JPS58100765A - Detector for underwater body - Google Patents

Abstract

PURPOSE:To perform operation under adequate judgement by obtaining the momentary relation between a school of fish and netting and displaying them on the same video screen in three dimensions. CONSTITUTION:Control pulses sent from a control indicator 10 at a specific period are applied to a distance signal transmitter 13 to drive a transmitter 1 for distance measurement, thereby sending out an ultrasonic wave of frequency f1. Receivers 2 and 3 receive a signal sent from a netting depth gauge NF and send outputs to a signal discriminator 5 and a time difference detector 6. Outputs of the time difference detector 6 and a depth detector 7 are supplied to a signal arithmetic device 8 to calculate the horizontal distance and horizontal azimuth of the netting. A signal synthesizer 9 outputs sonar information and information on the netting, which are displayed on the cathode-ray tube of the control indicator 10.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an underwater object detection device such as a sonar.

In purse seine fishing, for example, the net is operated by a regular boat. In the case of retrieval, one end of the net N, which is equipped with the fishing net, the float (2) and the hook (W) shown in Figures 1 and 2, is tied to the buoy B, and the boat S surrounds the school of fish F as shown by the arrow. The boat sails while lowering the net N.

This method of fishing depends on the structure of the net used, and is called the hanging method.A rope passed through a ring at the bottom of the net is pulled up in the direction of arrow D2, making the net into a bag. A school of fish is scooped out by tightening a hanging bag used for storage around the mouth.

However, if the net is hoisted up before it has settled sufficiently, it will not be able to enclose the entire school of fish, and only the top of the school of fish will be scooped up. Also, if the net takes too long to settle, the school of fish will pass through the bottom of the net while the net is settling and be dispersed.

As a countermeasure, a net depth meter NF is installed below the net to detect water pressure, convert it to the depth of the net, and send this information to the vessel as a sonic or ultrasonic signal, and the vessel receives the signal. I try to know the depth of the net.

By the way, the scanning sonar mounted on a ship and used for detecting schools of fish displays the underwater swimming status, such as the depth, distance, and direction of schools of fish, on the screen of a cathode ray tube (generally, P
It is a well-known fact that the PI is a PI).

However, since the information sent from the net depth meter NF mentioned above is simply the depth of the net, the relative relationship with the ever-changing fish school is unknown. Therefore, when targeting fast-moving fish schools, It is difficult to operate casting nets and hauling nets based on accurate judgment, and currently people rely on their intuition.

In order to eliminate this drawback, the present invention attempts to correlate the school of fish and the position of the net from time to time and display them three-dimensionally on the same image plane.

With reference to the figure, from the time difference depth d, ma and d~ of equation (1) as the quantities corresponding to d, -d, with reference to Figure 6, d
The horizontal distance component d)III of N is (1■=4π・−・−・−・−・(8) Next, referring to Figures 6 and 7, project the position of the net depth meter NF onto the water surface. The point A is the angle 61 of the OA connecting this point and the origin 0 with respect to the Y-axis direction OB (this direction actually indicates the ship's traveling direction).
Based on the data obtained by the ship's transducers T and T, and the depth data from the net depth meter NF, we can calculate the horizontal distance dl11 of the net relative to the own ship and the horizontal direction a, converted in the horizontal direction. can be calculated, and the depth of the net is the detection value d and ma of the net depth meter NF, so using these values, we can calculate the relative position between the net and the school of fish. It can be seen that it can be clearly captured.

Now, based on the above basic analysis, we can apply this to the device and describe how to display it on the picture screen of the cathode ray tube. Separate the net and attach the net depth gauges NF1 and NF2 (However, these have the function of receiving the signal from the vessel's NS mentioned above and sending out a response signal). When the NFII and NF'21 (but only for depth detection) are installed, the cathode ray tube displays an image as shown in Fig. 9.

In other words, horizontal distances dmm* and d between the fish schools FSNF1 and NF2 in the plane of a circle centered on the point expanded in the area of the upper row 1.
, the image showing intuition (see - mark) and the images of NFtl and NF21 (see ○ mark) are shown.

The lower area 2 shows the vertical exploration line. In order to search for a specific direction (in the figure, the direction of the school of fish), the ship's detection transducer is set at an angle of depression of 0, and the center of the ultrasonic beam is set at 0.
In this case, the net depths dM1* and d,
The moths are indicated by the net depth gauges NFt and NF2 at the positions indicated by the marks, respectively.

Then, the net depth meter NFII and NF21, which had sand thrown at the upper end of the net, were used.
Fi is shown near the water surface at a position such as O.

It is clear that a cross-sectional view of the net can be obtained by attaching multiple net depth gauges in the direction of the height of the net.In this case, it is possible to obtain a cross-sectional view of the net. Since you can sense when the fish are doing something, you can take action to retrieve the net before it becomes a problem, so you can use this method if necessary.

Next, an example will be described. Figure 10 is a block diagram of the embodiment, consisting of the ship's individual and the network side B. On the ship's side A, L is composed of a transmitter 1 and a receiver 2 for distance measurement; , L is the receiver 3 for distance measurement;
and L are installed at a constant interval d.

4 is a P wave detector, 5 is a Fi signal discriminator, 6 is a time difference detector, 7
is a depth detector, 8 is a signal calculator, 9 is a signal synthesizer, 1G
is a control indicator, 11 is a transceiver, 12 is a sonar transducer, and 13 is a distance signal transmitter.O Next, in the net depth meter of net 11B, 14 is a distance measurement receiver, ! 5 is a response transceiver, 16 is a distance/depth signal transmitter, 17 is a Fi depth signal transmitter, and 18 is a depth signal generation circuit. The operation is as follows.

Control pulses generated from the control indicator 10 at regular intervals are applied to the distance signal transmitter 13, and when the distance measurement transmitter 1 is driven, an ultrasonic wave with a frequency f is transmitted. 14, the response transceiver 15 is activated and transmits a response signal of frequency f from the wave transmitter 16. On the other hand, the depth signal generation circuit 18 and the exploration signal transmitter 17 generate signals with frequencies proportional to the depth, and transmit signals with frequencies f2 to f from the transmitting wave -1G.

Receivers 2 and 3 receive the frequency f sent from the net depth meter,
and f, ~f Hatake signals, among which the output of the receiver 2 is discriminated between frequencies f and f, ~f4 by a signal discrimination circuit 5, and only the signal of frequency ft is sent to a time difference detector 6. ,
At the same time, signals of frequencies f and -f are sent to the depth detector 7.

Among the outputs of the wave receiver 3, the frequencies f4 to f4 are removed by the r wave generator 4, and the signal of the frequency a6 is taken out and sent to the time difference detector 6.

Since the signals of frequency f arriving at the receivers 2 and 3 are created by propagating different distances, their arrival times are different, and the time difference is detected by the time difference detector 6.

Also, the frequency f sent from the signal discriminator 5 to the depth detector 7
, ~f4 is a signal whose frequency is proportional to the depth, so the depth is detected by the depth detector 7. Next, the outputs of the time difference detector 6 and the depth detector 7 are applied to the signal calculator 8. Then, the horizontal distance dIM of the network, the horizontal direction -■, etc. are calculated, and the output thereof is applied to the signal synthesizer 9.

This signal synthesizer 9 is driven by a transmitter/receiver 11 activated in response to a control pulse from the control indicator 100, and is sent out from a sonar transceiver 12 at a frequency f, and receives an ultrasonic wave reflected from a school of fish, etc. is being applied, so the sonar information and information regarding the network appear in the output of the signal synthesizer 9, and these are sent to the output tube of the control indicator 10.
The example shown above is clearly displayed.

When displaying, schools of fish and net depth gauges are shown in different colors, and if multiple net depths are used, they are shown in different colors. do it.

Furthermore, although the sonar transmission pulse and the transmission pulse for obtaining network information are synchronized in the embodiment, it goes without saying that they do not necessarily need to be synchronized.

As is clear from the above explanation, by displaying sonar information and net information on the screen (aCt), the relative relationship between the fish school and the net is clearly shown, and the net information relative to your own boat is clearly shown. Since the horizontal distance and depth of the net can be seen at a glance, it can be used extremely effectively for silk fishing operations.

[Brief explanation of the drawing]

1.2.3.4.5.6.7.8 is a diagram for explaining the basic matters of the present invention. FIG. 9 is a display example according to the present invention. FIG. 10 is a pull diagram of the embodiment. l... Transmitter, 2... Receiver, 3... Distance receiver, 5... Signal discriminator, 6... Time difference detector, 7...
...Depth detector, 8...Signal calculator, 9...Signal synthesizer, 1o...Control indicator, 11...Transmitter/receiver, 1
2...Sonar transducer/receiver, 13...Distance signal transmitter, 14...Distance measurement receiver 1 15...Response transceiver, 16...Distance and depth signal transmitter device, 17...depth signal transmitter, 18...depth signal generation circuit, patent applicant Kaiyo Denki Co., Ltd.
31 Shiko (ro) -■ Tsuriimaguchi No. 5 Zucha 6 Old JII71iiiI:! 7
¥81 1 Figure 9 Figure 10 Procedural amendment (voluntary) January 73, 1980 Commissioner of the Patent Office Shima 1) Haruki fl;-rypl
fz; Indication of Nana Kepay 11 case Patent application 2 filed on December 11, 1981, title of invention 采! 3.Relationship with the case of the person making the amendment Patent applicant address: 6if6, Akane, Tokyo 1-195, Contents of the amendment (4) A page was missing, so a supplementary sheet has been added. do. Prior to describing embodiments of the present invention, basic matters regarding the present invention will be described. A transducer T, which serves as both a transmitter and receiver for distance measurement, and a receiver are installed at a known interval 4 on the bottom (or under the side) of the ship NS (see Figure 3). do. When the transducer T1 sends out a signal for detecting the distance to the net depth meter NF at time t6, it receives the net depth meter NPH signal a and immediately sends out a response signal. The transducers T and - of the ship NS are at time t, respectively. It is assumed that response signals arriving after propagating distances d and d are also received at and t, and the time differences between transmission times t and tl are respectively to and t. If the straight line distance between the vessel NS and the net depth meter NF is dM・(see Figure 4), then in practical terms d, >> d, , dt >>
> c, so if the underwater sound speed is q, then t・嘗+t＠−

Claims (1)

[Claims] The system consists of a sonar equipped on the vessel for detecting underwater objects, and a net R pointer attached to the fishing net operated by the vessel.
The net depth meter detects the depth of the net, converts the information into frequency, etc., and sends it to the ship, and sends a response signal to the ship in response to the ranging signal sent from the transmitter installed on the ship. The ship receives signals from the net depth meter that are received by two receivers installed at a certain distance,
A means for detecting the depth from among the signals, a means for detecting the arrival time difference of the response signal from the net depth meter that arrives at both of the two receivers, and a means for processing the data of the depth and time difference. The present invention is characterized by comprising means for calculating the horizontal distance, horizontal direction, etc. of the net with respect to own ship, means for synthesizing the calculation results with detection information by sonar, and means for displaying the synthesized information. Underwater object detection device.