WO2023008360A1

WO2023008360A1 - Navigation assistance system, terminal device, and boat

Info

Publication number: WO2023008360A1
Application number: PCT/JP2022/028588
Authority: WO
Inventors: 滋黒井
Original assignee: 日本発條株式会社
Priority date: 2021-07-26
Filing date: 2022-07-25
Publication date: 2023-02-02
Also published as: JP2023017303A

Abstract

A navigation assistance system according to an embodiment comprises a plurality of terminal devices onboard a plurality of boats, respectively. Each of the plurality of terminal devices comprises: a display; a positioning unit that detects location information about its own boat; a communication unit that transmits the location information detected by the positioning unit to other boats and also receives location information about other boats; and a controller that displays, on the display, the locations of other boats indicated by the location information received by the communication unit and issues a warning if the distance between the own boat and another boat equals or exceeds a first threshold value.

Description

Navigation support system, terminal equipment and craft

The present invention relates to a navigation support system that supports navigation by a plurality of boats, a terminal device that configures the system, and a boat that includes the terminal device.

Conventionally, when multiple boats such as personal watercraft and small boats sail in a group, the operator of each boat visually checks the surroundings and confirms the position of the other boats. Boats are sometimes provided with rearview mirrors and rearview monitors, and in this case, it is possible to check the boat behind them through the rearview mirrors.

Because the sea is wide, other boats may sail not only in front of and behind your boat like on roads, but also far to the left and right of your boat. Therefore, there is a limit to grasping the position of other boats by visual observation. In addition, when the operator turns backward, he/she takes his/her eyes away from the traveling direction of the own boat, which is both inconvenient and potentially dangerous.

When using the rearview mirror, it is difficult to check the situation behind due to the narrow field of view, and when using the rearview monitor, it is difficult to check the boats scattered over a wide area on the screen.

JP 2020-152179 A

One of the purposes of the present invention is to support navigation by multiple boats and realize safe navigation.

A navigation support system according to one embodiment includes a plurality of terminal devices each mounted on a plurality of boats. Each of the plurality of terminal devices includes a display, a positioning unit that detects the position information of the own boat, and a communication unit that transmits the position information detected by the positioning unit to other boats and receives the position information of the other boats. and a controller that displays the position of the other boat indicated by the position information received by the communication unit on the display, and issues a warning when the distance between the own boat and the other boat is equal to or greater than a first threshold. ing.

Further, the controller determines that the distance between the own boat and the other boat is equal to or greater than a second threshold smaller than the first threshold and less than the first threshold, and the traveling direction of the other boat is the same as the traveling direction of the own boat. A warning may be issued in different cases.

Further, the controller may issue a warning when the distance between the own boat and the other boat is less than a third threshold that is smaller than the second threshold.

Furthermore, when another boat is positioned to the side of the own boat, the controller issues a warning if the direction of travel of the other boat is different from the direction of travel of the own boat. If it matches the direction, it is not necessary to issue a warning.

Furthermore, the controller may set the other boat whose position is to be displayed on the display by performing pairing with the terminal device of the other boat.

According to the present invention, it is possible to support navigation by a plurality of boats and realize safe navigation.

FIG. 1 is a diagram illustrating an example of a navigation support system according to one embodiment. FIG. 2 is a diagram illustrating a configuration example of a terminal device according to one embodiment. FIG. 3 is a diagram illustrating an example of a navigation screen according to one embodiment. FIG. 4 is a flowchart illustrating an example of the operation of a controller according to one embodiment; FIG. 5 is a diagram for explaining a specific example of warning processing according to one embodiment. FIG. 6 is a diagram showing another example of warning processing.

An embodiment will be described with reference to the drawings.
FIG. 1 is a diagram showing an example of a navigation support system 1 according to this embodiment. The navigation support system 1 includes a plurality of terminal devices 3 mounted on a plurality of boats 2, respectively.

The watercraft 2 are small vessels such as personal watercraft, pleasure boats and yachts, but may be larger vessels. The terminal devices 3 of the watercraft 2 are capable of wireless communication with each other.

In the example of FIG. 1, five

boats

2A, 2B, 2C, 2D and 2E and

terminal devices

3A, 3B, 3C, 3D and 3E mounted on these boats are shown. However, the navigation support system 1 may be composed of terminal devices 3 mounted on four or less or six or more boats 2 .

FIG. 2 is a diagram showing a configuration example of the terminal device 3 (3A, 3B, 3C, 3D, 3E). The terminal device 3 includes a display 4 , a speaker 5 , an input unit 6 , a positioning unit 7 , a communication unit 8 and a controller 9 .

The display 4 is provided at a position where the operator looking ahead of the boat 2 can easily visually recognize it, and can display various images for the operator. The speaker 5 can output messages, warning sounds, and the like directed to the operator. The input unit 6 is, for example, a touch panel provided on the display 4 , but may be a button or the like independent of the display 4 .

The positioning unit 7 detects the position information of the boat 2 (own boat) on which the positioning unit 7 is mounted. For example, the positioning unit 7 has an antenna for receiving signals from satellites that constitute a satellite positioning system such as GPS (Global Positioning System), and detects the position information of the boat 2 based on the signals received by the antenna. Furthermore, the positioning unit 7 may include an orientation sensor that detects orientation information indicating the direction in which the bow of the boat 2 is currently facing.

The communication unit 8 wirelessly transmits and receives information to and from the communication unit 8 of another boat 2 (another boat). The wireless communication protocol of the communication unit 8 is not particularly limited, but Wi-Fi (registered trademark) or BLE (registered trademark) can be used as an example.

The controller 9 includes a processor 90 and a memory 91, for example. In this embodiment, the processor 90 executes a computer program to realize various processes including control of the display 4, the speaker 5, the input unit 6, the positioning unit 7 and the communication unit 8. FIG. However, the processes exemplified as those executed by the controller 9 in this embodiment may be distributed and executed by a plurality of processors.

The memory 91 stores various data necessary for controlling the terminal device 3 . These data include a pairing table 92 in which identification information and the like of boats 2 (terminal devices 3) forming a group that monitor each other's positions is written.

All the elements that make up the terminal device 3 do not necessarily have to be fixedly provided with respect to the boat 2 . For example, at least part of the terminal device 3 may be realized by a portable device such as a smart phone. In this case, the boat 2 may be provided with a mechanism for attaching the portable device.

Further, for example, when the communication unit 8 is built in the portable device, if the wireless communication range is narrow, a repeater for relaying the communication between the communication unit 8 and the communication unit 8 of another boat It may be provided in the boat 2 .

In order to start sailing, pairing of the boats 2 that make up the group is first performed. This pairing is started in response to an instruction to execute pairing by operating the input unit 6, for example.

For example, in the terminal device 3 that started pairing, the communication unit 8 continuously transmits a signal containing the identification information of the own boat and receives a similar signal transmitted from the communication unit 8 of another boat. When receiving a signal transmitted from the communication unit 8 of another boat, the controller 9 writes the identification information of the other boat included in the signal into the pairing table 92 . For example, in the group configuration of FIG. 1, the identification information of the

boats

2B, 2C, 2D, and 2E is written in the pairing table 92 of the terminal device 3A. Similarly, the identification information of other boats is written in the pairing tables 92 of the

terminal devices

3B, 3C, 3D and 3E. When the terminal device 3 is a portable device such as a smart phone, the boat 2 on which the terminal device 3 is mounted and the terminal device 3 are paired, whereby the terminal device 3 receives the identification information of the boat 2. may be obtained. This pairing may be performed automatically, for example, when the terminal device 3 is attached to the watercraft 2, or may be performed manually by the operator operating the terminal device 3.

The pairing method is not limited to this example. For example, the identification information of the other boat may be written into the pairing table 92 by operating the input unit 6 . Also, the pairing table 92 in which the identification information of other boats is written in advance may be input to the terminal device 3 via the communication unit 8 or the like and stored in the memory 91 .

After pairing, in the terminal device 3 of each boat, the positioning unit 7 detects the position information of the own boat. Furthermore, the communication unit 8 transmits the position information and the identification information of its own boat to the other boats whose identification information is written in the pairing table 92, and receives the position information and the identification information transmitted from these other boats. The detection of the positional information of the own boat, the transmission of the positional information, and the reception of the positional information of the other boats are repeatedly executed during navigation.

The controller 9 of each boat displays a navigation screen 10 showing the real-time positions of the own boat and each other boat on the display 4 based on the position information of the own boat and each other paired boat.

FIG. 3 is a diagram showing an example of the navigation screen 10. FIG. The navigation screen 10 is displayed on the display 4 of the boat 2A, and includes a boat figure 11A imitating the boat 2A (own boat) and boat figures imitating the

boats

2B, 2C, 2D, and 2E (other boats). 11B, 11C, 11D, and 11E.

The boat graphic 11A of the own boat is positioned, for example, in the center of the navigation screen 10, but is not limited to this example. The boat figure 11A of the own boat and the boat figures 11B, 11C, 11D, and 11E of the other boats are displayed in a manner distinguishable from each other, for example, by using different colors or shapes.

The boat figures 11A, 11B, 11C, 11D, and 11E have shapes that can identify the direction of travel of the

boats

2A, 2B, 2C, 2D, and 2E, respectively. In the example of FIG. 3, boat figures 11A, 11B, 11C, 11D, and 11E have elongated shapes with one end pointed and the other end flat. This pointed end represents the bow, and the direction in which the end is pointed corresponds to the direction of travel.

For example, based on the boat graphic 11A, it can be seen that the boat 2A is traveling upward on the navigation screen 10 in the traveling direction XA. Further, for example, based on the boat graphic 11B, it can be seen that the boat 2B is traveling in a direction that intersects the traveling direction XA of the own boat, such as the traveling direction XB.

The boat graphic 11A of the own boat may be fixedly arranged so that the traveling direction XA always faces upward on the navigation screen 10. This makes it easier for the operator viewing the navigation screen 10 to intuitively grasp the traveling direction of each boat relative to the own boat. As another example, the own boat figure 11A and the other boat figures 11B, 11C, 11D, and 11E may be arranged such that a specific direction such as north always faces upward.

The boat figures 11A, 11B, 11C, 11D, and 11E may have shapes different from those illustrated, such as arrows pointing in the direction of travel of each boat.

The speed of each boat may also be displayed on the navigation screen 10. The speed may be indicated numerically, or may be indicated by a method such as color-coding the boat figures 11A, 11B, 11C, 11D, and 11E according to the speed of each boat. The speed of each boat can be calculated based on the time-series positional information of each boat. As another example, each boat may detect its own speed and transmit it to the other boats via the communication unit 8 .

Next, a specific example of processing executed by the controller 9 will be described.
FIG. 4 is a flow chart showing an example of the operation of the controller 9. As shown in FIG. The processing shown in the flowchart is processing that is executed for another boat when position information is received from the other boat. The processing shown in the flowchart is repeatedly executed for each boat each time position information is received from each boat.

First, the controller 9 identifies the traveling direction of the other boat based on the position information received from the other boat (step S1). The direction of travel of another boat can be identified based on the chronological positional information of the other boat. For example, if the position indicated by the latest position information received from another boat is set as the first position, and the position indicated by the position information of the other boat received at least one position before the latest position information is set as the second position. , the controller 9 identifies the direction from the second position to the first position as the traveling direction of the other boat. However, the method of identifying the traveling direction is not limited to this example. For example, if the positioning unit 7 of each watercraft 2 is equipped with the above-described azimuth sensor, the information transmitted and received between the watercraft 2 includes azimuth information, and the controller 9 identifies the traveling direction of the other boat based on this azimuth information. may

The controller 9 updates the boat figure of the other boat on the navigation screen 10 (step S2). Specifically, the controller 9 displays the boat graphic facing the traveling direction specified in step S1 at the position indicated by the latest position information received from the other boat.

Subsequently, the controller 9 calculates the distance D between the position indicated by the latest position information received from the other boat and the position of the own boat indicated by the position information detected by the positioning unit 7 of the own boat ( step S3).

The controller 9 uses the calculated distance D to execute a warning process regarding navigation safety (steps S4 to S11). In this embodiment, the first threshold D1, the second threshold D2 and the third threshold D3 are used in the warning process.

The second threshold D2 is smaller than the first threshold D1, and the third threshold D3 is smaller than the second threshold D2. That is, D1>D2>D3 is established. The first threshold value D1 is a criterion for determining that the own boat is too far away from another boat, and is 100 m in one example. The third threshold D3 is a criterion for determining that the own boat and another boat are too close, and is 10 m in one example. The second threshold D2 can be set to an appropriate value between the first threshold D1 and the third threshold D3.

After calculating the distance D between the own boat and the other boat in step S3, the controller 9 determines whether the distance D is greater than or equal to the first threshold value D1 (step S4). If it is determined that the distance D is equal to or greater than the first threshold value D1 (Yes in step S4), the controller 9 warns that the other boat is too far away (step S5).

The warning in step S5 is performed by emitting a warning sound or warning message from the speaker 5, for example. As another example, the warning may be given by displaying a warning message on the navigation screen 10, changing the display color of the other boat's boat graphic, or blinking the other boat's boat graphic. Alternatively, the warning may be issued by transmitting warning information to the other boat through the communication unit 8 . In this case, the controller 9 of the other boat that has received the warning information warns the operator of the other boat using at least one of the display 4 and the speaker 5, for example.

If it is determined in step S4 that the distance D is not greater than or equal to the first threshold value D1 (No in step S4), the controller 9 determines whether or not the distance D is greater than or equal to the second threshold value D2 and less than the first threshold value D1 (step S6 ).

Further, when it is determined that the distance D is equal to or greater than the second threshold value D2 and less than the first threshold value D1 (Yes in step S6), the controller 9 determines that the traveling direction of the other boat identified in step S1 is the traveling direction of the own boat. (step S7). The direction of travel of the own boat can be specified based on the time-series positional information detected by the positioning unit 7 of the own boat, in the same way as the direction of travel of the other boat is specified in step S1.

When it is determined that the traveling direction of the other boat does not match the traveling direction of the own boat (No in step S7), the controller 9 issues a warning in step S5. On the other hand, if it is determined that the traveling directions match (No in step S7), the controller 9 does not issue a warning in step S5.

It should be noted that in step S7, not only when the directions of travel of the own boat and the other boat are completely the same, but also when they are slightly deviated from each other, the directions of travel may be regarded as the same. That is, the controller 9 determines that the two match when the traveling direction of the other boat is in the range of -θ or more and +θ or less with respect to the traveling direction of the own boat. θ is a threshold value of an angle at which the traveling directions can be considered to match, and can be set to a value of 10 degrees or less, for example.

If it is determined in step S6 that the distance D is not less than the second threshold value D2 and less than the first threshold value D1 (No in step S6), the controller 9 determines whether the distance D is less than the third threshold value D3 (step S8 ). If it is determined that the distance D is less than the third threshold value D3 (Yes in step S8), the controller 9 warns that the other boat is too close to the own boat (step S9). On the other hand, when determining that the distance D is not less than the third threshold value D3 (No in step S8), the controller 9 does not issue a warning in step S9.

The warning in step S9 is performed, for example, by emitting a warning sound or warning message from the speaker 5, like the warning in step S5. As another example, the warning may be given by displaying a warning message on the navigation screen 10, changing the display color of the other boat's boat graphic, or blinking the other boat's boat graphic. Alternatively, the warning may be issued by transmitting warning information to the other boat through the communication unit 8 . In this case, the controller 9 of the other boat that has received the warning information warns the operator of the other boat using at least one of the display 4 and the speaker 5, for example.

After steps S4 to S9, the controller 9 determines whether the other boat has suddenly decelerated (step S10). In this determination, for example, the acceleration of the other boat is calculated based on the time-series positional information received from the other boat, and if the acceleration is a negative value equal to or less than a predetermined threshold, the other boat suddenly It is determined that the vehicle has slowed down.

When it is determined that the other boat has suddenly decelerated (Yes in step S10), the controller 9 warns that the other boat has suddenly decelerated (step S11). After step S11, or if it is determined in step S11 that the other boat is not decelerating rapidly (No in step S10), the exemplary process of the flowchart shown in FIG. 4 ends.

The warning in step S11 is performed, for example, by emitting a warning sound or warning message from the speaker 5, like the warning in step S5. As another example, the warning may be given by displaying a warning message on the navigation screen 10, changing the display color of the other boat's boat graphic, or blinking the other boat's boat graphic. Alternatively, the warning may be issued by transmitting warning information to the other boat through the communication unit 8 . In this case, the controller 9 of the other boat that has received the warning information warns the operator of the other boat using at least one of the display 4 and the speaker 5, for example.

Note that the warnings in steps S5, S9, and S11 are preferably issued in different manners so that the operator can easily distinguish between the types of these warnings.

Instead of issuing a warning when the other boat suddenly decelerates as in steps S10 and S11, a warning may be issued to the other boat when the own boat suddenly decelerates. In this case, the determination of the sudden deceleration of the own boat may be made based on the time-series positional information of the own boat, or may be made based on the speed data output by the speedometer or the like of the own boat. .

Also, instead of issuing a warning when the other boat suddenly decelerates as in steps S10 and S11, a warning may be issued when the other boat suddenly accelerates.

FIG. 5 is a diagram for explaining a specific example of the warning process (steps S4 to S11). In this figure, boat figures 11A, 11B, 11C, 11D and 11E of

boats

2A, 2B, 2C, 2D and 2E are shown on the assumption that the boat 2A is the own boat. The first threshold D1, the second threshold D2, and the third threshold D3 can be represented by concentric circles centered on the own boat, as shown in FIG. 5, for example.

In the example of FIG. 5, the boat 2B and the boat 2A are separated by the first threshold value D1 or more (Yes in step S4). Therefore, in the processing of the above-described flowchart for the watercraft 2B, the warning of step S5 is executed. As a result, for example, the operator of the watercraft 2A can change the speed to match the speed of the watercraft 2B, thereby preventing the group from spreading widely on the water.

Also, in the example of FIG. 5, the boat 2C and the boat 2A are approaching the third threshold value D3 or less (Yes in step S8). Therefore, in the processing of the above-described flowchart for the watercraft 2C, the warning of step S9 is executed. As a result, the operator of the watercraft 2A can avoid a collision with the watercraft 2C by, for example, maintaining a distance from the watercraft 2C.

In the example of FIG. 5, the watercraft 2D indicated by the solid line is positioned in a range equal to or greater than the second threshold D2 and less than the third threshold D3 (Yes in step S6). Furthermore, the traveling direction XD matches the traveling direction XA of the watercraft 2A (Yes in step S7). Therefore, in the processing of the above-described flowchart for the watercraft 2D, the warning in step S5 is not executed.

On the other hand, although the watercraft 2D indicated by the dashed line is positioned within the range of the second threshold value D2 or more and less than the third threshold value D3 (Yes in step S6), its traveling direction XD differs from the traveling direction XA of the watercraft 2A (step S7). No). In the processing of the above-described flowchart targeting such a watercraft 2D, the warning of step S5 is executed. As a result, the operator of the watercraft 2A can know in advance that the watercraft 2D may move far away from or approach the own watercraft.

In the example of FIG. 5, the boat 2E indicated by the solid line is located in a range equal to or greater than the third threshold D3 and less than the second threshold D2. In this case, the warnings of steps S5 and S9 are not executed for the boat 2E. If the boat 2E suddenly decelerates due to some trouble as indicated by the dashed line (Yes in step S10), a warning is issued in step S11. This allows the operator of the watercraft 2A to know that trouble has occurred in the watercraft 2E.

It should be noted that the operator of each boat can also send warnings and messages to other boats by operating the input unit 6 at arbitrary timing, such as when the boat wishes to stop.

　In the examples of Figures 4 and 5, it is assumed that warnings are issued mainly based on the distance D between the own boat and the other boat. As a condition for issuing a warning, the direction of other boats relative to your own boat may also be taken into consideration, as shown below.

FIG. 6 is a diagram showing another example of warning processing. In this example, regions R1 and R2 are further set in addition to the first threshold D1, the second threshold D2 and the third threshold D3. Regions R1 and R2 are ranges that can be regarded as left and right sides of the own boat (boat 2A in the example of FIG. 6). Although the regions R1 and R2 can be determined by any suitable method, in one example, they can be defined as a range of a specific angle .theta.R between the right and left sides of the own boat as shown in the figure.

For example, in the warning process using such areas R1 and R2, the controller 9 determines that the distance D between the other boat and the own boat is greater than or equal to the second threshold value D2 and less than the first threshold value D1, and that the other boat is in the areas R1 and R2. If the boat is not located in any of R2, the warning of step S5 is issued regardless of the direction of travel of the own boat or the other boat.

Further, when the distance D is equal to or greater than the second threshold value D2 and less than the first threshold value D1, and the other boat is located in either of the regions R1 and R2, the controller 9 determines that the traveling directions of the own boat and the other boat are different. Issue a warning only if there is no match.

For example, in FIG. 6,

boats

2B, 2C, and 2D are all positioned within a range equal to or greater than the second threshold D2 and less than the first threshold D1. As for the watercraft 2B, a warning is given because the direction of travel XB of the watercraft 2B is different from the direction of travel XA of the own watercraft (the watercraft 2A). No warning is given to the watercraft 2C because its traveling direction XC matches the traveling direction XA and it is located in the area R1. On the other hand, as for the watercraft 2D, although its traveling direction XD coincides with the traveling direction XA, it is not located in either of the regions R1 and R2, so a warning is issued.

Like boat 2C, boats traveling in the same direction as own boat on the left and right of own boat, that is, boats running parallel to own boat, are less likely to get separated from own boat. Therefore, by not issuing a warning to such a boat even if it is at a certain distance, it is possible to provide more accurate navigation support.

Here, it is assumed that areas R1 and R2 are set to the left and right of the own boat, but similar areas may be set to the rear of the own boat. Also, for example, even if the distance D between the own boat and the other boat is equal to or greater than the first threshold value D1 or less than the third threshold value D3, if the other boat is located in the regions R1 and R2 and the traveling direction is the same as the own boat. You may choose not to warn

According to the present embodiment described above, it is possible to confirm the positions of other boats on the navigation screen 10 in each of the boats forming the group. Therefore, the operator can confirm the position of the other boat without overlooking the surroundings even when the other boat is positioned behind or to the left or right. In addition, even if the other boat is far away or visibility is poor, it is extremely easy to grasp the position of the other boat.

In addition, warnings are issued when your boat is too far away from another boat or when they are too close to each other, so you can avoid the danger of one of the boats getting separated from the group or the boats colliding with each other.

As a condition for issuing a warning, not only the distance D between the own boat and the other boat, but also the direction of travel between the own boat and the other boat is considered. This enables accurate warnings that match actual navigation.

The other boat whose position is to be displayed on the navigation screen 10 can be freely set by pairing. This facilitates the formation of groups for each trip.

In addition, various favorable effects can be obtained from this embodiment. According to this embodiment, there are provided a navigation support system 1, a terminal device 3, and a boat 2 that are capable of supporting navigation by a plurality of boats and realizing safe navigation.

The above embodiments do not limit the scope of the present invention to the configurations disclosed in the embodiments. The present invention can be implemented by modifying the configuration disclosed in the embodiment into various modes.

DESCRIPTION OF SYMBOLS 1... Navigation support system, 2... Boat, 3... Terminal device, 4... Display, 5... Speaker, 6... Input unit, 7... Positioning unit, 8... Communication unit, 9... Controller, 10... Navigation screen, 11... Boat figure, D1...first threshold, D2...second threshold, D3...third threshold, R1, R2...regions.

Claims

A navigation support system comprising a plurality of terminal devices respectively mounted on a plurality of boats,
Each of the plurality of terminal devices,
a display;
a positioning unit that detects the position information of the own boat;
a communication unit that transmits position information detected by the positioning unit to other boats and receives position information of other boats;
a controller that displays the position of the other boat indicated by the position information received by the communication unit on the display and issues a warning when the distance between the own boat and the other boat is equal to or greater than a first threshold;
A navigation support system.
Further, the controller determines that the distance between the own boat and the other boat is equal to or greater than a second threshold smaller than the first threshold and less than the first threshold, and the traveling direction of the other boat is the same as the traveling direction of the own boat. warn if different,
The navigation support system according to claim 1.
Further, the controller issues a warning when the distance between the own boat and the other boat is less than a third threshold that is smaller than the second threshold.
The navigation support system according to claim 2.
Furthermore, when another boat is positioned to the side of the own boat, the controller issues a warning if the direction of travel of the other boat is different from the direction of travel of the own boat. No warning if direction matches,
The navigation support system according to claim 1.
Further, the controller sets the other boat whose position is to be displayed on the display by performing pairing with the terminal device of the other boat.
The navigation support system according to any one of claims 1 to 4.
A terminal device mounted on a boat,
a display;
a positioning unit that detects the position information of the own boat;
a communication unit that transmits position information detected by the positioning unit to other boats and receives position information of other boats;
a controller that displays the position of the other boat indicated by the position information received by the communication unit on the display and issues a warning when the distance between the own boat and the other boat is equal to or greater than a first threshold;
terminal device.
Further, the controller determines that the distance between the own boat and the other boat is equal to or greater than a second threshold smaller than the first threshold and less than the first threshold, and the traveling direction of the other boat is the same as the traveling direction of the own boat. warn if different,
The terminal device according to claim 6.
Further, the controller issues a warning when the distance between the own boat and the other boat is less than a third threshold that is smaller than the second threshold.
The terminal device according to claim 7.
Furthermore, when another boat is positioned to the side of the own boat, the controller issues a warning if the direction of travel of the other boat is different from the direction of travel of the own boat. No warning if direction matches,
The terminal device according to claim 6.
A boat comprising the terminal device according to any one of claims 6 to 9.