Set net monitoring system, set net monitoring method and program

Abstract

To provide a fixed net monitoring system, a method for monitoring a fixed net, and a program for acquiring the depth of the bottom of a fixed net and monitoring the state of the fixed net.SOLUTION: A fixed net monitoring system 1 includes: a sending-receiving unit 22b for sending a sound wave to the bottom of a fixed net set in water, receiving a reflection wave of the sound wave, and outputting an echo signal; a net bottom depth calculation unit 41a for calculating the depth of the fixed net on the basis of the echo signal; a notification information generation unit 41b for generating notification information on the basis of the result of calculating the depth of the bottom; and a transmission processing unit 41c for sending the notification information to a terminal device 50 through an external communication net 32.SELECTED DRAWING: Figure 3

Description

[Technical Field]

[0001] The present invention relates to a set net monitoring system, a set net monitoring method, and a program for monitoring a set net. [Background technology]

[0002] Conventionally, there are known devices that use underwater detection devices to monitor the shape of nets. Patent Document 1 describes a device that determines the longitudinal cross-sectional shape at each rotation angle of an ultrasonic transducer, calculates the volume of the aquaculture net by integrating the areas of the cross-sectional shapes at each rotation angle, and issues an alarm when the cross-sectional shape is deformed beyond a specified value or when the volume falls below a predetermined value. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Publication No. 4-331394 Summary of the Invention [Problem to be solved by the invention]

[0004] In the operation of set nets, users monitor the condition of the set net by determining the depth themselves by referring to echograms from fish finders, etc. However, this monitoring method places a heavy burden on users.

[0005] In view of the above problems, the present invention aims to provide a set net monitoring system, a set net monitoring method, and a program that are capable of acquiring the depth of the bottom of a set net and monitoring the state of the set net. [Means for solving the problem]

[0006] A first aspect of the present invention relates to a set net monitoring system, which includes a wave transmitting / receiving unit that transmits sound waves toward the bottom of a set net installed underwater, receives the reflected waves of the sound waves, and outputs an echo signal, a net bottom depth calculating unit that calculates the depth of the bottom of the set net based on the echo signal, a report information generating unit that generates report information based on the calculation result of the bottom depth, and a transmission processing unit that transmits the report information to a terminal device via an external communication network. The net bottom depth calculation unit acquires the calculation result of the current bottom depth as the depth of the bottom of the fixed net when it is possible to adopt the depth of the bottom of the fixed net calculated by the current transmission of the sound waves based on the echo signals obtained by each of the previous transmissions of the sound waves.

[0007] According to the set net monitoring system of this aspect, notification information regarding the depth of the bottom of the set net can be output via a terminal device, allowing a user of the notification information to monitor the condition of the bottom of the set net and determine whether or not to proceed with fishing by sailing a boat into the set net.

[0008] A second aspect of the present invention relates to a set net monitoring method, which includes calculating the depth of the bottom of a set net based on an echo signal corresponding to a reflected wave of a sound wave transmitted toward the bottom of the set net installed underwater, generating notification information based on the calculation result of the bottom depth, and transmitting the notification information to a terminal device via an external communication network. When calculating the depth of the bottom of the fixed net, if it is possible to adopt the depth of the bottom of the fixed net calculated by the current transmission of the sound waves based on the echo signals obtained by each of the previous transmissions of the sound waves up to a predetermined number of times before this transmission, the calculation result of the current depth of the bottom is obtained as the depth of the bottom of the fixed net.

[0009] According to the set net monitoring method of this aspect, the same effects as those of the first aspect can be achieved.

[0010] A third aspect of the present invention is The fixed net monitoring system of the first aspect; External communication network Communicate via The program according to this aspect causes a control unit of a terminal device to execute a predetermined function via the external communication network. The fixed net monitoring system from The aforementioned The terminal device includes a function for receiving notification information and a function for displaying the notification information on a display unit of the terminal device.

[0011] According to the program of this aspect, the terminal device can output notification information about the depth of the bottom of the set net, allowing a user of the notification information to monitor the condition of the bottom of the set net and determine whether to proceed with fishing by sailing a boat into the set net. [Effects of the Invention]

[0012] As described above, according to the present invention, it is possible to provide a set net monitoring system, a set net monitoring method, and a program that are capable of acquiring the depth of the bottom of a set net and monitoring the state of the set net.

[0013] The effects and significance of the present invention will become more apparent from the following description of the embodiments, however, the embodiments shown below are merely examples of how the present invention can be implemented, and the present invention is not limited to the embodiments described below. [Brief explanation of the drawings]

[0014] [Figure 1] FIG. 1 is a perspective view showing a usage form of a set net installed on the sea and an offshore unit installed in the set net according to an embodiment. [Figure 2] FIG. 2 is a schematic diagram showing the configuration of a set net monitoring system according to an embodiment. [Figure 3] FIG. 3 is a block diagram showing the configuration of a fixed net monitoring system according to an embodiment. [Figure 4] FIG. 4 is a diagram schematically illustrating the configuration of a transmission packet transmitted by a control unit according to the embodiment. [Figure 5] 5(a) to 5(c) are diagrams each schematically showing the configuration of a network database, a time-series database, and a user database according to an embodiment. [Figure 6] FIG. 6 is a flowchart showing the processing of the offshore unit and the server according to the embodiment. [Figure 7] FIG. 7 is a flowchart showing a net bottom depth calculation process according to the embodiment. [Figure 8] FIG. 8 is a diagram illustrating the echo signals of each line as time passes from line n to line n+6 according to the embodiment. [Figure 9]FIG. 9 is a flowchart showing the processing of the server and the terminal device according to the embodiment. [Figure 10] FIG. 10 is a diagram schematically illustrating the configuration of the notification information according to the embodiment. [Figure 11] FIG. 11 is a diagram schematically illustrating a screen displayed on a display input unit according to the embodiment. [Figure 12] FIG. 12 is a flowchart showing a process for transmitting other notification information according to the first modification. [Figure 13] 13(a) to 13(c) are diagrams showing the relationship between time and net bottom depth according to the first modified example. [Figure 14] FIG. 14 is a block diagram showing the configuration of an offshore unit according to the second modification. [Figure 15] FIG. 15 is a diagram schematically showing the configuration of notification information according to the second modification. [Figure 16] FIG. 16 is a diagram schematically showing a screen displayed on a display input unit according to the second modification. [Figure 17] FIG. 17 is a block diagram showing the configuration of a fixed net monitoring system according to a modified example in which the net bottom depth calculation unit is provided in the offshore unit. [Figure 18] FIG. 18 is a flowchart showing the processing of the offshore unit and the server in a modified example in which the net bottom depth calculation unit is provided in the offshore unit. DETAILED DESCRIPTION OF THE INVENTION

[0015] Hereinafter, an embodiment of the present invention will be described with reference to the drawings.

[0016] FIG. 1 is a perspective view showing a manner in which a fixed net 10 installed on the sea and an offshore unit 20 installed on the fixed net 10 are used.

[0017] The fixed net 10 includes a fence net 11, a fencing net 12, a climbing net 13, and a main net 14.

[0018] The fence net 11 is a net that extends in a straight line from the entrance of the enclosure net 12 outward so as to guide the school of fish into the enclosure net 12. The enclosure net 12 is a net that surrounds the inside to prevent the escape of the school of fish guided by the fence net 11. The ascending net 13 guides the school of fish inside the enclosure net 12 to the main net 14 and has a sloped shape to prevent the school of fish from moving from the main net 14 to the enclosure net 12. The main net 14 is a net that ultimately captures the school of fish. The main net 14 is sometimes called a box net. The offshore unit 20 is held to the main net 14 by a string so that it is positioned near the top center of the main net 14 in a plan view.

[0019] FIG. 2 is a schematic diagram showing the configuration of the set net monitoring system 1. As shown in FIG.

[0020] The fixed net monitoring system 1 includes an offshore unit 20, a server 40, and a terminal device 50.

[0021] The offshore unit 20 is positioned near the water surface of the main net 14. The offshore unit 20 detects the fish schools and the bottom 14a in the main net 14 by transmitting ultrasonic waves toward the seabed and receiving ultrasonic waves returning from the seabed. The offshore unit 20 also detects the position of the fixed net 10 based on GPS.

[0022] The offshore unit 20 is connected to an external communication network 32 via a base station 31 installed on the land side (ground side) so as to be able to communicate with the external communication network 32. The offshore unit 20 transmits transmission packets, which will be described later with reference to Figure 4, to the server 40 via the base station 31 and the external communication network 32.

[0023] The server 40 is installed on the land side (ground side) and is connected to the external communication network 32 so as to be able to communicate with the external communication network 32. The server 40 receives transmission packets from the offshore units 20 via the base station 31 and the external communication network 32, and stores information in the received transmission packets. When the server 40 receives a request from a terminal device 50, it generates broadcast information based on the information in the transmission packets and transmits the generated broadcast information to the corresponding terminal device 50. The broadcast information will be described later with reference to FIG. 10.

[0024] The terminal device 50 is an information terminal device such as a smartphone or a tablet, and is connected to the external communication network 32 via a wireless router 33, a base station 34, etc. so as to be able to communicate with the external communication network 32. The terminal device 50 receives notification information from the server 40 via the external communication network 32 and the wireless router 33 or the base station 34, and displays the received notification information.

[0025] FIG. 3 is a block diagram showing the configuration of the fixed net monitoring system 1. As shown in FIG.

[0026] The offshore unit 20 includes a control unit 21, a target detector 22, a position detection unit 23, and a communication unit 24. Power is supplied to the offshore unit 20 from a power supply unit (not shown). The power supply unit includes, for example, a rechargeable secondary battery such as a lithium-ion battery, or an offshore power generation device such as a solar panel.

[0027] The target detector 22 is a so-called fish finder, and includes a signal processing unit 22a and a wave transmitting / receiving unit 22b.

[0028] The wave transmitting and receiving unit 22b includes an element capable of converting between an electrical signal and ultrasonic vibration. The wave transmitting and receiving unit 22b is installed facing vertically downward on the underside of the housing of the offshore unit 20. The wave transmitting and receiving unit 22b transmits ultrasonic waves (transmitted waves) downward from near the water surface into the water and receives reflected waves reflected from underwater targets. The wave transmitting and receiving unit 22b transmits an electrical signal based on the received reflected waves to the signal processing unit 22a. The signal processing unit 22a generates an echo signal including the intensity of the reflected wave according to the depth based on the electrical signal of the reflected wave, and transmits the generated echo information to the control unit 21.

[0029] The position detection unit 23 detects the position of the offshore unit 20 based on the GPS. The position detection unit 23 transmits the detected position information to the control unit 21.

[0030] The control unit 21 is composed of a microcomputer, a memory, etc. The control unit 21 controls each part of the offshore unit 20. The control unit 21 generates a transmission packet from the echo signal from the target detector 22 and the position information from the position detection unit 23. The communication unit 24 is composed of a module capable of wireless communication with the base station 31. The control unit 21 performs wireless communication with the base station 31 via the communication unit 24, and transmits the generated transmission packet to the server 40 via the base station 31 and the external communication network 32.

[0031] FIG. 4 is a diagram showing a schematic configuration of a transmission packet transmitted by the control unit 21. As shown in FIG.

[0032] A transmission packet is generated for each predetermined time interval (hereinafter referred to as a "line"). The transmission packet includes a net ID for identifying the fixed net 10, an echo signal for that line, and position information for that line. Figure 4 shows a schematic diagram of echo signals plotted on a graph. The horizontal axis of the echo signal graph indicates water depth. Water depth is obtained by multiplying the time from the transmission of the transmitted wave to the reception of the reflected wave by the speed of sound in water and dividing the result by 2. The vertical axis of the echo signal graph indicates intensity, for example, in decibels. In other words, the echo signal is information including the intensity of the reflected wave received according to the depth.

[0033] Returning to FIG. 3, the server 40 includes a control unit 41, a storage unit 42, and a communication unit 43.

[0034] The control unit 41 is composed of a CPU and the like. The storage unit 42 is composed of a ROM, a RAM, a hard disk and the like. Various programs are stored in the storage unit 42. The control unit 41 executes the functions of a net bottom depth calculation unit 41a, a notification information generation unit 41b, and a transmission processing unit 41c according to the programs stored in the storage unit 42. That is, the control unit 41 in Fig. 3 shows functional blocks executed by the control unit 41 based on the programs.

[0035] The storage unit 42 stores various programs executed by the control unit 41 as well as a DB group 42a. The DB group 42a includes a network database, a time-series database for each network ID, and a user database. The communication unit 43 is connected to the external communication network 32 so as to be able to communicate with the external communication network 32.

[0036] 5(a) to 5(c) are diagrams each showing a schematic configuration of a network database, a time series database, and a user database.

[0037] As shown in Figure 5(a), the net database includes the following items: a net ID for individually identifying multiple set nets 10, the name of the set net 10, a preset reference depth of the bottom 14a of the set net 10, and a preset reference position of the set net 10. The reference depth is the design depth value of the bottom 14a of the set net 10. The reference position is the position of the set net 10 on the earth's surface. The reference depth and reference position are set when the set net 10 is registered in the net database.

[0038] As shown in Fig. 5(b), a time series database is provided for each net ID. The time series database includes, as items, the echo signal received from the corresponding net ID, the depth of the bottom 14a of the fixed net 10 (net bottom depth) calculated from the echo signal, and the position information received from the corresponding net ID.

[0039] As shown in Figure 5(c), the user database includes items such as a user ID for individually identifying multiple users (users of terminal device 50) and a net ID of the fixed net 10 associated with the user ID.

[0040] Returning to Figure 3, the net bottom depth calculation unit 41a calculates the depth of the bottom 14a of the fixed net 10 from the echo signal based on the transmission packet received from the offshore unit 20. The control unit 41 stores the echo signal, net bottom depth, and current position in the corresponding time series database. The notification information generation unit 41b generates notification information based on the calculation result of the depth of the bottom 14a of the fixed net 10. The transmission processing unit 41c transmits the notification information to the terminal device 50 via the communication unit 43 and the external communication network 32. At this time, the transmission processing unit 41c refers to the user database and transmits the generated notification information to the terminal device 50 of the corresponding user ID.

[0041] The terminal device 50 includes a control unit 51, a storage unit 52, a display input unit 53, and a communication unit 54.

[0042] The control unit 51 is configured with a CPU and the like. The storage unit 52 is configured with a ROM, a RAM and the like. The control unit 51 executes various functions according to programs stored in the storage unit 52. The storage unit 52 also stores a program for displaying notification information received from the server 40 on the display input unit 53. The display input unit 53 is configured with a touch panel such as a capacitive touch panel. The communication unit 54 is connected to the wireless router 33 (see FIG. 2) and the external communication network 32 so as to be able to communicate with them.

[0043] Next, the processing of the offshore unit 20, the server 40 and the terminal device 50 will be described.

[0044] FIG. 6 is a flowchart showing the processing of the offshore unit 20 and the server 40.

[0045] The control unit 21 of the offshore unit 20 drives the target detector 22 to send a transmission wave into the water and receive a reflected wave from the water, and acquires an echo signal including the intensity of the received reflected wave according to the depth based on the electrical signal of the reflected wave (S11). The control unit 21 drives the position detection unit 23 to acquire position information of the offshore unit 20 (fixed net 10) based on GPS (S12). Next, the control unit 21 transmits the net ID, the echo signal acquired in step S11, and the position information acquired in step S12 to the server 40 as a transmission packet (see FIG. 4) via the communication unit 24 (S13). The processing of steps S11 to S13 corresponds to one line of processing, and is repeated at predetermined time intervals.

[0046] When the control unit 41 of the server 40 receives a transmission packet from the offshore unit 20 (S21: YES), it performs a net bottom depth calculation process (S22) using the function of the net bottom depth calculation unit 41a to obtain the depth of the bottom 14a of the fixed net 10 where the offshore unit 20 that is the sender of the transmission packet is installed (net bottom depth). The net bottom depth calculation process will be described later with reference to Figure 7. Then, the control unit 41 stores the net bottom depth obtained in step S22 and the echo signal and position information received in step S21 in the corresponding time series database (see Figure 5(b)) (S23).

[0047] The processing of steps S21 to S23 is based on one line of transmission packets received from one offshore unit 20. When the control unit 41 receives transmission packets from multiple offshore units 20, it repeatedly performs the processing of steps S21 to S23 in accordance with each transmission packet.

[0048] FIG. 7 is a flowchart showing the net bottom depth calculation process.

[0049] The control unit 41 of the server 40 performs the processes of steps S101 to S105 based on the echo signal received in step S21 of Fig. 6. The control unit 41 scans the echo signal in the depth direction (S101) and determines whether the intensity of the echo signal at the scanning position is equal to or greater than a threshold value Eth (S102). The threshold value Eth is set to be smaller than the intensity of the wave reflected from the bottom 14a and larger than the intensity of the wave reflected from a general school of fish.

[0050] If the strength of the echo signal is less than the threshold Eth (S102: NO), the control unit 41 returns the process to step S101 and advances the scanning position in the depth direction. On the other hand, if the strength of the echo signal is equal to or greater than the threshold Eth (S102: YES), the control unit 41 further determines whether the scanning position has reached the depth of the seabed (S103). Specifically, the control unit 41 determines that the scanning position has reached the depth of the seabed, for example, if the strength of the echo signal at the scanning position is equal to or greater than the strength of the echo signal corresponding to the depth of the seabed.

[0051] If the scanning position has not reached the seabed depth (S103: NO), the control unit 41 determines whether the net bottom determination is equal to or greater than the threshold Pth% within the depth ±Dth on the nearest line within Lth (S104). If the control unit 41 determines NO in step S104, it returns the process to S101 and moves the scanning position in the depth direction. On the other hand, if the control unit 41 determines YES in step S104, it determines that the scanning position is the position of the bottom 14a and acquires the depth (net bottom depth) from the scanning position. (S105) .

[0052] Furthermore, if the control unit 41 determines that the scanning position has reached the seabed depth (step S103: YES), it ends the process, thus completing the net bottom depth calculation process.

[0053] FIG. 8 is a diagram showing a schematic diagram of echo signals of each line as time passes from line n to line n+6.

[0054] When the current line is line n+6, the control unit 41 advances the scanning position in the depth direction in step S101 of Fig. 7. When the scanning position reaches depth D1, the intensity of the echo signal at this time is less than the threshold value Eth, so the control unit 41 determines NO in step S102, returns the process to step S101, and further advances the scanning position in the depth direction.

[0055] When the scanning position reaches depth D2, the echo signal intensity at this time is equal to or greater than the threshold Eth and less than the echo signal intensity corresponding to the seabed depth, so the control unit 41 proceeds to step S104. Then, the control unit 41 determines whether the net bottom judgment is equal to or greater than the threshold Pth% within the depth ±Dth on the nearest line within Lth.

[0056] In the example shown in FIG. 8, the Lth value is 5, and the five closest lines are surrounded by dashed lines. Within the closest Lth, net bottom determinations are made at lines n+2, n+4, n+5, and n+6 within a depth of ±Dth from the scanning position. That is, a total of four net bottom determinations are made within the closest Lth and a depth of ±Dth from the scanning position. Therefore, in the example shown in FIG. 8, the percentage of net bottom determinations made within a depth of ±Dth from the scanning position is 4 / 5 = 80%. If the threshold Pth% for net bottom determination is set to, for example, 60%, this percentage is equal to or greater than the threshold Pth%. Therefore, the control unit 41 determines that the scanning position in this case is the bottom 14a and obtains the net bottom depth from the scanning position.

[0057] In this way, the processes of steps S101 to S104 in FIG. 7 are repeated until the scanning position reaches the depth of the seabed.

[0058] As described above, by determining whether the scanning position is at the net bottom position based on the net bottom judgment of the nearest line within Lth, it is possible to eliminate cases where a school of fish temporarily crosses and the strength of the echo signal becomes high, and to accurately obtain the position of the bottom 14a of the fixed net 10.

[0059] FIG. 9 is a flowchart showing the processing of the server 40 and the terminal device 50.

[0060] When the control unit 51 of the terminal device 50 receives a request to display notification information from the user via the display input unit 53 (S41: YES), it transmits start request information including the user ID to the server 40 (S42).

[0061] When the control unit 41 of the server 40 receives the start request information from the terminal device 50 (S31: YES), the control unit 41 generates the notification information using the function of the notification information generation unit 41b (S32).

[0062] FIG. 10 is a diagram illustrating a configuration of the notification information.

[0063] The notification information includes the following items: net ID, name of the set net 10, reference depth of the bottom 14a, net bottom depth of the bottom 14a, a change value indicating the degree of change in net bottom depth relative to the reference depth, information indicating the change level of the net bottom depth, echo signals, the reference position of the set net 10, and position information (current position) of the set net 10 (offshore unit 20). The change value and the information indicating the change level are both information indicating the degree of change.

[0064] In the process of generating the notification information, the control unit 41 refers to the user database shown in FIG. 5(c) based on the user ID of the terminal device 50 received from the terminal device 50, and acquires the net ID of the corresponding fixed net 10. The example shown in FIG. 10 shows a state in which the thus acquired net IDs are five, N001 to N005. Then, based on the acquired net ID, the control unit 41 refers to the net database shown in FIG. 5(a) to acquire the corresponding name, reference depth, and reference position. Furthermore, based on the acquired net ID, the control unit 41 refers to the time-series database shown in FIG. 5(b) to acquire the echo signal, net bottom depth, and position information for the most recent line.

[0065] The control unit 41 then acquires a change value based on the acquired reference depth and net bottom depth. For example, the control unit 41 calculates the difference between the reference depth and the net bottom depth as the change value. In the example shown in FIG. 10, the differences (change values) between the reference depth and the net bottom depth for the set nets 10 with net IDs N001 to N005 are 5 m, 0 m, 10 m, 15 m, and 20 m, respectively. Furthermore, the control unit 41 sets the information indicating the change level to "small" when the difference is 0 m or more and less than 10 m, sets the information indicating the change level to "medium" when the difference is 10 m or more and less than 15 m, and sets the information indicating the change level to "large" when the difference is 15 m or more. Therefore, in the example shown in FIG. 10, the information indicating the change level is "small" when the net IDs are N001 and N002, "medium" when the net ID is N003, and "large" when the net IDs are N004 and N005.

[0066] Returning to Figure 9, the control unit 41 of the server 40 generates notification information as shown in Figure 10 (S32), and transmits the generated notification information to the terminal device 50 that accepted the start request information in step S31 using the function of the transmission processing unit 41c (S33).

[0067] When the control unit 51 of the terminal device 50 receives the notification information (S43: YES), it displays the notification information on the display input unit 53 (S44). Thereafter, when the control unit 51 receives a command to end the display from the user via the display input unit 53 (S45: YES), it transmits end request information including the user ID to the server 40 (S46) and ends the process. On the other hand, if the control unit 51 does not receive a command to end the display (S45: NO), in other words, until the control unit 51 receives a command to end the display, it repeats the processes of steps S43 to S45 and displays the notification information transmitted from the server 40 one by one on the display input unit 53.

[0068] When the control unit 41 of the server 40 receives the termination request information from the terminal device 50 (S34: YES), the control unit 41 ends the process. On the other hand, when the control unit 51 does not receive the termination request information (S34: NO), in other words, until the control unit 51 receives the termination request information, the control unit 51 repeats the processes of steps S32 and S33 and transmits the notification information generated for each line to the terminal device 50 one by one.

[0069] FIG. 11 is a diagram schematically showing a screen 100 displayed on display input unit 53 in step S44 of FIG.

[0070] The screen 100 includes an echo signal display area 110 and a map information display area 120 .

[0071] The echo signal display area 110 displays the echo signal of the set net 10 with the net ID and name selected in the pull-down menu 111. The vertical direction of the echo signal display area 110 indicates depth. The rightmost position shows the most recent echo signal, and moving left shows older echo signals. The echo signal display area 110 shown as an example in Figure 11 displays an echo signal with net ID N002, with the bottom 14a of the set net 10 displayed at around 45 m and the seabed displayed at around 90 m.

[0072] The map information display area 120 displays a plurality of round icons 121 corresponding to a plurality of set nets 10, respectively. Each icon 121 is arranged based on the location information of the corresponding set net 10 (location information included in the report information), and indicates the location of the corresponding set net 10. The icon 121 displays the net ID, name, and net bottom depth in a speech bubble 122. The icon 121 also displays information indicating the change level using shades of gray (see FIG. 10). In the example shown in FIG. 11, the lightest color indicates that the information indicating the change level is "small," the darkest color indicates that the information indicating the change level is "large," and the medium color indicates that the information indicating the change level is "medium."

[0073] By referring to the screen 100 shown in FIG. 11, the user (viewer) can make the following decisions, for example.

[0074] The user checks the net bottom depth by referring to the map information display area 120. When the net bottom depth is deep, such as in the case of the fixed net 10 (No. 1) of N001 and the fixed net 10 (No. 2) of N002, it can be determined that the current speed near the fixed net 10 is generally slow, so the user can take fishing action for No. 1 and No. 2.

[0075] In addition, when the net is deep at the bottom, as in No. 1 and No. 2, the user may make a final decision on whether or not to take action to catch fish by referring to the echo signal display area 110. For example, even if the net is deep at the bottom, as in No. 2, if there are almost no schools of fish in the echo signal, the user can decide not to take action to catch fish.

[0076] Furthermore, when the net bottom depth is shallow, such as in the case of the fixed net 10 (No. 4) in N004 and the fixed net 10 (No. 5) in N005, it can generally be determined that the current speed near the fixed net 10 is fast, so the user can postpone fishing actions for Nos. 4 and 5. Furthermore, when the net bottom depth is medium, such as in the case of the fixed net 10 (No. 3) in N003, the user can also refer to the echo signal display area 110 and take fishing action if a school of fish is captured in the echo signal.

[0077] <Effects of the embodiment> According to the embodiment, the following effects can be achieved.

[0078] The net bottom depth calculation unit 41a calculates the depth of the bottom 14a of the set net 10 (net bottom depth) based on the echo signal, the notification information generation unit 41b generates notification information based on the calculation result of the net bottom depth, and the transmission processing unit 41c transmits the notification information to the terminal device 50 via the external communication network 32. With this configuration, notification information regarding the depth of the bottom 14a of the set net 10 can be output via the terminal device 50. This allows a user of the notification information to monitor the state of the bottom 14a of the set net 10 and determine whether or not to proceed a boat to the set net 10 to catch fish.

[0079] The net bottom depth calculation unit 41a estimates the bottom 14a of the fixed net 10 from the echo signals obtained by transmitting sound waves up to a predetermined number of times before the current time, and calculates the depth of the bottom 14a. With this configuration, if a target is detected consecutively at approximately the same depth from these multiple echo signals, the target can be estimated to be the bottom 14a of the fixed net 10.

[0080] The notification information generator 41b generates, as notification information, information indicating the degree of change in the depth of the bottom 14a relative to the reference depth (for example, information indicating the level of change). With this configuration, a viewer of the notification information can understand how much the bottom 14a of the fixed net 10 has changed relative to the reference depth at the current time due to tidal currents, etc. (for example, how much it has risen).

[0081] The notification information generator 41b sets a plurality of change levels relative to the reference depth and generates, as notification information, information (for example, large, medium, small) indicating the change level corresponding to the change in the depth of the bottom 14a relative to the reference depth. With this configuration, a viewer of the notification information can more intuitively understand how much the bottom 14a of the fixed net 10 has changed relative to the reference depth at the current time by referring to the information indicating the change level.

[0082] The position detection unit 23 detects the position of the set net 10 on the ground surface, and the transmission processing unit 41c transmits information about the position of the set net 10 (position information in FIG. 10) to the terminal device 50. With this configuration, a viewer of the notification information can understand not only the notification information but also the position of the set net 10 for which the notification information is indicated (the position on the map indicated by the icon in FIG. 11). This allows the viewer to reliably understand the position of the set net 10.

[0083] The wave transmitting and receiving units 22b are arranged for each of the multiple fixed nets 10, and the net bottom depth calculation unit 41a calculates the depth of the bottom 14a of each fixed net 10 based on the echo signals output from each wave transmitting and receiving unit 22b. With this configuration, a viewer of the notification information can understand the state of the bottom 14a for each fixed net 10.

[0084] An icon 121 corresponding to the net ID (fixed net 10) is displayed in the map information display area 120. The icon 121 is composed of a mark indicating the position of the set net 10 and an image (image with different shading) indicating the state of the bottom 14a of the set net 10. This configuration allows the viewer to intuitively understand the relationship between the position of the set net 10 and the state of the bottom 14a.

[0085] <Change example 1> In the above embodiment, when start request information is transmitted from the terminal device 50 to the server 40, notification information is transmitted from the server 40 to the terminal device 50. In contrast, in this modified example, when the net bottom depth in the server 40 satisfies a predetermined condition, other notification information is transmitted from the server 40 to the terminal device 50.

[0086] 12 is a flowchart showing a process for transmitting other notification information in this modified example. The process shown in FIG. 12 is repeatedly performed for each net ID (fixed net 10) in parallel with the process of the above embodiment.

[0087] When the control unit 41 of the server 40 calculates the net bottom depth in step S22 of Fig. 6 (S51: YES), it refers to the net bottom depth in the time-series database shown in Fig. 5(b) and determines whether a predetermined time Tth has passed since the net bottom depth fell outside a predetermined range Dr (S52). For example, in the example shown in Fig. 13(a), the net bottom depth changes over time, and time Tth has passed since the net bottom depth fell outside the range Dr. In this case, the control unit 41 determines YES in step S52.

[0088] If the determination in step S52 is YES, the control unit 51 transmits other notification information to the terminal device 50 using the function of the transmission processing unit 41c (S53). The other notification information includes information indicating that the condition shown in step S52 has been met, specifically, information indicating that time Tth has elapsed since the net bottom depth fell outside the range Dr. In this modified example, the user database shown in FIG. 5(c) includes items such as email addresses and telephone numbers. In step S53, the control unit 51 refers to the user database and uses the corresponding email address and telephone number to transmit the other notification information to the terminal device 50 by email or SMS. On the other hand, if the determination in step S52 is NO, step S53 is skipped.

[0089] When the control unit 51 of the terminal device 50 receives other notification information from the server 40 (S61: YES), the control unit 51 displays the other notification information on the display input unit 53 (S62).

[0090] The conditions (S52) for transmitting other broadcast information are not limited to those described above. Other broadcast information may be transmitted to the terminal device 50 when the following conditions are met.

[0091] For example, in step S52, the control unit 41 may determine whether a predetermined time Tth has passed since the net bottom depth fell within a predetermined range Dr. For example, in the example shown in Fig. 13(b), the time Tth has passed since the net bottom depth fell within the range Dr. In this case, the control unit 41 determines YES in step S52.

[0092] In step S52, the control unit 41 may also determine whether the net bottom depth has changed by a predetermined amount ΔD or more within a predetermined time Tth. For example, in the example shown in Figure 13(c), the net bottom depth has changed by a predetermined amount ΔD or more within the predetermined time Tth. In this case, the control unit 41 determines YES in step S52.

[0093] In step S52, the control unit 41 may also determine whether there is a possibility that the net bottom depth will reach a predetermined depth. In step S52, the control unit 41 may also determine whether the amount or rate of change in the net bottom depth from the previous line to the current line is equal to or greater than a predetermined amount, or whether the amount of change from the net bottom depth of the current line to the predicted net bottom depth based on a weather forecast for a predetermined time period is equal to or greater than a predetermined amount. In step S52, the control unit 41 may also determine whether the average, maximum, or minimum value of the net bottom depth for a predetermined number of most recent lines is equal to or greater than a predetermined value or equal to or less than a predetermined value.

[0094] <Effects of Change Example 1> When the net bottom depth reaches a predetermined state (S52: YES), the control unit 41 of the server 40 transmits other notification information by email or SMS to the terminal device 50. This allows the user to quickly understand that the condition of step S52 has been met.

[0095] <Change example 2> In the above embodiment, the offshore unit 20 may further include a device for detecting sea conditions.

[0096] FIG. 14 is a block diagram showing the configuration of the offshore unit 20 according to this modified example.

[0097] The offshore unit 20 includes a control unit 21, a target detector 22, a position detection unit 23, and a communication unit 24 similar to those in Fig. 2, as well as a tidal current meter 25. The tidal current meter 25 measures the direction and speed of tidal currents in multiple depth ranges (layers). The measurement results (tidal current information) of the tidal current meter 25 are output to the control unit 21, which then adds the tidal current information to the transmission packet shown in Fig. 4 and transmits the transmission packet to the server 40, as in the above embodiment.

[0098] The control unit 41 of the server 40 stores the power flow information in the received transmission packet in a time-series database for each network ID shown in FIG. 5(b). When the control unit 41 receives start request information from the terminal device 50, in step S32 of FIG. 9, it generates notification information as shown in FIG. 15. Compared to the notification information of FIG. 10, the notification information of FIG. 15 has power flow information added. In step S33 of FIG. 9, the control unit 41 transmits the generated notification information to the terminal device 50, as in the above embodiment.

[0099] In step S44 of FIG. 9, the control unit 51 of the terminal device 50 displays the notification information received from the server 40 on the display input unit 53.

[0100] FIG. 16 is a diagram schematically showing a screen 100 displayed on display input unit 53 in step S44 of FIG. 9 according to this modified example.

[0101] In comparison with the above embodiment, the screen 100 of this modified example has an additional tidal current information display area 112. The tidal current information display area 112 is displayed based on the alarm information, and displays the installation direction of the tidal current meter 25 (the direction in which the offshore unit 20 is facing) and the direction and speed of the tidal current in multiple depth ranges (layers). The tidal current information display area 112 displays the direction and speed of the tidal current in the set net 10 selected in the pull-down menu 111.

[0102] In addition, the icon 121 in the map information display area 120 of this modified example has been changed to an arrow compared to the above embodiment. The direction indicated by the arrow of the icon 121 is set based on the alarm information and indicates the direction of the current in a predetermined layer among the multiple layers. Furthermore, the speech bubble 122 displays the net ID, name, and net bottom depth as well as the current speed in the fixed net 10. The current speed in the speech bubble 122 is the current speed in a predetermined layer among the multiple layers.

[0103] The direction and speed of the current indicated by the icon 121 and the speech bubble 122 are not limited to the direction and speed of the current in a predetermined layer, but may be the direction and speed of the current in a layer set by the user via a reception screen displayed on the display input unit 53. Furthermore, a current information display area 112 corresponding to the set net 10 may be displayed in place of the icon at the position of each icon in the map information display area 120.

[0104] By referring to the screen 100 as shown in FIG. 16, the user (viewer) can make the following decisions in addition to the decisions made in the above embodiment.

[0105] The user checks the net bottom depth by referring to the map information display area 120. When the net bottom depth is deep, such as in the case of the set net 10 (No. 1) of N001 and the set net 10 (No. 2) of N002, it can generally be determined that the current speed near the set net 10 is slow and suitable for fishing. However, even when the current speed is fast, the net bottom depth may occasionally become deep depending on how the current hits the set net 10. The user can anticipate such a situation by referring to the current speed in the current information display area 112 and the speech bubble 122. Therefore, the user can postpone fishing in such cases.

[0106] Furthermore, when the net bottom depth is shallow, as in the case of the set net 10 (No. 4) of N004 and the set net 10 (No. 5) of N005, it can generally be determined that the current speed near the set net 10 is fast, but if some kind of abnormality occurs in the set net 10, the net bottom depth may become shallow even though the current speed near the set net 10 is slow. The user can anticipate such a situation by referring to the current speed in the current information display area 112 and the speech bubble 122. Therefore, in such a case, the user can determine that it is necessary to check the condition of the bottom 14a.

[0107] Furthermore, if the speed of the current is unstable, the user can postpone fishing regardless of the depth of the net bottom. Also, the user can determine the ease of fishing from the direction of the current and the installation angle of the fixed net 10.

[0108] <Effects of Change Example 2> Based on the measurement results of the tidal current meter 25, the direction and speed of the tidal current in multiple depth ranges (layers) are displayed in the tidal current information display area 112. The direction indicated by the arrow of the icon 121 is the direction of the tidal current in the set net 10, and the speech bubble 122 displays the speed of the tidal current in the set net 10. With this configuration, the viewer can understand the state of the bottom 14a of the set net 10 as well as the state of the tidal current in the set net 10.

[0109] <Other change examples> The present invention is not limited to the above-described embodiment, and various modifications to the embodiment of the present invention are possible in addition to the above-described configuration.

[0110] For example, in the above embodiment, the terminal device 50 was an information terminal device such as a smartphone or tablet, but it is not limited to this and may also be a personal computer equipped with a display unit such as a display and an input unit such as a keyboard and a mouse.

[0111] In addition, in the above embodiment, the net bottom depth calculation unit 41a, which calculates the depth of the bottom 14a of the fixed net 10, is provided as a function of the control unit 41 of the server 40, but it may also be provided as hardware in the server 40. The net bottom depth calculation unit 41a may also be provided in the offshore unit 20. A control device may be interposed between the offshore unit 20 and the server 40, and the net bottom depth calculation unit may be arranged in this control device. In addition, in the above embodiment, the net bottom depth calculation unit 41a, the notification information generation unit 41b, and the transmission processing unit 41c are provided in one server 40, but they may also be provided distributed across multiple servers.

[0112] FIG. 17 is a block diagram showing the configuration of the fixed net monitoring system 1 according to a modified example in which the net bottom depth calculation unit is provided in the offshore unit 20.

[0113] In this modified example, compared to the configuration of the above embodiment shown in Fig. 3, the control unit 21 of the offshore unit 20 executes the function of the net bottom depth calculation unit 21a by a program stored in the memory of the control unit 21. Also, compared to the configuration of Fig. 3, the function of the net bottom depth calculation unit 41a has been deleted from the control unit 41 of the server 40.

[0114] FIG. 18 is a flowchart showing the processing of the offshore unit 20 and the server 40 in a modified example in which the net bottom depth calculation unit is provided in the offshore unit 20.

[0115] In the process of Figure 18, step S14 is added between step S12 and step S13, and step S22 is deleted, compared to the process of the above embodiment shown in Figure 3. Below, we will explain the parts that are different from the process of Figure 3.

[0116] The control unit 21 of the offshore unit 20 performs the processes of steps S101 to S105 in Fig. 7 based on the echo signal acquired in step S11 using the function of the net bottom depth calculation unit 21a (S14). Then, the control unit 21 transmits the net ID, the echo signal acquired in step S11, the position information acquired in step S12, and the net bottom depth acquired in step S14 as a transmission packet to the server 40 via the communication unit 24 (S13). When the control unit 41 of the server 40 receives the transmission packet from the offshore unit 20 (S21: YES), it stores the echo signal, position information, and net bottom depth received in step S21 in the corresponding time series database (see Fig. 5(b)) (S23).

[0117] 17 and 18, the control unit 41 of the server 40 generates notification information based on the net bottom depth, etc., using the function of the notification information generation unit 41b, and transmits the notification information to the terminal device 50 using the function of the transmission processing unit 41c. The control unit 51 of the terminal device 50 then displays the received notification information on the screen 100. This allows a user of the notification information to monitor the state of the bottom 14a of the fixed net 10 and to determine whether or not to proceed with fishing by sailing a boat to the fixed net 10. Furthermore, according to this modification, the calculation of the net bottom depth is performed by the offshore unit 20, thereby reducing the load on the server 40.

[0118] In the above embodiment, the reference depth and the reference position are set in advance in the net database (see FIG. 5(a)). However, the reference depth may be set based on the net bottom depth of the set net 10 in a normal state, and the reference position may be set based on the position information of the set net 10 in a normal state. The reference depth and the reference position may also be set and changed by the user operating the terminal device 50. In this case, for example, a reception screen is displayed on the display input unit 53 of the terminal device 50, and the user associates the net ID of the set net 10 with the reference depth and the reference position via the reception screen and registers them in the net database of the server 40. A map for inputting the reference position is displayed on the reception screen, and the user may input the reference position by tapping or otherwise specifying a position on the map.

[0119] 8, the value of Lth was 5 and Pth% was 60%, but these values ​​may be other values ​​as long as the position of the bottom 14a can be obtained accurately by excluding temporary schools of fish. Also, Dth used in the determination in step S104 can be changed as appropriate as long as it can capture the bottom 14a of the fixed net 10 moving up and down in the sea.

[0120] 8, instead of determining whether the net bottom determination is equal to or greater than the threshold Pth%, it may be determined whether the net bottom determination continues for equal to or greater than the threshold Pth%. Also, in step S104, instead of determining the most recent line within Lth, only the most recent (current) line may be determined. Also, in step S104, it may be determined whether the moving average value of the echo signal intensity according to depth is equal to or greater than the threshold Eth.

[0121] In the above embodiment, in step S32 of Fig. 9, the control unit 41 calculates the difference between the reference depth and the net bottom depth as a change value indicating the degree of change of the net bottom depth relative to the reference depth, but this is not limiting, and the ratio of the net bottom depth to the reference depth may be calculated. In this case, information indicating the change level is set depending on whether the ratio is included in one of three ranges.

[0122] Furthermore, in the above embodiment, the icons 121 (see FIG. 11) in the map information display area 120 are arranged based on the position information of the corresponding set net 10, but the control unit 51 of the terminal device 50 may arrange the icons 121 corresponding to each set net 10 based on the reference position included in the notification information. Furthermore, the control unit 51 may calculate the difference between the position information included in the notification information and the reference position, and display on the screen 100 how much the current position of each set net 10 deviates from the reference position. In this way, if the set net 10 is swept away by a large amount due to an unforeseen event, the user can quickly grasp such an event.

[0123] Furthermore, in the above embodiment, the icon 121 displays information indicating the change level using shades of gray, but the colors corresponding to the information indicating the change level are not limited to this. For example, green, yellow, and red may correspond to the information indicating the change level of "small," "medium," and "large," respectively. Furthermore, the size of the icon 121 may change depending on the information indicating the change level. For example, icons 121 of sizes "large," "medium," and "small" may correspond to the information indicating the change level of "large," "medium," and "small," respectively.

[0124] Furthermore, in the above embodiment, instead of the icon 121, a mark indicating the position of the set net 10 and an image indicating the state of the bottom 14a of the set net 10 may be separately arranged in the map information display area 120. Furthermore, a change value of the net bottom depth (change value of the notification information) may be displayed in the speech bubble 122. In this case, the characters of the change value in the speech bubble 122 may be colored in accordance with the information indicating the change level.

[0125] In the above embodiment, some or all of the information in the map information display area 120 (net ID, name, net bottom depth, location information, information indicating change level) may be displayed as a list on the screen 100.

[0126] Furthermore, in the above embodiment, the offshore unit 20 may be equipped with a motion sensor for measuring the motion of the offshore unit 20. In this case, the offshore unit 20 adds the tilt of the offshore unit 20 measured by the motion sensor to the transmitted packet. Based on the tilt of the offshore unit 20, the control unit 41 of the server 40 determines whether the echo signal in the transmitted packet is an appropriate echo signal directed directly below the offshore unit 20, and uses the echo signal to calculate the net bottom depth only if the echo signal in the transmitted packet is appropriate. This improves the accuracy of the calculated net bottom depth.

[0127] In the above embodiment, the control unit 41 of the server 40 may calculate a predicted time until the bottom 14a reaches a predetermined net bottom depth based on the predicted sea state (tidal current) in step S32 of Fig. 9, and add the calculated predicted time to the notification information. In this case, the predicted time until the bottom 14a reaches the predetermined net bottom depth is displayed on the screen 100.

[0128] In the above embodiment, the offshore unit 20 may also be equipped with sensors for detecting other sea condition information such as water temperature, salinity, and dissolved oxygen content. In this case, the other sea condition information is added to a transmission packet and transmitted to the server 40, where it is stored in the database of the server 40. The screen 100 of the terminal device 50 then displays the other sea condition information as appropriate.

[0129] In addition, the embodiments of the present invention can be modified in various ways as appropriate within the scope of the claims. [Explanation of symbols]

[0130] 1. Fixed net monitoring system 10 Fixed nets 14a bottom 20 Offshore Units 21a Net bottom depth calculation section 22b Transmitting and receiving unit 23 Position detection unit 32 External communication network 40 servers 41a Net bottom depth calculation part 41b Notification information generation unit 41c Transmission processing unit 50 Terminal Equipment 51 Control section 53 Display input unit (display unit) 120 Map information display area (map) 121 icons (marks, images)

Claims

1. a wave transmitting / receiving unit that transmits sound waves toward the bottom of a fixed net installed underwater, receives reflected waves of the sound waves, and outputs an echo signal; a net bottom depth calculation unit that calculates the bottom depth of the fixed net based on the echo signal; a notification information generating unit that generates notification information based on the calculation result of the bottom depth; a transmission processing unit that transmits the notification information to a terminal device via an external communication network, The net bottom depth calculation unit acquires the calculation result of the bottom depth of the set net based on the echo signals obtained by transmitting the sound waves from this time to a predetermined number of times before, when the bottom depth of the set net calculated by transmitting the sound waves this time can be adopted. A fixed net monitoring system characterized by:

2. The fixed net monitoring system according to claim 1, The net bottom depth calculation unit acquires the calculation result of the current bottom depth as the bottom depth of the fixed net when the index value based on the echo signal by the transmission of the sound wave from this time to a predetermined number of times before satisfies the predetermined condition for adoption. A fixed net monitoring system characterized by:

3. 3. The fixed net monitoring system according to claim 1, The notification information generation unit generates, as the notification information, information indicating a degree of change in the bottom depth relative to a reference depth. A fixed net monitoring system characterized by:

4. The fixed net monitoring system according to claim 3, the notification information generation unit sets a plurality of change levels with respect to the reference depth, and generates, as the notification information, information indicating the change levels corresponding to changes in the depth of the bottom with respect to the reference depth. A fixed net monitoring system characterized by:

5. The fixed net monitoring system according to any one of claims 1 to 4, a position detection unit that detects the position of the fixed net on the ground surface, The transmission processing unit transmits information regarding the position of the set net to the terminal device. A fixed net monitoring system characterized by:

6. The fixed net monitoring system according to any one of claims 1 to 5, The wave transmitting and receiving units are respectively arranged for a plurality of fixed nets, The net bottom depth calculation unit calculates the bottom depth of each of the fixed nets based on the echo signals output from each of the wave transmitting and receiving units. A fixed net monitoring system characterized by:

7. The fixed net monitoring system according to any one of claims 1 to 6, a server located on the ground and connected to the external communication network; an offshore unit that is installed in the fixed net and is capable of communicating with the server, the transmitting and receiving unit is disposed in the offshore unit, the notification information generating unit and the transmission processing unit are arranged in the server; A fixed net monitoring system characterized by:

8. The fixed net monitoring system according to claim 7, The net bottom depth calculation unit is disposed in the server. A fixed net monitoring system characterized by:

9. The fixed net monitoring system according to claim 7, The net bottom depth calculation unit is disposed in the offshore unit. A fixed net monitoring system characterized by:

10. calculating the depth of the bottom of a fixed net installed underwater based on echo signals corresponding to reflected waves of sound waves transmitted toward the bottom of the fixed net; generating notification information based on the calculation result of the bottom depth; transmitting the notification information to a terminal device via an external communication network; In calculating the bottom depth of the set net, if it is possible to adopt the bottom depth of the set net calculated by the current transmission of the sound waves based on the echo signals obtained by each of the current transmissions of the sound waves up to a predetermined number of times before, the calculation result of the bottom depth of the set net is acquired as the bottom depth of the set net. A fixed net monitoring method characterized by:

11. A program for causing a control unit of a terminal device capable of communicating with the fixed net monitoring system according to any one of claims 1 to 9 via an external communication network to execute a predetermined function, a function of receiving the notification information from the fixed net monitoring system via the external communication network; and a function of displaying the notification information on a display unit of the terminal device.

12. The program according to claim 11, the notification information includes information indicating a degree of change in the depth of the bottom relative to a reference depth, The program, wherein the function of displaying the notification information includes a function of displaying on the display unit the degree of change in the bottom depth relative to the reference depth.

13. 13. The program according to claim 12, the notification information includes information indicating a change level corresponding to a change in the depth of the bottom relative to the reference depth, among a plurality of change levels preset with respect to the reference depth, The program, wherein the function of displaying the notification information includes a function of displaying the change level on the display unit.

14. 14. The program according to claim 11, In the function of receiving the notification information, information regarding the position of the set net is further received, The program, wherein the function of displaying the notification information includes a function of displaying information regarding the position of the fixed net on the display unit.

15. 15. The program according to claim 14, The function of displaying information regarding the position of the fixed net on the display unit is a program that displays a map of the area including the position of the fixed net, and includes on the map a mark indicating the position of the fixed net and an image showing the condition of the bottom of the fixed net.

Images