Ship monitoring system, ship monitoring method, information processing device, and program

Abstract

[Problem] To provide a ship monitoring system with which it is possible to improve OZT visibility. [Solution] This ship monitoring system comprises: a first data generation unit that generates first ship data showing the position and speed of a first ship; a second data generation unit that generates second ship data showing the position and speed of a second ship; a risk value calculation unit that, on the basis of the first ship data and the second ship data, calculates a risk value showing the risk of the first ship and the second ship colliding when it is assumed that the first ship veers and arrives at each point on the predicted course of the second ship; a range specification unit that specifies a range within which two or more points at which the risk value is greater than or equal to a threshold value are continuous; and a display unit that displays a risk region including the range within which the two or more points at which the risk value is greater than or equal to a threshold value are continuous.

Description

[Technical Field]

[0001] The present invention relates to a ship monitoring system, a ship monitoring method, an information processing device, and a program. [Background technology]

[0002] Conventionally, there are various methods for evaluating the risk of collision between ships. For example, Non-Patent Document 1 discloses a method for displaying an OZT (Obstacle Zone by Target) as a risk area. [Prior art documents] [Patent documents]

[0003] [Non-Patent Document 1] Imazu, Junji Fukuto, Masayoshi Numano, "About the Obstruction Zone and its Display by Other Vessels", Journal of the Japan Institute of Navigation, 2002, Vol. 107, pp. 191-197 Summary of the Invention [Problem to be solved by the invention]

[0004] However, in the method of displaying OZT as a risk area, multiple circular OZTs are displayed overlapping on the predicted course of other ships, which can make them difficult to see.

[0005] The present invention has been made in consideration of the above-mentioned problems, and its main purpose is to provide a ship monitoring system, a ship monitoring method, an information processing device, and a program that can improve the visibility of risk areas. [Means for solving the problem]

[0006] In order to solve the above problem, one embodiment of the ship monitoring system of the present invention comprises a first data generation unit that generates first ship data representing the position and speed of a first ship, a second data generation unit that generates second ship data representing the position and speed of a second ship, a risk value calculation unit that calculates, for each point on the predicted course of the second ship based on the first ship data and the second ship data, a risk value that represents the risk of collision between the first ship and the second ship when assuming that the first ship changes course and reaches each point, a range identification unit that identifies a range in which two or more consecutive points have risk values above a threshold, and a display unit that displays a risk area including the range in which two or more consecutive points have risk values above a threshold.

[0007] In another aspect of the ship monitoring method of the present invention, a first data generation unit generates first ship data representing the position and speed of a first ship, and a second data generation unit generates second ship data representing the position and speed of a second ship.Based on the first ship data and the second ship data, for each point on the predicted course of the second ship, calculates a risk value representing the risk of collision between the first ship and the second ship when assuming that the first ship changes course and reaches each point, identifies a range in which two or more consecutive points have risk values above a threshold, and displays a risk area including the range in which two or more consecutive points have risk values above the threshold.

[0008] In addition, another aspect of the information processing device of the present invention includes a risk value calculation unit that calculates a risk value representing the risk of collision between the first ship and the second ship for each point on the predicted course of the second ship based on first ship data representing the position and speed of the first ship and second ship data representing the position and speed of the second ship, when it is assumed that the first ship changes course and reaches each of the points; a range identification unit that identifies a range in which two or more consecutive points have risk values above a threshold; and a display control unit that displays a risk area including the range in which two or more consecutive points have risk values above a threshold.

[0009] In addition, another aspect of the program of the present invention causes a computer to perform the following steps: calculate a risk value representing the risk of collision between the first vessel and the second vessel for each point on the predicted course of the second vessel, based on first vessel data representing the position and speed of the first vessel and second vessel data representing the position and speed of the second vessel, when it is assumed that the first vessel changes course and reaches each of the points; identify a range in which two or more consecutive points have risk values above a threshold; and display a risk area including the range in which two or more consecutive points have risk values above the threshold. [Effects of the Invention]

[0010] According to the present invention, it is possible to improve the visibility of risk areas. [Brief explanation of the drawings]

[0011] [Figure 1] 1 is a diagram illustrating an example of the configuration of a vessel monitoring system according to an embodiment. [Figure 2] FIG. 2 is a diagram illustrating an example of a other ship management database. [Figure 3] FIG. 1 is a diagram showing a display example (conventional example) of OZT. [Figure 4] FIG. 1 is a diagram illustrating an example of the configuration of an information processing device according to an embodiment. [Figure 5] FIG. 10 is a diagram showing a display example of a comprehensive OZT. [Figure 6] FIG. 10 is a diagram showing a modified example of a display example of a comprehensive OZT. DETAILED DESCRIPTION OF THE INVENTION

[0012] Hereinafter, an embodiment of the present invention will be described with reference to the drawings.

[0013] Fig. 1 is a block diagram showing an example of the configuration of a ship monitoring system 100 according to an embodiment. A ship monitoring method according to an embodiment is realized in the ship monitoring system 100. The ship monitoring system 100 is a system that is installed on a ship and monitors ships present in the vicinity.

[0014] The vessel equipped with the vessel monitoring system 100 is an example of a first vessel, and will be referred to as the "own vessel" in the following description. The vessels present around the own vessel are examples of second vessels, and will be referred to as the "other vessels" in the following description.

[0015] In the following description, "speed" is a vector quantity representing speed and direction (so-called ship speed vector), and "velocity" is a scalar quantity.

[0016] The vessel monitoring system 100 includes an information processing device 1, a display unit 2, a radar 3, an AIS 4, a GNSS receiver 5, a gyrocompass 6, an ECDIS 7, and an alarm unit 8. These devices are connected to a network N such as a LAN, and are capable of network communication with each other.

[0017] The information processing device 1 is a computer including a CPU, RAM, ROM, nonvolatile memory, an input / output interface, etc. The CPU of the information processing device 1 executes information processing in accordance with a program loaded from the ROM or nonvolatile memory to the RAM.

[0018] The program may be supplied via an information storage medium such as an optical disk or a memory card, or may be supplied via a communication network such as the Internet or a LAN.

[0019] The display unit 2 is, for example, a display device with a touch sensor. The touch sensor detects a position on the screen pointed to by a finger or the like. The pointed position may be input by a trackball or the like, instead of the touch sensor.

[0020] The radar 3 emits radio waves around the ship and receives the reflected waves, generating echo data based on the received signals. The radar 3 also identifies targets from the echo data and generates target tracking data (TT data) that indicate the position and speed of the targets.

[0021] The AIS (Automatic Identification System) 4 receives AIS data from other ships around the ship or from land-based control. Instead of AIS, a VDES (VHF Data Exchange System) may also be used. The AIS data includes the position and speed of other ships.

[0022] The GNSS receiver 5 detects the ship's position based on radio waves received from the GNSS (Global Navigation Satellite System). The gyrocompass 6 detects the ship's heading. A GPS compass or a magnetic compass may be used instead of a gyrocompass.

[0023] An ECDIS (Electronic Chart Display and Information System) 7 acquires the ship's position from the GNSS receiver 5 and displays the ship's position on an electronic chart. The ECDIS 7 also displays the ship's planned route on the electronic chart. A GNSS plotter may be used instead of an ECDIS.

[0024] The warning unit 8 issues a warning when there is a risk of collision between the ship and another ship. The warning unit 8 may issue a warning by display, sound, or light, for example. A warning by display may be issued by the display unit 2. In other words, the display unit 2 may also function as the warning unit 8.

[0025] In this embodiment, the information processing device 1 is an independent device, but is not limited to this and may be integrated with another device such as the ECDIS 7. In other words, the functional units of the information processing device 1 may be realized by another device such as the ECDIS 7.

[0026] Furthermore, the display unit 2 is also an independent device, but is not limited to this. A display unit of another device such as the ECDIS 7 may be used as the display unit 2 that displays the image generated by the information processing device 1.

[0027] In this embodiment, the combination of the GNSS receiver 5 and the ECDIS 7 is an example of a first data generator, which generates ship data indicating the ship's position and speed. Specifically, the GNSS receiver 5 detects the ship's position, and the ECDIS 7 detects the ship's speed from changes in the ship's position over time.

[0028] However, the speed of the ship may be detected based on the direction of the ship detected by the gyrocompass 6 and the speed of the ship detected by a ship's speedometer (not shown).

[0029] The radar 3 or the AIS 4 is an example of a second data generator, and generates other ship data indicating the position and speed of other ships. Specifically, the TT data generated by the radar 3 corresponds to other ship data. The AIS data generated by the AIS 4 also corresponds to other ship data.

[0030] 2 is a diagram showing an example of the other ship management database constructed in the memory of the information processing device 1. Other ship data generated by the radar 3 or the AIS 4 is registered in the other ship management database.

[0031] The other ship management database includes fields such as "other ship identifier," "position," "speed," and "direction." The positions and directions of other ships detected by radar 3 are converted into the same coordinate system as GNSS.

[0032] Fig. 3 shows an example of an OZT display (conventional example). An OZT (Obstacle Zone by Target) is a zone in which the navigation of one ship is obstructed by other ships, and is displayed on the predicted course of the other ships.

[0033] In the method of displaying OZT, a collision risk value is calculated at each of multiple judgment points set discretely on the other ship's predicted course, and a circular OZT is displayed at judgment points where the risk value is above a threshold.If there are consecutive judgment points where the risk value is above the threshold, the edges of the multiple overlapping OZTs will be uneven, which may reduce visibility.

[0034] By shortening the interval between decision points, it is possible to make the unevenness of the edges of multiple OZTs less noticeable, but this increases the computational load.On the other hand, if the interval between decision points is made longer than the diameter of the OZT, the OZT will not be displayed in the position where it should be displayed, so the interval between decision points is limited to less than the diameter of the OZT.

[0035] Therefore, in this embodiment, as will be described below, a comprehensive OZT including two or more decision points is displayed as a risk area to improve visibility.

[0036] Fig. 4 is a diagram showing an example of the configuration of an information processing device 1 according to an embodiment, which realizes the ship monitoring method according to the embodiment. The information processing device 1 includes a risk value calculation unit 11, an OZT range identification unit 12, and a display control unit 13. These functional units are realized by the CPU of the information processing device 1 executing information processing in accordance with a program. Fig. 5 is a diagram showing an example of the display of a comprehensive OZT. The comprehensive OZT is an example of a risk area.

[0037] The risk value calculation unit 11 calculates a risk value representing the risk of collision between the ship and the other ship, assuming that the ship changes course and reaches each decision point on the predicted course of the other ship, based on the ship's own data and the other ship's data. A known method for displaying OZT is used to calculate the risk value.

[0038] Specifically, the risk value calculation unit 11 calculates the probability that the ship and the other ship will be at the same time at the decision point, assuming that the ship changes course from its current position while maintaining its speed and reaches the decision point, and that the other ship will reach the decision point while maintaining its speed from its current position, as the collision risk value.The point where the risk value is equal to or greater than the threshold is then determined as the OZT display point.

[0039] The OZT range specifying unit 12 specifies a range where two or more consecutive points (OZT display points) have a risk value equal to or greater than a threshold as the OZT display range. Specifically, the OZT range specifying unit 12 specifies an OZT display point that is the start point and an OZT display point that is the end point of the range where two or more consecutive OZT display points are present.

[0040] The display control unit 13 displays a comprehensive OZT including a range (OZT display range) where two or more consecutive points have a risk value equal to or greater than the threshold on the display unit 2 (see Figure 1). As shown in Figure 5, the image displayed includes the comprehensive OZT along with the ship's symbol, the ship's bow line, the other ship's symbols, and the other ship's predicted course.

[0041] Specifically, the comprehensive OZT has a shape extending in the same direction as the other ship's predicted course, for example, a rounded rectangle with semicircular ends. The comprehensive OZT is not limited to this, and may also have an elliptical shape. The edge of the comprehensive OZT between the start point and the end point is a straight line (hereinafter referred to as an envelope) that extends along the other ship's predicted course.

[0042] The distance between the envelope of the comprehensive OZT and the predicted course of the other ship, as well as the radius of the semicircles at both ends of the comprehensive OZT, uses a predetermined safe separation distance, similar to the radius of a conventional circular OZT (see Figure 3).

[0043] In the above explanation, the straight line connecting the semicircles at both ends of the comprehensive OZT is conveniently called the "envelope", but the envelope is not actually obtained by arranging a large number of circular OZTs with minute intervals between the decision points.

[0044] As described above, in this embodiment, the comprehensive OZT is displayed in a range where two or more consecutive points have a risk value equal to or greater than the threshold, thereby improving visibility. In particular, the comprehensive OZT has a linear edge that extends along the predicted course of the other ship, which improves visibility compared to conventional uneven edges.

[0045] As shown in Fig. 6, the display control unit 13 may change the display mode of the comprehensive OZT according to the risk value of each judgment point included in the comprehensive OZT. Specifically, the shading of the part to which each judgment point of the comprehensive OZT belongs is changed so that it becomes darker as the risk value increases, for example. Not limited to this, other display modes such as color or texture may also be changed.

[0046] Although the embodiments of the present invention have been described above, the present invention is not limited to the above-described embodiments, and it goes without saying that various modifications can be made by those skilled in the art. [Explanation of symbols]

[0047] 1 Information processing device, 2 Display unit, 3 Radar, 4 AIS, 5 GNSS receiver, 6 Gyrocompass, 7 ECDIS, 8 Alarm unit, 11 Risk value calculation unit, 12 OZT range identification unit, 13 Display control unit, 100 Ship monitoring system

Claims

1. a first data generation unit that generates first vessel data representing the position and velocity of the first vessel; a second data generation unit that generates second vessel data representing the position and velocity of the second vessel; a risk value calculation unit that calculates, for each point on the predicted course of the second vessel, a risk value that represents a risk of collision between the first vessel and the second vessel when it is assumed that the first vessel changes course and reaches each point, based on the first vessel data and the second vessel data; a range specifying unit that specifies a range in which two or more consecutive points have a risk value equal to or greater than a threshold; a display unit that displays a risk area including a range where two or more consecutive points have a risk value equal to or greater than a threshold; A vessel monitoring system comprising:

2. the range specifying unit specifies a start point and an end point of a range in which two or more consecutive points have a risk value equal to or greater than a threshold value; The vessel monitoring system of claim 1 .

3. the risk area extends in the same direction as the predicted course of the second vessel; 3. A vessel monitoring system according to claim 1 or 2.

4. a portion of the edge of the risk area between a start point and an end point of a range in which two or more consecutive points have a risk value equal to or greater than a threshold value extends along the predicted course of the second vessel; 4. A vessel monitoring system according to claim 1.

5. the display unit changes the display mode of the risk area according to the risk value of each of the points included in the risk area.

5. A vessel monitoring system according to claim 1.

6. the display unit changes the shading of a portion of the risk region to which each of the points belongs according to the risk value of each of the points included in the risk region.

6. A vessel monitoring system according to claim 5.

7. the first data generation unit is mounted on the first vessel and includes a GNSS (Global Navigation Satellite System) receiver that detects the position of the first vessel based on radio waves received from a GNSS; 7. A vessel monitoring system according to any one of claims 1 to 6.

8. the second data generation unit includes a radar mounted on the first vessel and configured to detect the position and speed of the second vessel from echo data generated by receiving reflected waves of radio waves emitted around the first vessel; 8. A vessel monitoring system according to any one of claims 1 to 7.

9. a first data generation unit generating first vessel data representing the position and velocity of the first vessel; a second data generation unit generating second vessel data representing the position and velocity of the second vessel; a risk value calculation unit calculates, based on the first vessel data and the second vessel data, a risk value representing the risk of collision between the first vessel and the second vessel for each point on the predicted course of the second vessel when it is assumed that the first vessel changes course and reaches each point; a range specifying unit specifying a range in which two or more consecutive points have a risk value equal to or greater than a threshold; a display unit displays a risk region including a range where two or more consecutive points have a risk value equal to or greater than a threshold value; Ship monitoring methods.

10. a risk value calculation unit that calculates, for each point on the predicted course of the second vessel, a risk value that represents a risk of collision between the first vessel and the second vessel when it is assumed that the first vessel will change course and reach each point, based on first vessel data that represents the position and speed of the first vessel and second vessel data that represents the position and speed of the second vessel; a range specifying unit that specifies a range in which two or more consecutive points have a risk value equal to or greater than a threshold; a display control unit that displays a risk area including a range in which two or more consecutive points have a risk value equal to or greater than a threshold; An information processing device comprising:

11. calculating, for each point on the predicted course of the second vessel, a risk value representing the risk of collision between the first vessel and the second vessel when it is assumed that the first vessel will change course and reach each point, based on first vessel data representing the position and speed of the first vessel and second vessel data representing the position and speed of the second vessel; Identifying a range in which two or more consecutive points have a risk value equal to or greater than a threshold; and Displaying a risk area including a range where two or more consecutive points have a risk value equal to or greater than a threshold value; A program that causes a computer to execute the following.

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