Systems for controlling ships and ships

Abstract

In position-holding control using automated ship navigation, the aim is to easily maintain the ship at the target location and improve the accuracy of position-holding control. [Solution] The ship steering system 100 includes a ship propulsion unit 3 and a ship steering controller 30. The ship propulsion unit 3 and the ship steering controller 30 perform position holding control to control the ship propulsion unit 3 to keep the ship 10 at a target location. The position holding control includes a first turn control that controls the output of the ship propulsion unit 3 and the rotation direction of the propeller 14 based on information about the target location of the ship 10 and the position information of the ship 103, and controls the steering angle within a predetermined angular range, and a second turn control that controls the rotation direction of the propeller 14 based on information about the target location of the ship 10 and the position information of the ship 10, and controls the steering angle to a first angle that is greater than the maximum steering angle within a predetermined angular range.

Description

Technical Field

[0001] The present invention relates to a system for controlling a ship and a ship.

Background Art

[0002] As control for automatic ship steering, position-keeping control for keeping a ship at a target point is known. In position-keeping control, when the ship deviates from the target point, the ship is turned around so that the stern or bow of the ship faces the target point, and then the ship is moved in the fore-and-aft direction to keep the ship at the target point.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] In conventional position-keeping control, the magnitude of the thrust generated by a ship propeller is controlled according to the amount of displacement of the ship in the fore-and-aft direction with respect to the target point. For this reason, for example, when the amount of displacement of the ship in the fore-and-aft direction with respect to the target point is small, the magnitude of the thrust generated by the ship propeller becomes small, so it is difficult to turn the ship around, and it may take time to move the ship to the target point. Also, for example, although it is conceivable to increase the thrust to turn the ship around, in that case, the displacement of the ship in the fore-and-aft direction with respect to the target point becomes large, so there is a risk that the accuracy of the position-keeping control will decrease.

[0005] An object of the present disclosure is to enable a ship to be easily kept at a target point in position-keeping control by automatic ship steering and to improve the accuracy of the position-keeping control.

Means for Solving the Problems

[0006] A system according to one aspect of the present disclosure is a system for controlling a ship, comprising a ship propulsion system and a controller. The ship propulsion system generates thrust to propel the ship. The ship propulsion system includes an upper section, a lower section supported relative to the upper section so as to be steerable around a rudder axis, and a propeller located in the lower section. The controller performs position-holding control, controlling the ship propulsion system to hold the ship at a target location by pointing the bow or stern of the ship towards the target location and then moving the ship toward the target location. The position-holding control includes turning control for pointing the bow or stern of the ship toward the target location. The turning control of the position-holding control includes a first turning control and a second turning control. The first turning control controls the output of the ship propulsion system and the direction of rotation of the propeller based on information about the ship's target location and the ship's position, and controls the rudder angle within a predetermined angular range. The second turn control controls the direction of propeller rotation based on information about the ship's target location and the ship's position, and also controls the rudder angle to a first angle greater than the maximum rudder angle within a predetermined angle range. In the turn control of the position-holding control, the controller executes the second turn control if the difference between the target bearing corresponding to the target location and the ship's bearing is greater than or equal to a predetermined value and the output of the ship's propeller is less than or equal to a predetermined first output; otherwise, it executes the first turn control.

[0007] In the system disclosed herein, the ship's propeller is supported such that the lower section, where the propeller is located, is steerable relative to the upper section around the steering axis. Therefore, compared to a ship's propeller where the lower section steers together with the upper section, for example, the steering angle range of the ship's propeller can be increased. Furthermore, in the turning control of the position-holding control, the controller executes a second response control that controls the steering angle to a first angle larger than the maximum steering angle obtained by the first turning control if the difference between the target bearing corresponding to the target point and the ship's bearing is greater than or equal to a predetermined value and the output of the ship's propeller is less than or equal to a predetermined first output. In the second turning control, it becomes possible to turn the ship approximately in place. Therefore, even when the amount of longitudinal positional deviation of the ship relative to the target point is small, it becomes possible to turn the ship toward the target point, and the amount of longitudinal positional deviation can be suppressed. As a result, in position-holding control, the ship can be easily held at the target point, and the accuracy of position-holding control can be improved. [Effects of the Invention]

[0008] According to this disclosure, in position-holding control by automated ship handling, it is possible to easily keep the ship at a target location and improve the accuracy of position-holding control. [Brief explanation of the drawing]

[0009] [Figure 1] This is a plan view showing a ship equipped with a ship propulsion system according to the embodiment. [Figure 2] This is a side view of a ship's propulsion system. [Figure 3] This is a diagram to explain electric motors. [Figure 4] This is a schematic diagram showing the configuration of the ship handling system. [Figure 5] This is a front view of the joystick. [Figure 6] This diagram shows the movement of a ship in position-holding control. [Figure 7] This flowchart shows the processes performed by the ship's steering controller. [Figure 8] This is a plan view showing a ship equipped with a ship propulsion system according to another embodiment. [Modes for carrying out the invention]

[0010] Embodiments will be described below with reference to the drawings. Figure 1 is a perspective view showing a vessel 10 on which the steering system 100 according to the embodiment is installed. The vessel 10 comprises a hull 2 ​​and a ship propulsion system 3. In detail, the vessel 10 comprises a single ship propulsion system 3. In this embodiment, the ship propulsion system 3 is an electric outboard motor. The ship propulsion system 3 is mounted on the stern of the hull 2 ​​of the vessel 10. The ship propulsion system 3 is located in the center of the ship 10 in the left-right direction at the stern. The ship propulsion system 3 generates thrust to propel the vessel 10.

[0011] Figure 2 is a side view of the ship's propulsion unit 3. The ship's propulsion unit 3 is attached to the hull 2 ​​via a bracket 11. The ship's propulsion unit 3 is supported by the bracket 11.

[0012] The ship's propulsion system 3 includes an upper section 12, a lower section 13, a propeller 14, a steering device 15, and an electric motor 16 (see Figure 3). The upper section 12 is attached to a bracket 11. The lower section 13 is located below the bracket 11. The lower section 13 is supported so as to be steerable around the axis of a steering shaft 15a, which will be described later, relative to the upper section 12. The lower section 13 includes a case section 13a and a duct 13b. The case section 13a is provided integrally with the duct 13b. The duct 13b is located below the case section 13a. The duct 13b is formed in a cylindrical shape. The propeller 14 is located in the duct 13b of the lower section 13. The propeller 14 generates thrust by rotating due to the driving force of the electric motor 16.

[0013] The steering device 15 is configured to steer the lower section 13. By steering the lower section 13, the steering device 15 changes the direction of the thrust generated by the rotation of the propeller 14. The steering device 15 includes a steering shaft 15a. The steering shaft 15a extends in the vertical direction. The steering shaft 15a is connected to the duct 13b of the upper section 12 and the lower section 13. The steering device 15 includes a motor (not shown) for rotating the steering shaft 15a around the axis of the steering shaft 15a. In this embodiment, the lateral rotation range of the lower section 13 of the ship's propulsion system 3 is approximately 140 degrees (70 degrees to the left and 70 degrees to the right). Therefore, the steering device 15 is configured to steer the lower section 13 within a range of 140 degrees.

[0014] The electric motor 16 is powered and driven by a battery (not shown) located in the hull 2. The electric motor 16 includes a stator section 16a and a rotor section 16b. The stator section 16a is fixed to the duct 13b. The stator section 16a includes coils (not shown). The rotor section 16b is fixed to the propeller 14. The stator section 16a is positioned opposite the rotor section 16b. The rotor section 16b includes a plurality of magnets (not shown). By energizing the coils of the stator section 16a, the propeller 14 rotates together with the rotor section 16b.

[0015] Figure 4 is a schematic diagram showing the configuration of the ship steering system 100. The ship propulsion system 3 includes a motor controller 17 and a steering controller 18. The motor controller 17 and the steering controller 18 are control circuits that include a processor such as a CPU and memory such as RAM or ROM. The motor controller 17 stores programs and data for controlling the electric motor 16. The motor controller 17 controls the rotation direction and output of the electric motor 16 in accordance with command signals output from the ship steering controller 30, which will be described later.

[0016] The steering controller 18 controls the drive of the steering gear 15 according to a command signal output from the vessel control controller 30. The steering controller 18 stores a program and data for controlling the steering gear 15.

[0017] The vessel control system 100 includes a steering wheel 24, a remote controller 25, a joystick 26, and a setting device 27. The steering wheel 24, the remote controller 25, the joystick 26, and the setting device 27 are arranged at the vessel control station 10b of the vessel 10. The vessel control station 10b is arranged forward of the center of gravity of the vessel 10 in the fore-and-aft direction. The steering wheel 24, the remote controller 25, the joystick 26, and the setting device 27 are manually operable.

[0018] The steering wheel 24 is a device for an operator to operate the turning direction of the vessel 10. The steering wheel 24 includes a sensor 24a. The sensor 24a outputs a steering signal indicating the operation direction and operation amount of the steering wheel 24.

[0019] The remote controller 25 includes a throttle lever 25a. The throttle lever 25a is a device for an operator to adjust the magnitude of the thrust of the vessel propeller 3. Also, the throttle lever 25a is a device for an operator to switch the direction of the thrust of the vessel propeller 3 between forward and reverse. The throttle lever 25a is operable from a neutral position to a forward position and a reverse position. The neutral position is a position between the forward position and the reverse position. The throttle lever 25a includes a sensor 25b. The sensor 25b outputs a throttle signal indicating the operation direction and operation amount of the throttle lever 25a.

[0020] The joystick 26 can be tilted forward / backward and left / right (lateral) from a neutral position. In other words, the joystick 26 can be tilted in all directions. The joystick 26 can rotate around the rotation axis Ax1. In other words, the joystick 26 can be twisted clockwise and counterclockwise around the rotation axis Ax1. The joystick 26 includes a sensor 26a. The sensor 26a outputs an operation signal indicating the operation of the joystick 26. The operation signal includes the tilt direction and amount of the joystick 26. The operation signal also includes the twist direction and amount of the joystick 26. The rudder angle, output magnitude, and output direction of the ship's propulsion system 3 are controlled according to the amount and direction of the tilt of the joystick 26.

[0021] Figure 5 is a front view of the joystick 26. The joystick 26 includes a joystick button 26b and a position hold button 31b. The joystick button 26b is a button for switching between joystick mode, in which the ship 10 is operated using the joystick 26, and normal mode, in which the ship 10 is operated using the remote controller 25 and the steering wheel 24. The position hold button 31b is a button that accepts the start and end operations for position hold control.

[0022] The setting device 27 is located on the joystick 26. The setting device 27 is used in joystick mode. The setting device 27 allows selection of one thrust level from multiple thrust levels. The setting device 27 allows selection of one thrust level from five levels, for example, from level 1 to level 5, when maneuvering the ship using the joystick 26.

[0023] The higher the thrust level, the greater the upper limit of the thrust output from the ship's propulsion system 3 (maximum thrust). In other words, the output of the ship's propulsion system 3, in response to the tilt amount of the joystick 26, increases as the thrust level increases.

[0024] The setting device 27 includes a plus switch 27a and a minus switch 27b. Pressing the plus switch 27a once increases the thrust level by one step. Pressing the minus switch 27b once decreases the thrust level by one step. The setting device 27 outputs a setting signal indicating the thrust level according to the operator's operation. Note that the setting device 27 is not limited to switches, but may also be a touchscreen.

[0025] The ship handling system 100 includes a ship handling controller 30. The ship handling controller 30 includes a processor such as a CPU and memory such as RAM or ROM. The ship handling controller 30 stores programs and data for controlling the ship's propulsion system 3. The ship handling controller 30 is connected to the motor controller 17 and the steering controller 18 via wired or wireless connections. The ship handling controller 30 is connected to the steering wheel 24, remote controller 25, joystick 26, and setting device 27 via wired or wireless connections.

[0026] The ship steering controller 30 outputs command signals to the motor controller 17 and the steering controller 18 based on signals from sensors 24a and 25b. The ship steering controller 30 controls the rudder angle, output magnitude, and output direction of the ship's propulsion system 3 via the motor controller 17 and the steering controller 18. The ship steering controller 30 controls the direction of the output of the ship's propulsion system 3 by controlling the rotation direction of the propeller 14.

[0027] The steering controller 30 receives operation signals from the setting device 27. The steering controller 30 controls the rudder angle and the magnitude and direction of the output of the ship's propulsion system 3 according to the selected thrust level and the tilt direction and amount of the joystick 26. The steering controller 30 controls the ship's propulsion system 3 to output a thrust of a magnitude corresponding to the amount of tilt in the direction corresponding to the tilt, within the range up to the upper limit of thrust corresponding to the thrust level. The steering controller 30 increases the output of the ship's propulsion system 3 according to the amount of tilt of the joystick 26 as the thrust level increases.

[0028] The steering controller 30 changes the rudder angle of the ship's propulsion system 3 so that the ship 10 turns in a direction corresponding to the twisting direction of the joystick 26. The steering controller 30 generates thrust in the ship's propulsion system 3 according to the amount of twisting of the joystick 26.

[0029] The steering controller 30 changes the rudder angle of the ship's propeller 3 so that the ship 10 turns in response to the forward or backward tilting and twisting operations of the joystick 26. At this time, the steering controller 30 generates thrust in the ship's propeller 3 according to the amount of tilting and changes the rudder angle of the ship's propeller 3 so that the ship 10 turns in the direction corresponding to the twisting direction.

[0030] The ship handling system 100 includes a position sensor 31 and a compass sensor 32. The position sensor 31 is a receiver for a GNSS (Global Navigation Satellite System), such as a GPS (Global Positioning System). The position sensor 31 outputs a signal indicating the current position of the ship 10. The position sensor 31 is communicatively connected to the ship handling controller 30. The ship handling controller 30 obtains the position of the ship 10 from the signal from the position sensor 31.

[0031] The direction sensor 32 detects the current bearing of the vessel 10. The direction sensor 32 is, for example, an IMU (inertial measurement unit). The direction sensor 32 is communicated with the ship steering controller 30.

[0032] The ship steering controller 30, for example, when it receives an operation signal output in response to the operation of the position holding button 31b, performs position holding control by controlling the ship's propulsion system 3 to hold the ship 10 at the target point P0 (see Figure 6). The target point P0 is, for example, the position of the ship 10 at the time the operation signal is received from the position holding button 31b. In position holding control, the ship steering controller 30 controls the ship's propulsion system 3 to hold the ship 10 at the target point P0 by first pointing the bow or stern of the ship 10 towards the target point P0 and then moving the ship 10 toward the target point. In position holding control, for example, if the distance from the ship 10's current position P1 to the target point P0 exceeds a predetermined distance, the ship steering controller 30 moves the ship 10 toward the target point.

[0033] In position holding control, the ship steering controller 30 controls the magnitude of the thrust generated by the ship's propulsion system 3 according to the amount of longitudinal positional deviation of the ship 10 relative to the target point P0. In position holding control, the thrust generated by the ship's propulsion system 3 is controlled to be smaller the smaller the longitudinal positional deviation of the ship 10 relative to the target point P0.

[0034] Position holding control includes turning control to orient the bow or stern of the vessel 10 toward the target point P0. In the turning control, the user may select whether to orient the bow or stern of the vessel 10 toward the target point P0, or the steering controller 30 may automatically determine this based on the detection results of a direction sensor or the like.

[0035] The turning control includes a first turning control and a second turning control. The first turning control controls the output of the ship's propeller 3 and the direction of rotation of the propeller 14 based on information about the ship's target point P0 and the ship's position information, and also controls the rudder angle to be within a predetermined angular range. The predetermined angular range is, for example, 80 degrees (40 degrees to the left and 40 degrees to the right).

[0036] The second turn control controls the rotation direction of the propeller 14 based on information regarding the target point of the vessel 10 and the position information of the vessel 10, and controls the steering angle to a first angle that is greater than the maximum steering angle within a predetermined angle range. Figure 6 is a schematic diagram showing the movement of the vessel 10 in the second turn control. The second turn control controls the steering angle to a steering angle greater than the maximum steering angle that can be steered in the first turn control (40 degrees in this case). The first angle is, for example, 70 degrees. In this embodiment, the first angle is the maximum steering angle that the lower section 13 of the ship's propeller 3 can steer. In the second turn control, it is possible to turn the vessel 10 in place approximately around its center of gravity.

[0037] In the position-holding control shown in Figure 6, the second turn control turns the ship 10 so that its bow faces the target point P0. Here, the steering controller 30 steers the rudder 70 degrees to the right and controls the rotation direction of the propeller 14 so that thrust is generated in the reverse direction.

[0038] The first angle is preferably set to 60 degrees or more and 80 degrees or less. By setting the first angle to 60 degrees or more and 80 degrees or less, when the ship 10 is turning during the second turning control, the operator can get the feeling that the ship 10 is turning around the steering seat 10b.

[0039] The steering controller 30 executes a second turn control in position-holding control if it finds that the difference between the target bearing corresponding to the target point and the bearing of the ship is greater than or equal to a predetermined value and the output of the ship's propulsion system 3 is less than or equal to a predetermined first output. If this condition is not met, it executes a first turn control. An example of a situation where this condition is met is when the amount of longitudinal displacement of the ship relative to the target point is small, and as a result the thrust required to turn the ship 10 is small. If the condition is met during the execution of the first turn control, the steering controller 30 switches from the first turn control to the second turn control.

[0040] The predetermined value is, for example, 10 degrees. The predetermined first output is set to correspond to the thrust generated by the ship's propulsion system 3 when, for example, the amount of longitudinal displacement of the ship 10 relative to the target point is small.

[0041] The steering controller 30 controls the output of the ship's propulsion system 3 to a predetermined second output during the second turn control. The steering controller 30 changes the predetermined second output according to the thrust level set by the setting device 27 during the second turn control. The steering controller 30 increases the predetermined second output as the thrust level increases during the second turn control.

[0042] In the second turn control, the steering controller 30 stops the output of the ship's propeller 3 until the steering angle exceeds a second angle, which is larger than a predetermined angle range and smaller than the first angle, when the steering angle is turned to a first angle. The second angle is, for example, 60 degrees. In other words, in the second turn control, the steering controller 30 stops the output of the ship's propeller 3 until the steering angle is turned from the predetermined angle range to the first angle. This suppresses the generation of thrust in the longitudinal direction between the steering angle and the second angle, thereby suppressing displacement of the ship 10 in the longitudinal direction.

[0043] Figure 7 is a flowchart showing the position holding control process performed by the ship steering controller 30. In step S1, it is determined whether the distance from the current position P1 of the ship 10 to the target point P0 exceeds a predetermined distance. If it is determined that the distance exceeds the predetermined distance, the ship steering controller 30 executes the process in step S2.

[0044] In step S2, the steering controller 30 determines whether the aforementioned determination conditions are met. If it determines that the determination conditions are met, the steering controller 30 performs the second turn control (step S3). If it determines that the determination conditions are not met, the steering controller 30 performs the first turn control (step S6).

[0045] In steps S4 and S7, the ship steering controller 30 determines whether the bow or stern of the ship 10 is facing the target point. If it determines in steps S4 and S7 that the bow or stern of the ship 10 is facing the target point, the ship steering controller moves the ship 10 in the forward or backward direction toward the target point.

[0046] In step S4, if it is determined that the bow or stern of vessel 10 is not facing the target point, The steering controller continues the second turn control. In step S7, if it is determined that the bow or stern of the vessel 10 is not facing the target point, the first turn control is continued. If the steering controller 30 determines that the determination conditions are met during the execution of the first turn control, it switches from the first turn control to the second turn control.

[0047] In the ship steering system 100 according to the embodiment described above, the ship propeller 3 is supported such that the lower section 13 on which the propeller 14 is located can be steered relative to the upper section 12 around the steering axis. Therefore, compared to a ship propeller in which the lower section 13 steers together with the upper section 12, for example, the steering angle range of the ship propeller can be increased. Furthermore, in the turning control of the position holding control, the ship steering controller 30 executes a second response control that controls the steering angle to a first angle that is larger than the maximum steering angle obtained by the first turning control, when the difference between the target bearing corresponding to the target point and the bearing of the ship is greater than or equal to a predetermined value and the output of the ship propeller 3 is less than or equal to a predetermined first output. In the second turning control, it becomes possible to turn the ship 10 in place, so even if the amount of longitudinal positional deviation of the ship 10 relative to the target point is small, it becomes possible to turn the ship 10 toward the target point, and the longitudinal positional deviation of the ship 10 can be suppressed. As a result, in position holding control, the ship 10 can be easily kept at the target location, and the accuracy of position holding control can be improved.

[0048] Although one embodiment of the present invention has been described above, the present invention is not limited to the above embodiment, and various modifications are possible without departing from the spirit of the invention.

[0049] As shown in Figure 8, the steering system 100 may further include a main propulsion system 40. The main propulsion system 40 may be an outboard motor including an internal combustion engine or an electric outboard motor. The main propulsion system 40 is located in the center of the lateral direction of the vessel 10 at the stern. In this case, the vessel propulsion system 3 may function as an auxiliary propulsion system located off-center to one side of the lateral direction of the vessel 10 at the stern.

[0050] The rotatable range of the lower section 13 of the ship's propulsion system 3 is not limited to the above embodiment. For example, the rotatable range of the lower section 13 in the left-right direction may be 180 degrees to the left and 120 degrees to the right and 120 degrees to the left and 120 degrees to the right. [Explanation of Symbols]

[0051] 3: Ship propulsion system, 10: Ship, 12: Upper section, 13: Lower section, 14: Propeller, 27: Setting device, 30: Ship steering controller, 100: Ship steering system

Claims

1. A system for controlling ships, A ship propulsion system comprising an upper section, a lower section supported so as to be steerable around a steering axis relative to the upper section, and a propeller positioned on the lower section, which generates thrust to propel the ship, A controller that performs position-holding control, including turning control to point the bow or stern of the vessel toward the target point, and then controlling the ship's propulsion system to hold the vessel toward the target point by moving the vessel toward the target point after pointing the bow or stern of the vessel toward the target point, Equipped with, The rotation control of the position holding control is as follows: Based on information regarding the target location of the vessel and the position information of the vessel, the output of the ship's propeller and the direction of rotation of the propeller are controlled, and the steering angle is controlled within a predetermined angular range (first rotation control), A second turning control controls the direction of rotation of the propeller based on information regarding the target point of the vessel and the position information of the vessel, and controls the steering angle to a first angle that is greater than the maximum steering angle within the predetermined angle range. Includes, The controller, in the turning control of the position holding control, executes the second turning control if the difference between the target bearing corresponding to the target point and the bearing of the ship is greater than or equal to a predetermined value and the output of the ship's propulsion system is less than or equal to a predetermined first output, and executes the first turning control if the above conditions are not met. system.

2. In the second turning control, the controller controls the output of the ship's propulsion system to a predetermined second output. The system according to claim 1.

3. It further includes a setting device that allows selection of one thrust level from multiple thrust levels. In the second turning control, the controller changes the predetermined second output according to the thrust level set by the setting device. The system according to claim 2.

4. In the second turning control, the controller stops the output of the ship's propulsion system until the steering angle exceeds a second angle that is greater than the predetermined angle range and smaller than the first angle, when steering the steering angle to the first angle. The system according to claim 1.

5. The first angle is set to be 60 degrees or more and 80 degrees or less. The system according to claim 1.

6. The aforementioned vessel is further equipped with a helmsman's seat, The aforementioned steering position is positioned forward of the ship's center of gravity in the longitudinal direction. The system according to claim 5.

7. The aforementioned ship propulsion system is an electric outboard motor including an electric motor, and is located at the stern, centered in the left-right direction of the ship. The system according to claim 6.

8. The ship is further equipped with a main propulsion device located at the center of the ship in the left-right direction at the stern, which generates thrust to propel the ship. The aforementioned ship's propulsion system is positioned at the stern of the ship, biased towards one side in the left-right direction of the ship. The system according to claim 7.

9. The hull and, The system according to claim 1, which is arranged on the hull of the ship, A ship equipped with the following features.

Images