JPH05302974A - Acoustic positioning apparatus - Google Patents

Abstract

PURPOSE:To easily decide an accurate position from two simultaneously obtained positions of an underwater navigation body by a method wherein a means which measures data in the depth direction is installed additionally on the underwater navigation body. CONSTITUTION:For example, a depth sensor 10 is attached to the outside of a navigation body 3; it senses a water pressure; the resistance of the sensor itself is changed; a change in the resistance is output as a change in a voltage. The output signal of the sensor 10 is A-to-D-converted 11; it is input to an operation and control part 7. Two answers are found from positional coordinates of the navigation body 3. In one answer, distances from a first transponder 2-1 to a third transponder 2-3 are r1 to r3, and the depth is shallow and close to the surface of the sea; in the other answer distances are r'1 to r'3 and the depth is deep and close to the bottom of the sea. They are compared with data on a depth which has been found by means of the sensor 10; the positional coordinates in which data on a position in the depth direction is close to the data on the depth is selected automatically by means of the control part 7. Thereby, the correct positional coordinates are decided. That is to say, one out of two positional coordinates is decided depending on whether the depth of the navigation body 3 is D1 or D2.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an acoustic positioning device for measuring the position of underwater vehicles using underwater ultrasonic waves.

[0002]

2. Description of the Related Art Conventionally, an acoustic positioning device for measuring the position of an underwater vehicle by using underwater ultrasonic waves is a device for transmitting / receiving a wave or a beacon element on a moving body which is a basis for determining a coordinate system. LBL, SBL, and S depending on the length of the interval
There are three types of SBL (USBL) types.

In the LBL type acoustic positioning device, three or more transponders are installed on the seabed, and a direct distance (slant range) r _i (i = _i ) between the transponder of the vehicle and each transponder. 1, 2, 3 ...) are measured to obtain the position coordinates (x _v , y _v , z _v ) of the transducer as viewed from the coordinate system formed by the transponder. The baseline length of this method is considered to be the distance between transponders and can be as long as several kilometers.

FIG. 2 is a functional block diagram of a conventional acoustic positioning device. In the figure, 1 is water, 2-1 to 2-3 are first to third transponders installed on the seabed, 3
Is a vehicle for navigating underwater 1, 4A is a wave transmitter attached to the vehicle 3, 4B is a wave receiver, and 5-1 to 5-3 are first to third Longs installed inside the vehicle. Base Line
A receiver (hereinafter, referred to as “LBL receiver”), 6 is a transmitter, 7 is a calculation control unit, 8 is a display, and 9 is a reference clock.

The operation of the conventional acoustic positioning device will be described below.
To do. First, the time data from the reference clock 9 inside the navigation body 3
In accordance with the data
And repeatedly send a transmission command to the transmitter 6 to perform transmission.
It The output of the transmitter 6 exceeds 1 in water via the transmitter 4B.
Send a sound pulse. This ultrasonic pulse is the interrogation signal
To reach the first to third transponders 2-1 to 2-3
Each transponder has a different
Frequency f₁, F ₂, F₃(For example, f₁= 15 kHz,
f₂= 16 kHz, f₃= 17 kHz) acoustic response signal
To send. First to third transponders 2-1 to 2-3
The acoustic response signals respectively transmitted from the
After being received and converted to an electric signal, the first to third L
It is received by the BL receivers 5-1 to 5-3. Each LB
In the L receivers 5-1 to 5-3, the arithmetic control unit 7 sends a transmission command.
Until the transponder response signal is detected after output.
Time (i.e., the ultrasonic pulse is
From the time it takes to travel back and forth between the spawners)
Direct distance to the spawner 2 (also called slant range)
Measure). That is, the first LBL receiver is
Frequency f transmitted from the transponder 2-1₁Response
No. received and its direct distance r₁To measure. Also, the second L
BL receiver transmitted from the second transponder 2-2
Frequency f₂Received the response signal of the₂Measure
To do. Similarly, the third LBL receiver is the third transponder.
Frequency f transmitted from 2-3 ₃Received the response signal of
Its direct distance r₃To measure. These measured direct distances
r₁~ R₃Data from each LBL receiver to the arithmetic control unit 7
Is supplied to. First to third transponders 2-1 to 2-1
By the work called calibration, the position coordinates of 2-3 are
Then, the position coordinates of the running body 3 are first to third.
Direct distance r from transponders 2-1 to 2-3₁~ R₃
Calculated as the intersection of

Positional coordinates (x _v , y _v , z _v ) of the vehicle 3
Is calculated by the following formula. In Fig. 2, three transponders are installed on the seabed, and their position coordinate values (x
It is assumed that _i , y _i , z _i , i = 1, 2, 3) have been determined by calibration for the work. Vessel 3
For one transmission of the interrogation signal of the transmitter / receiver of, the measurement result of the three direct distances represented by the following equation is obtained.

R _i ² = (x _v −x _i ) ² + (y _v −y _i ) ² + (z _v −z _i ) ² i = 1,2,3 x _v , y _v , z _v are unknowns. The position coordinates of the running body 3 are calculated by solving the above simultaneous equations.

[0008]

However, in the above-mentioned conventional acoustic positioning device, calculation is performed to find the intersections of the direct distances r _{1 to} r ₃ from the positions of the first to third transponders 2-1 to 2-3. And the first to third transponders 2-1
A solution representing the position coordinates of the two vehicles is obtained above and below the plane connecting ~ 2-3.

Next, the point where two solutions of the position coordinates of the vehicle are obtained will be described. FIG. 3 is a diagram showing the relationship of position coordinates that determine the position of the vehicle. In the figure, a, b,
Reference numeral c indicates a reference position corresponding to the first to third transponders, and the position coordinates of the vehicle are obtained based on the position coordinates of this point. When the distance from the reference position a to r _1, the position of the distance r ₁ is the sphere A of the radius r ₁ around the reference position a. The distance from the reference position b is r ₂
When a sphere B next to the radius r ₂ position of the distance r ₂ is centered on the reference position b, and the a r ₃ distance from Likewise the reference position c, the position reference position c of the distance r ₃ It becomes a sphere C having a radius r ₃ centered on the center. Here, considering the intersection of the sphere A and the sphere B, the sphere A and the sphere B intersect in a circle represented by D in the figure. That is, a point located at the distance r ₁ from the reference position a and at the same time located at the position r ₂ from the reference position b exists on the circle D.

Considering the intersection of sphere B and sphere C, sphere B and sphere C intersect in the circle indicated by E in the figure. That is, a point located at the distance r ₂ from the reference position b and at the same time located at the position r ₃ from the reference position c exists on the circle E. Similarly, considering the intersection of sphere C and sphere A, sphere C and sphere A intersect in the circle represented by F in the figure. That is, a point located at the distance r ₃ from the reference position c and at the same time located at the position r ₁ from the reference position a exists on the circle F. These three circles D, E,
The intersection of F is performed at two points, point d and point e in the figure.
Therefore, it is located at the distance r ₁ from the reference position a, at the position r ₂ from the reference position b, and at the same time at the position r ₃ from the reference position c, the point d where three spheres intersect is present. And point e.

Therefore, when the reference position is made to correspond to the first to third transponders, there are two possibilities for the position of the vehicle which is determined by the distance from the three reference positions. Further, in order to make this positional relationship easy to understand, it will be described in two dimensions. FIG. 4 is a two-dimensional representation of the above positional relationship.

Assuming that the reference position is g and h, the position at a constant distance from the reference position g is a circle G, and the position at a constant distance from the reference position h is a circle H. Then, considering the point where these two circles intersect, they intersect at the points i and j. Both the intersections i and j have the same reference positions as the reference positions g and h, and it is impossible to determine which position is the position where the vehicle exists as it is.

Conventionally, there is a method of selecting one of the above two positions by adding one transponder and obtaining it by four direct distances. However, this method is complicated in calculation and one transponder must be added. This causes the devices for arithmetic processing to become complicated and large, and it is difficult to install these devices on a vehicle whose size is limited. In addition, the addition of transponders is expensive for the transponders themselves, which leads to an increase in the number of calibration operations after installation, which makes the entire system expensive. Therefore, the method of adding one transponder and obtaining the four direct distances has many problems.

Another way of choosing which of the two positions is to determine whether the vehicle is above or below the plane of the triangle formed by the three transponders. There is a method for a person to visually judge. However, this method has a problem in that it is difficult to judge because the field of view from the vehicle is narrow, and the vehicle itself is not fixed at a fixed position but floats. In the vicinity, it is impossible to visually judge because the visibility is obscured by the seabed sediments and other floating materials in the water that are dark and soaring.

The present invention solves the problems of the conventional acoustic positioning apparatus described above, and makes it possible to add a large-scale facility such as a transponder, and to complicate or increase the size of the arithmetic processing apparatus, thereby reducing the size of the apparatus. It is an object of the present invention to determine one of two positions of a vehicle at the same time obtained by the device and a simple process to perform accurate positioning.

[0016]

In order to achieve the above-mentioned object, in the acoustic positioning device of the present invention, means for transmitting an acoustic interrogation signal, means for receiving an acoustic response signal, and measurement of data in the depth direction. And a transponder means that is installed in the underwater positioning area and that receives the acoustic interrogation signal and transmits acoustic response signals of different frequencies. An acoustic positioning device configured to measure a position coordinate of a running body by a direct distance from the transponder means obtained by the acoustic response signal and the data in the depth direction.

[0017]

According to the present invention, since the acoustic positioning device is configured as described above, the position coordinates of the vehicle can be measured by the direct distance from the transponder means obtained by the acoustic response signal, and the depth direction can be measured. Since the optimum one is selected from the position coordinates of the vehicle based on
Accurate position coordinates can be measured without adding large-scale equipment.

[0018]

Embodiments of the present invention will now be described in detail with reference to the drawings. FIG. 1 is a functional block diagram of the acoustic positioning device according to the first embodiment of the present invention. In the figure, 1
Is underwater, 2-1 to 2-3 are first to third transponders respectively installed on the seabed, 3 is a running body, 4A is a transmitter,
4B is a wave receiver, 5-1 to 5-3 are first to third LBL receivers installed inside the vehicle, 6 is a transmitter, 7 is an arithmetic control unit, 8 is an indicator, and 9 is a reference clock. 10 is a depth sensor, 1
Reference numeral 1 is an analog / digital converter (hereinafter referred to as an A / D converter). The wave transmitter 4A is connected to the arithmetic control unit 7 via the transmitter 6, while the wave receiver 4B is connected to the arithmetic control unit 7 via the first to third LBL receivers 5-1 to 5-3. There is. The first to third LBL receivers 5-1 to 5-3 are also connected to the transmitter 6. The depth sensor 10 is connected to the arithmetic control unit 7 via the A / D converter 11. A display 8 and a reference clock 9 are also connected to the arithmetic and control unit 7. Therefore, the arithmetic control unit 7 includes the first to third L
Information regarding the reception signal of the wave receiver 4A and the depth of the depth sensor is input via the BL receivers 5-1 to 5-3 and the A / D converter 11. Further, the arithmetic control unit 7 includes a reference clock 9
The time data is input from. On the other hand, the arithmetic control unit 7 outputs a transmission command to the transmitter 6 and the first to third LBL receivers 5-1 to 5-3, and the display 8 outputs information regarding the position coordinates of the vehicle. .. These acoustic positioning devices are installed in the running body 3.

Next, the operation of the acoustic positioning device according to the first embodiment of the present invention will be described with reference to the drawings. First, according to the time data from the reference clock 9 inside the running body 3,
A transmission command is repeatedly given to the transmitter 6 at regular intervals from a certain reference time, and the transmitter 6 emits a transmission pulse. The transmission pulse from the transmitter 6 drives the transmitter 4B and
To send an ultrasonic pulse to. This ultrasonic pulse is transmitted as an interrogation signal to the first to third transponders 2-1 to 2-3. When the first to third transponders 2-1 to 2-3 receive the ultrasonic pulse of the interrogation signal, the transponders 2-1 to 2-3 have different frequencies f ₁ , respectively.
The acoustic response signals of f ₂ and f ₃ are transmitted. The acoustic response signals from the transponders 2-1 to 2-3 are transmitted to the wave transmitter 4
After the interrogation signal is issued from B, it is issued after a delay time corresponding to the distance between the vehicle 3 and each transponder. The acoustic response signals respectively transmitted from the first to third transponders 2-1 to 2-3 are received by the wave receiver 4A and converted into electric signals, and then the first to third LBL receivers 5-1 to 5-1. 5-3 received. Each of the LBL receivers 5-1 to 5-3 measures the direct distance to the transponder by the time interval from when the arithmetic control unit 7 outputs the transmission command to when the response signal of the transponder is detected.

That is, the time intervals from when the arithmetic control unit 7 outputs the transmission command to when the LBL receivers 5-1 to 5-3 detect the response signals of the corresponding transponders are the same as those of the running body 3 respectively. It corresponds to a distance twice as large as that of the transponder, and the direct distance can be measured by the received signal of each LBL receiver. First LBL receiver 5-
1 is the frequency f transmitted from the first transponder 2-1.
The response signal of ₁ is received, and its direct distance r ₁ is measured. Also, the second LBL receiver 5-2 is the second transponder 2-
The response signal of frequency f ₂ transmitted from ₂ is received, and the direct distance r ₂ is measured. Similarly, the third LBL receiver 5-
3 is the frequency f transmitted from the third transponder 2-3
The response signal of ₃ is received, and the direct distance r ₃ is measured. The measurement of the direct distance r in the LBL receiver 5 is performed by counting the time interval with a counter or the like. That is, the arithmetic and control unit 7 starts counting the counter by the transmission command output from the transmitter 6, and stops the counting by the reception of the response signal from the LBL receiver 5. Two
The time interval corresponding to the doubled distance is measured, and the direct distance is calculated from the time interval.

The data of the measured direct distances r _{1 to} r ₃ are sent from the LBL receivers 5-1 to 5-3 to the arithmetic control unit 7.
Is supplied to. First to third transponders 2-1 to 2-1
2-3 position coordinates (x _i , y _i , z _i , i = 1, 2,
3) If you leave determined by task of calibrating the position coordinates of Kohashikarada _{3 (x v, y v,} z v) straight distance r ₁ from the first to third transponder 2-1 to 2-3
It is calculated as the intersection of ~r _3.

On the other hand, the depth sensor 10 is for measuring the depth of the running body in water, and is attached to the outside of the running body 3, for example, and feels water pressure to change the resistance of the sensor itself to change its resistance. Is output as a voltage change. The output signal of the depth sensor 10 is the A / D converter 11
The analog voltage value corresponding to the depth is converted into a digital value and input to the arithmetic control unit 7.

In the first to third LBL receivers 5-1 to 5-3
Of the first to third transponders 2-1 to 2-3 received
Direct distance r depending on response signal₁~ R₃Measure the direct distance
Separation r ₁~ R₃Data and calibration beforehand
First to third transponders 2-1 to 2-1 determined by
And the position coordinate of -3, the direct distance r₁~ R₃Intersect
When the position coordinates of the position are calculated, it will be explained with reference to FIGS.
Connect the first to third transponders 2-1 to 2-3 as described above.
The upper and lower positions with respect to the plane
Two solutions are required.

That is, of the two solutions in FIG. 1, one of the position coordinates has the first to third transponders 2-1 to 2-.
3 is r _1, r _2, r ₃ and has a shallow depth and is close to the sea surface, and the other position coordinate is r ₁ from the first to third transponders 2-1 to 2-3. ' _, r ₂ '
_, r ₃ ' It is deep and close to the sea floor.

The position coordinate of either one of these is used for the moving body 3
Whether to select as the position of is performed as follows. The depth data input from the depth sensor 10 via the A / D converter 11 is compared with the position data in the depth direction of the position coordinates obtained above, and the position data in the depth direction is closer to the depth data. The position coordinates are determined by the arithmetic control unit 7 automatically selecting. That is, one of the two position coordinates is determined depending on whether the obtained value of z _v of the position coordinate is D ₁ or D ₂ of the depth of the running body 3.

Next, an acoustic positioning device according to a second embodiment of the present invention will be described with reference to FIG. In the configuration of the acoustic positioning device of the second embodiment of the present invention, a means for measuring the distance from the seabed is provided instead of the depth sensor of the acoustic positioning device of the first embodiment of the present invention. In the figure, in the acoustic positioning device of the first embodiment of the present invention, the depth from the sea surface of the vehicle is measured by a depth sensor that senses water pressure and changes the resistance of the sensor itself and outputs the resistance change as a voltage change. However, the position coordinates of the vehicle are determined by the depth, but the acoustic positioning device of the second embodiment of the present invention determines the position coordinates of the vehicle by measuring the distance from the seabed. Is.

The distance D ₃ from the seabed of the running body is measured by, for example, emitting a sound wave from the running body to the seabed and measuring the time until the reflected sound reaches the running body again. Can be done by Distance from this seabed D ₃
Then, one of the two position coordinates is determined in the same manner as the acoustic positioning device according to the first embodiment of the present invention from the known seabed depth near the position.

The present invention is not limited to the above-mentioned embodiments, but can be variously modified within the scope of the present invention, and they are not excluded from the scope of the present invention.

[0029]

As described above in detail, the present invention has the following effects. (A) One of them can be determined from the data obtained in the depth direction from the two positions of the vehicle at the same time, and accurate positioning can be performed. (B) Since it is not necessary to add a large-scale facility such as a transponder, and there is no need to complicate or increase the size of a device for arithmetic processing, it is possible to downsize the device and simplify the processing. (C) Since it does not depend on human vision, there is no unstable judgment due to a narrow field of view or floating floating bodies, and there is no limit to the visibility of sediments on the seabed or other floating materials in water, and accurate positioning is performed. be able to.

[Brief description of drawings]

FIG. 1 is a functional block diagram of an acoustic positioning device according to first and second embodiments of the present invention.

FIG. 2 is a functional block diagram of a conventional acoustic positioning device.

FIG. 3 is a diagram showing the relationship of position coordinates that determine the position of the navigation vehicle of the present invention.

FIG. 4 is a two-dimensional representation of the relationship of position coordinates that determine the position of the vehicle of the present invention.

[Explanation of symbols]

 1 Underwater 2 Transponder 3 Moving body 4A Receiver 4B Transmitter 5 LBL receiver 6 Transmitter 7 Arithmetic control part 8 Display 9 Reference clock 10 Depth sensor 11 A / D converter

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor ▲ Takahashi Hideyuki 1-7-12 Toranomon, Minato-ku, Tokyo Oki Electric Industry Co., Ltd.

Claims (4)

[Claims] 1. (a) means for transmitting an acoustic interrogation signal;
(B) A vehicle having means for receiving acoustic response signals, (c) means for measuring data in the depth direction, (d) means for calculating position coordinates, and (e) positioning area in water. A plurality of transponder means for receiving the acoustic interrogation signal and transmitting the acoustic response signals of different frequencies, respectively, and (f) a direct distance from the transponder means obtained by the acoustic response signal. An acoustic positioning device, characterized in that the position coordinates of the running body are measured based on the data in the depth direction. 2. The acoustic positioning device according to claim 1, wherein the means for measuring the data in the depth direction is a depth sensor for measuring a distance from the water surface. 3. The acoustic positioning device according to claim 1, wherein the means for measuring the data in the depth direction is a sensor for measuring a distance from the water bottom. 4. The acoustic positioning device according to claim 1, 2 or 3, wherein the means for calculating the position coordinates includes an LBL receiver.