JPS60203875A - Display method of scanning sonar - Google Patents

Abstract

PURPOSE:To grasp easily the change of an objective position with the passage of time by recording the distance information of the ship's side direction and depth information in a recording means every fixed number of probes or the number of probes corresponding to a ship's speed and displaying the change of these information with the passage of time on the basis of a picture sending method. CONSTITUTION:The position of a detected fish group is calculated by a writing address circuit 15 on the basis of a bearing angle signal from a scanning signal generator 14, a depression angle signal from a depression angle signal generator 23 and a distance signal generated in the writing address circuit 15 and converted at its address and the converted data are sent to a storage circuit 17. A fish group signal from an A/D converter 16 is stored in an address designated by the address information and the stored information is shifted every fixed number of probes or the number of probes corresponding to the ship's speed on the basis of a distance signal from a distance signal generator 12 and supplied to a CRT display device 22 through a D/A converter 19.

Description

DETAILED DESCRIPTION OF THE INVENTION (Technical Field of the Invention) The present invention is a scanning sonar using a fan beam, which calculates distance information and depth information in the broadside direction of a target from detection information for each search. A method of recording each necessary exploration and displaying changes over time in the distance and depth in the broadside direction using an image feed method will be used.

(Prior art and problems) Conventionally, exploration by scanning sonar using a fan beam is performed using a semicircular fan beam in an arbitrary direction with a constant depression angle, as shown in Figure 1. shows an example in which the fan beam is directed toward the bow with an angle of depression φ.

) In the diagram, 1 is a ship equipped with scanning sonar, 2
is a fan beam, 3 is a school of fish (also referred to as a target) captured by the fan beam 2, and 4 is a coordinate axis (χ axis) in the side direction with the origin at the position of the ship l.

Port side is negative and starboard side is positive. The same applies to the following Noh diagrams. ), 5 is the coordinate axis in the direction of travel with the origin at the position of the ship 1 (seven axes. The front is positive and the rear is negative. The same applies to the figures below), T is the direct distance to the target, φ is the depression angle of the fan beam, and θ is the azimuth angle of the target 3 on the two planes of the fan beam with respect to the χ axis.

FIG. 2 is an image on a cathode ray tube (hereinafter referred to as Cr (T)) display of the target detected as shown in FIG. 1.
′ is the target image. The image in FIG. 2 is not a projection onto a horizontal surface, but an image corresponding to when the fan beam 2 is advanced and raised on a horizontal surface. When searching for schools of fish using a scanning sonar using a fan beam like this, the angle of depression φ
Run while keeping constant. By doing this, it is possible to detect a school of fish in front.

However, fish school detection using scanning sonar using fan beams has the following drawbacks.

First, the CRT display only shows the direct distance to the school of fish, not the depth, and the azimuth angle is based on the direction of the transducer, not the boat. is only displayed. In other words, the direction based on the ship;
Since information such as horizontal distance and depth is not formatted, it is difficult to intuitively grasp the location of schools of fish.

Second, since the fan beam is thin to increase resolution in the depression angle direction, schools of small fish instantly pass through the search beam. On the other hand, the exploration images disappear with each transmission, so in order not to miss images of schools of small fish, the operator must constantly stare at the screen, which is extremely tiring work.

Third, even if a school of fish spreads out wider than the thickness of the fan beam in the direction of travel of the vessel, it is difficult to know the spread of the school of fish because only the part crossed by the fan beam is detected by the fan beam. be. In order to find out, we must count the number of consecutive appearances of fish school images.

Fourth, since the fish school image disappears after each exploration, it is not possible to compare the schools of fish that have passed by.

Fifth, in order to track and detect a passing school of fish, you must swing the fan beam in the azimuth direction or change the angle of depression, but the closer you get to the school of fish, the more you have to change the angle. Although this means staying out of the exploration range, it is practically difficult to do this while sailing.

(Object of the Invention) An object of the present invention is to convert the position information of a target detected by a fan beam into information in a form that allows the target position to be easily grasped visually, in order to overcome the drawbacks of the prior art as described above. We provide a display method that allows you to know the change in the target position over time by converting the information and recording the information for every exploration, every fixed number of explorations, or every number of explorations corresponding to the speed of the ship, and by using an image sending method. It's about doing.

(Structure of the Invention) The present invention has the following structure to achieve the above object. That is, in a scanning sonar that uses a fan beam, for each search, the scanning sonar determines the traveling direction of the ship with the position of the ship carrying it as the origin based on three pieces of information: the azimuth angle, the depression angle, and the direct distance of the detected target. The position of the target on the orthogonal coordinates consisting of three axes, the lateral direction and the depth direction, is calculated by a calculation means, and the obtained lateral distance information and depth information are calculated for each exploration or every fixed number of explorations, or for each ship. Each number of explorations corresponding to the speed is recorded in the recording means,
This is a scanning sonar display method for displaying changes over time of the distance information and depth information in the broadside direction recorded by the display means by an image feeding method, and as a first embodiment thereof, an electronic storage circuit is used as the recording means. A scanning sonar display method using a cathode ray tube display as a display means, a second embodiment H a scanning sonar display method using a multi-venn recorder as a recording means and a display means, and a third embodiment a recording means. and a scanning sonar display method using a traveling pen recorder as a display means.

Fourth implementation I! This is a scanning sonar display method in which the depression angle is set to 906 in the second and third embodiments Ii.

The basic idea of the present invention will be explained below.

First, as shown in FIG. 1, the nose (direction toward the center) of the fan beam is set toward the bow at an angle of depression φ. In this case, the position of the fish school 3 captured by the fan beam 2 is expressed by the direct distance, the depression angle φ, and the azimuth angle θ on the plane of the fan beam 2 with respect to the χ axis. This position information is converted into a position representation on orthogonal coordinates consisting of a x-axis, a chi-axis, and a j-axis extending in the depth direction from the position of the ship. Through this transformation, the coordinate values of χ, 2, and / of the fish school 3 become as follows.

That is, Z = l c o sθ ・・・・・・・・・・・・
River・・・・・・・・・(])gu=7sinθ@coSφ
・・・・・・・・・(2) 1=isinθ・sinφ
(3) The present invention attempts to record and display the position of a school of fish using the above coordinates.

For example, real-time image display on a CRT display is performed as shown in FIG. 3' is a school of fish image.

This display is the χ plane (corresponding to the sea surface) of fish school 3.
Projection to and 77 plane (plane corresponding to the cross section seen from the side)
It is said to be a projection display.

This solves the drawback of the conventional scanning sonar display method using a fan beam that it is difficult to visually and intuitively grasp the position of a school of fish.

Next, in the present invention, among the position information on the orthogonal coordinates of The feature of 3) is that the information is recorded for each exploration, for a certain number of explorations, or for each number of explorations corresponding to the ship speed.

Currently, color scanning sonar is widely used, and for this reason, a raster scan method is used for CRT displays. On the other hand, since the position information of fish schools obtained from the scanning sonar itself is in polar coordinate format by spiral scanning, it is necessary to convert the scanning method from spiral scanning to raster scanning. VideoR
andom Access Memory: Below ■-R
AM). In conventional scanning sonar, the image storage in the V-RAM is rewritten every time one search is performed. That is, for each exploration, the previous image memory is erased and a new image is stored.

Therefore, it is conceivable to first utilize this V-RAM as a storage means for positional information in the method of the present invention.

In other words, instead of erasing the previous video memory for each exploration as in the past, the video memory is stored on the V-RAM every exploration, every certain number of explorations, or every number of explorations corresponding to the speed of the ship. −
This is a method of retaining memory by lifting it in the y-force direction. In this way, the image shown in Figure 4 6.6' will appear on the CRT display.
As shown in Figure 2, the detection trajectory of past schools of fish will appear (hereinafter this will be referred to as the image sending method). The storage capacity of the V-RAM may be such that it can store the entire range that can be detected by the fan beam 2, or it can store the received signal within the range surrounded by line 7 in FIG. By shifting the memory, the video signal pushed out from the V-RAM for scanning method conversion is stored in the V-RAM by providing a storage circuit dedicated to subsequent recording. Similarly, a method is adopted in which the data is stored while being shifted and read out on a raster scan CRT display when necessary.

The speed at which the memory is shifted in the V-RAM and the recording-only memory circuit may be shifted for each search as described above, or it may be shifted at the speed of n (n = 2.3.4...・)
The storage element row may be shifted by one row for each exploration, or the n may be shifted not by a constant value but by a value inversely proportional to the ship speed. When shifted every l exploration or every n exploration of a fixed value, if the fish school is captured by the fan beam even if there is no movement between the sonar-equipped boat and the fish school, the fish school image on the CRT display will be inversely proportional. If it is shifted as a variable value in the form of
Since the feed of the image on the RT display is also proportional to the boat speed, the number of consecutive fish school images recorded is proportional to the length of the fish school in the y-axis direction, and the size of the fish school can be determined.

The above is a V-R for scanning method conversion as a recording means.
We have described an example in which an electronic memory circuit dedicated to AM and recording is used, and a raster scan CRT display is used as the display means, but a multi-pen type recorder or belt type can be used as a recording means following the V-RAM for scanning method conversion. It is also possible to use a running pen recorder such as . That is, V-
The images stored in the last row of the RAM are written on recording paper using these pen recorders. The moving speed of the recording paper is V
- Match the shift speed on the RAM. These pen recorders function not only as recording means, but also as display means for the images drawn on the recording paper. Furthermore, if the depression angle is 90'', that is, the fan beam is directed directly downward, V-RAM or raster scan CR
Separately from the T indicator, there is a storage element array that calculates the horizontal distances in the left and right broadside directions of the school of fish and their respective depths from the received fish signal using equations (1) and (3), and temporarily stores the horizontal distance information. It is also possible to cause horizontal distance information and depth information held in this memory element array to be drawn on recording paper using a multi-pen type or belt pen type pen recorder. . In this case, information on the storage element array is updated every l explorations,
The number of probes to be read by the pen recorder may be determined depending on the performance of the pen recorder and other conditions.

This method also achieves the purpose of continuously recording past position information of schools of fish captured by the fan beam.

Figure 5 shows an example in which a V-RAM and a storage circuit similar to the V-RAM are used as a recording means, and a raster scan CRT display is used as a display means to record a detected image of a school of fish. Show the situation.

In the figure, the intersection of the χ axis and the 7th axis is the position of own ship, α is the horizontal distance axis on the starboard side, -o7 to the right is the depth axis of the school of fish on the starboard side, and 0-2 is the horizontal distance on the port side axis, η on the left is the depth axis of the fish school on the port side.

Fl - Fl , Fl' to F4' indicate fish school images. 7
The area above 7 indicates the detection range of the scanning sonar, and normally a V-RAM is provided that can hold the image of this area for scanning method conversion. Therefore,
The portion above 77 may be viewed as a stored image on the V-RAM or as an image on a CRT display. The portion below the 7th frame is a recorded image on a recording means for recording position information pushed out from the V-RAM by image feeding.

The shaded area is the fish school image.

As described above, this recording means may be an electronic storage circuit such as a V-RAM, or may be a multi-pen type or a running pen type pen recorder.

If electronic storage circuitry is used, both the upper and lower 7T images can be displayed together on a raster scan CRT display.

(Example of the invention) Embodiments of the present invention will be described below based on the drawings.

In Figure 6, a raster scan CRT display is used as a display means, and an electronic storage circuit similar to V-RAM is used as a recording means, and the image on the V-RAM and the image on the recording means are shown in Figure 5. FIG. 2 is a block diagram showing a configuration when displaying on a CRT display as shown in FIG.

8 is a transducer, 9 is a transmission/reception switching circuit, 10 is a transmitter, 1
1 is a receiving amplifier, 12 is a distance signal generator, 13 is a scanning circuit, 14 is a scanning signal generator, 15 is a write address circuit, 16 is an AD converter, 17 is a storage circuit including a V-RAM and a recording means (this 18 is a continuous address circuit, 19 is a DA conversion circuit, 20 is a time base generator, 21 is a raster scanning circuit, 22 is a CRT display, and 23 is a depression angle signal generator. Of the above configurations, each configuration other than the write address circuit 15, memory circuit 17, and successive address circuit 18 operates in the same manner as a conventional half-round scanning sonar. The write address circuit 15 receives the azimuth angle signal θ from the scanning signal generator 14 and the depression angle signal generator 23.
The detected fish school is determined from three signals: the depression angle signal φ from the write address circuit 15 itself, and the distance signal Y whose amplitude increases each time the azimuth signal θ exceeds an integral multiple of 180°. The position is calculated according to equations (1) to (3). Next, it is determined where on the CR7 display 22 the position obtained in this way is to be displayed when all the information stored in the memory circuit 17 is displayed two-dimensionally on the CR7 display 22 of raster scan. The address information is converted into an address (position on the X-Y coordinates in FIG. 5) and sent to the storage circuit 17. The fish school signal from the AD converter 16 is recorded at the location indicated by the address information, or is shifted in the minus X direction every few explorations or at a speed proportional to the boat speed. On the other hand, readout is performed by the raster scanning circuit 2 as in the case of normal color scanning sonar.
1 to the CRT display 22, and also sends a signal to the successive address circuit 18.
The display device 2 is sent to the storage circuit 17.

In this way, an image as shown in FIG. 5 is displayed on the CRT display 22.
appear above.

Figure 7 shows a configuration in which the image above 7T in Figure 5 is displayed on a CRT display, and the detection information below 7T is recorded by a traveling pen type recorder such as a belt type. FIG.

In the figure, numbers 8.9.1O111, 13, 14, 15, 1
6, 19, 20, 23, 22, and 23 are the same as in FIG.

17'LLCRT display (7) V-RAM, 1B' is successive address circuit, 24 is memory circuit, 26 is DA converter,
26 is a moving pen type recorder.

The sixth point is that the V-RAM 17' for CRT display is only a memory circuit necessary for displaying the screen on the CR7 display 22.
This is different from the storage circuit 17 shown in the figure. C from V-RAM17'
In addition to the video signal to be displayed on the R7 display 22, the signal from the last column of storage elements for image forwarding is sent to the memory port #I2.
Send to 4.

The read address circuit 18' reads from the V-RAM 17' to CR7.
In addition to sending the address signal on the X-Y coordinates of the video signal to be sent to the display 22 to the V-RAM 17', the last column of the V-RAM (J-- in FIG.
V-R address signal on the Y coordinate (corresponding to the J axis)
Send to AM17'.

The memory port 124 temporarily stores the recording signal from the V-RAM 17', and transmits it via the DA converter 26 as a time series signal in accordance with the travel of the recording pen based on the transmission signal of the traveling pen type recorder 26. It is sent to the traveling pen type recorder 26.

Further, a transmission signal R is sent from the traveling pen type recorder 26 to the transmitter 10 and the write address circuit wa15.

As described above, the image above the 7th block in Figure 5 is CR.
7 display 22, and the image below the 7th display is recorded on the traveling pen type recorder 26.

When the depression angle is set to 90°, there is no image above Jl in FIG. 5, so a CRT display becomes unnecessary. The configuration without this will be fine.

Figure 8 shows a configuration in which the image above ■ in Figure 5 is displayed on a CRT display as in the case of Figure 7, and the image below 7 is recorded by a multi-pen recorder. It is a block diagram.

In the figure, numbers 8 to 16.17', 19 to 23.25 are the 6th
This is the same as in the case of FIG. 18'' is a continuous address circuit, and 26' is a multi-pen recorder.The read address circuit 18' sends an address signal on the X-Y coordinates of the video signal to be sent to the CRT display 22 to the V-RAM 17'. Multi-pen type recorder 26' also records the dress signal.
Send to. The multi-pen recorder 26' reads the V-RAM 17 according to the address signal from the successive address circuit 18''.
It has a built-in circuit that distributes the signal from the final storage element array to each pen.

As described above, the image above ■ in Figure 5 is
The image displayed on the display 22 and below 7] will be recorded on the multi-pen recorder 26'.

When the depression angle is set to 90°, there is no image above the 7th block in Figure 5, so the CR7 display becomes unnecessary.On the other hand, since the multi-pen recorder is capable of high-speed operation, it is not necessary to write the write address signal. The video signal can be directly received from the input address circuit 15, and the video signal can be recorded by directly receiving the output signal of the scanning circuit 13 before AD conversion. Therefore, A in Figure 8
It is sufficient to have a configuration that excludes the D converter 16, V-RAM 17', successive address circuit 18'', DA converter 19, DA converter 25, raster scanning circuit 21, and CRT display 22.The configuration block in this case A diagram is shown in FIG.

(Effects of the Invention) As explained above, in the display method for fish detection using a fan beam of the present invention, the position of the fish school is displayed so that the distance directly above the fish school, the direction from the bow, and the depth can be clearly seen. In addition, the distance and depth of the detected school of fish in the broadside direction are recorded by an image sending method every time a certain number of explorations are made or every exploration according to the speed of the ship, and the continuously recorded data can be observed. Therefore, it has the following excellent effects.

First, compared to conventional semi-circular scanning sonar using fan beams, which can only display the direct distance to the fish school and the direction based on the transducer orientation, it is possible to visually locate the fish school. It has become much easier to understand.

Second, the image of a school of fish detected by the fan beam even once is recorded without disappearing and is recorded using an image forwarding method, so there is no longer a need to keep staring at the display screen to avoid missing a school of fish.

Thirdly, if the fish school spreads out and the vessel is underway,
Since the images of the area illuminated by the fan beam are recorded, the size of the school of fish can be determined by the length of the series of images of the fish school.

Fourth, since images of past fish schools are continuously recorded, it is possible to compare the positions and sizes of schools of fish that have passed by.

Fifth, it is easy to re-track the schools of fish that have passed by.

There are advantages as mentioned above.

[Brief explanation of drawings]

Figure 1 shows how a semi-circular scanning sonar detects a school of fish using a fan beam, and Figure 2 shows a conventional image display on a CRT display of a school of fish detected as shown in Figure 1. 3 is a diagram showing an image display on a CRT display in the method of the present invention, FIG. 4 is a diagram showing an image of a detected school of fish being sent in the opposite direction to the direction of travel of the vessel, and FIG. The figure shows images stored in V-RAM and V-R
FIG. 6 is a diagram showing an image recorded in a storage circuit following AM, and shows the configuration of an embodiment of the present invention using a CRT display as a display means and an electronic storage circuit similar to a V-RAM as a recording means. FIG. 7 is a block diagram showing the configuration of an embodiment of the present invention using a traveling pen type recorder as a recording means, and FIG. 8 is a block diagram showing the configuration of an embodiment of the present invention using a multi-pen type recorder as a recording means. A block diagram showing the configuration of an embodiment,
FIG. 9 is a block diagram showing the configuration of an embodiment of the present invention in which a multi-pen recorder is used as the recording means and the depression angle is 906 degrees. l...Scanning sonar-equipped vessel, 2...Fan beam, 3...Fish school (target) captured by fan beam 2, 3'...Fish school image, 4...The position of vessel l is the origin Coordinate axis in the side direction (χ axis), 5... Coordinate axis in the ship's traveling direction with the origin at the position of ship 1 (, 7 axis), 6
...Video of schools of fish detected continuously, 7...V-RA
A line demarcating the detection range stored in M, 8... Transmitter/receiver, 9... Transmit/receive switching circuit, 10... Transmitter, 11...
・Reception amplifier, 12... Distance signal generator, 13...
Scanning circuit, 14...Scanning signal generator, 15...Write address circuit, 16...AD converter, 17...Storage circuit, ] ]7'-V-RAM, 1818', 18''
...Continuous address circuit, 19...DA converter, 20
. . . Time pace generator, 21 . . Raster scanning circuit, 22 .
...Traveling pen type recorder, 26'...Multi-pen type recorder. 1st ml 211th! ] 1 Day dzu spit - 1 Tea 10 Figure × Figure 6 Day q

Claims (5)

[Claims] (1) In a scanning sonar that uses a fan beam, for each search, the ship's progress from the position of the ship carrying the scanning sonar as its origin is determined based on three pieces of information: azimuth, depression angle, and direct distance of the detected target. A calculation means calculates the target position on orthogonal coordinates consisting of three axes: direction, side direction, and depth direction, and calculates the obtained side direction distance information and depth information for each exploration or for a certain number of explorations. Alternatively, a scanning sonar display method in which a recording means records each number of explorations corresponding to the ship speed, and a display means displays changes over time in the recorded broadside distance information and depth information by an image feeding method. (2) Claim No. 1 uses an electronic storage circuit as a recording means and a cathode ray tube display as a display means.
) How to display scanning sonar as described in section. (3) A scanning sonar display method according to claim 1, which uses a multi-pen recorder as the recording means and the display means. (4) The scanning sonar display method according to claim (1), which uses a traveling pen type recorder as the recording means and the display means. (5) The scanning sonar display method according to claim (3) or (4), wherein the angle of depression of the fan beam is set to 90°.