Submarine magnetic exploration device

Abstract

The present invention provides a seabed magnetic exploration device that can suppress the difference in distance from each magnetic sensor to the seabed. [Solution] A seabed magnetic exploration device for exploring hazardous materials on the seabed F by measuring the distance of multiple magnetic sensors 12 to 21 fixed to a frame 11 that moves underwater, spaced apart in the width direction W perpendicular to the direction of travel T of the frame 11, comprising: multiple transducers fixed to different locations in the width direction of the frame 11, each transmitting sound waves toward the seabed F and receiving reflected waves; distance derivation means for deriving the distance from each transducer to the seabed F based on the time difference from the transmission of sound waves to the reception of reflected waves of each transducer; and tilt adjustment means 25, 26, 27, 28 for adjusting the tilt of the frame 11 in the width direction.

Description

Technical Field

[0001] The present invention relates to a submarine magnetic exploration device for exploring dangerous objects on the seabed.

Background Art

[0002] As described in Patent Documents 1 and 2, in a sea area where there may be dangerous objects such as unexploded bombs and naval mines on the seabed, marine exploration is carried out to ensure the safety of marine engineering and ship navigation. In a conventional ship-towed marine exploration using magnetic sensors, as shown in FIGS. 6(A) and (B), a towing ship 103 tows a mother ship 102 with a frame body 101 to which a plurality of magnetic sensors 100 are fixed suspended, so that the frame body 101 is moved in the sea in a state where it is arranged substantially horizontally.

[0003] The plurality of magnetic sensors 100 are provided at intervals in a direction perpendicular to the traveling direction of the frame body 101 (hereinafter referred to as the "width direction"). Since the detection of dangerous objects is performed from the seabed (seabed surface) to a predetermined depth, the frame body 101 needs to move in the sea while keeping the distance to the seabed within a predetermined range (for example, 1 m or less).

[0004] In this regard, the acoustic depth finder 104 attached to the mother ship 102 is adjusted in the sound wave transmission direction and the like so as to measure the distance from the acoustic depth finder 104 to the frame body 101 and the distance from the acoustic depth finder 104 to the seabed. Since the distance from the frame body 101 to the seabed can be detected based on the measurement of the acoustic depth finder 104, the operator operates the winch on the mother ship 102 according to the detection result to raise or lower the frame body 101 and adjust the distance from the frame body 101 to the seabed.

Prior Art Documents

Patent Documents

[0005]

Patent Document 1

Patent Document 2

Summary of the Invention

[0006] However, although the frame 101 has a certain length or more in the width direction (for example, 8m in length), the frame 101 is generally positioned horizontally in the sea. Therefore, if, for example, the seabed is sloped in the width direction of the frame 101, there is a problem in that the distance from the magnetic sensor 100 to the seabed will differ depending on the magnetic sensor 100.

[0007] This invention has been made in view of the above circumstances, and aims to provide a seabed magnetic exploration device that can suppress the difference in distance from each magnetic sensor to the seabed. [Means for solving the problem]

[0008] A seabed magnetic exploration device according to the present invention, which is in line with the above objective, is a seabed magnetic exploration device that explores dangerous objects on the seabed by measuring a plurality of magnetic sensors fixed to a frame that moves in the sea at intervals in the width direction perpendicular to the direction of movement of the frame, and comprises a plurality of transducers fixed at different locations in the width direction of the frame, each transmitting sound waves toward the seabed and receiving reflected waves, a distance derivation means for deriving the distance from each transducer to the seabed based on the time difference from the transmission of sound waves from each transducer to the reception of reflected waves, and a tilt adjustment means for adjusting the tilt of the frame in the width direction. [Effects of the Invention]

[0009] The seabed magnetic exploration device according to the present invention includes a plurality of transducers fixed at different locations in the width direction of the frame, each transmitting sound waves toward the seabed and receiving reflected waves; a distance derivation means for deriving the distance from each transducer to the seabed based on the time difference from the transmission of sound waves to the reception of reflected waves from each transducer; and a tilt adjustment means for adjusting the tilt of the frame in the width direction. Therefore, it is possible to suppress the difference in distance from each magnetic sensor to the seabed. [Brief explanation of the drawing]

[0010] [Figure 1]This is an explanatory diagram of a seabed magnetic exploration device according to one embodiment of the present invention. [Figure 2] (A) and (B) are explanatory diagrams of the frame structure, respectively. [Figure 3] This is an explanatory diagram showing the connections of the signal control unit. [Figure 4] This is a diagram illustrating the data processing performed by the signal control unit. [Figure 5] This is an explanatory diagram showing how the frame is inclined in the width direction of the frame. [Figure 6] (A) and (B) are explanatory diagrams of conventional barge-towing methods for sea exploration, respectively. [Modes for carrying out the invention]

[0011] Next, with reference to the attached drawings, embodiments of the present invention will be described to facilitate understanding of the invention. As shown in Figures 1, 2(A), and 2(B), the seabed magnetic exploration device 10 according to one embodiment of the present invention is a device that explores hazardous materials on the seabed F by measuring measurements taken by a plurality of magnetic sensors 12 to 21 fixed to the frame 11 at intervals in the width direction W perpendicular to the direction of movement T of the frame 11. A detailed explanation follows below.

[0012] In this embodiment, the seabed magnetic survey device 10 is used together with a tugboat 22 and a barge 23, as shown in Figure 1. The tugboat 22 tows the barge 23 by a towing rope 24 connecting the tugboat 22 and the barge 23. Although the seabed magnetic survey device 10 is a device used for surface exploration using a barge towing method, the seabed magnetic survey device 10 can also be applied to self-propelled surface exploration by design modifications (i.e., the present invention).

[0013] As shown in Figures 1 and 2(A), the frame 11 is connected to the other ends of wires 27 and 28, one end of which is fixed to winches 25 and 26 attached to the barge 23, respectively. The outer edge of the frame 11 is rectangular in shape, elongated in the width direction W. The other end of the wire 27 is connected to one side of the frame 11 in the width direction W (the left side in this embodiment), and the other end of the wire 28 is connected to the other side of the frame 11 in the width direction W (the right side in this embodiment).

[0014] A tow rope 29 is attached to the front side of the frame 11 in the direction of travel T, connecting the frame 11 to the towboat 22. The frame 11 is suspended from the barge 23 via wires 27 and 28 to winches 25 and 26, and is towed by the towboat 22 via the tow rope 29, moving through the sea in the direction of travel T. Winches 25 and 26 each have a manually operated control unit (such as a handle, buttons, or touch panel) not shown.

[0015] The winch 25 raises or lowers one side of the frame 11 in the width direction W by winding up or unwinding the wire 27 in response to operation of the winch 25's operating section. The winch 26 raises or lowers the other side of the frame 11 in the width direction W by winding up or unwinding the wire 28 in response to operation of the winch 26's operating section. The tilt of the frame 11 in the width direction W and the distance of the frame 11 from the sea surface (vertical position) can be adjusted by winches 25 and 26. In this embodiment, the tilt adjustment means for adjusting the tilt of the frame 11 in the width direction is mainly composed of winches 25 and 26 and wires 27 and 28.

[0016] As shown in Figures 2(A) and (B), multiple (five in this embodiment) elongated magnetic sensor probes 30 to 34 are fixed to the frame 11 at different positions in the width direction W of the frame 11. The magnetic sensor probes 30 to 34 are arranged parallel to each other and each is aligned along the direction of travel T. The magnetic sensor probe 30 has magnetic sensors 12 and 13 on the front side and the rear side in the traveling direction T, the magnetic sensor probe 31 has magnetic sensors 14 and 15 on the front side and the rear side in the traveling direction T, the magnetic sensor probe 32 has magnetic sensors 16 and 17 on the front side and the rear side in the traveling direction T, the magnetic sensor probe 33 has magnetic sensors 18 and 19 on the front side and the rear side in the traveling direction T, and the magnetic sensor probe 34 has magnetic sensors 20 and 21 on the front side and the rear side in the traveling direction T.

[0017] Therefore, the magnetic sensors 12, 14, 16, 18, and 20 are arranged at different positions in the width direction W of the frame body 11, and the magnetic sensors 13, 15, 17, 19, and 21 are arranged at different positions in the width direction W of the frame body 11. As shown in FIGS. 2(A) and 3, the magnetic sensors 12 to 21 are respectively connected to a signal control unit 35 fixed to the frame body 11. Needless to say, the magnetic sensor probes 30 to 34, the signal control unit 35, etc. fixed to the frame body 11 are waterproof designed.

[0018] The magnetic sensors 12 to 21 respectively measure a magnetic field (magnetic field), output the measured value (hereinafter, also referred to as "magnetic field measurement value") as analog data, and transmit it to the signal control unit 35. As shown in FIG. 3, the signal control unit 35 includes an A / D converter 36 that converts the analog data of the magnetic field measurement values of the magnetic sensors 12 to 21 into digital data, and a multiplexer 38 that processes the digital data output from the A / D converter 36 so that it can be transmitted via a single transmission line (signal line) 37. The multiplexer 38 is connected to a data processing unit 39 equipped on the pontoon boat 23 via the transmission line 37.

[0019] In FIG. 3, it is described that the A / D converter 36 (signal control unit 35) is connected to the magnetic sensor probe 30 in a one-to-one manner. Actually, the A / D converter 36 is connected to each of the magnetic sensors 12 and 13 in a one-to-one manner so that the magnetic field measurement values are independently transmitted from the magnetic sensors 12 and 13 to the A / D converter 36. The same applies to the connection between the A / D converter 36 and each of the magnetic sensor probes 31, 32, 33, and 34.

[0020] The A / D converter 36 receives analog data of magnetic field measurements output from magnetic sensors 12 to 21 in parallel and converts each of them into digital data. The multiplexer 38 acquires the digital data of the magnetic field measurements from each of the magnetic sensors 12 to 21 (10 channels of digital data) from the A / D converter 36 at approximately the same time, and processes each of these digital data to be arranged in series with a time difference in the time axis, as shown in Figure 4 (i.e., by parallel serial conversion), so that the 10 channels of digital data can be transmitted to the data processing unit 39 via a single transmission line (signal line) 37.

[0021] Therefore, in this embodiment, the signal control unit 35 converts the measured values ​​of each of the multiple magnetic sensors 12 to 21, which are received in parallel, into parallel-to-serial format and transmits them via a single transmission line 37 to a data processing unit 39 installed on a barge 23, which is an example of a ship.

[0022] Furthermore, as shown in Figures 2(A) and (B), acoustic detectors 40 and 41 for measuring the distance to the seabed F are fixed to the frame 11 at different locations in the width direction W of the frame 11. In this embodiment, the acoustic detectors 40 and 41 are located on the left (one side) and right (the other side), respectively, with respect to the center of the width direction W of the frame 11, and the positions of the acoustic detectors 40 and 41 in the direction of travel T of the frame 11 are the same (substantially the same).

[0023] As shown in Figure 3, the acoustic probe 40 includes a transducer 42 that transmits sound waves toward the seabed F and receives reflected waves reflected from the seabed F, and a calculation unit 43 that derives the distance from the transducer 42 (acoustic probe 40) to the seabed F based on the time difference between the transmission of sound waves by the transducer 42 and the reception of reflected waves. The acoustic probe 41 also includes a transducer 44 corresponding to the transducer 42 and a calculation unit 45 corresponding to the calculation unit 43, and measures the distance from the transducer 44 (acoustic probe 41) to the seabed F.

[0024] In this embodiment, the distance derivation means for deriving the distance from each transducer 42, 44 to the seabed F is configured to include calculation units 43, 45, but the distance derivation means may also be a single calculation circuit connected to the transducers 42, 44. Here, the acoustic probes 40 and 41 are each connected to the signal control unit 35, which can receive data from the acoustic probes 40 and 41. In this embodiment, the acoustic probes 40 and 41 transmit digital data of the distance from the transducer 42 to the seabed F, and digital data of the distance from the transducer 44 to the seabed F, respectively, to the multiplexer 38.

[0025] The multiplexer 38 (i.e., the signal control unit 35) receives the digital data from the acoustic probes 40 and 41 (i.e., the distance from the transducers 42 and 44 to the seabed F, respectively, which is derived and output by the distance derivation means), and transmits it to the data processing unit 39 via the transmission line 37, along with the digital data of the measured values ​​of the multiple magnetic sensors 12 to 21, arranged in series with respect to the time axis (i.e., converted from serial to parallel), as shown in Figure 4.

[0026] The data processing unit 39 can acquire and output the distance from the transducers 42 and 44 transmitted by the multiplexer 38 to the seabed F (the result of the distance derivation means). Output of the result of the distance derivation means by the data processing unit 39 means output to a device connected to the data processing unit 39, such as a screen, printer, or recorder. Workers on the barge 23 can check the distance from the transducers 42 and 44 to the seabed F from the output of the data processing unit 39.

[0027] As explained above, in this embodiment, data communication from the frame 11 to the barge 23 regarding the measured values ​​of each magnetic sensor 12 to 21 and the distance from the transducers 42 and 44 to the seabed F is performed via a single transmission line 37. The cable having the transmission line connecting the frame 11 and the barge 23 is subjected to seawater resistance when the frame 11 is submerged in the sea, so minimizing the number of transmission lines makes it easier to handle the transmission lines (for example, to retrieve the transmission line from underwater).

[0028] Furthermore, the reason why the acoustic detectors 40 and 41 are fixed to different locations in the width direction W of the frame 11 is so that workers on the barge 23 can operate the winches 25 and 26 while checking how the seabed F below the frame 11 is inclined with respect to the width direction W of the frame 11, based on the measurements of the acoustic detectors 40 and 41, and thereby maintain the distance from each part of the frame 11 to the seabed F within a predetermined range (hereinafter referred to as "this effect").

[0029] For example, as shown in Figure 5, if the frame 11 is positioned in a region where the seabed F slopes downward from one side in the width direction W of the frame 11 (the right side in Figure 5, but actually the left side) to the other side in the width direction W of the frame 11 (the left side in Figure 5, but actually the right side), the slope of the seabed F can be confirmed from the measurements of the acoustic detectors 40 and 41, and the workers on the barge 23 can tilt the frame 11 by operating the winches 25 and 26 so that one side in the width direction W of the frame 11 is positioned higher than the other side in the width direction W.

[0030] To achieve this effect, it is sufficient to fix only the transducers 42 and 44 to different locations in the width direction W of the frame 11, and it is not necessary to place the entire acoustic detector 40 and the entire acoustic detector 41 at different locations in the width direction W of the frame 11. Furthermore, to achieve this effect, it is sufficient to install only the operating part of the tilt adjustment means on the barge 23, which is an example of a ship from which the frame 11 is suspended, and it is not necessary to install the entire tilt adjustment means on the barge 23 (for example, a part of the winch or a part other than the operating part may be placed below the barge 23).

[0031] The number of transducers fixed to different locations in the width direction W of the frame 11 does not need to be more than two; for example, three such transducers may be provided. To achieve this effect, it is sufficient to place the transducers at different positions in the width direction W of the frame 11, and it is not necessary to place transducers on one side and the other side of the width direction W with respect to the center of the width direction W of the frame 11. However, from the viewpoint of stably achieving this effect, it is preferable to place one or more transducers on one side and the other side of the width direction W with respect to the center of the width direction W of the frame 11.

[0032] Furthermore, as shown in Figure 3, a position detection means 46 is connected to the data processing unit 39 to detect the current position using a satellite positioning system. In this embodiment, the position detection means 46 is fixed on the barge 23. Since the frame 11 moves together with the tugboat 22 and the barge 23 while being located approximately directly below the barge 23, in this embodiment, the position detected by the position detection means 46 is used as the position of the frame 11.

[0033] The data processing unit 39 acquires the position information of the frame 11 detected by the position detection means 46 (derived by the satellite positioning system) from the position detection means 46, associates (links) the measured values ​​of each magnetic sensor 12-21 with the position information of the frame 11 at the time the measured values ​​of each magnetic sensor 12-21 were taken, and outputs it to a device such as a screen connected to the data processing unit 39. By designing it in this way, it becomes unnecessary to re-associate the measured values ​​of each magnetic sensor 12-21 with the position information of the frame 11, and it becomes possible to efficiently identify the location where the possibility of hazardous materials being present on the seabed F is detected.

[0034] Although embodiments of the present invention have been described above, the present invention is not limited to the above-described forms, and any changes to the conditions, etc., that do not depart from the gist of the invention are all within the scope of application of the present invention. For example, the data processing unit does not need to acquire the position information of the frame. Alternatively, the measured values ​​output from multiple magnetic sensors may be sent to the data processing unit without undergoing parallel-to-serial conversion. This also applies to the distance from the transducer to the seabed.

[0035] The winch may be automatically controlled based on the distance measurement from the transducer to the seabed to adjust the vertical position and tilt of the frame. The tilt adjustment mechanism is not limited to one having a winch. [Explanation of Symbols]

[0036] 10: Seafloor magnetic exploration device, 11: Frame, 12-21: Magnetic sensors, 22: Tugboat, 23: Barge, 24: Towing rope, 25, 26: Winch, 27, 28: Wire, 29: Towing rope, 30-34: Magnetic sensor probe, 35: Signal control unit, 36: A / D converter, 37: Transmission line, 38: Multiplexer, 39: Data processing unit, 40, 41: Acoustic probe, 42: Transducer, 43: Calculation unit, 44: Transducer, 45: Calculation unit, 46: Position detection means, F: Seafloor, T: Direction of travel, W: Width direction

Claims

1. A seabed magnetic exploration device that searches for hazardous objects on the seabed by measuring the size of multiple magnetic sensors fixed to a frame that moves underwater, with the sensors spaced apart in the width direction perpendicular to the direction of movement of the frame, Multiple transducers are fixed to different locations in the width direction of the frame, each transmitting sound waves toward the seabed and receiving reflected waves, A distance derivation means for deriving the distance from each of the aforementioned transducers to the seabed based on the time difference between the transmission of sound waves from each of the aforementioned transducers and the reception of reflected waves, A seabed magnetic exploration device characterized by comprising tilt adjustment means for adjusting the tilt of the frame in the width direction.

2. The seabed magnetic exploration apparatus according to claim 1, further comprising a data processing unit that acquires the measured values ​​of each of the magnetic sensors and the position information of the frame derived by a satellite positioning system, and associates the measured values ​​of each of the magnetic sensors with the position information of the frame at the time the measured values ​​of each of the magnetic sensors were measured.

3. The seabed magnetic exploration apparatus according to claim 1, characterized in that a signal control unit is attached to the frame, which converts the measured values ​​of each of the multiple magnetic sensors, which are output from and received in parallel from the multiple magnetic sensors, into parallel-to-serial format and transmits them via a single transmission line to a data processing unit installed on the ship.

4. The seabed magnetic exploration apparatus according to claim 3, characterized in that the signal control unit also receives the distance from each of the transducers to the seabed derived and output by the distance derivation means, and transmits this distance, along with the measured values ​​of each of the plurality of magnetic sensors, to the data processing unit via the transmission line after performing a parallel serial conversion.

5. The tilt adjustment means has an operating part that is operated manually, The seabed magnetic exploration apparatus according to claim 1, characterized in that a data processing unit that acquires and outputs the derivation result of the distance derivation means and the operating unit are provided on a ship that suspends the frame.

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