Ship control device, ship control support device, ship control method, and ship control program

Abstract

This technology improves the accuracy of predictions using hull models, enabling appropriate ship control. [Solution] The ship control device 10 includes a reception unit 12 that receives navigation instructions, a storage unit 14 that stores multiple hull models, a setting unit 18 that sets a target hull model from the multiple hull models based on the current status of the ship, a generation unit 20 that generates ship control command values ​​based on the navigation instructions and the target hull model, and an output unit 22 that outputs control signals based on the control command values.

Description

[Technical Field]

[0001] The present invention relates to a ship control device, a ship control support device, a ship control method, and a ship control program. [Background technology]

[0002] Autopilot technology for ships is known (for example, Patent Document 1). In this technology, the difference between the ship's actual position and its planned position is calculated periodically, and the external force acting on the ship is estimated by statistically processing the amount of this difference obtained over time. In this technology, the next steering command for the ship is calculated from the above external force, the actual position, and the target position on the planned route. [Prior art documents] [Patent Documents]

[0003] [Patent Document 1] Japanese Patent Application Publication No. 58-82311 [Overview of the project] [Problems that the invention aims to solve]

[0004] Because ships are very large moving objects, their response to control commands is very slow, and they are easily affected by external environmental factors such as currents and wind. Therefore, with the technology described in Patent Document 1, it was difficult to accurately control the ship's speed and position. Thus, it is conceivable to predict the ship's motion using a hull model simulation and control the ship using the prediction results. However, because the forces acting on the ship and the results of ship control differ depending on the current conditions such as ship speed and water depth at the ship's position, there are limitations to the accuracy of predictions using a single hull model.

[0005] In view of the above issues, the object of the present invention is to provide a technology that improves the accuracy of predictions using a hull model and enables appropriate ship control. [Means for solving the problem]

[0006] To solve the above problems, a ship control device according to one aspect of the present invention comprises: a receiving unit for receiving navigation instructions; a storage unit for storing a plurality of hull models; a setting unit for setting a target hull model from the plurality of hull models based on the current status of the ship; a generation unit for generating ship control command values ​​based on the navigation instructions and the target hull model; and an output unit for outputting control signals based on the control command values.

[0007] Another aspect of the present invention is a ship control support device. This device comprises a communication unit capable of communicating with a ship control device installed on a ship, a storage unit for storing a plurality of ship hull models, a setting unit for setting a target ship hull model from the plurality of ship hull models based on the current status of the ship, a generation unit for generating control command values ​​based on navigation instructions and the target ship hull model, and an output unit for outputting control signals based on the control command values ​​to the ship control device.

[0008] A further aspect of the present invention is a ship control method. This method is a method for controlling a ship control device installed on a ship, or a ship control support device that can communicate with the ship control device, and includes the steps of: receiving a navigation instruction; setting a target hull model from a plurality of hull models based on the current status of the ship; generating a ship control command value based on the navigation instruction and the target hull model; and outputting a control signal based on the control command value.

[0009] A further aspect of the present invention is a ship control program. This program is for controlling a ship control device installed on a ship, or a ship control support device that can communicate with the ship control device, and causes a computer to perform the steps of: receiving a navigation instruction; setting a target ship model from a plurality of ship models based on the current status of the ship; generating a ship control command value based on the navigation instruction and the target ship model; and outputting a control signal based on the control command value.

[0010] In addition, any combination of the above, or those obtained by mutually substituting the components and expressions of the present invention among methods, apparatuses, programs, temporary or non-temporary storage media recording the programs, systems, etc. are also effective as aspects of the present invention.

Effects of the Invention

[0011] According to the present invention, it is possible to improve the accuracy of prediction using a hull model and perform appropriate ship control.

Brief Description of the Drawings

[0012] [Figure 1] It is a diagram schematically showing a ship to which a ship control device according to the first embodiment is applied. [Figure 2] It is a block diagram schematically showing the ship control device of FIG. 1. [Figure 3] It is a diagram showing an example of a method for setting a set hull model by a setting unit. [Figure 4] It is a flowchart showing an example of the operation of the ship control device of FIG. 1. [Figure 5] It is a flowchart showing another example of the operation of the ship control device of FIG. 1. [Figure 6] It is a flowchart showing yet another example of the operation of the ship control device of FIG. 1. [Figure 7] It is a diagram schematically showing a ship to which a ship control system according to the second embodiment is applied. [Figure 8] It is a block diagram schematically showing the ship control system of FIG. 7. [Figure 9] It is a block diagram schematically showing a ship control device according to the third embodiment. [Figure 10] It is a diagram showing an example of a penalty term corresponding to a weighting factor adjusted for each navigation situation. [Figure 11] It is a flowchart showing an example of the operation of the ship control device of FIG. 9.

Modes for Carrying Out the Invention

[0013] Among the embodiments disclosed herein, those composed of multiple objects may be integrated, and conversely, those composed of a single object may be divided into multiple objects. Whether or not they are integrated, the invention can be constructed in a way that achieves its objective.

[0014] In the embodiments disclosed herein, those in which multiple functions are provided in a distributed manner may have some or all of those multiple functions integrated into a single unit, and conversely, those in which multiple functions are integrated may have some or all of those functions provided in a distributed manner. Whether the functions are integrated or distributed, the configuration should be such that the objective of the invention can be achieved.

[0015] Furthermore, separate components that share common characteristics are distinguished by adding "1st," "2nd," etc., to the beginning of their names, and these are omitted when referring to them collectively. In addition, terms containing ordinal numbers such as "1st," "2nd," etc., are used to describe various components, but these terms are used solely for the purpose of distinguishing one component from others, and do not limit the components themselves.

[0016] The present disclosure will be described below with reference to the drawings, based on preferred embodiments. In embodiments and modifications, the same or equivalent components and members will be denoted by the same reference numerals, and redundant descriptions will be omitted as appropriate. In addition, the dimensions of members in each drawing will be enlarged or reduced as appropriate for ease of understanding. Furthermore, some members that are not important for explaining the embodiments will be omitted from the drawings.

[0017] [First Embodiment] The ship control device 10 according to the first embodiment of this disclosure will be described below with reference to Figures 1 to 6. Figure 1 is a schematic diagram showing a ship 1 to which the ship control device 10 according to the first embodiment is applied.

[0018] The vessel 1 comprises a hull 90, an information detection means 88, a navigation instruction unit 50, a main engine 74, and a steering gear 76. The ship control device 10 is installed on the vessel 1. The main engine 74 is an engine that propels the vessel 1, rotating a propeller 75 to impart thrust to the hull 90. The main engine 74 can be any engine capable of propelling the hull 90, and in this example, it is a diesel engine. The main engine 74 consumes an amount of fuel corresponding to its rotational speed and torque in order to operate it. The main engine 74 may be provided with a governor (not shown) that finely adjusts the amount of fuel supplied to suppress fluctuations in rotational speed in response to load fluctuations of the main engine 74.

[0019] The steering gear 76 is a power steering mechanism that rotates the rudder 77, which is mounted on the hull of the ship 1, in order to turn the ship 1. The steering gear 76 changes the rudder angle using power from a power source such as an electric motor.

[0020] The information detection means 88 detects information about the current status of the vessel 1 and outputs it to the vessel control device 10. Details of the information about the current status of the vessel 1 will be described later.

[0021] The navigation instruction unit 50 outputs navigation instructions for the vessel 1 to the ship control device 10 based on the navigation plan. For example, the navigation instruction unit 50 generates the target route and target ground speed for the vessel 1 as navigation instructions and outputs them to the ship control device 10. As navigation instructions, the target arrival time may be used instead of, or in addition to, the target ground speed.

[0022] The following describes the overview of the ship control device 10. The ship control device 10 stores multiple hull models. Based on the current status of the ship 1, the ship control device 10 sets one hull model (hereinafter referred to as the "set hull model") from among the multiple hull models. Based on the navigation instructions received from the navigation instruction unit 50 and the set hull model, the ship control device 10 predicts what commands should be given to the set hull model to perform actions in accordance with the navigation instructions, and generates appropriate control command values. The ship control device 10 outputs control signals based on the generated control command values ​​to the main engine 74 and the steering gear 76.

[0023] Thus, the vessel 1 operates automatically in accordance with navigation instructions based on the navigation plan. The vessel 1 may be an autonomous vessel that does not require steering by a pilot, or it may be a conventional vessel that requires steering by a pilot. If the vessel 1 is a conventional vessel, it is further equipped with a steering device (not shown) that accepts steering input from the pilot and outputs control signals to the main engine 74 and the steering gear 76. If the vessel 1 is a conventional vessel, it may be possible to switch between control by the ship control device 10 and control by the steering device. The details of the ship control device 10 will be described below.

[0024] Figure 2 is a schematic block diagram of the ship control device 10. Each block shown in Figure 2 can be realized in hardware terms using electronic elements, electronic circuits, and mechanical parts, such as a computer processor, CPU, and memory, and in software terms using computer programs, etc. However, here we depict the functional blocks realized through the coordination of these elements. Therefore, it will be understood by those skilled in the art that these functional blocks can be realized in various ways through combinations of hardware and software.

[0025] The ship control device 10 comprises a reception unit 12, a storage unit 14, an acquisition unit 16, a setting unit 18, a generation unit 20, and an output unit 22.

[0026] The reception unit 12 receives navigation instructions from the navigation instruction unit 50. The memory unit 14 stores multiple hull models. A hull model is a motion model used to predict the future hull behavior of ship 1 through simulation. A hull model may be a mathematical model based on physical formulas, or a learning model generated by machine learning such as deep learning. Multiple hull models are prepared for each navigation situation. Navigation situations include, for example, voyages in the open ocean or along the coast, and harbor navigations within harbors. Harbor navigation can be classified into berthing, approach, and docking. Since the assumed ship speed over land, water temperature, waves, currents, wind speed, water depth, etc. differ for each navigation situation, the hull motion characteristics will also differ. For example, the higher the ship speed over the ground, the more susceptible the ship 1 is to the effects of waves, and the lower the ship speed over the ground, the less the rotational speed of the main engine 74 and the rudder angle of the rudder 77 are reflected in its motion. Therefore, the ship control device 10 can set an appropriate ship model according to the current navigation situation of the ship 1 by preparing multiple ship models for each navigation situation. In this embodiment, the memory unit 14 stores a first ship model 60A corresponding to navigation outside the harbor, a second ship model 60B corresponding to approach, and a third ship model 60C corresponding to docking.

[0027] The acquisition unit 16 acquires information on the current status of the vessel 1 from the information detection means 88. The current status of the vessel 1 includes information on at least one of the vessel 1's current speed relative to the ground and its position. The current status of the vessel 1 may further include information on at least one of the following: the load being carried, water temperature, wave conditions, currents, wind, and water depth.

[0028] Here, we will describe in detail the information detection means 88 that detects information about the current status of the vessel 1. In this embodiment, the information detection means 88 includes a GPS receiver 41, a gyro sensor 42, a current sensor 43, a wind direction and speed sensor 44, a water depth sensor 45, a wave height sensor 46, a water temperature sensor 47, a load sensor 48, a main engine sensor 78, and a rudder angle sensor 79.

[0029] The GPS receiver 41 calculates the current position of the ship 1 using satellite radio waves and outputs the calculated current position to the ship control device 10. The GPS receiver 41 can be any device capable of calculating its own current position using satellite radio waves and is not limited to a specific system. The GPS receiver 41 in this embodiment is a Global Positioning System that receives positioning signals from several satellites in orbit and calculates the receiver's current position.

[0030] The gyro sensor 42 acquires the attitude of the vessel 1 and determines the actual bow direction of the vessel 1 from the acquired attitude. The gyro sensor 42 outputs the determined actual bow direction to the ship control device 10. The tidal current sensor 43 is a device capable of measuring the tidal current affecting the vessel 1 and outputs the measured tidal current to the ship control device 10. The wind direction and wind speed sensor 44 is a device capable of measuring the wind direction and wind speed affecting the vessel 1 and outputs the measured wind direction and wind speed to the ship control device 10.

[0031] The water depth sensor 45 is a device capable of measuring the water depth affecting the ship 1 and outputs the measured water depth to the ship control device 10. The wave height sensor 46 is a device capable of measuring the wave height affecting the ship 1 and outputs the measured wave height to the ship control device 10. The water temperature sensor 47 is a device capable of measuring the water temperature affecting the ship 1 and outputs the measured water temperature to the ship control device 10. The load sensor 48 is a device capable of measuring the load of the cargo loaded on the ship 1 (hereinafter referred to as "loaded load") and outputs the measured loaded load to the ship control device 10. The information detection means 88 may, instead of the load sensor 48, hold information on the loaded load that has been set in advance before departure and output the loaded load to the ship control device 10.

[0032] The main engine sensor 78 acquires the actual rotational speed and shaft horsepower of the main engine 74, and outputs the acquired rotational speed and shaft horsepower to the ship control device 10. The shaft horsepower of the main engine 74 can be measured by a shaft horsepower meter installed on the propeller shaft. The rudder angle sensor 79 acquires the actual rudder angle of the rudder 77 from the steering gear 76, and outputs the acquired actual rudder angle to the ship control device 10.

[0033] The setting unit 18 sets a target hull model from a plurality of hull models based on the current status of the vessel 1 acquired by the acquisition unit 16. In this embodiment, the setting unit 18 sets the target hull model based on at least one of the information of the vessel 1's current speed over the ground and its position. The vessel 1's current speed over the ground can be calculated from the change over time of the vessel 1's current position input from the GPS receiver 41. This allows the ship control device 10 to set a suitable hull model based on the information that the vessel 1 normally acquires.

[0034] Figure 3 shows an example of how the setting unit 18 sets the hull model. The horizontal axis in Figure 3 shows the distance of the vessel 1 from the port or pier where it is anchored, with the right side indicating a shorter distance from the port or pier. This distance is obtained from the current position information of the vessel 1. The vertical axis in Figure 3 shows the current speed of the vessel 1 over the ground, with the upper side indicating a higher speed. Figure 3 shows the transition of the vessel 1's navigation phase from out-of-harbor navigation to approach, and then to docking. Comparing the out-of-harbor navigation, approach, and docking phases, the distance from the port or pier decreases in the order of out-of-harbor navigation, approach, and docking. Also, the speed over the ground usually decreases in the order of out-of-harbor navigation, approach, and docking. Therefore, the setting unit 18 can set the hull model by switching between a first hull model 60A corresponding to out-of-harbor navigation, a second hull model 60B corresponding to approach, and a third hull model 60C corresponding to docking, based on at least one piece of information regarding the current speed and position of the vessel 1. The setting unit 18 may set the hull model based on one piece of information regarding the current speed and position of the vessel 1, while using the other piece of information as a supplement. For example, even if the setting unit 18 should switch the hull model from the first hull model 60A to the second hull model 60B based on the current position of the vessel 1, if the speed of the vessel 1 is too high to use the second hull model 60B, it may keep the first hull model 60A and delay the switching timing.

[0035] The setting unit 18 may set the hull model based on at least one of the following pieces of information (hereinafter referred to as "additional information"): the load on the vessel, water temperature, waves, currents, wind, and water depth. For example, the load on the vessel affects the draft of vessel 1. In the example shown in Figure 3, the setting unit 18 may adjust the timing of switching the hull model based on the additional information. This allows the ship control device 10 to set a more appropriate hull model using additional information such as the external environment of vessel 1. The setting unit 18 may also set the hull model for each specific destination. This allows the ship control device 10 to use a hull model that has been pre-optimized based on the geographical and meteorological conditions expected for the destination, thus enabling it to set a more appropriate hull model.

[0036] Returning to Figure 2, the generation unit 20 generates control command values ​​based on the navigation instructions received by the reception unit 12 and the hull model set by the setting unit 18. For example, if the hull model is a learning model, the generation unit 20 gives thousands of commands to the hull model and, based on the simulation results, selects and outputs the control command value that is closest to the target value based on the navigation instructions. The control command values ​​include the rotational speed of the main engine 74 and the rudder angle of the steering gear 76. In this case, the generation unit 20 functions as an optimizer that outputs the optimal control command value.

[0037] The output unit 22 outputs control signals based on the control command values ​​generated by the generation unit 20 to the main engine 74 and the steering gear 76. The destinations of the control signals may differ depending on the set hull model. For example, if the set hull model is the first hull model 60A or the second hull model 60B, the control signals may be output only to the main engine 74 and the steering gear 76, and if the set hull model is the third hull model 60C, the control signals may be output to the main engine 74 and the steering gear 76 as well as thrusters (not shown) and fin stabilizers (not shown).

[0038] Figure 4 is a flowchart illustrating an example of the operation of the ship control device 10. The ship control device 10 receives navigation instructions from the ship 1 via the reception unit 12 (S10). The timing at which the ship control device 10 receives navigation instructions can be any point before the ship control device 10 begins controlling the ship 1.

[0039] The ship control device 10 acquires the current status of the ship 1 via the acquisition unit 16 (S12). Based on the acquired current status of the ship 1, the ship control device 10 sets a designated hull model from a plurality of hull models stored in the memory unit 14 using the setting unit 18 (S14). Based on the navigation instruction received via the reception unit 12 and the designated hull model set using the setting unit 18, the ship control device 10 generates a control command value using the generation unit 20 (S16).

[0040] The ship control device 10 outputs a control signal via the output unit 22 based on the control command value generated by the generation unit 20 (S18). Based on the output control signal, the main engine 74 and the steering gear 76, etc., are driven. If the ship control device 10 has not met the conditions for ending control by the ship control device 10 (N in S20), it returns to step S12. If the ship control device 10 has met the conditions for ending control by the ship control device 10 (Y in S20), it terminates its operation. The conditions for ending control by the ship control device 10 may be, for example, that the ship 1 has arrived at its destination, or that an instruction to terminate control by the ship control device 10 has been input from an external source.

[0041] Returning to Figure 2, the ship control device 10 may further include an update unit 26, a prediction unit 28, and a notification unit 30. The prediction unit 28 generates control predictions based on a set hull model. The control prediction is information that can be compared with the control result when the ship 1 is controlled by a control signal based on control command values ​​generated based on the set hull model. For example, the control prediction is a predicted value of the ship's position and ground speed obtained from a simulation using the set hull model, and the control result is the measured value of the ship 1's position and ground speed when the ship 1 is actually controlled by the control signal.

[0042] The update unit 26 updates the set hull model based on the control results obtained when the ship 1 is controlled based on the control signal. In this embodiment, the update unit 26 compares the control result with the control prediction, and if the control result differs from the control prediction, it updates the set hull model so that the control result approaches the control prediction. The update unit 26 may store the updated set hull model in place of the corresponding hull model in the storage unit 14. This allows the ship control device 10 to reflect changes in the hull motion characteristics due to fouling or deterioration of the ship 1 in the set hull model using the control results obtained when the ship 1 is actually controlled by the control signal using the set hull model, thereby further improving the accuracy of the set hull model.

[0043] If the configured hull model is a learning model, the learning model may be retrained using the control result information as training data. The update unit 26 may then update the configured hull model to the retrained configuration model at a predetermined timing. The control result information of the ship 1 used by the update unit 26 to update the configured hull model may differ depending on the configured hull model. For example, if the configured hull model is the first hull model 60A or the second hull model 60B, the information from the 6-axis sensor may not be used, while if the configured hull model is the third hull model 60C, the information from the 6-axis sensor may be used.

[0044] The notification unit 30 notifies the user if the number of times the set hull model has been updated by the update unit 26 exceeds a predetermined number within a predetermined period. For example, if the update unit 26 updates the set hull model and repeatedly increases the command value for the rotational speed of the main engine 74, but the ship's speed over the ground does not rise to the control prediction level, it is considered that the set hull model deviates from the control result, and as long as the set hull model is used as a reference, the control result cannot be accurately predicted even after updating. The ship control device 10 can inform the user that the update frequency of the set hull model is too high, so the user can determine, for example, that the set hull model itself is inappropriate.

[0045] Figure 5 is a flowchart showing another example of the operation of the ship control device 10. The ship control device 10 performs steps S10 to S18, similar to Figure 4. Then, the ship control device 10 acquires the control result of the ship 1 being actually controlled via the acquisition unit 16 (S30). The ship control device 10 compares the acquired control result with the control prediction from the prediction unit 28 to determine whether the value of the control result differs from the value of the control prediction (S32). If the value of the control result differs from the value of the control prediction (Y in S32), the ship control device 10 updates the set hull model using the update unit 26 (S34). If the value of the control result does not differ from the value of the control prediction (N in S32), the ship control device 10 proceeds to step S36. Note that the ship control device 10 may determine that the value of the control result does not differ from the value of the control prediction if the error between the value of the control result and the value of the control prediction is within a certain range.

[0046] The ship control device 10 issues a notification using the notification unit 30 (S38) when the update frequency of the set hull model exceeds a certain level, that is, when the number of times the set hull model has been updated by the update unit 26 within a predetermined period exceeds a predetermined number. If the update frequency of the set hull model is below a certain level (N in S36), the ship control device 10 proceeds to step S20. Step S20 is the same as in Figure 4.

[0047] Returning to Figure 2, the notification unit 30 may notify if the difference between the control prediction and the control result of the ship 1 based on the control signal exceeds a predetermined allowable error range. This allows the ship control device 10 to inform the user that the difference between the prediction based on the set hull model and the actual control result of the ship 1 exceeds the allowable error range, so the user can determine, for example, that the set hull model itself is not appropriate.

[0048] Figure 6 is a flowchart showing yet another example of the operation of the ship control device 10. The ship control device 10 performs steps S10 to S18, similar to Figure 4. Then, the ship control device 10 acquires the control result of the ship 1 being actually controlled via the acquisition unit 16 (S40). The ship control device 10 compares the acquired control result with the control prediction from the prediction unit 28 and determines whether the difference between the control prediction value and the control result value exceeds the allowable error (S42). If the difference between the control prediction value and the control result value exceeds the allowable error (Y in S42), the ship control device 10 makes a notification using the notification unit 30 (S44). If the difference between the control prediction value and the control result value is less than the allowable error (N in S42), the process proceeds to step S20. Step S20 is the same as in Figure 4.

[0049] The ship control device 10 may perform the operations shown in Figure 5 and Figure 6 in parallel. In this case, the allowable error used in the determination in step S42 is larger than the error used in the determination in step S32. As a result, the ship control device 10 updates the set hull model when the error between the control prediction and the control result is relatively small, and issues a notification when the error is relatively large, as updating the set hull model is likely to be insufficient to address the issue.

[0050] Returning to Figure 2, the ship control device 10 may further include a stop unit 32 that stops the output of the control signal by the output unit 22 when the values ​​related to the environmental information of the ship 1 are above a predetermined stop threshold. Here, the values ​​related to the environmental information of the ship 1 are, for example, values ​​related to wind speed, current, wave information, etc. The stop threshold is the value at the boundary between an environment suitable for prediction using the hull model and an environment that is not suitable. As a result, the ship control device 10 does not output a control signal when it is difficult to make a prediction using the hull model, thus reducing the possibility of performing inappropriate ship control. When the output of the control signal is stopped by the stop unit, the ship control device 10 may switch from control by the ship control device 10 to control by the steering device if the ship 1 is a normally operating ship, or if the ship 1 is an autonomous ship, it may switch to control that maintains the attitude of the ship 1 using a DPS (Dynamic Positioning System), etc.

[0051] The ship control device 10 may use the prediction unit 28 to generate control predictions for hull models other than the set hull model set using the setting unit 18, from among the multiple hull models stored in the memory unit 14. The ship control device 10 may use the notification unit 30 to notify the user or prevent the hull model from being set by the setting unit 18 if the difference between the control prediction for a hull model other than the set hull model and the actual control result of controlling the ship 1 with a control signal based on the set hull model exceeds a predetermined error range. The multiple hull models stored in the memory unit 14 are each suitable for different navigation conditions, but since they are models for reproducing the hull motion characteristics of the same ship 1, it is expected that the difference between the control prediction and the control result will be within a certain range. Therefore, if the difference between the control prediction and the control result exceeds this range, the hull model is considered unsuitable for predicting the hull motion of the ship 1, and the above processing becomes effective.

[0052] As described above, the ship control device 10 of this embodiment includes a reception unit 12 for receiving navigation instructions, a storage unit 14 for storing multiple hull models, a setting unit 18 for setting a target hull model from the multiple hull models based on the current status of the ship 1, a generation unit 20 for generating control command values ​​for the ship 1 based on the navigation instructions and the target hull model, and an output unit 22 for outputting control signals based on the control command values. As a result, the ship control device 10 can set an appropriate hull model considering the hull motion characteristics that change according to the current status of the ship 1, and generate control command values ​​using the set hull model. Therefore, the ship control device 10 can make highly accurate predictions of hull motion considering the hull motion characteristics that change according to the current status of the ship 1, and thus can perform appropriate ship control.

[0053] In the ship control device 10 of this embodiment, multiple hull models may be prepared for each navigation situation. This allows the ship control device 10 to set an appropriate hull model according to the current navigation situation of the ship 1.

[0054] In the ship control device 10 of this embodiment, the setting unit 18 may set the hull model based on at least one of the ship's current speed and position relative to the ground. This allows the ship control device 10 to set a suitable hull model based on information that the ship 1 normally acquires.

[0055] In the ship control device 10 of this embodiment, the setting unit may set the hull model based on at least one of the following pieces of information: the load on the ship, water temperature, waves, currents, wind, and water depth. This allows the ship control device 10 to set a more appropriate hull model using information such as the external environment of the ship 1.

[0056] The ship control device 10 of this embodiment may further include an update unit 26 that updates the set hull model based on the control results of the ship 1 based on the control signal. This allows the ship control device 10 to reflect changes in the ship 1 due to fouling, deterioration, etc., in the set hull model using the control results of the ship 1 actually controlled by the control signal using the set hull model, thereby further improving the prediction accuracy of the set hull model.

[0057] The ship control device 10 of this embodiment may further include a notification unit that notifies the user when the number of times the set hull model has been updated by the update unit exceeds a predetermined number within a predetermined period. This allows the ship control device 10 to inform the user that the update frequency of the set hull model is too high, so that the user can determine, for example, that the set hull model itself is not appropriate.

[0058] The ship control device 10 of this embodiment may further include a prediction unit that outputs a navigation instruction and a ship control prediction based on a set hull model, and a notification unit that notifies the user when the difference between the control prediction and the control result of the ship 1 based on the control signal exceeds a predetermined allowable error range. This allows the ship control device 10 to inform the user that the difference between the prediction based on the set hull model and the actual control result of the ship 1 exceeds an allowable error range, so that the user can determine, for example, that the set hull model itself is not appropriate.

[0059] The ship control device 10 of this embodiment may further include a stop unit 32 that stops outputting the control signal from the output unit 22 when the value related to the environmental information of the ship 1 is equal to or greater than a predetermined stop threshold. As a result, the ship control device 10 does not output a control signal when it is difficult to predict the situation using the hull model, thereby reducing the possibility of performing inappropriate ship control.

[0060] [Second Embodiment] The ship control system 3 according to the second embodiment of this disclosure will be described below with reference to Figures 7 and 8. Figure 7 is a schematic diagram showing a ship 1 to which the ship control system 3 according to the second embodiment is applied.

[0061] Since the vessel 1 is the same as in the first embodiment, its description will be omitted. The vessel control system 3 includes a vessel control device 10A and a vessel control support device 5. The vessel control device 10A is installed on the vessel 1. The vessel control support device 5 is installed in a location other than the vessel 1, for example, on land or on another vessel. The vessel control device 10A and the vessel control support device 5 are able to communicate with each other.

[0062] The ship control device 10A, like the ship control device 10 of the first embodiment (see Figure 2), includes a receiving unit 12, an acquisition unit 16, and an output unit 22. The ship control device 10A further includes a communication unit (not shown) for mutual transmission and reception of data with the ship control support device 5. The ship control device 10A transmits the navigation instructions from the navigation instruction unit 50 received via the receiving unit 12 and the information on the current status of the ship 1 acquired from the information detection means 88 via the acquisition unit 16 to the ship control support device 5 via the communication unit. The ship control device 10A also outputs the control signals received from the ship control support device 5 via the communication unit to the main engine 74 and the steering gear 76 via the output unit 22.

[0063] Figure 8 is a schematic block diagram of the ship control system 3. In Figure 8, the configuration of the ship control device 10A is not shown. The ship control support device 5 comprises a communication unit 34, a storage unit 14, a setting unit 18, a generation unit 20, and an output unit 22A. The storage unit 14, the setting unit 18, and the generation unit 20 are the same as in the first embodiment, so their descriptions are omitted.

[0064] The communication unit 34 receives navigation instructions and information on the current status of the ship 1 from the ship control device 10A. The output unit 22A transmits control signals based on the control command values ​​generated by the generation unit 20 to the ship control device 10A via the communication unit 34. The ship control device 10A outputs the control signals received from the ship control support device 5 to the main engine 74 and the steering gear 76. Similar to the first embodiment, the output destination of the control signals may differ depending on the set hull model.

[0065] The ship control support device 5 may further include an update unit 26, a prediction unit 28, a notification unit 30, and a stop unit 32. The update unit 26, prediction unit 28, notification unit 30, and stop unit 32 are the same as in the first embodiment, so their description is omitted.

[0066] The ship control support device 5 of this embodiment includes a communication unit 34 that can communicate with the ship control device 10A installed on the ship 1, a storage unit 14 that stores multiple hull models, a setting unit 18 that sets a target hull model from the multiple hull models based on the current status of the ship 1, a generation unit 20 that generates control command values ​​based on navigation instructions and the target hull model, and an output unit 22 that outputs control signals based on the control command values ​​to the ship control device 10A. As a result, the ship control support device 5 can set an appropriate hull model considering the hull motion characteristics that change according to the current status of the ship 1, and generate control command values ​​using the set hull model. Therefore, the ship control support device 5 can make highly accurate predictions of hull motion considering the hull motion characteristics that change according to the current status of the ship 1, and thus can perform appropriate ship control.

[0067] Although the configuration of the ship control support device 5 in this embodiment is the same as in the first embodiment, a description of this configuration has been omitted, but the same effects as in the first embodiment can be obtained.

[0068] [Third Embodiment] The ship control device 110 according to the third embodiment of this disclosure will be described below with reference to Figures 9 to 11. The ship control device 110 is applicable to ship 1 (see Figure 1), similar to the ship control device 10 according to the first embodiment. Since ship 1 is the same as in the first embodiment, its description will be omitted.

[0069] Figure 9 is a schematic block diagram of the ship control device 110. The ship control device 110 comprises a receiving unit 12, a storage unit 114, an acquisition unit 16, a setting unit 118, a generation unit 120, and an output unit 22. The receiving unit 12, the acquisition unit 16, and the output unit 22 are the same as in the first embodiment, so their description is omitted.

[0070] The memory unit 114 stores the hull model 160. The hull model 160 is a motion model used to predict the future hull behavior of the ship 1 through simulation, similar to the hull model described in the first embodiment. The hull model 160 in this embodiment is used in particular for model predictive control.

[0071] Here, the model predictive control in this embodiment will be described. In model predictive control, the ship control device 110 predicts the motion of the ship 1 when the ship 1 is controlled by a control pattern based on the hull model 160, and determines the optimal control pattern based on that prediction. The control pattern is, for example, a combination of control command values ​​for controlling the propeller thrust of the main engine 74, engine speed, rudder angle of the steering gear 76, thrust of the thruster (not shown), etc. In order to determine the optimal control pattern, the ship control device 110 determines the control pattern such that the evaluation function is minimized.

[0072] As explained in the first embodiment, the hull motion characteristics of the vessel 1 differ depending on the navigation conditions. For example, when the vessel 1 is at low speed, it is susceptible to disturbances (wind, waves, currents, etc.). Therefore, it is conceivable to increase the weight coefficient of the term related to the error from the planned route (hereinafter referred to as "route error") among the penalty terms of the evaluation function. In particular, when the vessel 1 is docking or undocking, or navigating within a bay, the distance to the quay and other vessels is small, and it is required that the route error be reduced even further. However, when the vessel 1 is sailing in the open ocean, the distance to the quay and other vessels is large, so a certain degree of route error is acceptable, and adhering to the navigation plan becomes more important than the route error. Therefore, in this case, the weight coefficient of the term related to route error should be reduced. In light of these circumstances, this embodiment is characterized by adjusting the weight coefficient of each penalty term of the evaluation function according to the navigation conditions in order to improve the accuracy of model predictive control.

[0073] Returning to the explanation of the memory unit 114, the memory unit 114 further stores weight information 162 of the evaluation function. The weight information 162 is information for adjusting the weight coefficients of each penalty term of the evaluation function for each navigation situation. The weight information 162 may, for example, be information that associates the weight coefficients of each penalty term for each navigation situation, or it may be information that shows how much the weight coefficients of each penalty term are adjusted from a predetermined reference value for each navigation situation. Based on the weight information 162, different evaluation functions can be generated for each navigation situation, and each generated evaluation function can be applied to the hull model 160. In this way, by applying different evaluation functions to a single hull model 160, multiple hull models corresponding to different navigation situations can be obtained. In other words, the memory unit 114 can also store multiple hull models and store the weight information of the evaluation function corresponding to each of the multiple hull models. The memory unit 114 may also store multiple hull models to which different evaluation functions have been applied in advance for each navigation situation. In this case, the memory unit 114 does not necessarily have to store the weight information 162.

[0074] The setting unit 118 sets a set hull model from a plurality of hull models based on the current situation of the ship 1 acquired by the acquisition unit 16, similar to the setting unit 18 in the first embodiment. The setting unit 118 in this embodiment sets the weight coefficients of each term of the evaluation function based on the weight information 162 corresponding to the set hull model. The evaluation function with the weight coefficients of each term set in this way is also referred to as a set evaluation function.

[0075] The evaluation function includes at least one of the surge ship speed error, sway ship speed error, yaw angular velocity error, course error, and heading error as a penalty term. For example, the evaluation function f(x ,

[0076] , vsu , h , t , h , vy , vy , vsw , , t , t , t , t ) can be expressed by the following mathematical formula. f(x t )=c vsu f vsu (x t )+c vsw f vsw (x t )+c vy f vy (x t )+c t f t (x t )+c h f h (x t )+····· Here, f vsu (x t ) represents the surge ship speed error, f<00000​​​​​​​​​​​​​​​​​​​​​​​​​​​The generation unit 120 generates control command values ​​based on the navigation instructions received by the reception unit 12 and the set hull model set by the setting unit 118, similar to the generation unit 20 of the first embodiment. In this embodiment, the generation unit 120 generates control command values ​​by model predictive control that minimizes the set evaluation function.

[0077] Figure 10 shows an example of a penalty term corresponding to a weighting coefficient adjusted for each navigation situation. In Figure 10, the hull model number is indicated for each hull model to which the evaluation function with adjusted weighting coefficients is applied.

[0078] When the navigation situation of vessel 1 is an approach, the weighting coefficient terms to be adjusted are the surge speed error term and the route error term. This is because, in an approach situation, the priority should be on safely transitioning to docking and undocking, and therefore the surge speed must be sufficiently reduced.

[0079] When the navigation situation of vessel 1 is docking or undocking, the weight coefficient terms to be adjusted are the surge speed error, sway speed error, yaw angular velocity error, and heading error. This is because, in such situations, the priority should be to avoid collision with the quay.

[0080] When the navigation situation of vessel 1 is one of avoiding another vessel, the weighting coefficient terms to be adjusted are the term for the route error and the term for the surge speed error. This is because, in a situation of avoiding another vessel, avoiding a collision with the other vessel should be the top priority, and the route and the timing of navigation (ship speed) become important.

[0081] When Vessel 1 is sailing in the open ocean, the weighting coefficients to be adjusted are the surge speed error and the heading error. This is because adherence to the sailing plan should be the top priority in open ocean voyages.

[0082] Figure 11 is a flowchart illustrating an example of the operation of the ship control device 110. The ship control device 110 receives navigation instructions from the ship 1 via the reception unit 12 (S60). The timing at which the ship control device 110 receives navigation instructions can be any point before the ship control device 110 begins controlling the ship 1.

[0083] The ship control device 110 acquires the current status of the ship 1 via the acquisition unit 16 (S62). Based on the acquired current status of the ship 1, the ship control device 110 sets a set hull model from a plurality of hull models stored in the memory unit 114 using the setting unit 118 (S64). Based on the weight information 162 corresponding to the set hull model, the ship control device 110 sets the weight coefficients of each term of the evaluation function using the setting unit 118 (S66). The evaluation function with the weight coefficients of each term set is the set evaluation function. Based on the navigation instruction received via the reception unit 12 and the set hull model set using the setting unit 118, the ship control device 110 generates a control command value using the generation unit 20 by model predictive control that minimizes the set evaluation function (S68).

[0084] The ship control device 110 outputs a control signal via the output unit 22 based on the control command value generated by the generation unit 120 (S70). Based on the output control signal, the main engine 74 and the steering gear 76, etc., are driven. If the ship control device 110 has not met the termination conditions for control by the ship control device 110 (N in S72), it returns to step S62. If the ship control device 110 has met the termination conditions for control by the ship control device 110 (Y in S72), it terminates its operation. The termination conditions for control by the ship control device 110 may be, for example, that the ship 1 has arrived at its destination, or that an instruction to terminate control by the ship control device 110 has been input from an external source.

[0085] Returning to Figure 9, the ship control device 110 may further include an update unit 26, a prediction unit 28, a notification unit 30, and a stop unit 32. The update unit 26, prediction unit 28, notification unit 30, and stop unit 32 are the same as in the first embodiment, so their description is omitted.

[0086] The ship control device 110 can also be applied to a system similar to the ship control system 3 according to the second embodiment. That is, the ship control system 3 according to the second embodiment may be a ship control system equipped with a ship control support device in which the storage unit 14, setting unit 18, and generation unit 20 in the ship control support device 5 are replaced with a storage unit 114, a setting unit 118, and a generation unit 120, respectively. The other configurations of this ship control system are the same as those of the ship control system 3, so their description will be omitted.

[0087] As described above, the ship control device 110 of this embodiment includes a reception unit 12 for receiving navigation instructions, a storage unit 114 for storing a plurality of hull models, a setting unit 118 for setting a set hull model from the plurality of hull models based on the current status of the ship 1, a generation unit 120 for generating control command values ​​for the ship 1 based on the navigation instructions and the set hull model, and an output unit 22 for outputting control signals based on the control command values. The storage unit 114 stores weight information 162 of the evaluation function of model predictive control corresponding to each of the plurality of hull models, the setting unit 118 sets the weight coefficients of each term of the evaluation function based on the weight information 162 corresponding to the set hull model to form a set evaluation function, and the generation unit 120 generates control command values ​​by model predictive control that minimizes the set evaluation function. As a result, in addition to the same effects as in the first embodiment, the ship control device 110 can improve the accuracy of predicting hull motion by model predictive control by adjusting the weight coefficients of each term of the evaluation function according to the current navigation status of the ship 1.

[0088] The embodiments of the present invention have been described in detail above. The embodiments described above are merely examples of how to implement the present invention. The contents of the embodiments do not limit the technical scope of the present invention, and many design changes, such as changes, additions, and deletions of components, are possible as long as they do not depart from the spirit of the invention as defined in the claims. In the embodiments described above, such design changes are described with notations such as "of the embodiments" or "in the embodiments," but design changes may also be permitted in contents without such notations.

[0089] In each embodiment, the current status of the vessel 1 is determined based on the information acquired by the acquisition unit 16. However, the current status of the vessel 1 may also be determined based on navigation instructions received by the reception unit 12. Since the content of the navigation instructions is determined based on the information acquired by the acquisition unit 16, this is equivalent to determining the current status of the vessel 1 using the information acquired by the acquisition unit 16.

[0090] In each embodiment, the content of the control command values ​​generated by the generation unit 20 and output by the output unit 22 may be determined according to the systems installed on the ship 1. For example, if the ship 1 is a ship with an electric propulsion mechanism such as a hybrid propulsion ship, the rotation speed of the main propeller drive motor is output as the control command value. If the ship 1 is equipped with a wind power propulsion system, control parameters such as the rotation direction of the wind power propulsion system and the direction of the sails are output as control command values.

[0091] Any combination of the embodiments and modifications described above is also useful as an embodiment of the present invention. The new embodiments resulting from these combinations possess the combined effects of the respective embodiments and modifications.

[0092] In the embodiments disclosed herein, those in which multiple functions are provided in a distributed manner may have some or all of those multiple functions integrated into a single unit, and conversely, those in which multiple functions are integrated may have some or all of those functions provided in a distributed manner. Whether the functions are integrated or distributed, the configuration should be such that the objective of the invention can be achieved. [Explanation of symbols]

[0093] 1...Ship, 3...Ship control system, 5...Ship control support device, 10,110...Ship control device, 12...Reception unit, 14,114...Storage unit, 16...Acquisition unit, 18,118...Setting unit, 20,120...Generation unit, 22...Output unit, 26...Update unit, 28...Prediction unit, 30...Notification unit, 32...Stop unit, 34...Communication unit, 90...Hull.

Claims

1. The reception area for receiving navigation instructions, A memory unit that stores multiple hull models, A setting unit that sets a target hull model from the multiple hull models based on the current status of the vessel, A generation unit that generates control command values ​​for the ship based on the navigation instructions and the set hull model, An output unit that outputs a control signal based on the control command value, A ship's control system equipped with the following features.

2. The ship control device according to claim 1, wherein the plurality of hull models are prepared for each navigation situation.

3. The ship control device according to claim 1, wherein the setting unit sets the set hull model based on information of at least one of the ship's current speed over land and position.

4. The ship control device according to claim 3, wherein the setting unit sets the set hull model based on at least one of the following: load weight, water temperature, waves, currents, wind, and water depth.

5. The ship control device according to claim 1, further comprising an update unit that updates the set hull model based on the control result of the ship based on the control signal.

6. The ship control device according to claim 5, further comprising a notification unit that notifies when the number of times the set hull model has been updated by the update unit exceeds a predetermined number of times within a predetermined period.

7. A prediction unit that outputs the navigation instructions and the ship control prediction based on the set hull model, A notification unit that notifies when the difference between the control prediction and the control result of the ship based on the control signal exceeds a predetermined tolerance range, The ship control device according to claim 1, further comprising:

8. The ship control device according to claim 1, further comprising a stop unit that stops the output of the control signal by the output unit when the value relating to the environmental information of the ship is equal to or greater than a predetermined stop threshold.

9. The memory unit stores weight information of the evaluation function of the model predictive control corresponding to each of the plurality of hull models. The setting unit sets the weight coefficients of each term of the evaluation function based on the weight information corresponding to the set hull model to form a set evaluation function. The generation unit generates the control command value by model predictive control that minimizes the set evaluation function. The ship control device according to claim 1.

10. The ship control device according to claim 9, wherein the evaluation function includes at least one of surge speed error, sway speed error, yaw angular velocity error, route error, and heading error as a penalty term.

11. A communication unit that can communicate with a ship control system installed on a ship, A memory unit that stores multiple hull models, A setting unit that sets a target hull model from the multiple hull models based on the current status of the vessel, A generation unit that generates control command values ​​based on navigation instructions and the set hull model, An output unit that outputs a control signal based on the control command value to the ship's control device, A ship control support system equipped with the following features.

12. A method for controlling a ship control device installed on a ship, or a ship control support device capable of communicating with the ship control device, Steps to receive navigation instructions, Based on the current status of the vessel, the step of selecting a target hull model from multiple hull models, The steps include generating ship control command values ​​based on the navigation instructions and the set hull model, The steps include: outputting a control signal based on the control command value; A ship control method including

13. A program for controlling a ship control device installed on a ship, or a ship control support device that can communicate with the said ship control device, wherein the computer... Steps to receive navigation instructions, Based on the current status of the vessel, the step of selecting a target hull model from multiple hull models, The steps include generating ship control command values ​​based on the navigation instructions and the set hull model, The steps include: outputting a control signal based on the control command value; A ship control program to execute this.

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