NL2027867B1 - On-site quick calibration system for fish finder and method thereof - Google Patents

On-site quick calibration system for fish finder and method thereof Download PDF

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Publication number
NL2027867B1
NL2027867B1 NL2027867A NL2027867A NL2027867B1 NL 2027867 B1 NL2027867 B1 NL 2027867B1 NL 2027867 A NL2027867 A NL 2027867A NL 2027867 A NL2027867 A NL 2027867A NL 2027867 B1 NL2027867 B1 NL 2027867B1
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standard sphere
fish finder
acoustic
underwater
sphere
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NL2027867A
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Dutch (nl)
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NL2027867A (en
Inventor
Wang Xuefang
Tong Jianfeng
Zhang Jin
Tian Siquan
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Univ Shanghai Ocean
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    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01S—RADIO DIRECTION-FINDING; RADIO NAVIGATION; DETERMINING DISTANCE OR VELOCITY BY USE OF RADIO WAVES; LOCATING OR PRESENCE-DETECTING BY USE OF THE REFLECTION OR RERADIATION OF RADIO WAVES; ANALOGOUS ARRANGEMENTS USING OTHER WAVES
    • G01S15/00—Systems using the reflection or reradiation of acoustic waves, e.g. sonar systems
    • G01S15/88—Sonar systems specially adapted for specific applications
    • G01S15/96—Sonar systems specially adapted for specific applications for locating fish
    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01S—RADIO DIRECTION-FINDING; RADIO NAVIGATION; DETERMINING DISTANCE OR VELOCITY BY USE OF RADIO WAVES; LOCATING OR PRESENCE-DETECTING BY USE OF THE REFLECTION OR RERADIATION OF RADIO WAVES; ANALOGOUS ARRANGEMENTS USING OTHER WAVES
    • G01S7/00—Details of systems according to groups G01S13/00, G01S15/00, G01S17/00
    • G01S7/52—Details of systems according to groups G01S13/00, G01S15/00, G01S17/00 of systems according to group G01S15/00
    • G01S7/52004—Means for monitoring or calibrating

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  • Engineering & Computer Science (AREA)
  • Radar, Positioning & Navigation (AREA)
  • Remote Sensing (AREA)
  • Physics & Mathematics (AREA)
  • Computer Networks & Wireless Communication (AREA)
  • General Physics & Mathematics (AREA)
  • Acoustics & Sound (AREA)
  • Measurement Of Velocity Or Position Using Acoustic Or Ultrasonic Waves (AREA)

Abstract

The present disclosure discloses an on-site quick calibration system for a fish finder and a method thereof, which solve the defects of time-consuming of underwater positioning of a standard sphere, low calibration accuracy, high cost and beam-limited condition during the marine living resources acoustic survey using eXisting ultrasonic fish finder. The gist of the technical scheme comprises a fish finder transducer, a standard sphere, two acoustic beacons respectively fixedly connected above and below the standard sphere, three hydrophones, a central console, and three take-up and pay-off components. According to the on-site quick calibration system for a fish finder and the method thereof, the underwater positioning and automatic position control of the standard sphere for calibration of a fish finder can be quickly realized, and the efficiency and the accuracy of on-site acoustic parameter calibration of the fish finder can be improved.

Description

ON-SITE QUICK CALIBRATION SYSTEM FOR FISH FINDER AND
METHOD THEREOF
TECHNICAL FIELD
The present disclosure relates to the field of marine fishery resources survey, in particular to an on-site quick calibration system for a fish finder and a method thereof.
BACKGROUND
As the main instrument for acoustic assessment of fishery resources, an ultrasonic fish finder has a principle based on the corresponding relationship between the intensity of echo of a detection target and the size and/or number of targets. Simply speaking, the larger the target, the stronger the echo, and the more the number, the stronger the echo.
When using a fish finder to quantitatively assess fishery resources, the fish finder system must be calibrated, including the echo intensity and the underwater three-dimensional position of the target. The existing calibration method for a fish finder system is to use a standard sphere with known echo intensity at the operating frequency of a fish finder as a reference for system calibration.
Because of the narrow beam of a fish finder and the small diameter of a standard sphere, it is difficult to find the echo of the standard sphere through the echo display screen of the fish finder. For single beam system, it is impossible to know the deviation direction of the standard sphere with respect to the acoustic axis. Even if the standard sphere echo is found on the fish finder screen, it is impossible to know how to control the standard sphere to make it close to the center of the acoustic axis in the next step.
Because it is impossible to know the specific position of the standard sphere on the acoustic axis, the calibration accuracy is low. Under the influence of the difficulty of positioning the standard sphere, the existing calibration technology of a fish finder is time-consuming and labor-consuming, the time cost of a general survey ship is high, and the sea state window suitable for calibration time is uncertain, which increases the cost of survey at sea.
SUMMARY
The object of the present disclosure is to provide an on-site quick calibration system for a fish finder and a method thereof, the underwater positioning and automatic position control of the standard sphere for calibration of the fish finder can be quickly realized, and the efficiency and the accuracy of on-site acoustic parameter calibration of the fish finder are improved.
The above technical object of the present disclosure is achieved by the following technical scheme.
The present disclosure relates to an on-site quick calibration system for a fish finder, comprising a fish finder transducer, further comprising: a standard sphere, which is installed right below the fish finder transducer to be used as a reference for calibration; two acoustic beacons, which are fixedly connected above and below the standard sphere, respectively, send beacon underwater acoustic signals, and have built-in depth sensors for outputting beacon depth signals; three hydrophones, which receive and convert beacon underwater acoustic signals sent by acoustic beacons; a central console, which is coupled to the hydrophone, receives the converted beacon underwater acoustic signal and the beacon depth signal, calculates and obtains the underwater three-dimensional position of the standard sphere, and outputs a control signal; three take-up and pay-off components, each of which comprises a winding reel, a suspension wire, a winch and a controller, wherein the suspension wire is fixedly connected with the acoustic beacon above the standard sphere; the controller is coupled to the central console, responds to the control signal to control the winch to retract and release the suspension wire, and adjusts and controls the position of the standard sphere.
Preferably, two acoustic beacons are equidistant from the standard sphere.
Preferably, a weighting hammer is fixedly installed on the acoustic beacon located below the standard sphere.
Preferably, a Hall sensor for detecting the length of the take-up and pay-off wire is installed on the winding reel, and the controller is coupled to the Hall sensor.
Preferably, the winch is in wireless/wired connection with the controller.
The present disclosure relates to an on-site quick calibration method for a fish finder, comprising the steps of: fixing the standard sphere by the suspension wires of the three take-up and pay-off components, and controlling the take-up and pay-off of the suspension wires by the winch to adjust the underwater position of the standard sphere; acquiring the underwater three-dimensional position of the standard sphere according to the underwater position information of acoustic beacons installed at equal distances above and below the standard sphere; calibrating the fish finder transducer according to the underwater three-dimensional position and the echo information of the standard sphere.
Preferably, acquiring the underwater three-dimensional position of the standard sphere specifically comprises: calculating and obtaining the horizontal positions of the two acoustic beacons,
IO respectively, according to the arrival time difference when the beacon underwater acoustic signals sent by the acoustic beacons above and below the standard sphere reach the three hydrophones, and obtaining the vertical positions of the acoustic beacons according to the beacon depth signals detected and acquired by the depth sensors of the acoustic beacons; determining the underwater positioning area of the standard sphere according to the position relationship between the standard sphere and two acoustic beacons, and confirming the underwater three-dimensional position of the standard sphere in conjunction with the echo information of the standard sphere obtained by the fish finder.
To sum up, the present disclosure has the following beneficial effects.
Through two acoustic beacons provided above and below the standard sphere and combined with three hydrophones, the positioning can be accurately realized, and the efficiency of three-dimensional positioning of the underwater standard sphere can be improved; without being limited by a split beam or a single beam system, the application is more convenient and universal with high efficiency and high precision, so that survey at sea is lower in cost and controllable.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a schematic structural diagram of the system.
In the figure: 1. Hull; 2. Take-up and pay-off component; 3. Hydrophone; 4.
Acoustic beacon; 5. Standard sphere; 6. Weighting hammer.
DETAILED DESCRIPTION
The present disclosure will be further described in detail with reference to the accompanying drawings.
The transducer of fish finder is installed under the bottom of the ship. In the field survey, the sensitivity difference, interface plug and pull, and environmental difference between ultrasonic transducers will cause errors in the fish finder system. In addition, the position of the detection target in the transducer beam is different. Because of the directivity of the acoustic beam and the attenuation of the underwater propagation of the acoustic wave, it is necessary to locate the target accurately and therefore compensate for the backscattering energy. Therefore, when using a fish finder to quantitatively assess fishery resources, the fish finder system must be calibrated, including the echo intensity and the underwater three-dimensional position of the target. At present, the standard sphere 1s manually controlled just below the transducer by three hand-pay-off winding reels on the ship rail, and the fish finder is calibrated by the echo reflected by the standard sphere.
The effective beam angle of a fish finder is relatively small, and the scientific fish finder is generally 8°, so itis difficult to control the position of the standard sphere within the beam. The survey environment at sea is changeable, and sometimes it is difficult to find the echo of the standard sphere from the fish finder screen due to being affected by ocean currents and waves, so that it is time-consuming and labor-consuming to calibrate.
For single beam system, it is impossible to know the deviation direction of the standard sphere with respect to the acoustic axis. Even if the standard sphere echo is found on the fish finder screen, it is impossible to know how to control the standard sphere to make it close to the center of the acoustic axis in the next step. Because it is impossible to know the specific position of the standard sphere on the acoustic axis, the calibration accuracy is low. Under the influence of the difficulty of positioning the standard sphere, the existing calibration technology of a fish finder is time-consuming and labor-consuming, the time cost of a general survey ship is high, and the sea state window suitable for calibration time is uncertain, which increases the cost of survey at sea. Whereas, the existing split beam fish finder uses the arrival time difference when echo reaches each quadrant of the transducer to calculate the position deviation of the standard sphere with respect to the acoustic axis center of the transducer. Because the size of the fish finder transducer is small and the arrival time difference is small, the calculated position deviation accuracy is low.
According to one or more embodiments, an on-site quick calibration system for a fish finder is disclosed, comprising a hull for offshore operation. As shown in FIG. 1, the system further comprises a fish finder transducer, a standard sphere, two acoustic beacons, a hydrophone, a take-up and pay-off component and a central console.
The fish finder transducer is installed under the hull for detection. The standard 5 sphere is installed right below the fish finder transducer to be used as a reference to calibrate the fish finder transducer.
Three take-up and pay-off components are provided, each of which comprises a winding reel, a suspension wire, a winch and a controller. The suspension wire is coiled by the winding reel, and the suspension wire is retracted and released by the winch. The
IO winch is controlled by the controller. The standard sphere is fixedly connected underwater by the suspension wires of three take-up and pay-off components. A Hall sensor for detecting the length of the take-up and pay-off wire is installed on the winding reel. The Hall sensor acquires the length information of the take-up and pay-off wire according to the radius of the winding reel. The number of the Hall sensors is encrypted equidistantly by the rotating wheel of the winding reel to improve the control accuracy of the wire length. The Hall sensor outputs the detected length information of the take- up and pay-off wire to the controller.
Two acoustic beacons are respectively provided above and below the standard sphere at equal distance from the standard sphere, and are provided on the upper and lower sides of the standard sphere. The acoustic beacons above the standard sphere are fixedly connected with the suspension wires of the take-up and pay-off components, and the acoustic beacons below the standard sphere are fixedly provided with weighting hammers, thus increasing the overall weight and reducing the influence of water flow.
The acoustic beacon sends a beacon underwater acoustic signal correspondingly, and a depth sensor is built in the acoustic beacon to detect the depth information of the acoustic beacon in water in real time and output the beacon depth signal.
Three hydrophones are provided, which are used to receive beacon underwater acoustic signals sent by two acoustic beacons, and carry out acoustic-electrical conversion on the received beacon underwater acoustic signals and transmit them to the central console.
The central console can calculate and obtain the horizontal positions of the two acoustic beacons according to the arrival time difference when the beacon underwater acoustic signals sent by the two acoustic beacons reach each hydrophone. Then,
according to the position between the two acoustic beacons and the standard sphere, combined with the water flow elements, the positioning range of the standard sphere can be narrowed, and the standard sphere can be quickly found. According to the beacon depth signals detected by the depth sensors built in the two acoustic beacons received by the central console, the vertical position of the standard sphere in water can be obtained, and then the underwater three-dimensional position area of the standard sphere can be obtained. According to the echo information of the standard sphere, the underwater positioning is carried out accurately. The echo information includes echo intensity, echo depth and phase information for the split beam system.
The central console is wirelessly connected with the controller of each take-up and pay-off component through wireless network or is in wired connection with the controller. The central console outputs the generated control signal to the controller, and the length information output by the Hall sensor received by the controller is transmitted to the central console. The controller communicates with the central console bidirectionally, so that the controller can control the winch in response to the control signal.
The central console also predicts the influence of ocean current on the standard sphere according to the underwater movement of the standard sphere, and predicts and controls the position of the standard sphere according to the real-time position of the standard sphere, the spatial layout of the winch and the length relationship of the take- up and pay-off wire.
Three hydrophones combined with two acoustic beacons are used to three- dimensionally positioning the standard sphere underwater, which can improve the positioning accuracy without being limited by a split beam or single beam system.
According to one or more embodiments, the present disclosure discloses an on-site quick calibration method for a fish finder, comprising the steps of: fixing the standard sphere by the suspension wires of the three take-up and pay-off components, and controlling the take-up and pay-off of the suspension wires by the winch to adjust the underwater position of the standard sphere; acquiring the underwater three-dimensional position of the standard sphere according to the underwater position information of acoustic beacons installed at equal distances above and below the standard sphere; calibrating the fish finder transducer according to the underwater three-dimensional position and the echo information of the standard sphere.
Specifically, the specific steps of acquiring the underwater three-dimensional position of the standard sphere comprise: calculating and obtaining the horizontal positions of the two acoustic beacons, respectively, according to the arrival time difference when the beacon underwater acoustic signals sent by the acoustic beacons above and below the standard sphere reach the three hydrophones, and obtaining the vertical positions of the acoustic beacons according to the beacon depth signals detected and acquired by the depth sensors of the acoustic beacons; obtaining the underwater three-dimensional position area of the standard sphere according to the position relationship between the standard sphere and two acoustic beacons, and accurately positioning the standard sphere underwater in conjunction with the echo information of the standard sphere.
This specific embodiment is only an explanation of the present disclosure, rather than a limitation on the present disclosure. After reading this specification, those skilled in the art can modify this embodiment without creative contribution as needed, which 1s protected by the patent law as long as it is within the scope of the claims of the present disclosure.

Claims (7)

Conclusies l. Snel kalibratiesysteem voor een visvinder op locatie, waarbij het kalibratiesysteem een visvinderomvormer omvat, waarbij het kalibratiesysteem verder het volgende omvat: een standaardbol, die precies onder de visvinderomzetter geinstalleerd is die als een referentie voor kalibratie gebruikt moet worden; twee akoestische bakens, die vast respectievelijk boven en onder de standaardbol bevestigd zijn, die akoestische onderwaterbakensignalen verzenden, en ingebouwde dieptesensoren hebben voor het uitgeven van bakendieptesignalen; drie hydrofoons, die akoestische onderwaterbakensignalen die door akoestische bakens verzonden zijn, ontvangen en omzetten; een centraal bedieningspaneel, dat aan de hydrofoon gekoppeld is, dat het omgezette akoestische onderwaterbakensignaal en het bakendieptesignaal ontvangt, de driedimensionale onderwaterpositie van de standaardbol berekent en verkrijgt, en een regelsignaal uitgeeft; drie oprol- en afrolcomponenten, die elk een windspoel, een ophangdraad, een lier en een regelaar omvatten; waarbij de ophangdraad vast bevestigd is aan het akoestische baken boven de standaardbol, waarbij de regelaar gekoppeld is aan het centrale bedieningspaneel, op het regelsignaal reageert om de lier te regelen om de ophangdraad terug te trekken en vrij te geven, en de positie van de standaardbol aanpast en regelt.Conclusions l. Rapid on-site fish finder calibration system, the calibration system comprising a fish finder transducer, the calibration system further comprising: a standard sphere installed just below the fish finder transducer to be used as a reference for calibration; two acoustic beacons, fixed respectively above and below the standard sphere, transmitting acoustic underwater beacon signals, and having built-in depth sensors for outputting beacon depth signals; three hydrophones, which receive and convert underwater acoustic beacon signals transmitted by acoustic beacons; a central control panel, coupled to the hydrophone, which receives the converted underwater beacon acoustic signal and the beacon depth signal, calculates and obtains the three-dimensional underwater position of the standard sphere, and outputs a control signal; three winding and unwinding components, each of which includes a reel, a suspension wire, a winch and a regulator; wherein the suspension wire is fixedly attached to the acoustic beacon above the standard sphere, the controller coupled to the central control panel, responding to the control signal to control the winch to retract and release the suspension wire, and the position of the standard sphere adjust and regulate. 2. Snel kalibratiesysteem voor een visvinder op locatie volgens conclusie 1, waarbij twee akoestische bakens zich op gelijke afstand van de standaardbol bevinden.The rapid on-site fish finder calibration system of claim 1, wherein two acoustic beacons are equidistant from the standard sphere. 3. Snel kalibratiesysteem voor een visvinder op locatie volgens conclusie 2, waarbij een verzwaarde hamer vast geïnstalleerd is op het akoestische baken dat zich onder de standaardbol bevindt.A rapid on-site fish finder calibration system according to claim 2, wherein a weighted hammer is fixedly installed on the acoustic beacon located below the standard sphere. 4. Snel kalibratiesysteem voor een visvinder op locatie volgens conclusie 1, waarbij een serie Hall-sensoren voor het detecteren van de lengte van de oprol- en afroldraad geïnstalleerd is op de windspoel, en de regelaar gekoppeld is aan de Hall-sensoren.The on-site rapid calibration system for a fish finder according to claim 1, wherein a series of Hall sensors for detecting the length of the reel and reel wire is installed on the wind coil, and the controller is coupled to the Hall sensors. 5. Snel kalibratiesysteem voor een visvinder op locatie volgens conclusie 4, waarbij de lier in draadloze/bedrade verbinding met de regelaar is.The rapid on-site fish finder calibration system of claim 4, wherein the winch is in wireless/wired communication with the controller. 6. Snelle kalibratiewerkwijze voor een visvinder op locatie , waarbij de werkwijze de volgende stappen omvat: het vastmaken van de standaardbol middels de ophangdraden van de drie oprol- en afrolcomponenten, en het regelen van de oprol en afrol van de ophangdraden door de lier om de onderwaterpositie van de standaardbol aan te passen; het verwerven van de driedimensionale onderwaterpositie van de standaardbol volgens de onderwaterpositie-informatie van akoestische bakens die op gelijk afstanden boven en onder de standaardbol geïnstalleerd zijn; het kalibreren van de visvinderomzetter volgens de driedimensionale onderwaterpositie en de echo-informatie van de standaardbol.6. Rapid calibration method for an on-site fish finder, the method comprising the steps of: fixing the standard sphere by the suspension wires of the three coiling and unwinding components, and controlling the winding and unwinding of the suspension wires by the winch to make the adjust the underwater position of the default sphere; acquiring the three-dimensional underwater position of the standard sphere according to the underwater position information of acoustic beacons installed at equal distances above and below the standard sphere; calibrating the fish finder transducer according to the three-dimensional underwater position and the echo information from the standard sphere. 7. Snelle kalibratiewerkwijze voor een visvinder op locatie volgens conclusie 6, waarbij het verwerven van de driedimensionale onderwaterpositie van de standaardbol specifiek het volgende omvat: het respectievelijk berekenen en verkrijgen van de horizontale posities van de twee akoestische bakens, volgens het verschil in aankomsttijd wanneer de akoestische onderwaterbakensignalen die door de akoestische bakens boven en onder de standaardbol verzonden worden de drie hydrofoons bereiken, en het verkrijgen van de verticale posities van de akoestische bakens volgens de bakendieptesignalen die gedetecteerd en verworven worden door de dieptesensoren van de akoestische bakens; het bepalen van het onderwaterpositioneringsgebied van de standaardbol volgens de positierelatie tussen de standaardbol en twee akoestische bakens, en het bevestigen van de driedimensionale onderwaterpositie van de standaardbol in samenhang met de echo- informatie van de standaardbol die verkregen wordt door de visvinder.The rapid calibration method for an on-site fish finder according to claim 6, wherein acquiring the three-dimensional underwater position of the standard sphere specifically comprises: calculating and obtaining the horizontal positions of the two acoustic beacons, respectively, according to the difference in arrival time when the underwater acoustic beacon signals transmitted by the acoustic beacons above and below the standard sphere reaching the three hydrophones, and obtaining the vertical positions of the acoustic beacons according to the beacon depth signals detected and acquired by the depth sensors of the acoustic beacons; determining the underwater positioning area of the standard sphere according to the position relationship between the standard sphere and two acoustic beacons; and confirming the three-dimensional underwater position of the standard sphere in conjunction with the echo information from the standard sphere acquired by the fish finder.
NL2027867A 2020-08-27 2021-03-30 On-site quick calibration system for fish finder and method thereof NL2027867B1 (en)

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CN115047468B (en) * 2022-04-28 2023-03-28 中国水产科学研究院南海水产研究所 Fish shoal amount monitoring system of large-scale deep and open sea aquaculture fishing ground

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JPH0954151A (en) * 1995-08-15 1997-02-25 Kaijo Corp Apparatus for positioning calibration ball of fish finder
JP2916908B2 (en) * 1997-04-21 1999-07-05 広島県 Simple aerial imaging device using a moored balloon
US9223008B1 (en) * 2010-03-02 2015-12-29 Advanced Optical Systems Inc. Load tracking and stabilization
CN203204178U (en) * 2013-04-22 2013-09-18 中国水产科学研究院东海水产研究所 Simple standard object correcting device for acoustic detector
CN103965926B (en) * 2014-05-13 2015-12-30 攀钢集团西昌钢钒有限公司 Compactor on-line correction device and method
US20160069988A1 (en) * 2014-09-05 2016-03-10 Woods Hole Oceanographic Institution Platform-Independent Sonar Calibration Enabling System
FR3086397A1 (en) * 2018-09-25 2020-03-27 Notilo Plus METHOD AND DEVICE FOR LOCATING AN ACOUSTIC TRANSMITTER
CN111537983A (en) * 2020-05-29 2020-08-14 中国极地研究中心 Fish finder calibration device

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