JP7664079B2 - Ship monitoring system, ship monitoring method, information processing device, and program - Google Patents

Description

The present invention relates to a ship monitoring system, a ship monitoring method, an information processing device, and a program.

Conventionally, there are various methods for evaluating the risk of collision between ships. For example, Non-Patent Document 1 discloses a method for displaying OZT (Obstacle Zone by Target).

Imazu, Junji Fukuto, Masayoshi Numano, "Obstruction Zones by Other Vessels and Their Indications", Journal of the Japan Institute of Navigation, Vol. 107, 2002, pp. 191-197

However, in the method of displaying OZT, the range of the other ship's predicted course where OZT is not displayed is the range in which the ship can navigate. However, in such a range, it is difficult to determine at a glance whether the ship will pass in front of or behind the other ship.

The present invention was made in consideration of the above-mentioned problems, and its main objective is to provide a ship monitoring system, ship monitoring method, information processing device, and program that makes it easy to determine whether a ship is passing in front of or behind another ship.

To solve the above problem, one embodiment of the ship monitoring system of the present invention includes 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 passing determination unit that determines, for each point on the predicted course of the second ship based on the first ship data and the second ship data, whether the first ship will pass in front of or behind the second ship when it is assumed that the first ship will change course and reach each point, and a display unit that displays, on the predicted course of the second ship, a forward passing range in which the first ship will pass in front of the second ship and a rear passing range in which the first ship will pass behind the second ship.

In another aspect of the ship monitoring method of the present invention, a first data generating unit generates first ship data representing the position and speed of a first ship, and a second data generating 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, it is determined for each point on the predicted course of the second ship whether the first ship will pass in front of or behind the second ship when it is assumed that the first ship will change course and reach each point, and a forward passing range in which the first ship will pass in front of the second ship and a rear passing range in which the first ship will pass behind the second ship are displayed on the predicted course of the second ship.

An information processing device according to another aspect of the present invention includes a passing determination unit that determines, for each point on the predicted course of the second ship, whether the first ship will pass in front of or behind the second ship when it is assumed that the first ship will change course and reach each point, 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, and a display control unit that generates a display image for displaying, on the predicted course of the second ship, a forward passing range in which the first ship will pass in front of the second ship and a rear passing range in which the first ship will pass behind the second ship.

In another aspect of the program of the present invention, a computer is caused to execute the following: 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, for each point on the predicted course of the second ship, when it is assumed that the first ship changes course and reaches each point, the computer determines whether the first ship will pass in front of or behind the second ship; and generates a display image on the predicted course of the second ship to display a forward passing range in which the first ship will pass in front of the second ship and a rear passing range in which the first ship will pass behind the second ship.

The present invention makes it easier to determine whether a ship is passing in front of or behind another ship.

1 is a diagram illustrating an example of the configuration of a vessel monitoring system according to an embodiment. FIG. 4 is a diagram showing an example of a other ship management database. FIG. 1 is a diagram illustrating an example of a configuration of an information processing device according to an embodiment. FIG. 1 is a diagram showing a display example (conventional example) of OZT. 5 is a diagram showing an example of a procedure of a vessel monitoring method according to an embodiment; FIG. 13 is a diagram for explaining calculations. FIG. 13 is a diagram showing an example of a display image. FIG. 13 is a diagram showing an example of a display image. FIG. 13 is a diagram showing an example of a display image. FIG. 13 is a diagram showing an example of a display image.

The following describes an embodiment of the present invention with reference to the drawings.

Figure 1 is a block diagram showing an example configuration of a ship monitoring system 100 according to an embodiment. The ship monitoring system 100 is a system that is installed on a ship and monitors ships in the vicinity.

The ship on which the ship monitoring system 100 is installed is an example of a first ship, and will be referred to as the "own ship" in the following explanation. The ships present around the own ship are examples of second ships, and will be referred to as the "other ships" in the following explanation.

In addition, in the following explanation, "speed" is a vector quantity that represents speed and direction (the so-called ship speed vector), and "speed" is a scalar quantity.

The ship 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.

The information processing device 1 is a computer including a CPU, RAM, ROM, non-volatile memory, an input/output interface, etc. The CPU of the information processing device 1 executes information processing according to a program loaded from the ROM or non-volatile memory to the RAM.

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

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, without being limited to a touch sensor.

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 represents the target's position and speed.

The AIS (Automatic Identification System) 4 receives AIS data from other ships around the ship or from land-based control. It is not limited to AIS, and VDES (VHF Data Exchange System) may also be used. AIS data includes the position and speed of other ships, etc.

The GNSS receiver 5 detects the ship's position based on radio waves received from the Global Navigation Satellite System (GNSS). The gyrocompass 6 detects the ship's heading. It is not limited to a gyrocompass, but a GPS compass or a magnetic compass may also be used.

The 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.

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

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 ECDIS 7. In other words, the functional parts of the information processing device 1 may be realized by another device such as ECDIS 7.

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

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 representing 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 the change in the ship's position over time.

In addition to this, the ship's speed may be detected based on the ship's direction detected by the gyrocompass 6 and the ship's speed detected by a ship speedometer (not shown).

The radar 3 or the AIS 4 is an example of a second data generating unit, and generates other ship data that indicates the position and speed of other ships. Specifically, the TT data generated by the radar 3 corresponds to the other ship data. The AIS data generated by the AIS 4 also corresponds to the other ship data.

Figure 2 is a diagram showing an example of a 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.

The other ship management database contains 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.

Figure 3 is a block diagram showing an example of the configuration of an information processing device 1 according to an embodiment. The information processing device 1 includes a risk value calculation unit 11, a front/rear passing determination 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 according to a program.

The risk value calculation unit 11 calculates a risk value representing the risk of collision between the own ship and the other ship based on the own ship data and the other ship data. Specifically, the risk value calculation unit 11 calculates a risk area in which there is a risk of collision between the own ship and the other ship, assuming that the own ship changes course in an arbitrary direction and heads toward the predicted course of the other ship.

To calculate the risk value, a known method for displaying OZT (Obstacle Zone by Target) is used. In addition to OZT, methods such as PAD (Predict Area of Danger) or DAC (Dangerous Area of Collision) may also be used. OZT, PAD, and DAC are examples of risk areas.

Figure 4 shows an example of an OZT display (conventional example). The OZT is a zone in which the ship's navigation is obstructed by other ships, and is displayed on the predicted course of the other ships.

The range GP of the other ship's predicted course where OZT is not displayed is the range in which the ship can navigate, but in such a range, it is difficult to determine at a glance whether the ship will pass in front of or behind the other ship.

In this embodiment, the forward/backward passing determination unit 12 and the display control unit 13 function to determine and display whether the ship is passing in front of or behind another ship. The specific method is described below.

Figure 5 is a diagram showing an example of the procedure of a ship monitoring method according to an embodiment, which is realized in the ship monitoring system 100. The information processing device 1 executes the information processing shown in the figure according to a program. Figure 6 is a diagram for explaining the calculation.

First, the information processing device 1 sets multiple judgment points on the predicted course of the other ship (S11). The predicted course of the other ship is the course that the other ship will take when it is assumed that the other ship will navigate from its current position while maintaining its speed. The multiple judgment points are set at equal intervals on the predicted course of the other ship.

Next, the information processing device 1 calculates a risk value representing the risk of collision between the ship and another ship at one selected judgment point from among the multiple judgment points (S12: processing as the risk value calculation unit 11).

The risk value at a decision point is expressed as the probability that your ship and the other ship will be at the decision point at the same time, assuming that your ship maintains its speed while altering course from its current position to reach the decision point, and that the other ship maintains its speed from its current position to reach the decision point.

Next, the information processing device 1 determines whether the risk value calculated in S12 is greater than or equal to a threshold value (S13).

If the risk value is greater than or equal to the threshold (S13: YES), the information processing device 1 sets the judgment point as the "OZT display point" (S14).

Next, the information processing device 1 determines whether the own ship or the other ship will reach the judgment point first (S15: processing as the forward/backward passing determination unit 12). In other words, the information processing device 1 determines whether the own ship will reach the judgment point first.

When the information processing device 1 determines that the own ship will reach the judgment point before the other ship (S15: YES), it sets the judgment point as a "passing point ahead of the other ship" where the own ship passes in front of the other ship (S16A), and when it determines that the other ship will reach the judgment point before the own ship (S15: NO), it sets the judgment point as a "passing point behind the other ship" where the own ship passes behind the other ship (S16B). In other words, the information processing device 1 determines whether the own ship will pass in front of or behind the other ship.

Specifically, the information processing device 1 calculates the probability that the own ship will arrive at the judgment point first and the probability that the other ship will arrive first, and determines which of the two calculated probabilities is larger. For example, if the probability that the own ship will arrive first is greater than the probability that the other ship will arrive first, the judgment point is determined to be the "passing point ahead of the other ship." On the other hand, if the probability that the own ship will arrive first is smaller than the probability that the other ship will arrive first, the judgment point is determined to be the "passing point behind the other ship."

The method for calculating the probability that the ship will arrive at the decision point first and the probability that another ship will arrive at the decision point first can be realized by applying the OZT calculation method in S12 above.

Without being limited to this, the information processing device 1 may calculate the time when the own ship arrives at the judgment point and the time when the other ship arrives, and determine which of the two calculated times is longer. For example, if the time when the own ship arrives is shorter than the time when the other ship arrives, the judgment point is set as the "passing point ahead of the other ship". On the other hand, if the time when the own ship arrives is longer than the time when the other ship arrives, the judgment point is set as the "passing point behind the other ship".

The information processing device 1 may also calculate the BCR (Bow Crossing Range) assuming that the ship is heading towards the judgment point, and determine whether the BCR is positive or negative. The BCR is the predicted distance from the ship to the other ship when the other ship crosses the ship's bow line. For example, if the BCR is negative, the judgment point is set to the "passing point ahead of the other ship." On the other hand, if the BCR is positive, the judgment point is set to the "passing point behind the other ship."

The methods for calculating time and BCR do not involve probability calculations, which makes it possible to reduce the computational load.

The information processing device 1 executes the processes S12 to S16 described above for all judgment points (S17).

Here, if adjacent judgment points are the same "passing point ahead of the other ship", the area between them becomes the "passing range ahead of the other ship". Similarly, if adjacent judgment points are the same "passing point behind the other ship", the area between them becomes the "passing range behind the other ship".

Next, the information processing device 1 generates an image for display and outputs it to the display unit 2 (S18: processing as the display control unit 13).

Figure 7 is a diagram showing an example of a display image displayed on the display unit 2. In the display image, OZT, which indicates that the risk value of collision between the own ship and the other ship is above a threshold, is displayed on the predicted course of the other ship. Furthermore, the "passing range ahead of the other ship" where the own ship will pass in front of the other ship and the "passing range behind the other ship" where the own ship will pass behind the other ship are displayed on the predicted course of the other ship. The predicted course of the other ship is displayed with an auxiliary line, for example a dashed line.

The forward passing range of the other ship and the rear passing range of the other ship are displayed in different display formats, such as color or texture, so that they can be easily distinguished at a glance. Furthermore, text may be added to the "forward passing range of the other ship" and the "rear passing range of the other ship" to make them easier to distinguish.

The forward passing range and rear passing range of the other ship have a predetermined width and are formed in a band extending along the predicted course of the other ship. The width of the forward passing range and rear passing range of the other ship is narrower than the width of the OZT.

At least one of the forward passing range of the other ship and the rear passing range of the other ship is displayed superimposed on the OZT. For example, the forward passing range of the other ship and the rear passing range of the other ship may be placed on the OZT, or may be placed under a translucent OZT.

According to the embodiment described above, the "passing range ahead of the other ship" and the "passing range behind the other ship" are displayed on the predicted course of the other ship, making it easy to see at a glance whether your ship will pass ahead or behind the other ship.

Figure 8 shows an example of a display image that displays DAC instead of OZT. As with the example of Figure 7 above, at least one of the forward passing range of the other ship and the rear passing range of the other ship is displayed superimposed on the DAC. For example, the forward passing range of the other ship and the rear passing range of the other ship may be placed on the DAC, or may be placed under a translucent DAC.

In the examples of Figures 7 and 8, the forward passing range and rear passing range of other ships are displayed superimposed on the risk area of the OZT or DAC, etc., so that even inside the risk area, it is possible to determine whether the ship will pass in front of or behind the other ship. This type of display is useful when it is unavoidable to take a course that enters a risk area.

As shown in FIG. 9, the forward passing range and rear passing range of other ships may be displayed only within risk areas such as OZT or DAC of the predicted course of other ships. This makes it possible to prevent visibility from being hindered by the forward passing range and rear passing range of other ships even if there are a large number of ships. In addition, the calculation load can be reduced because only the risk areas need to be judged.

As shown in FIG. 10, when displaying the forward passing range and rear passing range of other ships, the predicted course of the other ship may be displayed with an auxiliary line, such as a dashed line. This makes it easier to visually determine which other ship the forward passing range and rear passing range of other ships relate to when there are multiple other ships.

In addition, it is not necessary to display auxiliary lines beyond the forward passing range or rear passing range of the other ship that is at the very end of the other ship's predicted course in the course direction. In the example of Figure 10, the rear passing range of the other ship is at the very end of the other ship's course direction (far left in the figure), and auxiliary lines are not displayed beyond that. This makes it possible to prevent auxiliary lines from impeding visibility.

Although the embodiments of the present invention have been described above, the present invention is not limited to the above-described embodiments, and various modifications are possible for those skilled in the art.

Reference Signs List 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 Front/rear passing determination unit, 13 Display control unit, 100 Ship monitoring system

Claims (16)

a first data generation unit that generates first vessel data representing a position and a velocity of the first vessel;
a second data generation unit that generates second vessel data representing a position and a velocity of the second vessel;
a passing determination unit that determines, for each point on a predicted course of the second vessel, whether the first vessel will pass in front of or behind the second vessel, when it is assumed that the first vessel will change course and reach each point, based on the first vessel data and the second vessel data;
a display unit that displays a forward passing range in which the first vessel passes in front of the second vessel and a rear passing range in which the first vessel passes behind the second vessel on a predicted course of the second vessel;
Equipped with
a risk value calculation unit that calculates a risk area in which there is a risk of collision between the first vessel and the second vessel when it is assumed that the first vessel changes course in an arbitrary direction and heads toward a predicted course of the second vessel based on the first vessel data and the second vessel data,
The display unit further displays the risk area,
The display unit displays at least one of the forward passing range and the rearward passing range so as to overlap with the risk area.
Ship monitoring system. a first data generation unit that generates first vessel data representing a position and a velocity of the first vessel;
a second data generation unit that generates second vessel data representing a position and a velocity of the second vessel;
a passing determination unit that determines, for each point on a predicted course of the second vessel, whether the first vessel will pass in front of or behind the second vessel, when it is assumed that the first vessel will change course and reach each point, based on the first vessel data and the second vessel data;
a display unit that displays a forward passing range in which the first vessel passes in front of the second vessel and a rear passing range in which the first vessel passes behind the second vessel on a predicted course of the second vessel;
Equipped with
a risk value calculation unit that calculates a risk area in which there is a risk of collision between the first vessel and the second vessel when it is assumed that the first vessel changes course in an arbitrary direction and heads toward a predicted course of the second vessel, based on the first vessel data and the second vessel data;
The display unit further displays the risk area,
the display unit displays the forward passing range and the rear passing range within the risk area on the predicted course of the second vessel.
Ship monitoring system. The risk area is an OZT (Obstacle Zone by Target),
3. A vessel monitoring system according to claim 1 or 2. The risk area is a Dangerous Area of Collision (DAC),
3. A vessel monitoring system according to claim 1 or 2. the display unit displays an auxiliary line representing a predicted course of the second vessel together with the forward passing range and the rear passing range .
5. A vessel monitoring system according to any one of claims 1 to 4. the display unit does not display the auxiliary line beyond the forward passing range or the rear passing range which is at the farthest end in the course direction of the predicted course of the second vessel,
A vessel monitoring system according to claim 5. the passing determination unit calculates a probability that the first vessel will arrive at each of the points first and a probability that the second vessel will arrive at each of the points first, and determines whether the first vessel will pass in front of or behind the second vessel depending on a magnitude relationship between the probabilities.
7. A vessel monitoring system according to any one of claims 1 to 6. the passage determination unit calculates a time when the first vessel arrives at each of the points and a time when the second vessel arrives at each of the points, and determines whether the first vessel will pass in front of or behind the second vessel depending on a magnitude relationship between the times.
7. A vessel monitoring system according to any one of claims 1 to 6. the passage determination unit calculates a Bow Crossing Range (BCR) at each point, and determines whether the first vessel will pass in front of or behind the second vessel depending on whether the BCR is positive or negative.
7. A vessel monitoring system according to any one of claims 1 to 6. The first data generation unit is installed on the first ship and includes a GNSS receiver that detects the position of the first ship based on radio waves received from a Global Navigation Satellite System (GNSS).
10. A vessel monitoring system according to any one of claims 1 to 9. 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.
A vessel monitoring system according to any one of claims 1 to 10. A first data generation unit generates first ship data representing a position and a velocity of the first ship;
A second data generation unit generates second ship data representing a position and a velocity of the second ship;
determining, for each point on the predicted course of the second vessel, whether the first vessel will pass in front of or behind 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 forward passing range in which the first vessel passes in front of the second vessel and a rear passing range in which the first vessel passes behind the second vessel are displayed on a predicted course of the second vessel.
A vessel monitoring method, comprising:
Further, a risk area in which there is a risk of collision between the first vessel and the second vessel, assuming that the first vessel changes course in an arbitrary direction and heads toward the predicted course of the second vessel, is calculated based on the first vessel data and the second vessel data;
the display further indicates the risk area;
The display displays at least one of the forward passing range and the rearward passing range so as to overlap with the risk area.
Ship monitoring methods. A first data generation unit generates first ship data representing a position and a velocity of the first ship;
A second data generation unit generates second ship data representing a position and a velocity of the second ship;
determining, for each point on the predicted course of the second vessel, whether the first vessel will pass in front of or behind 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 forward passing range in which the first vessel passes in front of the second vessel and a rear passing range in which the first vessel passes behind the second vessel are displayed on a predicted course of the second vessel.
A vessel monitoring method, comprising:
Further, a risk area in which there is a risk of collision between the first vessel and the second vessel, assuming that the first vessel changes course in an arbitrary direction and heads toward the predicted course of the second vessel, is calculated based on the first vessel data and the second vessel data;
the display further indicates the risk area;
the display displays the forward passing range and the rear passing range within the risk area on the predicted course of the second vessel.
Ship monitoring methods. a passing determination unit that determines, for each point on a predicted course of the second ship, whether the first ship will pass in front of or behind the second ship, when it is assumed that the first ship will change course and reach each point, based on first ship data indicating the position and speed of the first ship and second ship data indicating the position and speed of the second ship;
a display control unit that generates a display image for displaying a forward passing range in which the first vessel passes in front of the second vessel and a rear passing range in which the first vessel passes behind the second vessel on a predicted course of the second vessel; and
Equipped with
a risk value calculation unit that calculates a risk area in which there is a risk of collision between the first vessel and the second vessel when it is assumed that the first vessel changes course in an arbitrary direction and heads toward a predicted course of the second vessel based on the first vessel data and the second vessel data,
The display control unit further displays the risk area,
The display control unit displays at least one of the forward passing range and the rear passing range so as to overlap with the risk area.
Information processing device. determining, for each point on a predicted course of the second vessel, whether the first vessel will pass in front of or behind the second vessel when it is assumed that the first vessel will change course and reach each point, based on first vessel data representing a position and speed of the first vessel and second vessel data representing a position and speed of the second vessel; and
generating a display image for displaying a forward passing range in which the first vessel passes in front of the second vessel and a rear passing range in which the first vessel passes behind the second vessel on a predicted course of the second vessel;
on the computer,
Furthermore, the method executes a calculation of a risk area in which there is a risk of collision between the first vessel and the second vessel when it is assumed that the first vessel changes course in an arbitrary direction and heads toward the predicted course of the second vessel, based on the first vessel data and the second vessel data,
the display image further displays the risk area;
The display image displays at least one of the forward passing range and the rearward passing range superimposed on the risk area.
program. determining, for each point on a predicted course of the second vessel, whether the first vessel will pass in front of or behind the second vessel when it is assumed that the first vessel will change course and reach each point, based on first vessel data representing a position and speed of the first vessel and second vessel data representing a position and speed of the second vessel; and
generating a display image for displaying a forward passing range in which the first vessel passes in front of the second vessel and a rear passing range in which the first vessel passes behind the second vessel on a predicted course of the second vessel;
on the computer,
Furthermore, the method executes a calculation of a risk area in which there is a risk of collision between the first vessel and the second vessel when it is assumed that the first vessel changes course in an arbitrary direction and heads toward the predicted course of the second vessel, based on the first vessel data and the second vessel data,
the display image further displays the risk area;
the display image displays the forward passing range and the rear passing range within the risk area on the predicted course of the second vessel,
program.

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