JPH0437389B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a motion-reducing sonar device that prevents the mixing of echo signals from unnecessary directions due to the motion of a ship.

[Conventional technology]

An echo signal obtained by transmitting sound waves and scanning a receiving beam for detecting schools of fish, etc. is stored in a memory circuit, and a signal obtained by repeatedly reading out the memory contents of the memory circuit is displayed on a display. A sonar device that displays information is disclosed in JP-A-56-162068, etc. An example of such a sonar device is a sonar device that uses a transducer in which ceramic or ferrite elements are arranged in an arc shape. At the time of wave transmission, all or part of the above elements are excited by the electric power of the sound wave, and the sound wave beam is transmitted to a predetermined sector. When receiving echoes, the amplitude and phase of the echo signals received by the above elements are adjusted and synthesized to obtain a sharp receiving beam, and the above elements are sequentially scanned. , a sharp receiving beam is scanned within a predetermined sector.

After storing the echo signal captured by scanning the receiving beam described above in the memory circuit, in order to display the echo image on the cathode ray tube, the address for reading the echo signal and the address for reading it in the memory circuit are set in the memory circuit. control so that the relative position of the object that caused it is displayed on the cathode ray tube.

When using the above-mentioned sonar device to detect schools of fish, etc., the vibration of the fishing boat due to waves, that is,
Due to the motion caused by the bitching and rolling of the hull, the direction of the above-mentioned receiving beam fluctuates, causing the position of the echo image on the cathode ray tube to fluctuate, and the images of the seabed and waves to be mixed in, making it difficult to identify schools of fish, etc. It often becomes.

As a means to remove echo signals in the direction of oscillation, only when a predetermined single inclination angle and the inclination angle of the hull match,
Japanese Patent Application Laid-Open No. 53-64060 discloses a device that uses a means for transmitting sound waves so that echo signals from the direction of oscillation are not obtained in the receiving beam and thereby removing them.

[Problem to be solved by the invention]

In the above-mentioned means for removing echo signals in the direction of oscillation, the speed of sound waves is slow (the propagation speed in water is 1500 m/s, and it takes a round trip time for the reflected waves to return. (It takes about 1 second to get an echo signal from a school of fish just 750m away), so even if the receiving beam deviates slightly from the normal direction due to agitation, the receiving beam will not be transmitted and will return to the normal direction. Sometimes no echo signal is obtained, and even if the beam is transmitted in the normal direction, by the time the echo signal returns, the received beam has already been directed in another direction due to the oscillation. Since it is not possible to receive echo signals from a school of fish, etc., which has been obtained with great effort, there arises the inconvenience that a school of fish that is clearly within the detection range is missed.

Therefore, there is a problem in that it is expected to provide a device that eliminates these inconveniences with a simple configuration.

[Means to solve the problem]

The present invention stores echo signals obtained by transmitting sound waves as described above and changing the direction of a receiving beam for detecting schools of fish, etc. in a memory circuit, and repeatedly reads out the contents of the memory circuit. In the motion removal sonar device, the signal obtained by the motion is given to a display and displayed, and the echo signal from the direction of motion is removed by the signal obtained by detecting the motion of the boat. means for detecting the amount of oscillation based on the amount of oscillation, means for setting an angular range of a predetermined amount for the amount of oscillation, and only when the amount of oscillation exceeding the set angular range is detected, the echo signal is not taken into the storage circuit. The above-mentioned problem can be solved by providing a control means for preventing the memory contents of the memory circuit from being updated by an echo signal.

〔Example〕

Examples will be described below with reference to the drawings.

In Fig. 1, reference numeral 1 denotes a transducer, which is made up of a large number of elements, assembled into an arc shape as shown in the figure, and connected by lead wires 101 of the elements to a transmitting circuit indicated by 5 and a receiving circuit indicated by 6. connected to the circuit. The transducer 1 is made to protrude into the water from the bottom of the ship and transmits and receives sound waves.

Although the lead wire 101 is not shown in the figure, in the actual device, the lead wire 101 is connected to the rotating shaft shown by 2 or 3.
The wire is routed through the axis of the tilt angle shaft shown in . Further, the transducer 1 is housed in a waterproof dome called a radome.

When a transducer made of elements arranged in an arc shape is excited with power of substantially the same phase and amplitude, sound waves are transmitted substantially uniformly to a sector centered on the transducer 1. This wave is transmitted by the transmitting circuit 5
The pulsed power is converted into sound waves that propagate through the water, and the pulse width and firing interval are determined so that the echoes that return after hitting an object can be identified.

When receiving echoes, the phase and amplitude of the echoes induced in each element are adjusted to create sharp directivity as if each element were arranged on a plane. Then, by sequentially switching the elements used for wave reception by the scanning circuit included in the receiving circuit 6, the sharp directivity is rotated to the range of the sector.

In sonar devices, the above rotation is called scanning.

201 is a turning motor of the turning shaft 2, 301
is the tilt angle motor of the tilt angle shaft 3, and the swing angle (horizontal direction) and tilt angle (vertical direction) of the transducer 1 are directed in the direction desired to be detected by the swing and tilt angle control circuit shown at 4.

7 is a transmission/reception control circuit, which includes a transmission circuit 5 and a reception circuit 6.
In addition to controlling the transmission timing, turning and inclination angle of an echo signal storage control means for controlling the above, and a means for preventing the memory contents of the main memory circuit 10 from being updated by the echo signal only when an amount of vibration exceeding the predetermined angular range is detected. A memory update control means for controlling the memory update control means is provided.
The speed of sound waves in water is approximately 1,500 meters per second, so while receiving echoes within the distance required for detection, for example, if the detection distance is 750 meters, the repetition rate of the wave should be set at 1 second or more. It is necessary to maintain When the transmitting circuit 5 finishes transmitting waves, the receiving circuit 6 starts operating.

As described above, the echo signals appearing on the lead wires 101 of each element of the transducer 1 are synthesized by the amplifier and phase shifter in the receiving circuit 6 so that the phases and amplitudes of the echo signals appearing on each lead wire 101 of the elements of the transducer 1 are approximately equal. do. Then, by switching the above-mentioned amplifier to progressive mode, the sharp receiving beam is scanned.

If the frequency of the sound wave is several tens of kilohertz, the above scanning is performed at several hundred hertz. The oscillation sensor shown at 8 is a so-called inclinometer, such as a rotary shaft of a variable resistor attached to the fulcrum of a rod from which a weight is suspended, and is subjected to oscillation in almost the same way as transducer 1. By placing it in place,
Detect the amount of agitation. For example, the value of the variable resistor increases in response to agitation, and its resistance value indicates the amount of agitation.

In the present invention, the amount of oscillation described above is applied to the transmission/reception control circuit 7, but when an amount of oscillation greater than a predetermined amount of oscillation is applied, for example, an amount of oscillation of ±5 degrees or more, When an amount of oscillation exceeding the angular range set by the angular range setting means that sets a predetermined angular range as the amount of oscillation is applied, an echo signal to be applied from the receiving circuit 6 to the main memory circuit 10 is transmitted as described above. The echo signal storage means, that is, the transmission and reception control circuit 7 erases the echo signal, or the above-mentioned memory updating means, that is, the transmission and reception control circuit 7 controls so that the stored contents of the main memory circuit 10 are not updated.

By this operation, according to the above example, only the echo signal when the oscillation is ±5 degrees or less is stored in the main memory circuit 10, and the cathode ray tube modulation shown at 11 is stored in the main memory circuit 10. added to the circuit. In other words, a predetermined angular range is set for the amount of sway, and only when the amount of sway exceeding this angular range is detected,
By preventing echo signals from being stored in the main memory circuit 10 or by controlling the memory contents of the main memory circuit 10 from being updated by the echo signals, echo signals from unnecessary directions can be stored in the main memory. This prevents it from being mixed into the memory contents of the circuit 10.

Although not shown, the vibration sensor 8 is connected to the rotating shaft 2 directly or indirectly through a gear, etc., and the amount of vibration in the direction of the sector to which the transducer 1 is directed is detected, and the transmission/reception control circuit 7 Alternatively, in addition to one or both of the main memory circuits 10, it is possible to update and store in the main memory circuit 10 only the echo signals when the vibration is less than a predetermined amount, similarly to the above.

Reference numeral 9 denotes a memory address control circuit, which is controlled by the display address control circuit shown at 12 and the transmission/reception control circuit 7, and generates an echo on the cathode ray tube shown at 14, with the transducer 1 as the origin. The address of the main memory circuit 10 for correctly displaying the relative position of the object is determined.

It goes without saying that the echo signal of the receiving circuit 6 is stored in the main memory circuit 10 after being converted into a digital signal as is well known. The main memory circuit 10 is repeatedly read and a read output is output.

The cathode ray tube modulation circuit indicated by 11 converts the output of the main memory circuit 10 into an analog signal, amplifies it, and modulates the density of the electron beam of the cathode ray tube 14. That is, the level of the echo signal is determined so that a strong echo signal creates a dense electron beam, and the object that caused the echo is displayed in a bright image.

If a color cathode ray tube is used as the cathode ray tube 14, the output of the main memory circuit 10 is divided according to intensity and modulated to the three primary color electron guns of the color cathode ray tube, so that the intensity of the echo signal corresponds to the color.

This technology is called color matrix and is widely used in color television. In this case, if the strong echo signal is made into a red image, the medium-intensity echo signal is made into a yellow image, and the weak echo signal is made into a color image close to green, the intensity of the echo can be easily recognized by the human eye.

The cathode ray tube deflection circuit 13 converts the output of the display address control circuit 12 into an analog value corresponding to the irradiation position of the electron beam on the cathode ray tube 14.
This is a circuit for deflecting the electron beam to the relative position of the object that generated the echo signal.

This deflection is performed by underwater deflection power and vertical deflection power supplied from the deflection circuit 13 to orthogonal deflection coils provided on the cathode ray tube 14. The position of the echo signal output from the receiving circuit 6 is recognized by the angle and distance within a predetermined fan-shaped sector with the transducer 1 as the origin. That is, the receiving beam is scanned in the angular direction of the sector,
By measuring the arrival time of the returning echo, the position of the object that produced the echo within the sector can be confirmed.

In this way, when obtaining the deflection of the electron beam of the cathode ray tube 14 corresponding to the angular scanning of the sector using the horizontal and vertical deflection powers described above, a conversion circuit from polar coordinates to rectangular coordinates is incorporated in the address control circuit 9. is necessary.

The scanning of the receiving beam in the sector described with reference to FIG. 1 is also called spiral scanning, and the deflection by the horizontal and vertical deflection coils of the cathode ray tube 14 is as follows:
Also called raster scanning.

Therefore, the address control circuit 9 performs address control such that the position of the echo signal received by spiral scanning is displayed on the display surface of the cathode ray tube 14 by raster scanning, and the relative position of the object that generated the echo is displayed. This is what we do.

In Fig. 2, 15 is the display surface of the cathode ray tube, 1
6 is the range of the image, and 17 is the origin of the image, which corresponds to the position of the transducer 1. The image in the image range 16 is substantially from the image origin 17 to the image range 1.
6 and the angle from the center 22 of the sector.

Such displays are generally Planar Position Indicators (PPI)
However, in the present invention, the tilt angle motor 30
When the angle of inclination of the transducer 1 is tilted obliquely from the horizontal due to the rotation of the transducer 1, the image is obtained by flattening the surface of the inclined angle of inclination.

Reference numeral 18 shows an image of waves at a short distance, and 19 shows an image of a school of fish. However, when the transducer 1 is installed on a ship, the wave image 18 shows an image of a school of fish 19 at a position on the ship. Varies depending on pitching and rolling.

That is, when the sector to which the transducer 1 is directed is toward the sea surface, the image of waves appears over a long distance as shown at 21, and the image of the school of fish becomes unclear as shown at 20.

In the present invention, by limiting the output of the agitation sensor 8, it is possible to select and image only the echo signals arriving from the target inclined surface underwater, so objects such as the image 19 of a school of fish can be clearly visualized. can be recognized.

〔Effect of the invention〕

According to the present invention, as described above, only when an amount of oscillation exceeding a predetermined angular range is detected, the echo signal is prevented from being taken into the memory circuit, and the memory contents of the memory circuit are not updated by the echo signal. As a result, the memory of echo signals such as fish school echoes that were detected and memorized last time is not erased, and the main memory circuit contains echo signals that were detected during the intervals between movements. Since the memory contents can be obtained, the entire detection situation can be displayed without any loss using a very simple and inexpensive configuration that simply adds detection of vibration exceeding a predetermined range and control to prevent update of the memory circuit. It has the advantage of being able to be provided as a physical product.

[Brief explanation of drawings]

FIG. 1 shows the configuration of the main part of the present invention. FIG. 2 shows an example of displaying an echo signal according to the present invention. DESCRIPTION OF SYMBOLS 1...Transducer, 2...Swivel shaft of transducer, 3...Incline shaft of transducer, 4...Angle control circuit for rotation and inclination angle, 301...Incline angle motor, 201...Swivel motor, 5... Transmission circuit, 6... Receiving circuit, 7... Transmission/reception control circuit, 8... Shake sensor, 9... Memory address control circuit, 10... Main memory circuit, 11...
Braun tube modulation circuit, 12...Display address control circuit, 13... Braun tube deflection circuit, 14
...Cathode ray tube, 15...Display surface of cathode ray tube,
16... Range of the image, 17... Origin of the image corresponding to the position of the transducer, 18... Image of nearby waves, 19... Image of the school of fish, 20... Image of the school of fish expanded by the agitation. Image, 21... Image of waves caused by agitation, 101... Element lead line, 22... Center of sector.

Claims (1)

[Claims] 1. An echo signal obtained by transmitting sound waves and changing the direction of a receiving beam for detecting schools of fish, etc. is stored in a memory circuit, and the contents of the memory circuit are repeatedly read out. A motion removal sonar device that displays the obtained signal on a display and removes the echo signal from the direction of motion using the signal obtained by detecting the motion of the boat, comprising: a. (a) an angular range setting means for setting a predetermined angular range for the amount of agitation; (c) only when the amount of agitation exceeding the angular range is detected; An apparatus characterized by comprising: echo signal storage control means for performing control to prevent echo signals from being stored in the storage circuit. 2. The device according to claim 1, wherein: (a) the receiving beam is scanned in a sector, and the sector comprises a transducer that forms the receiving beam and is rotated by a rotating shaft. scanning transducer pivoting means; b. agitation sensor coupling means for detecting the agitation in the direction of the sector directed by the transducer by coupling a movement sensor used in the agitation detection means to the rotation shaft; A device characterized by: 3. The device according to claim 1,
An apparatus characterized by comprising the angular range setting means that sets the angular range to approximately ±5 degrees. 4. An echo signal obtained by transmitting sound waves and changing the direction of a receiving beam for detecting schools of fish, etc. is stored in a memory circuit, and the signal obtained by repeatedly reading out the memory contents of the memory circuit is displayed. A motion removal sonar device that detects and displays the motion of the ship and removes the echo signal from the direction of the motion using a signal obtained by detecting the motion of the ship, comprising: a. (b) angular range setting means for setting an angular range of a predetermined amount for the amount of oscillation; (c) only when the amount of oscillation exceeding the angular range is detected; An apparatus characterized by comprising: memory update control means for performing control to prevent updating by the echo signal. 5. The device according to claim 4, wherein: (a) the receiving beam is scanned over a sector, and the sector comprises a transducer that rotates a transducer that forms the receiving beam by a rotating shaft. scanning transducer pivoting means; b. agitation sensor coupling means for detecting the agitation in the direction of the sector directed by the transducer by coupling a movement sensor used in the agitation detection means to the rotation shaft; A device characterized by: 6. The device according to claim 4,
An apparatus characterized by comprising the angular range setting means that sets the angular range to approximately ±5 degrees.