down the forward and rear thrusters, the bow-side thrusters, and the stern-side pod thrusters, and then uses the bow-side and stern-side mooring machines to pull the mooring lines, thereby securing the vessel to the quay.

Japanese Patent Publication No. 2005-255058

When docking (or berthing) a vessel, it is conceivable that the operator may misoperate the control equipment. Such misoperation can cause the vessel to move. If, for example, an error occurs that generates thrust toward the quay when the vessel is sufficiently close to the quay, there is a risk of the vessel colliding with the quay. The likelihood of a collision due to misoperation increases as the distance of the vessel from the quay decreases.

This disclosure is made in light of the above circumstances, and its purpose is to propose a technology that prevents a ship from colliding with a quay even if a malfunction occurs in the steering equipment during docking.

To solve the above problems, a ship handling system according to one aspect of this disclosure is provided.
A plurality of propulsion devices mounted on the hull include a propulsion machine that outputs thrust to push the hull toward the shore and a mooring machine that outputs thrust to push the hull toward the shore by winding up mooring lines,
A distance meter for detecting the docking distance, which is the distance from the hull of the ship to the quay where it is to dock,
Control equipment that outputs propulsion commands,
The system includes a control device that acquires the docking distance and the propulsion command, determines the propulsion command limit value corresponding to the docking distance based on a given relationship in which the propulsion command limit value decreases as the docking distance decreases, sets the propulsion command to the propulsion command limit value if the propulsion command output from the steering device is greater than or equal to the propulsion command limit value, distributes the thrust corresponding to the limited propulsion command to the plurality of propulsion devices, and controls the plurality of propulsion devices so that the thrust distributed from each of the plurality of propulsion devices is output.

A ship handling method relating to one aspect of this disclosure is:
A method for maneuvering a ship equipped with multiple propulsion devices on its hull, including a propulsion machine that outputs thrust to push the hull toward the shore and a mooring machine that outputs thrust to push the hull toward the shore by winding up mooring lines,
The docking distance, which is the distance from the hull to the quay where the ship is to dock, is obtained.
A propulsion command is obtained for the aforementioned hull,
Based on the given relationship that the propulsion command limit decreases as the docking distance decreases, the propulsion command limit corresponding to the docking distance is determined, and the propulsion command is determined to be limited to or less than the propulsion command limit.
The thrust corresponding to the limited propulsion command is distributed to the plurality of propulsion devices,
The system controls the multiple propulsion devices so that the thrust distributed from each of the multiple propulsion devices is output.

According to this disclosure, a technology can be proposed to prevent a ship from colliding with a quay even if a malfunction occurs in the steering equipment while docking.

Figure 1 is a diagram showing a schematic configuration of a vessel to which a ship handling system according to one embodiment of the present disclosure is applied. Figure 2 shows a schematic configuration of the mooring machine. Figure 3 shows the configuration of the ship handling system. Figure 4 is a diagram illustrating the functional components of the ship steering controller. Figure 5 is a diagram illustrating the processing of the propulsion control unit. Figure 6 is a diagram illustrating the maneuvering method when docking or mooring a vessel. Figure 7 is a diagram illustrating an example of the relationship between the docking distance d and the propulsion command limit value Ulim. Figure 8 is a diagram illustrating an example of the relationship between the docking distance d and the propulsion command limit value Ulim. Figure 9 is a diagram illustrating the docking speed Vapp. Figure 10 is a diagram illustrating an example of the relationship between the docking speed Vapp, the approach speed threshold Vsafe (ΔV), and the correction coefficient Kv. Figure 11 illustrates the disturbance force Fapp when docking.

Next, embodiments of this disclosure will be described with reference to the drawings. Figure 1 is a diagram showing the schematic configuration of a vessel S to which a ship handling system 20 according to one embodiment of the present invention is applied.

[Outline of the ship S]
As shown in Figure 1, with the vessel S as the reference point, the horizontal direction connecting the bow and stern of the vessel S is defined as the "forward and backward direction," and the horizontal direction perpendicular to the forward and backward direction (left and right direction) is defined as the "lateral direction." The vessel S comprises a hull 5, at least one forward and backward thruster 2 that outputs thrust in the forward and backward direction relative to the hull 5, and at least one lateral thruster 3 that outputs thrust in the lateral direction relative to the hull 5.

In this embodiment, the forward and rear thrusters 2 include a combination of a variable-pitch propeller and a rudder, which are the main thrusters. The variable-pitch propeller and rudder are mounted on the stern side of the hull 5. However, the forward and rear thrusters 2 are not limited to the above and may be a swivel thruster or a combination of multiple variable-pitch propellers and rudders.

The transverse thruster 3 preferably includes at least one bow-side transverse thruster 3B and at least one stern-side transverse thruster 3A. In this embodiment, the bow-side transverse thruster 3B is a side thruster (bow thruster) located at the bow. Furthermore, in this embodiment, the combination of a variable-pitch propeller and rudder located at the stern can output both longitudinal and transverse thrust depending on the rudder's orientation, thus also functioning as a stern-side transverse thruster 3A. However, the transverse thruster 3 of the vessel S is not limited to the above; side thrusters may be arranged on both the bow and stern sides of the hull 5, or a swivel thruster may be arranged on at least one of the bow and stern sides of the hull 5.

Furthermore, the vessel S includes at least one forward mooring device 10B installed on the bow side of the deck and at least one aft mooring device 10A installed on the stern side of the deck. In this disclosure, the mooring devices 10, the forward and backward propulsion devices 2, and the transverse propulsion devices 3 are collectively referred to as the "propulsion device 9." While the mooring device 10 is originally a device for mooring the vessel S, in the ship handling system 20 of this disclosure, the mooring device 10 also has the function of providing thrust to the vessel S; therefore, the mooring device 10 is also considered a type of propulsion device 9.

In this embodiment, the bow mooring machine 10B includes a headline mooring machine and a forward springline mooring machine. The bow mooring machine 10B may further include a forward breast mooring machine. Furthermore, in this embodiment, the stern mooring machine 10A includes a sternline mooring machine and an aft spring mooring machine. The stern mooring machine 10A may further include an aft breast mooring machine. The number of mooring machines 10 that a vessel S should possess (when the bow mooring machine 10B and the stern mooring machine 10A are not distinguished, the reference numeral 10 is used) is determined by the number of outfitting units, etc.

The forward mooring machine 10B and the aft mooring machine 10A have substantially identical structures. As shown in Figure 2, each mooring machine 10 is equipped with a mooring rope R and a winch W capable of winding and unwinding the mooring rope R. The winch W is electrically hydraulic. The winch W comprises a winding drum 11 around which the mooring rope R is wound, a motor 12 that rotates the winding drum 11, a hydraulic clutch 13 that switches between connecting and disconnecting power transmission from the motor 12 to the winding drum 11, a reduction gear 14 provided on the power transmission path from the motor 12 to the winding drum 11, and a hydraulically released brake 15 that provides constant braking force. However, the structure of the winch W is not limited to the above, and the winch W may also be electrically operated.

The mooring machine 10 is equipped with a rotational position sensor 51, a tension meter 52, a cable length meter 53, and a winch controller 50 that controls the operation of the winch W based on the detected values of these sensors. The rotational position sensor 51 detects the rotational position and rotational speed of the motor 12 or the winding drum 11. The cable length meter 53 measures the length of the mooring cable R unwound from the winding drum 11. The winch controller 50 measures the rotation of the motor 12 or the winding drum 11 based on the detection signal from the rotational position sensor 51 and/or the measurement value from the cable length meter 53, and estimates the winding length and unwinding length of the mooring cable R. The tension meter 52 may directly or indirectly detect the tension (load) acting on the mooring cable R. The tension meter 52 may be, for example, a load cell provided in the brake 15, and the tension of the mooring cable R may be estimated based on the load detected by the load cell. The tension meter 52 is, for example, a torque sensor that detects the output torque of the motor 12, and the tension of the mooring line R may be estimated based on the torque detected by the torque sensor. The winch controller 50 can control the rotation of the winding drum 11 based on the value detected by the tension meter 52 so that the tension acting on the mooring line R is maintained at a predetermined value that does not exceed a predetermined upper limit.

When winding the mooring rope R onto the winding drum 11, the power transmission path from the motor 12 to the winding drum 11 is connected by the clutch 13, and the winding drum 11 is driven to rotate in the winding direction. When the thrust is acting in the away-shore direction, the winding force of the winch W is set to a small value sufficient to suppress slack in the mooring rope R. When unwinding the mooring rope R from the winding drum 11, the clutch 13 is disengaged, disconnecting the power transmission path from the motor 12 to the winding drum 11, allowing the winding drum 11 to rotate freely in the unwinding direction. Alternatively, when unwinding the mooring rope R, the power transmission path from the motor 12 to the winding drum 11 may be connected by the clutch 13, and the winding drum 11 may be driven to rotate in the unwinding direction.

Returning to Figure 1, the end of the mooring rope R is secured to a mooring post 35 installed on the quay 30. The mooring rope R, pulled out from the winding drum 11, is protected and guided by appropriate guide devices 36, such as chocks (mooring holes), fairleads, deck end rollers, and stand rollers.

[Configuration of the ship handling system 20]
Figure 3 shows the configuration of the ship handling system 20. As shown in Figure 3, the ship handling system 20 of the ship S comprises a ship handling controller 6, an instrument group 7, a user interface 8, and a propulsion controller group 9C, all of which are electrically connected to the ship handling controller 6 by wire or wireless means.

The ship steering controller 6 includes a processor, memory such as ROM and RAM, and an I/O unit (none of which are shown). The instrument group 7, user interface 8, and propulsion controller group 9C are connected to the ship steering controller 6 via the I/O unit. Storage (not shown) may also be connected to the ship steering controller 6 via the I/O unit.

The ship handling controller 6 is connected to a ship-to-shore communication device 31. The ship handling controller 6 uses the ship-to-shore communication device 31 to transmit ship handling information to a status monitoring device 33 located at a land base. This ship handling information includes navigation conditions within the harbor and equipment operation data.

The instrument group 7 includes a rangefinder 27, a camera 28, and various navigational instruments.

The distance meter 27 includes a bow-side distance meter for measuring the bow-side distance from the bow to the quay 30, and a stern-side distance meter for measuring the stern-side distance from the quay 30. The distance meter 27 may be a known non-contact distance meter, such as a laser distance meter. The ship handling controller 6 can determine the distance from the hull 5 to the quay 30 in the berthing direction D2 (hereinafter referred to as "berthing distance d") based on the information obtained from the distance meter 27. Here, the berthing direction D2 is the direction towards approaching the quay 30. Furthermore, the berthing distance d may be defined as the shortest distance from the hull 5 to the quay 30.

Camera 28 includes a bow-side camera mounted on the bow deck that continuously or intermittently images the quay 30 from the bow, and a stern-side camera mounted on the stern deck that continuously or intermittently images the quay 30 from the stern. It is desirable that the field of view of the bow-side camera includes the quay 30, as well as the bow-side mooring machine 10B and/or the mooring lines R extended from the bow-side mooring machine 10B. It is also desirable that the field of view of the stern-side camera includes the stern-side mooring machine 10A and/or the mooring lines R extended from the stern-side mooring machine 10A. To ensure such a wide field of view, an around-view camera system may be used as camera 28.

Examples of various navigation instruments include a compass 21 for detecting the ship's heading, a speedometer 22 (water speedometer), anemometer 25 (wind direction and speed meter), a ship position measuring device 26, a current meter 29, an acoustic depth sounder, radar, a chronometer, and a draft gauge. The ship position measuring device 26 is a GPS using satellites or a radio wave and/or optical wave position measuring device using radio waves or light from a reference station. The ship steering controller 6 can obtain navigation information, including the ship's position, course, heading, and speed, based on information acquired from the various navigation instruments.

The ship handling controller 6 uses the ship-to-shore communication device 31 to acquire port information in a timely manner from the port information provision device 32 located at the shore base. Port information includes weather and oceanographic information within the port, as well as port environmental information. Weather and oceanographic information includes wind speed, wind direction, currents, tide levels, weather, and climate within the port. Port environmental information includes congestion levels and berth conditions within the port. The ship handling controller 6 uses the information sent from the port information provision device 32 via the ship-to-shore communication device 31, along with the information from the instrument group 7, for calculations.

The user interface 8 is equipped with control devices 80 and a display device 83. The user interface 8 may further include setting devices and indicators for individual propulsion devices 9 such as propellers and rudders, a display unit for displaying signals from the instrument group 7 such as heading and ship speed indicators, various function selector switches, and indicator lights.

In this embodiment, the control device 80 includes a joystick 81 and a turning dial 82. The joystick 81 receives commands for the direction and magnitude of thrust for the parallel movement of the hull 5, input by the operator moving the joystick 81, and outputs them to the steering controller 6. The turning dial 82 receives commands for the direction and magnitude of the turning moment for turning movement, input by the operator moving the turning dial 82, and inputs them to the steering controller 6. However, the control device 80 is not limited to the above, and known control devices may be used.

As the display device 83, at least one known display device from among various display devices such as touch panel displays and head-mounted displays is employed. The display device 83 may include ship handling support information output from the ship handling controller 6, images captured by the camera 28, equipment operation status, navigation status information, and environmental information of the hull 5 (sea conditions and weather information). The ship handling support information may include at least one of the following: the ship's position on the nautical chart, recommended routes, avoidance lines, remaining distance, sea area facilities, and target positions; the ship's speed vector; and the speed at arbitrary positions on the bow and stern and the remaining distance to the quay 30.

The propulsion controller group 9C controls the operation of the propulsion device 9. Specifically, the propulsion controller group 9C includes a winch controller 50 that controls the winch W of the mooring machine 10, a longitudinal propulsion controller 91 that controls the longitudinal propulsion engines 2, and a transverse propulsion controller 92 that controls the transverse propulsion engines 3. The winch controller 50, longitudinal propulsion controller 91, and transverse propulsion controller 92 are provided according to the number of winches W, longitudinal propulsion engines 2, and transverse propulsion engines 3 installed on the vessel S. However, in Figure 3, only one of the winch controller 50, longitudinal propulsion controller 91, and transverse propulsion controller 92 is shown, and the rest are omitted. The steering controller 6 outputs commands to each of these propulsion controllers in the propulsion controller group 9C, and the propulsion controller group 9C operates the corresponding propulsion device 9 based on the commands.

As shown in Figure 4, the ship handling controller 6 has the following functional units: a ship handling support information generation unit 65, a display control unit 66, a route planning unit 67, a command generation unit 68, and a propulsion control unit 69. The ship handling support information generation unit 65 generates ship handling support information based on information acquired from the instrument group 7 and the port information provision device 32. The display control unit 66 displays the generated ship handling support information on the display device 83. The route planning unit 67 searches for the optimal route that optimizes predetermined evaluation indicators from the departure point to the destination based on information acquired from the instrument group 7 and the port information provision device 32, and generates that optimal route as the planned route. The command generation unit 68 generates commands on behalf of the ship operator during automatic ship handling. The propulsion control unit 69 corresponds to the control device within the scope of the claim. The propulsion control unit 69 controls the propulsion device 9 via the propulsion controller group 9C.

Figure 5 illustrates the processing of the propulsion control unit 69. As shown in Figure 5, the propulsion control unit 69 of the ship steering controller 6 includes an acquirer 61, a limiter 64, a modifier 60, a thrust distribution calculator 62, and an output unit 63.

The data acquisition device 61 acquires information detected or measured by the instrument group 7, commands received by the control equipment 80 of the user interface 8, etc. The information detected or measured by the instrument group 7 includes the docking distance d and docking speed Vapp. The data acquisition device 61 performs A/D conversion, scaling, etc., on the acquired information and commands. Based on the propulsion command received by the joystick 81 (i.e., the tilt angle and tilt direction of the joystick 81), the data acquisition device 61 generates a "command vector." The direction of the command vector corresponds to the tilt direction of the joystick 81, and the magnitude of the command vector corresponds to the tilt angle of the joystick 81. Here, if the propulsion command is a thrust command, the command vector is defined as representing the thrust command to be applied to the hull 5 in terms of direction and magnitude. If the propulsion command is a speed command, the command vector is defined as representing the speed command of the hull 5 in terms of direction and magnitude.

The limiter 64 restricts the command vector as needed based on the docking distance d. The function of the limiter 64 will be described in detail later. Note that the limiter 64 may restrict not only the command vector based on the command received by the control equipment 80, but also the command vector generated by the command generation unit 68.

The modifier 60 acquires disturbance information, including the tidal current detected by the current meter 29, the wind direction and speed detected by the wind direction and speed meter 25, and/or the tidal current and wind direction and speed within the harbor obtained from the harbor information device 32. Based on the disturbance information, it estimates the disturbance force acting on the vessel S and modifies the command vector by adding a force that opposes the disturbance force to the command vector.

The thrust distribution calculator 62 performs calculations to distribute thrust to each of the multiple propulsion devices 9 (mooring machine 10, forward/rear propulsion machines 2, and lateral propulsion machines 3) so that the modified command vectors correspond to the thrust vectors. Here, the mooring machine 10 is considered to be a propulsion device 9 that outputs thrust to push the hull 5 toward the shore in the direction D2 by winding up the mooring rope R. The "thrust vector" is defined as the combined force of the thrusts output from the multiple propulsion devices 9 (mooring machine 10, forward/rear propulsion machines 2, and lateral propulsion machines 3), expressed in terms of direction and magnitude. The thrust distribution calculation method by the thrust distribution calculator 62 will be described in detail later.

The output unit 63 outputs the thrust allocated to each propulsion device 9 (forward/rear thrusters 2, lateral thrusters 3, mooring machine 10), as determined by the thrust distribution calculator 62, as an operation command to the corresponding propulsion controller group 9C (winch controller 50, forward/rear thrust controller 91, and lateral thrust controller 92) after scaling, D/A conversion, and error handling. This applies a thrust to the hull 5 in the direction of tilt, with a magnitude corresponding to the tilt angle of the joystick 81.

[Ship handling method]
Here, the method of maneuvering a vessel S during docking and mooring using the above-described maneuvering system 20 will be explained with reference to Figure 6.

<Approach and Maneuvering>
The ship handling controller 6 begins approach maneuvering when the vessel S enters the harbor. During approach maneuvering, the ship handling controller 6 generates approach maneuvering support information using information acquired from the instrument group 7 and the harbor information provider 32, and displays it on the screen of the display device 83. Here, the ship handling controller 6 sets a predetermined berthing start position P2 as the target position and uses information acquired from the instrument group 7 and the harbor information provider 32 to determine the optimal route from the harbor entrance P1 to the berthing start position P2 as the planned route. On the screen of the display device 83, the approach maneuvering support information is graphically displayed as a harbor chart with the planned route consisting of multiple waypoints, the target position and the vessel's position overlaid, as well as navigation information such as the ship's bearing angle and ship speed. The docking start position P2 is located at a predetermined distance (for example, about 30 to 50 m) from the quay wall 30 of the berth. When the vessel S reaches the docking start position P2, its hull 5 is approximately parallel in the longitudinal direction to the extension direction of the quay wall 30 (hereinafter referred to as "quay wall direction D1"), and its longitudinal speed is approximately zero.

The operator controls the joystick 81 and the turning dial 82 based on the approach maneuvering support information displayed on the display device 83. The maneuvering controller 6 determines the command vector based on the tilt angle and tilt direction of the joystick 81. However, the vessel S may be automatically maneuvered for approach. In this case, the maneuvering controller 6 may generate the command vector itself based on information acquired from the instrument group 7 and the port information provision device 32, as well as the planned route.

The steering controller 6 obtains a modified command vector by adding a force to counteract the disturbance force to the command vector, and distributes thrust to the forward and rear propulsion engines 2 so that a thrust vector corresponding to the modified command vector is obtained by combining the thrusts output from the forward and rear propulsion engines 2. During approach maneuvering, the thrust distributed to the transverse propulsion engines 3 and the mooring engine 10 is zero. The steering controller 6 generates a thrust target value such that the distributed thrust is output and outputs it to the forward and rear propulsion controller 91. The forward and rear propulsion controller 91 controls the forward and rear propulsion engines 2 so that the thrust corresponding to the thrust target value is output. As a result, the vessel S obtains thrust corresponding to the command vector and navigates along the planned route.

<Docking and maneuvering>
The ship handling controller 6 initiates docking maneuvers when the vessel S reaches the docking start position P2. During docking maneuvers, the ship handling controller 6 generates docking support information using information acquired from the instrument group 7 and the port information provider 32, and displays it on the screen of the display device 83. In docking maneuvers, the vessel S is moved from the docking start position P2 to a predetermined mooring start position P3. The mooring start position P3 is located a few to tens of meters away from the berth's quay 30, and when the vessel S reaches the mooring start position P3, its hull 5 is approximately parallel to the quay direction D1 in the forward and backward directions, and its velocity in the forward and lateral directions is approximately zero. The screen of the display device 83 displays docking support information such as a harbor chart with the target position and the vessel's position overlaid, navigation information such as the bow bearing and ship speed, docking distance d, and images captured by the camera 28.

The operator controls the joystick 81 and the turning dial 82 based on the docking assistance information displayed on the display device 83. The ship handling controller 6 determines a command vector based on the tilt angle and tilt direction of the joystick 81. However, the vessel S may be docked automatically. In this case, the ship handling controller 6 may generate the command vector itself based on information acquired from the instrument group 7 and the port information providing device 32.

The steering controller 6 obtains a modified command vector by adding a force to counteract the disturbance force to the command vector, and distributes thrust to the forward and rear propellers 2 and the lateral propellers 3 so that a thrust vector corresponding to the modified command vector is obtained by combining the thrusts output from the forward and rear propellers 2 and the lateral propellers 3. During docking maneuvers, the thrust distributed to the mooring machine 10 is zero. The steering controller 6 generates and outputs thrust target values such that the allocated thrust is output to each of the forward and rear propeller controllers 91 and the lateral propeller controller 92. The forward and rear propeller controller 91 controls the forward and rear propellers 2 so that the thrust corresponding to the given thrust target value is output, and the lateral propeller controller 92 controls the lateral propeller 3 so that the thrust corresponding to the given thrust target value is output. As a result, the vessel S obtains thrust corresponding to the command vector and moves mainly laterally to the mooring start position P3.

<Mooring and handling>
When the vessel S reaches the mooring start position P3, the mooring rope R is extended from the stern mooring machine 10A and the bow mooring machine 10B, and the tip of the mooring rope R is secured to the mooring post 35 provided on the quay 30. During this time, the steering controller 6 uses its automatic heading hold function to keep the vessel S at the mooring start position P3. The automatic heading hold function of the steering controller 6 performs PID calculations on the deviation between the set heading angle and the heading angle from the compass 21, and uses this as a turning moment command in place of the turning dial 82 to calculate the thrust distribution, thereby operating the forward and backward propulsion engines 2 and the transverse propulsion engines 3 to maintain the heading of the bow.

The ship handling controller 6 begins mooring after all mooring lines R are secured to the mooring posts 35 on the quay 30. The ship handling controller 6 generates mooring assistance information using information acquired from the instrument cluster 7 and the port information provider 32, and displays it on the display device 83. The display device 83 displays berthing assistance information, including a harbor chart with the target position and the ship's position overlaid, navigation information such as the ship's bearing angle and speed, berthing distance d, and images captured by the camera 28.

The operator visually confirms the mooring assistance information displayed on the display device 83 and operates the joystick 81 and turn dial 82 of the steering device 80. The joystick 81 and turn dial 82 receive the operator's input and transmit it to the steering controller 6. However, mooring may be performed automatically. If mooring is performed automatically, the steering controller 6 generates a command vector based on information acquired from the instrument group 7 and the port information provision device 32, and the operator can modify the command vector generated by the steering controller 6 using the steering device 80.

The acquisition device 61 of the ship handling controller 6 acquires the propulsion command received by the steering device 80, such as the joystick 81, and generates a command vector. In principle, during mooring, a lateral thrust acts on the ship S, causing the ship S to move in the docking direction D2. Therefore, when the propulsion command Uc is a thrust command, the command vector during mooring is a vector pointing in the docking direction D2 with a thrust of the magnitude corresponding to the propulsion command. Similarly, when the propulsion command Uc is a speed command, the command vector during mooring is a vector pointing in the docking direction D2 with a speed of the magnitude corresponding to the propulsion command Uc.

During mooring operations, the propulsion command Uc is restricted by the limiter 64 of the maneuvering controller 6. For example, the limiter 64 may be configured to restrict the propulsion command Uc when the docking distance d is less than a predetermined limit distance. The limit distance may be the distance from the quay 30 to the mooring start position P3, or a shorter distance.

The limiter 64 is pre-programmed with information representing the relationship between the docking distance d and the propulsion command limit value Ulim. Based on this information, the limiter 64 determines the propulsion command limit value Ulim.

Figure 7 is a diagram illustrating an example of the relationship between the docking distance d and the propulsion command limit value Ulim when the propulsion command Uc is a thrust command. The propulsion command limit value Ulim, as illustrated in Figure 7, is constant at a first value Up from docking distance d to the first threshold dth1, increases with increasing docking distance d from the first threshold dth1 to the second threshold dth2, and remains constant at the command maximum value Umax when docking distance d is greater than or equal to the second threshold dth2. The first value Up is greater than 0 and corresponds to the thrust that presses the hull 5 against the quay 30.

Figure 8 is a diagram illustrating an example of the relationship between the docking distance d and the propulsion command limit value Ulim when the propulsion command Uc is a speed command in the lateral direction (i.e., the docking direction D2) of the vessel S. The propulsion command limit value Ulim, as illustrated in Figure 8, is a first value Up when the docking distance d is 0, increases with increasing docking distance d up to a threshold dth, and remains constant at the maximum command value Umax when the docking distance d is greater than or equal to the threshold dth. A first value Up greater than 0 corresponds to the speed at which the hull 5 is pressed against the quay 30. Alternatively, the first value Up may be 0.

The limiter 64 compares the propulsion command Uc with the calculated propulsion command limit value Ulim. If the propulsion command Uc is less than or equal to the propulsion command limit value Ulim, no limit is placed on the propulsion command Uc (or it is limited to zero). On the other hand, if the propulsion command Uc is greater than the propulsion command limit value Ulim, the limiter 64 places a limit on the propulsion command Uc and replaces it with the propulsion command limit value Ulim. In other words, the propulsion command Uc is limited to less than or equal to the propulsion command limit value Ulim, regardless of the value of the input command.

As described above, the limiter 64 restricts the propulsion command Uc. For example, even if the steering input of the control device 80 is excessive due to a pilot error, the propulsion command Uc is restricted to prevent the vessel S from colliding with the quay 30.

As described above, the command vector (i.e., the propulsion command Uc) processed by the limiter 64 is modified by the modifier 60 by adding a force to counteract the disturbance force.

The thrust distribution calculator 62 acquires the modified command vector and distributes the thrust to the multiple propulsion devices 9 so that the combined thrust output from the multiple propulsion devices 9 yields a thrust vector corresponding to the modified command vector. More specifically, the thrust distribution calculator 62 generates thrust target values such that the allocated thrust is output to each of the winch controller 50, longitudinal propulsion controller 91, and lateral propulsion controller 92. The output device 63 outputs the generated thrust target values to each of the propulsion controller group 9C.

The winch controller 50 controls the winding force or winding speed of the mooring machine 10 so that it outputs a thrust corresponding to a given thrust target value. Specifically, the winch controller 50 controls the winding force or winding speed of the winch W so that the thrust target value is obtained by adjusting the tension and length of the mooring rope R by winding in or unwinding it. The forward/reverse propulsion controller 91 controls the forward/reverse propulsion engines 2 so that it outputs a thrust corresponding to a given thrust target value. The transverse propulsion controller 92 controls the transverse propulsion engine 3 so that it outputs a thrust corresponding to a given thrust target value. As a result, the vessel S obtains the thrust corresponding to the modified command vector and moves mainly laterally until it docks.

In thrust distribution during mooring operations, priority is given to the distribution of thrust to the mooring machine 10. Each mooring machine 10 has a set tolerance range for the tension of the mooring rope R. After mooring operations begin and the deflection of the mooring rope R is eliminated by the winding operation of the mooring machine 10, thrust is distributed to the mooring machine 10 so that the tension of the mooring rope R, as measured by the tension meter 52, is maintained within the tolerance range. Here, the tolerance range for tension is greater than 0 and less than a predetermined threshold that is less than the maximum winding force of the mooring machines 10A and 10B. The maximum winding force of the mooring machines 10A and 10B is a known value specific to each of the mooring machines 10A and 10B. A threshold (tolerance range) for the tension of the mooring rope R may be set individually for each of the mooring machines 10A and 10B. Alternatively, the same threshold value (tolerance range) for the tension of the mooring line R may be set for all mooring machines 10A and 10B.

In thrust distribution during mooring operations, thrust is first distributed to each mooring machine 10 so that the tension of each mooring line R is maintained within an acceptable range. Then, the combined thrust vector (mooring machine thrust vector) output by all mooring machines 10 is calculated, and the deficit obtained by subtracting the mooring machine thrust vector from the command vector is compensated for by the thrust output from the forward and rear propulsion machines 2 and the transverse propulsion machines 3. If no deficit occurs, the thrust output from the forward and rear propulsion machines 2 and the transverse propulsion machines 3 may be zero. Through this thrust distribution, the maneuvering controller 6 controls the propulsion devices 9 so that, at least for a portion of the mooring operation, the bow mooring machine 10B and the stern mooring machine 10A perform the winding operation of the mooring line R, while simultaneously causing at least one of the forward and rear propulsion machines 2 and the transverse propulsion machines 3 to output thrust that reduces the tension of the mooring line R.

Furthermore, it is not necessary to generate thrust from all mooring machines 10 installed on the vessel S during mooring operations. For example, thrust may be generated only from one stern mooring machine 10A and one bow mooring machine 10B, while the remaining mooring machines 10 are controlled to maintain a constant tension in the mooring rope R, preventing slack in the rope and not hindering the generated thrust.

[Variation 1]
The limiter 64 of the propulsion device 9 described above determines the propulsion command limit value Ulim based on the docking distance d, but the propulsion command limit value determined based on the docking distance d may be corrected by the docking speed Vapp of the vessel S.

Figure 9 illustrates the berthing speed Vapp. As shown in Figure 9, the berthing speed Vapp is the component of the ship S's speed V in the berthing direction D2. The berthing speed Vapp can be determined using the ship S's speed V detected by the speedometer 22, the ship S's heading angle detected by the compass 21, and pre-stored ship model and quay information.

The limiter 64 of the propulsion control unit 69 corrects the propulsion command limit value Ulim so that it decreases as the speed Vapp of the hull 5 in the docking direction D2 increases.

For example, when the propulsion command limit value Ulim is corrected by a correction coefficient Kv, the corrected propulsion command limit value Ulim is expressed as propulsion command limit value Ulim × correction coefficient Kv. The correction coefficient Kv is a value of 1 or less and is inversely proportional to the difference ΔV between the docking speed Vapp and a predetermined approach speed threshold Vsafe. If the hull 5 moving at or below the approach speed threshold Vsafe comes into contact with the quay 30, no damage will occur to the hull 5. However, if the hull 5 moves beyond the approach speed threshold Vsafe and collides with the quay 30, damage to the hull 5 may occur. Figure 10 is a diagram illustrating an example of the relationship between the docking speed Vapp, the approach speed threshold Vsafe difference ΔV, and the correction coefficient Kv. As illustrated in Figure 10, as the difference ΔV between the docking speed Vapp and the approach speed threshold Vsafe increases, the value of the correction coefficient Kv decreases. Therefore, the propulsion command limit value Ulim corrected by the docking speed Vapp decreases as the difference ΔV between the docking speed Vapp and the approach speed threshold Vsafe increases. The limiter 64 can apply a limit to the propulsion command Uc using the propulsion command limit value Ulim, which has been corrected in this way.

[Variation 2]
The limiter 64 of the propulsion device 9 described above determines the propulsion command limit value Ulim based on the docking distance d, but the propulsion command limit value Ulim determined based on the docking distance d may be corrected by the disturbance force acting on the ship S in the docking direction D2 (hereinafter referred to as "docking disturbance force Fapp").

Figure 11 is a diagram illustrating the berthing disturbance force Fapp. As shown in Figure 11, the berthing disturbance force Fapp is the berthing direction D2 component of the disturbance force F acting on the vessel S. The disturbance force F may include at least one of the hydrodynamic force exerted by water on the hull 5 and the wind pressure exerted by wind on the hull 5. The hydrodynamic force can be calculated, for example, based on the current measured by the current meter 29 and a pre-stored hull model. Alternatively, the hydrodynamic force can be calculated based on the current and tide level in the harbor included in the meteorological and oceanographic information and a pre-stored hull model. The wind pressure can be calculated, for example, based on the wind direction and wind speed measured by the anemometer 25 and a hull model. Alternatively, the wind pressure can be calculated based on the wind speed and wind direction in the harbor included in the meteorological and oceanographic information and a pre-stored hull model. The berthing disturbance Fapp can be determined using the hydrodynamic force and wind pressure, the bow azimuth angle of the vessel S detected by the compass 21, and pre-stored vessel model and quay information.

The limiter 64 of the propulsion control unit 69 acquires disturbance information, including wind direction, wind speed, and tidal currents, in the environment surrounding the hull 5. Based on this disturbance information, it estimates the disturbance force acting on the hull 5 in the docking direction D2 (docking disturbance force Fapp), and corrects the propulsion command limit value according to the docking disturbance force Fapp.

For example, when the propulsion command limit value Ulim is corrected by a correction value Kf, the corrected propulsion command limit value Ulim is expressed as [propulsion command limit value Ulim - disturbance correction value Kf]. The disturbance correction value Kf is proportional to the docking disturbance force Fapp. A positive disturbance correction value Kf represents a disturbance force that propels the movement of the vessel S in the docking direction D2, while a negative disturbance correction value Kf represents a disturbance force that hinders the movement of the vessel S in the docking direction D2 (i.e., promotes movement in the undocking direction D3). The relationship between the docking disturbance force Fapp and the disturbance correction value Kf is predetermined, and the limiter 64 can determine the disturbance correction value Kf based on the docking disturbance force Fapp, and further determine the propulsion command limit value Ulim corrected by the disturbance correction value Kf. Thus, the propulsion command limit value Ulim, corrected by the berthing disturbance force Fapp, increases as the absolute value of the berthing disturbance force Fapp increases when the berthing disturbance force Fapp promotes the movement of the vessel S in the direction away from the berthing D3 (i.e., when the disturbance correction value Kf is negative). On the other hand, the propulsion command limit value Ulim, corrected by the berthing disturbance force Fapp, decreases as the absolute value of the berthing disturbance force Fapp increases when the berthing disturbance force Fapp promotes the movement of the vessel S in the direction of berthing D2 (i.e., when the disturbance correction value Kf is positive).

[Summary]
The ship handling system 20 relating to the first item of this disclosure is
Multiple propulsion devices 9 mounted on the hull 5 include propulsion machines 2 and 3 that output thrust to push the hull 5 in the docking direction D2, and a mooring machine 10 that outputs thrust to push the hull 5 in the docking direction D2 by winding up the mooring rope R,
A distance meter 27 detects the docking distance d, which is the distance from the hull 5 to the quay 30 where the ship is to dock.
A control device 80 that outputs the propulsion command Uc,
The system is characterized by comprising: a control device 69 that acquires the docking distance d and the propulsion command Uc, determines the propulsion command limit value Ulim corresponding to the docking distance d based on a given relationship in which the propulsion command limit value Ulim decreases as the docking distance d decreases, sets the propulsion command Uc to the propulsion command limit value Ulim if the propulsion command Uc output from the steering device 80 is greater than or equal to the propulsion command limit value Ulim, distributes the thrust corresponding to the limited propulsion command Uc to a plurality of propulsion devices 9, and controls the plurality of propulsion devices 9 so that the thrust distributed from each of the plurality of propulsion devices 9 is output.

In the above-described ship handling system 20, regardless of the value of the propulsion command Uc output by the steering device 80 and acquired by the control device 69, the value of the propulsion command Uc is limited to a value less than or equal to the propulsion command limit value Ulim. Since the propulsion command limit value Ulim becomes smaller as the ship 5 approaches the quay 30, even if the steering device 80 is misoperated when the ship 5 is close to the quay 30, the propulsion command Uc is limited to a sufficiently small value, thus preventing the ship 5 from colliding with the quay 30.

The ship handling system 20 according to the second item of this disclosure further includes a speedometer 22 for detecting the speed V of the hull 5, in addition to the ship handling system 20 according to the first item, and the control device 69 corrects the propulsion command limit value Ulim to decrease as the speed Vapp of the hull 5 in the docking direction D2 increases.

In the above-described ship handling system 20, the docking speed Vapp of the hull 5 is added to the propulsion command limit value Ulim, so the propulsion command Uc can be limited to more reliably prevent the hull 5 from colliding with the quay 30.

The ship handling system 20 relating to the third item of this disclosure is a ship handling system 20 relating to the first or second item, in which the control device 69 acquires disturbance information of the environment in which the hull 5 is located, estimates the disturbance force Fapp acting on the hull 5 in the docking direction D2 based on the disturbance information, and corrects the propulsion command limit value Ulim according to the disturbance force Fapp. The disturbance information may include, for example, wind direction, wind speed, and tidal currents.

In the above-described ship handling system 20, the docking disturbance force Fapp acting on the hull 5 is added to the propulsion command limit value Ulim, allowing the propulsion command Uc to be limited in a way that more reliably prevents the hull 5 from colliding with the quay 30.

The ship handling system 20 according to the fourth item of this disclosure further comprises a tension meter 52 for measuring the tension of the mooring line R, in addition to the ship handling system 20 according to any of the first to third items, and the control device 69 distributes thrust corresponding to the propulsion command to a plurality of propulsion devices 9 so that the tension of the mooring line R measured by the tension meter 52 is maintained within a predetermined threshold range that is greater than 0 and less than the maximum winding force of the mooring machine 10.

In the above-described ship handling system 20, while the mooring machine 10 is winding up the mooring rope R in order to bring the hull 5 to the shore, the tension range of the mooring rope R is maintained, thereby preventing overloading of the mooring rope R.

The fifth method of maneuvering a ship is a method of maneuvering a ship S equipped with a plurality of propulsion devices 9 on the hull 5, including propulsion machines 2 and 3 that output thrust to push the hull 5 in the docking direction D2, and a mooring machine 10 that outputs thrust to push the hull 5 in the docking direction D2 by winding up a mooring rope R,
The docking distance d is obtained, which is the distance from the hull 5 to the quay 30 where the ship is to dock.
A propulsion command Uc is obtained for hull 5.
Based on the given relationship that the propulsion command limit value Ulim decreases as the docking distance d decreases, we determine the propulsion command limit value Ulim corresponding to the docking distance d, and then determine the propulsion command Uc that is limited to or less than the propulsion command limit value Ulim.
Thrust corresponding to the limited propulsion command Uc is distributed to multiple propulsion devices 9.
The system is characterized by controlling the multiple propulsion devices 9 so that thrust distributed from each of the multiple propulsion devices 9 is output.

In the above maneuvering method, regardless of the initially acquired value of the propulsion command Uc, the value of the propulsion command Uc is limited to a value below the propulsion command limit value Ulim. Since the propulsion command limit value Ulim decreases as the hull 5 approaches the quay 30, even if the steering equipment 80 is misoperated while the hull 5 is close to the quay 30, the propulsion command Uc is limited to a sufficiently small value, thus preventing the hull 5 from colliding with the quay 30.

The functions of the ship handling controller 6 disclosed herein can be performed using general-purpose processors, dedicated processors, integrated circuits, ASICs (Application Specific Integrated Circuits), conventional circuits, and/or combinations thereof, or processing circuits configured or programmed to perform the disclosed functions. A processor is considered a processing circuit or circuit because it includes transistors and other circuits. In this disclosure, a circuit, unit, or means is hardware that performs the enumerated functions. The hardware may be hardware disclosed herein, or other known hardware programmed or configured to perform the enumerated functions. If the hardware is a processor considered to be a type of circuit, the circuit, means, or unit is a combination of hardware and software, and the software is used to configure the hardware and/or processor.

The discussions of this disclosure described above are presented for illustrative and explanatory purposes only and are not intended to limit the disclosure to the forms disclosed herein. For example, in the detailed description above, various features of the disclosure are grouped into a single embodiment for the purpose of streamlining the disclosure, but some of the features may be combined. Furthermore, some of the features included in this disclosure may be combined into alternative embodiments, configurations, or aspects other than those discussed above.

2: Propulsion unit 3: Propulsion unit 5: Hull 9: Propulsion device 10: Mooring machine 20: Maneuvering system 22: Speedometer 27: Rangefinder 30: Quay 52: Tension meter 69: Propulsion control unit (control device)
80: Control equipment D2: Docking direction

Claims (5)

A plurality of propulsion devices mounted on the hull include a propulsion machine that outputs thrust to push the hull toward the shore and a mooring machine that outputs thrust to push the hull toward the shore by winding up mooring lines,
A distance meter for detecting the docking distance, which is the distance from the hull of the ship to the quay where it is to dock,
Control equipment that outputs propulsion commands,
The system includes: a control device that acquires the docking distance and the propulsion command, determines the propulsion command limit value corresponding to the docking distance based on a given relationship in which the propulsion command limit value decreases as the docking distance decreases, sets the propulsion command to the propulsion command limit value if the propulsion command output from the steering device is greater than or equal to the propulsion command limit value, distributes the thrust corresponding to the limited propulsion command to the plurality of propulsion devices, and controls the plurality of propulsion devices so that the thrust distributed from each of the plurality of propulsion devices is output;
Ship steering system. The vessel further comprises a speedometer for detecting the speed of the hull,
The control device corrects the propulsion command limit value so that it decreases as the speed of the hull in the docking direction increases.
The ship handling system according to claim 1. The control device acquires disturbance information of the environment in which the hull is located, estimates the disturbance force acting on the hull in the docking direction based on the disturbance information, and corrects the propulsion command limit value according to the disturbance force.
The ship handling system according to claim 1 or 2. The system further includes a tension meter for measuring the tension of the mooring line,
The control device distributes thrust corresponding to the propulsion command to the plurality of propulsion devices such that the tension of the mooring line, as measured by the tension meter, is maintained within a range below a predetermined threshold that is greater than zero and less than the maximum winding force of the mooring machine.
The ship handling system according to claim 1 or 2. A method for maneuvering a ship equipped with multiple propulsion devices on its hull, including a propulsion machine that outputs thrust to push the hull toward the shore and a mooring machine that outputs thrust to push the hull toward the shore by winding up mooring lines,
The docking distance, which is the distance from the hull to the quay where the ship is to dock, is obtained.
A propulsion command is obtained for the aforementioned hull,
Based on the given relationship that the propulsion command limit decreases as the docking distance decreases, the propulsion command limit corresponding to the docking distance is determined, and the propulsion command is determined to be limited to or less than the propulsion command limit.
The thrust corresponding to the limited propulsion command is distributed to the plurality of propulsion devices,
The propulsion devices are controlled so that the thrust distributed from each of the propulsion devices is output.
Ship handling methods.