JP2003215230A - Position detection system for underwater moving body and its method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a position detection system capable of determining in real time three-dimensional position of moving body underwater easily and accurately. <P>SOLUTION: The system is constituted of a buoy 40 placed on the sea in a diving sea area, a submersible 20 and a ground station 60. The geographic position of the buoy 40 itself is specified by GPS 42 installed in the buoy 40. The submersible 20 specifies relative position on the basis of the buoy 40 using: (i) a depth value obtained with an installed depth meter 21, (ii) a distance from the buoy specified from the time of ultrasonic transmission/reception (back and forth) with the buoy 40, and (iii) azimuth from the buoy 40 specified based on ultrasonic wave emitted from the buoy to all directions and indicating the due north and the ultrasonic wave emitted later at every certain time interval to the azimuth increasing a certain angle. From the relative position and the geographic position of the buoy 40 which is informed from the buoy 40, the geographic three-dimensional position of the submersible is determined. <P>COPYRIGHT: (C)2003,JPO

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a system for detecting the position of a moving body in water, and more particularly to a system for detecting the three-dimensional position of a moving body.

[0002]

2. Description of the Related Art Conventionally, there is a method of using a dead reckoning device such as an inertial navigation system or a Doppler sonar navigation system as a method for determining the position of a moving body that moves underwater (including undersea) such as a submersible. . This is, for example,
GPS when the submarine is at or near the sea level
The position of the submersible is determined by resetting the position by wireless information such as (Global Positioning System) and then specifying the amount of movement thereafter by measurement using inertia such as a gyrocompass.

However, in the method using such a dead reckoning device, errors are accumulated with time, and the position accuracy is deteriorated. Therefore, it is necessary to reset the position at an appropriate frequency. However, since radio waves are significantly attenuated in the sea, the mobile body (submersible) must spend a great deal of time and energy every time it resets its position to float from the deep sea to the sea surface. For this reason, a technique for identifying the position of the submarine without leaving the surface of the sea and staying underwater is required.

As one of the conventional techniques, based on signals from a plurality of acoustic transponders installed on the seabed,
There is a method of determining the position of a submersible by the principle of triangulation. However, this method requires that three transponders be installed at predetermined positions on the seabed where the exact position is known, in order to determine the three-dimensional position of the submersible. In other words, it is necessary to install at least three transponders on the bottom of the deep sea, to specify the exact position of the seabed, and to install each transponder at that position.

As another conventional technique for determining the position of a submersible boat, there is a "submersible boat position determining device using a magnetic marker" described in Japanese Patent Laid-Open No. 6-323865. In this method, a magnetic marker such as a permanent magnet is installed on the seabed, and a magnetometer for detecting magnetism in three dimensions provided on the submersible determines the relative position of the submersible to the magnetic marker.

However, this method requires a magnetometer which can detect a magnetic field in a three-dimensional direction with high accuracy. In other words, it is necessary to eliminate the influence of the magnetic noise generated by the submersible, and it becomes difficult to accurately determine the position with the magnetometer provided inside the submersible. Therefore, in this position determining device, a boom extending outward from the hull of the submersible is provided,
We are trying to improve the accuracy by attaching a search coil etc. to the end of the boom, but such a boom is
The large protrusion from the hull of the submersible hinders navigation and may cause collision with other objects.

[0007]

SUMMARY OF THE INVENTION Therefore, the present invention has been made in view of such a situation, and requires the troublesome work of installing transponders or the like at a plurality of predetermined positions on the seabed. Without, and without providing a magnetic sensor or the like at a portion protruding from the hull of the submersible, the three-dimensional position of the moving body in water is determined, that is, the three-dimensional position of the moving body in water is easily and accurately determined. An object of the present invention is to provide a position detection system and a method therefor capable of making a real-time determination.

[0008]

In order to achieve the above object, a position detecting system according to the present invention comprises a floating body such as a buoy, a moving body such as a submersible boat, and a land which are installed above the sea in a submersible area. And the base station of The geographical location of the buoy itself is specified by the GPS built into the buoy. The submersible is equipped with (i) the depth value obtained from the equipped depth gauge, (ii) the distance from the buoy specified by the time of ultrasonic transmission / reception (round trip) to / from the buoy, and (iii) the entire buoy. Relative to the buoy as the base point, from the ultrasonic wave indicating the true north transmitted in the direction and the azimuth from the buoy specified based on the ultrasonic wave transmitted toward the azimuth that increases by a certain angle at a certain time interval thereafter. Identify the location. From this relative position and the geographical position of the buoy notified from the buoy, the geographical three-dimensional position of the submarine is determined.

The relative position of the submersible and the geographical position of the buoy are
Radio waves from buoys are transmitted to land-based base stations and are used to monitor submersibles at the base stations.

More specifically, the distance between one buoy installed on the sea and the submersible system in the sea is measured by transmitting a coded ultrasonic wave capable of identifying the ship from the submersible in all directions. , The buoy that receives the signal immediately transmits an ultrasonic signal in which the identification signal of the submersible is mixed with the identification signal of the buoy in all directions. The submersible boat that has received the signal from the buoy can determine the distance between the buoy and the submersible boat from the time from the transmission time to the reception time and the speed of the ultrasonic waves in the sea.

In order to detect the direction of the submarine using the buoy as a base point, the ultrasonic scanner of the buoy first transmits an ultrasonic signal containing a code indicating true north to all directions. After that, in the clockwise direction from the base point of the ultrasonic scanner, toward an azimuth increasing by a certain angle, an ultrasonic signal including a code indicating the azimuth is transmitted with directivity. When transmitting the code indicating true north, the buoy position information (longitude, latitude) by GPS is also included.

The submarine receiving these signals can determine the bearing of its own ship from the time it takes to decode the codes and receive the code of the base point (true north) until the next coat is received. . Further, since the bearing of the ship itself can be known from the received code itself, an accurate bearing can be obtained by mutual comparison with the bearing obtained from the time.

In this way, the submersible specifies the relative position (three-dimensional position) of its own ship with the buoy as the base point, based on the water depth, the distance from the buoy, and the bearing from the buoy. Then, the geographical position of the own ship can be specified from the relative position and the geographical position of the buoy notified from the buoy.

[0014]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of a "position detection system for a moving body in water" according to the present invention will be described below in detail with reference to the drawings. In the following description, the floating body provided above the water is a buoy and the moving body moving underwater is a submersible boat.

FIG. 1 is a diagram showing the components of a position detecting system 10 for a submersible boat in the present embodiment. The position detection system 10 includes a submersible boat 20 which is an object of position detection, a buoy 40 which is a floating body installed on the sea used for the position detection, and a buoy 4 with respect to the position of the submersible boat 20.
The base station 60 collects information transmitted from 0 and monitors the position of the submersible boat 20.

FIG. 2 is a block diagram showing the configuration of the position detecting device provided in the submersible boat 20. The submersible 20 includes a depth gauge 21, a tide gauge 22, a gyro compass 23, an underwater display unit 24, a GPS antenna 25, a GPS horizontal display unit 26, a controller 27, a transmission / reception unit 28, an ultrasonic wave transmitter 29, and an ultrasonic wave receiver. It is provided with vessels 30a and 30b and a transceiver 31.

The water depth gauge 21 is a measuring instrument for detecting the water depth of the submersible boat 20, and the tidal current gauge 22 is a measuring instrument for detecting the direction and speed of the tidal current. The gyro compass 23 is
It is a device that detects the direction, movement distance, and the like of the submersible boat 20 based on inertia, and is used supplementarily for determining the position of the submersible boat 20 in this system.

The controller 27 is provided with a buoy 40 via a transmitting / receiving section 28, an ultrasonic wave transmitter 29 and an ultrasonic wave receiver 30a.
Based on the timing and the code of the ultrasonic signal from the buoy 40 received via the ultrasonic receiver 30b and the transmitting / receiving unit 31. It is an arithmetic and control unit that specifies the bearing of the ship based on the buoy 40, and outputs the specified distance and bearing from the buoy 40 to the underwater display unit 24 together with the data obtained by the tidal current meter 22 and the gyro compass 23. To do.

The transmission / reception unit 28 modulates the data output from the controller 27 with a constant carrier wave, amplifies the power, and then applies the power to the ultrasonic wave transmitter 29 or the ultrasonic wave receiver 30a.
Demodulates the received signal from. The transmission / reception unit 31 demodulates the reception signal from the ultrasonic wave receiver 30b. The ultrasonic wave transmitter 29 is an omnidirectional wave transmitter that converts an electric signal into an ultrasonic wave and outputs the ultrasonic wave. The ultrasonic wave receivers 30a and 30b are
It is an omnidirectional receiver that converts ultrasonic waves into electrical signals.

The underwater display unit 24 displays the depth of the submersible boat 20 in the sea based on the data indicating the water depth sent from the depth gauge 21 and the data sent from the controller 27 indicating the distance and direction from the buoy 40. Diagram showing position (eg,
It is an image display device that generates a diagram (showing the positions of the buoy 40 and the submersible boat 20 in a sectional view in the sea that is perpendicular to the sea surface and passes through the buoy 40 and the submersible boat 20) and displays it on a screen such as an LCD. At this time, the data obtained by the tidal current meter 22 and the gyro compass 23 and the ultrasonic wave receiver 3 from the buoy 40 are received.
The identification code of the buoy 40 obtained through 0a and the geographical position of the buoy 40 stored corresponding to the identification code are also displayed.

The GPS horizontal display section 26 is used for the submersible boat 20.
When the submarine is located at or near the sea, based on the GPS signal received by the GPS antenna 25, the submersible 2
It is an image display device that specifies a geographical position of 0 and displays the result on a screen together with surrounding maps and nautical charts. When the submersible 20 is underwater, the geographical position of the submersible 20 obtained by the gyro compass 23 is displayed for confirmation instead of the GPS signal.

FIG. 3 is an external view of the buoy 40. The buoy 40 transmits / receives ultrasonic waves to / from the sea (and the submersible 20 in the sea) while staying at a predetermined position on the sea, and also transmits to the base station 60 on land by radio waves. An antenna 41 that also receives a GPS signal and transmits to a base station 60, a solar cell 55 that serves as a power source of a power source to supply each built-in circuit, and maintains a fixed position against a tidal current. A thruster (propulsion device) 45, an ultrasonic wave transmitter 48 for transmitting and receiving ultrasonic waves in the sea, an ultrasonic wave receiver 51, a weight 57 and the like.

The antenna 41 and the ultrasonic wave receiver 51
Has no directivity in the horizontal plane (non-directional). On the other hand, the ultrasonic transmitter 48 is a group (array) of 36 transducers arranged radially as shown in the figure,
By selectively operating these oscillators, as shown in FIG.
As shown in the directional characteristic on the horizontal plane of (a) and the directional characteristic on the vertical plane of FIG. 4 (b), it is possible to transmit ultrasonic waves of high directivity into the sea for each azimuth of 10 degrees. it can.

FIG. 5 is a block diagram showing a configuration of an apparatus included in the buoy 40. The buoy 40 is an antenna 41, GP
S42, main controller 43, transmitting device 44, thruster 45, azimuth meter 46, scanner controller 47, ultrasonic wave transmitter (ultrasonic scanner) 48, distance / information controller 49, ultrasonic wave transmitter 50, ultrasonic wave reception The container 51, the solar cell 55, the power supply unit 56 and the like are provided.

The GPS 42 identifies the geographical position of the buoy 40 based on the GPS signal received by the antenna 41 and outputs it to the main controller 43. Compass 46
Is a device for measuring the azimuth of the buoy 40. For example, among the 36 transducers forming the ultrasonic wave transmitter 48, one predetermined one (the transducer facing the true north) is Detect the pointing direction.

The scanner controller 47 includes an azimuth meter 46.
Transmitting the azimuth information obtained from the main controller 43, and confirming that the buoy 40 is oriented in a predetermined azimuth from the azimuth information, and then sending a constant signal to the ultrasonic transmitter 48. Then, an ultrasonic wave that scans in all directions is transmitted. Specifically, first, by using all the transducers of the ultrasonic wave transmitter 48, an ultrasonic wave including a code indicating true north in all directions (hereinafter, also referred to as “true north signal”). Then, at a fixed time interval, while sequentially using 36 transducers clockwise, the azimuth (clockwise angle from north: 10 degrees, 20 degrees, ...
.., ultrasonic waves (hereinafter, also referred to as "azimuth signal") including a code indicating 350 degrees are sequentially transmitted (scanned)
I will do it. As a result, the submersible boat 20 can specify the azimuth with the buoy 40 as the base point.

The distance / information controller 49 is used for the submersible boat 2
When an ultrasonic wave including the identification code of the submersible boat 20 is received from 0 through the ultrasonic wave receiver 51, after a certain time, the ultrasonic wave is transmitted through the omnidirectional ultrasonic wave transmitter 50 (or the ultrasonic wave transmitter). 48
Ultrasonic wave including the received identification code of the submersible 20 and the identification code of the buoy 40 is returned. As a result, the distance from the buoy 40 in the submersible 20 can be detected. It should be noted that the distance / information controller 49 relates to the azimuth information indicating the azimuth of the submersible 20 from the buoy 40, the distance information indicating the distance from the buoy 40 to the submersible 20, and the water depth information indicating the water depth of the submersible 20. Is also received from the submersible boat 20 via the ultrasonic wave receiver 51.

The main controller 43 determines that the buoy 40 has a fixed geography based on the azimuth information sent from the azimuth meter 46 via the scanner controller 47 and the geographical position information sent from the GPS 42. The thruster 45 is controlled so as to stop at the target position and face a certain direction, and the position information (direction information, direction information, of the submersible 20 sent from the distance / information controller 49 together with the information of this geographical position. Information indicating a relative position such as distance information and water depth information) is transmitted to the base station 60 via the transmission device 44 and the antenna 41 at regular time intervals.

The transmitter 44 is a modulator / amplifier for wireless transmission to the base station 60, and the power supply unit 56 stores the electric power obtained by the solar battery 55 and supplies the electric power to each electronic circuit. It is a circuit to do.

FIG. 6 is a block diagram showing the configuration of the ship position measuring system provided in the base station 60. Base station 60
Is the buoy 40 and submersible boat 20 sent from the buoy 40.
Antenna 61 and receiving device 62 for receiving a signal including the position information of the buoy 40 and the submersible 2
A signal conversion device 63 that demodulates the position information of 0, an underwater display unit 64 that displays a diagram showing the positions of the buoy 40 and the submersible 20 in the sea based on the demodulated position information, and the buoy 4
0 and the horizontal position of the submersible 20 along with a map of the surrounding area and the like, and a horizontal display section 65.

Next, a specific method of detecting the three-dimensional position of the submersible boat 20 in the sea in the position detecting system 10 of the present embodiment configured as described above will be described.

As shown in FIG. 7, the submersible boat 20 has three pieces of position information to be acquired at any time, that is, (1) the water depth of its own ship,
(2) Straight distance from buoy 40 to own ship, (3) buoy 4
The three-dimensional position of the own ship based on the buoy 40 is specified in the sea based on the direction of the own ship based on 0. The submersible boat 20 can know the geographical position of the buoy 40 itself from the identification code of the buoy 40 transmitted from the buoy 40 and the position information (latitude and longitude) obtained by the GPS 42. Further, such position identification is repeated at regular time intervals. This enables real-time position specification.

Hereinafter, a method of acquiring the above three position information will be described in more detail. (1) Water depth of own ship The water depth gauge 21 installed in the submersible boat 20 acquires the water depth of the own ship. (2) The direct distance submersible boat 20 from the buoy 40 to the ship itself receives the ultrasonic waves emitted by itself and reaches the buoy 40.
The distance from the buoy 40 is calculated based on the round-trip time until the buoy 40 returns. Specifically, FIG.
8A is a communication sequence diagram, FIG. 8B is a transmission / reception timing diagram in the submersible boat 20, and FIG. 8C is a buoy 40.
As shown in the timing chart of transmission / reception in FIG. 1, first, the submersible boat 20 transmits a coded ultrasonic wave capable of identifying its own boat in all directions (step S1). The buoy 40 that received the signal and confirmed that it was the signal from the submersible 20
Immediately (after a certain processing time tp) transmits in all directions a signal (ultrasonic wave) obtained by adding its own identification code to the identification code of the submarine 20 just received (step S2).

The submarine 20 that received the signal from the buoy 40
Calculates the time td from the time of transmission to the time of reception, and based on the following equation from the processing time tp stored in the buoy 40 and the propagation velocity s of ultrasonic waves in the sea, which are stored in advance, The distance L from is calculated. L = (td-tp) / s

The processing time tp of the buoy 40 is
If it is extremely smaller than the round-trip time td of the signal, it need not be considered. The ultrasonic wave propagation velocity s may be a fixed value (for example, 1480 m / sec) or a value determined depending on the temperature in the sea at that time. These may be determined according to the required accuracy of the three-dimensional position.

FIG. 9 is a view showing the detailed contents of signals exchanged between the submersible boat 20 and the buoy 40, and FIG.
Shows the data structure of the signal transmitted from the submersible 20, and FIG. 9 (b) shows the data structure of the signal transmitted from the buoy 40. Here, in these two-way communication, a carrier wave (ultrasonic wave) of about 200 kHz (wavelength is 5 μsec) is used, and one pulse (1 bit) width is 2
Information is transmitted and received by digital modulation of about 00 μsec.

As shown in FIG. 9A, the submarine 20
Transmits ultrasonic waves including the following code in all directions at intervals of about 1 second (step S1 in FIG. 8A). (i) Start signal (2 pulse width) (ii) Identification code indicating own ship (8 pulses) (iii) Data indicating the direction of own ship based on buoy 40 (8 pulses) (iv) From buoy 40 Data showing distance to ship (10 pulses) (v) Data showing water depth of own ship (10 pulses) (vi) Stop signal (3 pulse width)

However, if the data of (iii) to (v) above are already known by the communication immediately before with the buoy 40, the acquisition of the direction data from the buoy 40, and the measurement by the water depth gauge 21, the data immediately before The data is included in this signal, and is for notifying the position of the submersible 20 in real time to the base station 60 via the buoy 40.

The buoy 40 receiving this signal is shown in FIG.
As shown in (b), an ultrasonic wave including the following code is immediately returned in all directions (step S2 in FIG. 8A). (i) Start signal (2 pulse width) (ii) Received identification code of submersible boat 20 (8 pulses) (iii) Identification code of buoy 40 (8 pulses) (iv) Stop signal (3 pulse width)

That is, a signal obtained by adding identification data representing the self (buoy 40) to the same signal as the one obtained by omitting the data representing the azimuth and distance included in the signal sent from the submersible boat 20 is transmitted in all directions. To do.

As described above, the submersible boat 20 can identify the distance from the buoy 40 from the round trip time by exchanging a constant ultrasonic signal with the buoy 40. When the distance can be specified, in the next (after 1 second) ultrasonic wave transmission, as shown in FIG. 9A, an ultrasonic wave including data indicating the specified distance is transmitted. (3) Bearing direction of own ship based on buoy 40

The submersible boat 20 includes (i) a code indicating an azimuth in units of 10 degrees after receiving an ultrasonic wave (true north signal) including a code indicating true north emitted at the start of scanning by the buoy 40. Based on the time until the received ultrasonic wave (azimuth signal) is received, and (ii) the code indicating the azimuth included in the received azimuth signal, the azimuth of the ship based on the buoy 40 is specified. Specifically, the communication sequence diagram of FIG. 10A, the transmission / reception (here, transmission only) timing diagram of the buoy 40 of FIG. 10B, and the transmission / reception of the submersible boat 20 of FIG. 10B (here , Reception only), the buoy 40 first uses all 36 transducers that make up the ultrasonic transmitter 48 and includes a code indicating the true north. Sound waves are transmitted in all directions (step S11). Subsequently, at constant time intervals ts, by sequentially using the 36 transducers constituting the ultrasonic wave transmitter 48 in a clockwise direction, a code or the like indicating an angle increasing in 10 degree increments is included. Ultrasonic waves are transmitted (steps S12 to S13 to S14). Specifically, first, 10
Transmit the code indicating the azimuth of 10 degrees using only the transducer corresponding to the degree, and
The scan of transmitting the code indicating the azimuth of 20 degrees using only the transducer corresponding to 0 degrees is repeated for the azimuth of 10 degrees to 350 degrees. When the scan of one rotation is completed, the same scan is repeated again. As a result, as shown in the directional pattern shown in FIG. 4, an ultrasonic wave having a sharp horizontal directional pattern starting from true north and turning clockwise toward the sea at fixed time intervals and azimuths of 10 degrees is generated. It is transmitted sequentially.

On the other hand, when the submersible boat 20 receives the true north signal emitted in all directions (step 11), it starts the timer and then receives the direction signal (step S1).
Measure time Tr until 3). And that time tc
And the previously known time interval Td, the bearing θ of the ship from the buoy 40 as a base point (degree) according to the following formula:
Specify. θ = (tc / ts) · 10

At this time, the submersible craft 20 can directly know the bearing of the own boat from the code indicating the bearing included in the received bearing signal. Therefore, the submersible boat 20 mutually compares the azimuths obtained by these two methods, and after confirming that they match each other, determines the azimuth as the azimuth of the own ship.

Depending on the spread of the azimuth signal transmitted from the buoy 40 in the horizontal directional characteristic, the position of the submersible 20, the sensitivity of the ultrasonic receiver 30b provided in the submersible 20, and the like,
The submersible 20 does not always receive only one type of heading signal. Therefore, when the submarine 20 receives an ultrasonic wave including a plurality of consecutive heading codes,
One azimuth code is specified by adopting the ultrasonic wave having the highest signal strength (and the code indicating the azimuth contained therein).

However, when more accurate position detection is required, the submersible boat 20 can specify a finer azimuth by a calculation process by using a plurality of received azimuth signals. For example, among the received azimuth signals, the one having the largest signal strength and the one having the next largest signal strength are proportionally distributed in accordance with the signal strength, and the like. ) Is treated as received by the ship. For example, when an ultrasonic wave including a code with an azimuth of 130 degrees and an ultrasonic wave including a code with an azimuth of 140 degrees are received with substantially the same intensity, at a time located in the middle of the time when the two ultrasonic waves are received, Assuming that the ultrasonic wave including the code indicating the azimuth of 135 degrees is received, the above azimuth confirmation and confirmation processing is performed.

FIG. 11 is a diagram showing the detailed contents of the azimuth detection signal transmitted from the buoy 40, and FIG.
Shows the data structure of the true north signal transmitted in all directions at the start of scanning (and at the start of another scanning), and FIG. 11B shows the direction transmitted in one direction during scanning. The data structure of a signal is shown. In this transmission, in order to distinguish it from the communication in the above distance measurement, a carrier having a frequency different from the frequency of the carrier used in the distance measurement, for example, 250 kHz (wavelength is 4 μm).
sec) is used as a carrier wave (ultrasonic wave), and information is transmitted and received by digital modulation in which one pulse (1 bit) width is set to about 200 μsec.

As shown in FIG. 11A, the buoy 40
Transmits ultrasonic waves including the following codes in all directions at the scanning start point (step S1 in FIG. 10A). (i) Start signal (3 pulse width) (ii) Buoy 40 identification code (8 pulses) (iii) True north (0 degree) code (10 pulses) (iv) Buoy 40 position specified by GPS 42 ( Data representing latitude) (10 pulses each) (v) Data representing position (longitude) of buoy 40 identified by GPS 42 (10 pulses each) (vi) Stop signal (4 pulse width)

Further, as shown in FIG. 11B, the buoy 40 transmits ultrasonic waves including the following codes for each azimuth during scanning (steps S2 to S2 in FIG. 10A). S3 to S4). (i) Start signal (3 pulse width) (ii) Buoy 40 identification code (8 pulses) (iii) Direction (angle) code (10 pulses) (iv) Stop signal (4 pulse width)

As described above, the submersible craft 20 can specify the bearing with respect to the buoy 40 by receiving the signal indicating the true north and the signal indicating the bearing (angle) transmitted from the buoy 40. it can. When the azimuth can be identified, in the transmission to the buoy 40 for distance measurement, as shown in FIG. 9A, an ultrasonic wave including data representing the identified azimuth is transmitted.

As described above, the present position detection system 1
The submarine 20 at 0 is based on (1) the water depth of its own ship, (2) the straight distance from the buoy 40 to its own ship, and (3) the bearing of the own ship with the buoy 40 as the base point. It is possible to know the three-dimensional position (relative position) of the own ship as the base point. Since the geographical position of the buoy 40 can be known from the latitude and longitude data included in the true north signal transmitted from the buoy 40, the geographical position of the buoy 40 and the relative position from the buoy 40. By adding (3D position) and calculating, the 3D geographical position of the ship can be known.

Further, the relative position of the submersible boat 20 is the same as the submersible boat 2
The base station 60 is notified from 0 through the buoy 40 together with the geographical position of the buoy 40. Therefore, the geographical position of the buoy 40, the three-dimensional relative position and the geographical position of the submersible boat 20 in the sea are merely displayed on the underwater display unit 24 and the GPS horizontal display unit 26 of the submersible boat 20. Without
It is also displayed and monitored on the underwater display unit 64 and the horizontal display unit 65 of the base station 60.

The position detection system according to the present invention has been described above based on the embodiment, but the present invention is not limited to this embodiment. For example, in the present embodiment, the buoy 40 is used as the floating body, but instead of this, it is a marine vessel equipped with a device having a function equivalent to that of the buoy 40, or a sea surface fixed to the seabed or land or It can also be a fixed communication station under the sea. Similarly, the moving body is not limited to the submersible, and may be a portable communication device included in the diver.

Further, in the present embodiment, the buoy 40 controls the thruster 45 on the basis of the azimuth information indicated by the azimuth meter 46 to maintain the buoy 40 in a fixed azimuth direction and to transmit ultrasonic waves. Although the true north signal and the azimuth signal were transmitted from the wave transmitter 48, instead of this, based on the azimuth information indicated by the azimuth meter 46, the ultrasonic wave transmitter 48 was dynamically selected from among the transducers constituting the ultrasonic wave transmitter 48. It is also possible to determine a vibrator that faces the true north and start a true north signal and an azimuth signal using the vibrator as a starting point. This eliminates the need for the thruster 45 to control the buoy 40 in a fixed direction.

Further, in the present embodiment, the ultrasonic wave transmitter 48 composed of a group of 36 transducers arranged radially is used as the scanning means for specifying the direction of the submarine. However, it is also possible to employ a system in which one oscillator or a wave transmitter that sends out ultrasonic waves in one direction is mechanically rotated at a constant speed.

Further, in this embodiment, the position information and the like are transmitted from the submersible 20 through the buoy 40 to the base station 60, but the direction of communication is not limited to this direction, and the base station 60 is not limited thereto. The information such as a command may be transmitted from the vehicle to the submersible boat 20 via the buoy 40. Specifically, the buoy 40 is provided with a wireless communication device for wirelessly communicating with the base station 60, a transducer for bidirectionally converting radio waves and ultrasonic waves, a communication device for ultrasonically communicating with the submersible 20. By doing so, the buoy 40 can function as a communication relay station between the submersible boat 20 and the base station 60. As a result, the submersible boat 20 can communicate with a land-based base station while remaining in the sea without floating on the surface of the sea.

Further, in order to improve the measurement accuracy of the direction of the submersible boat 20 and the like, a function of correcting the dispersion of the measured values due to the shaking of the buoy 40 due to the wave of the sea surface is provided in the buoy 40 or the submersible boat 20. Good. Similarly, even if the accuracy of distance measurement in the submersible 20 is improved by incorporating a calculation process that takes into consideration changes in the propagation velocity of ultrasonic signals in the sea based on the quality of seawater (salt concentration, temperature, etc.). Good.

[0058]

As is apparent from the above description, according to the position detecting system of the present invention, the three-dimensional structure of a moving body such as a submersible boat in the sea can be obtained by merely installing one floating body such as a buoy on the sea. The position can be specified. Therefore, it is not necessary to install a plurality of transponders at accurate positions on the seabed.

Further, the moving body according to the present invention can know the direction from the floating body only by receiving the ultrasonic signal transmitted from the floating body. Therefore, it is not necessary to extend a rod body such as a boom out of the hull of a moving body (submersible) in order to three-dimensionally detect the magnetism from a magnetic marker installed on the seabed, which is safe. .

With respect to the azimuth from the floating body, the moving body according to the present invention indicates the time from the reception of the true north signal transmitted from the floating body to the reception of the azimuth signal and the azimuth included in the azimuth signal. Since the final azimuth is specified by comparing them with the indicated digital value (code), the position of the ship can be accurately determined without being affected by disturbance noise or the like.

Further, the moving body according to the present invention measures the water depth by a water depth meter, specifies the distance from the floating body by transmitting and receiving to and from the floating body by ultrasonic waves, and receives the true north signal and the direction signal transmitted from the floating body. It is possible to know the geographical three-dimensional position of the own ship in real time by repeating the specification of the azimuth and the geographical position of the floating body included in the true north signal transmitted from the floating body at regular time intervals.

Further, according to the position detection system of the present invention, the position information obtained by the moving body is transmitted to the floating body and is wirelessly notified from the floating body to the land-based base station together with the geographical position of the floating body. . Therefore, the base station can know the three-dimensional position of the moving body in real time together with the geographical position of the floating body.

[Brief description of drawings]

FIG. 1 is a diagram showing components of a position detection system for a submersible boat according to an embodiment of the present invention.

FIG. 2 is a block diagram showing a configuration of a position detection device included in the submersible boat.

FIG. 3 is an external view of a buoy.

FIG. 4 (a) shows a directional characteristic of a buoy's ultrasonic wave transmitter on a horizontal plane, and FIG. 4 (b) shows a directional characteristic of its vertical plane.

FIG. 5 is a block diagram showing a configuration of a buoy.

FIG. 6 is a block diagram showing a configuration of a ship position measuring system provided in a base station.

FIG. 7 is a diagram showing a method for identifying a three-dimensional position of a submersible.

FIG. 8 (a) is a diagram showing a communication sequence for specifying the distance from the buoy to the submersible, and FIG. 8 (b) is a timing chart of transmission / reception in the submersible at that time.
(C) is a timing chart of transmission and reception in the buoy at that time.

9A is a diagram showing a data structure of a transmission signal from the submersible in step S1 of FIG. 8, and FIG.
FIG. 9 is a diagram showing a data structure of a transmission signal from the buoy in step S2 of FIG.

FIG. 10 (a) is a diagram showing a communication sequence for specifying the direction of the submersible boat based on the buoy, and FIG. 10 (b).
Is a timing diagram of transmission in the buoy at that time, and (c) is a timing diagram of reception in the submersible boat at that time.

11A is a diagram showing a data structure of a true north signal from the buoy in step S11 of FIG.
FIG. 11B is a diagram showing the data structure of the azimuth signal from the buoy in steps S12 to S14 of FIG.

[Explanation of symbols]

10 Position detection system 20 submersible 21 Water depth gauge 22 Tide meter 23 Gyro Compass 24 Underwater display 25 GPS antenna 26 GPS horizontal display 27 Controller 28, 31 Transmitter / receiver 29 Ultrasonic transmitter 30a, 30b ultrasonic wave receiver 40 buoy 41 antenna 42 GPS 43 Main controller 44 transmitter 45 Thruster 46 compass 47 Scanner Controller 48, 50 ultrasonic transmitter 49 Distance / Information Controller 51 ultrasonic receiver 55 solar cells 56 power supply 60 base stations 61 antenna 62 receiver 63 signal converter 64 Underwater display 65 Horizontal display

   ─────────────────────────────────────────────────── ─── Continued front page    (71) Applicant 502023033             Wakao Atsunobu             Osaka Prefecture Osaka City Joto Ward Sekime 5 chome 4-7-             307 (71) Applicant 502023044             Komizu             4-11-4 Tsukinowamachi, Otsu City, Shiga Prefecture (71) Applicant 594203405             Yahiro Akio             4-17-7 Nishisugamo, Toshima-ku, Tokyo (72) Inventor Masao Yoshitani             4-11-23-2 Ayame Ikenami, Nara City, Nara Prefecture (72) Inventor Sadao Sawai             3-21-6 Shimotakaido, Suginami-ku, Tokyo F-term (reference) 5J062 BB09 CC07 FF04 GG02                 5J083 AA02 AA03 AB14 AC29 AD01                       AD04 AE07 AF18 BA01 DB02                       DB04 DB07

Claims (17)

[Claims] 1. A system for detecting a three-dimensional position of a moving body in water, comprising: a floating body provided above the water and a moving body moving in water, wherein the floating body is a first body transmitted by the moving body. When one ultrasonic signal is received, a transmitting / receiving means for transmitting a second ultrasonic signal indicating a code corresponding to the first ultrasonic signal in all directions after a fixed time, and a third ultrasonic signal indicating a predetermined azimuth direction. And a scanning means for scanning and transmitting the fourth ultrasonic signal having directivity after being transmitted in all directions at a constant rotation direction, at a constant angle and at a time interval, and at a constant time interval in a constant rotation direction. , A scanning means for sequentially transmitting a fourth ultrasonic signal toward a direction in which the moving body changes by a certain angle, and the moving body has a water depth measuring means for measuring the water depth of the moving body and all directions. To the first ultrasonic signal And a distance for measuring the distance from the floating body to the moving body based on the time from the transmission of the first ultrasonic signal by the transmitting means to the reception of the second ultrasonic signal. Measuring means, and receiving the third and fourth ultrasonic signals transmitted by the floating body,
A position detecting system comprising: an azimuth specifying unit that specifies the azimuth of the moving body with the floating body as a base point based on the third and fourth ultrasonic signals. 2. The floating body further comprises position specifying means for specifying a geographical position of the floating body, and position transmitting means for transmitting the specified geographical position to the moving body, wherein the moving body comprises: Based on the water depth specified by the water depth measuring means, the distance measured by the distance measuring means and the azimuth specified by the azimuth specifying means, the relative position of the moving body with respect to the floating body as a base point is specified, and the relative position and the 2. The position detecting system according to claim 1, wherein the geographical position of the moving body is specified from the geographical position of the floating body transmitted by the position transmitting means. 3. The position transmitting means transmits a code indicating the geographical position to the moving body with the third ultrasonic signal, and the moving body is configured to detect the relative position of the moving body and the third ultrasonic wave. From the code indicating the geographical position of the floating body indicated by the signal,
The position detection system according to claim 2, wherein the geographical position of the moving body is specified. 4. The azimuth specifying means determines the azimuth of the moving body based on the floating body, based on the time from the reception of the third ultrasonic signal to the reception of the fourth ultrasonic signal. The position detection system according to claim 1, wherein the position detection system is specified. 5. The scanning means transmits a code specifying a direction for transmitting the fourth ultrasonic signal as the fourth ultrasonic signal, and the direction specifying means receives the third ultrasonic signal. From the time until the fourth ultrasonic signal is received and the code specifying the azimuth indicated by the received fourth ultrasonic signal,
The position detection system according to claim 4, wherein the azimuth is specified. 6. The azimuth specifying means, when receiving two or more fourth ultrasonic signals differing by the certain angle,
The position detection system according to any one of claims 1 to 5, wherein the azimuth is specified by using two of the two or more fourth ultrasonic signals having a large signal intensity. 7. The transmitting means transmits the identification code of the moving body by the first ultrasonic signal, and the transmitting / receiving means uses the identification code indicated by the first ultrasonic signal transmitted by the moving body as the first ultrasonic signal. 2 The ultrasonic wave signal is transmitted, and the distance measuring means receives the second ultrasonic wave signal indicating the identification code after the first ultrasonic wave signal indicating the identification code is transmitted by the transmitting means. 7. The distance is measured based on
The position detection system according to any one of 1. 8. The position detection system includes a base station that monitors the position of the mobile body, and the transmission means measures the water depth specified by the water depth measurement means and the distance measurement in addition to the identification code. The distance measured by the means and the azimuth specified by the azimuth specifying means are transmitted by the first ultrasonic signal, and the floating body further includes an identification code indicated by the first ultrasonic signal received by the transmitting / receiving means, a water depth, The position detection system according to claim 7, further comprising a reporting unit configured to report the distance and the azimuth to the base station. 9. The reporting means reports to the base station the geographical position identified by the location identifying means in addition to the identification code, water depth, distance and azimuth indicated by the first ultrasonic signal. The position detection system according to claim 8. 10. The floating body is a buoy or a ship provided on the sea, and is provided with thrust means for maintaining the geographical position of the floating body specified by the position specifying means. 9. The position detection system according to item 9. 11. The position detection system includes a base station installed on land that communicates with the mobile body, wherein the floating body receives radio waves transmitted from the base station,
7. A relay unit is provided which converts into ultrasonic waves and transmits the ultrasonic waves to the mobile body, receives ultrasonic waves transmitted from the mobile body, converts the ultrasonic waves into electric waves and transmits the electric waves to the base station. The position detection system according to 1 to 7. 12. A method for detecting a three-dimensional position of a moving body in water, comprising: a water depth measuring step of measuring a water depth of the moving body by a water depth meter provided in the moving body; The floating body provided on the water that has transmitted the first ultrasonic signal to the first ultrasonic signal and transmitted the second ultrasonic signal in all directions and has received the second ultrasonic signal. A distance specifying step of measuring a distance from the floating body based on a time from transmitting the first ultrasonic signal to receiving the second ultrasonic signal; and a third step in which the floating body indicates a predetermined azimuth. After transmitting the ultrasonic signal in all directions in water, the fourth ultrasonic signal having directivity is scan-transmitted at a constant rotation direction, at a constant angle and at a time interval, and the moving body transmits the third ultrasonic signal. The fourth ultrasonic signal after receiving And a azimuth specifying step for specifying the azimuth of the moving body with the floating body as a base point based on the time until the reception of the position detection method. 13. The fourth ultrasonic signal indicates a code for specifying the azimuth, and in the azimuth specifying step, the mobile body receives the third ultrasonic signal and then the fourth ultrasonic signal. 13. The position detecting method according to claim 12, wherein the azimuth is specified based on a time required to receive the azimuth and a code specifying the azimuth indicated by the received fourth ultrasonic signal. 14. A floating body provided on water, wherein after transmitting a first ultrasonic signal indicating a predetermined azimuth in all directions, a second ultrasonic signal having directivity is transmitted in a constant rotation direction at a constant direction. A floating body comprising scanning means for scanning and transmitting at an angle and a time interval. 15. The floating body further receives a third ultrasonic wave signal transmitted by a moving body moving in water, and after a certain time, a fourth ultrasonic wave signal indicating a code corresponding to the third ultrasonic wave signal. 15. The floating body according to claim 14, further comprising a transmitting / receiving means for transmitting in all directions. 16. The floating body further comprises position specifying means for specifying a geographical position of the floating body, and position transmitting means for transmitting the specified geographical position to the moving body. 15. The floating body according to item 15. 17. The floating body further includes an orientation of the moving body specified by the moving body based on the first ultrasonic signal and the second ultrasonic signal, the third ultrasonic signal and the fourth ultrasonic signal. Informing means for informing a base station installed on land of the distance between the floating body and the moving body specified by the moving body based on an ultrasonic signal and the geographical position of the floating body specified by the position specifying means. 1. The method according to claim 1, further comprising:
The floating body according to 6.