WO1996015663A1 - Feed waste detector - Google Patents

Feed waste detector Download PDF

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Publication number
WO1996015663A1
WO1996015663A1 PCT/NO1995/000209 NO9500209W WO9615663A1 WO 1996015663 A1 WO1996015663 A1 WO 1996015663A1 NO 9500209 W NO9500209 W NO 9500209W WO 9615663 A1 WO9615663 A1 WO 9615663A1
Authority
WO
WIPO (PCT)
Prior art keywords
sound
hydrophone
fodder
objects
loss
Prior art date
Application number
PCT/NO1995/000209
Other languages
French (fr)
Inventor
Ole Molaug
Original Assignee
Akva A/S
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Family has litigation
First worldwide family litigation filed litigation Critical https://patents.darts-ip.com/?family=19897619&utm_source=google_patent&utm_medium=platform_link&utm_campaign=public_patent_search&patent=WO1996015663(A1) "Global patent litigation dataset” by Darts-ip is licensed under a Creative Commons Attribution 4.0 International License.
Application filed by Akva A/S filed Critical Akva A/S
Priority to US08/836,728 priority Critical patent/US5978315A/en
Priority to AU39391/95A priority patent/AU3939195A/en
Priority to CA002204907A priority patent/CA2204907C/en
Priority to JP8516372A priority patent/JPH10512743A/en
Priority to EP95937228A priority patent/EP0802723B1/en
Publication of WO1996015663A1 publication Critical patent/WO1996015663A1/en

Links

Classifications

    • A—HUMAN NECESSITIES
    • A01—AGRICULTURE; FORESTRY; ANIMAL HUSBANDRY; HUNTING; TRAPPING; FISHING
    • A01K—ANIMAL HUSBANDRY; AVICULTURE; APICULTURE; PISCICULTURE; FISHING; REARING OR BREEDING ANIMALS, NOT OTHERWISE PROVIDED FOR; NEW BREEDS OF ANIMALS
    • A01K61/00—Culture of aquatic animals
    • A01K61/60—Floating cultivation devices, e.g. rafts or floating fish-farms
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
    • Y02A—TECHNOLOGIES FOR ADAPTATION TO CLIMATE CHANGE
    • Y02A40/00—Adaptation technologies in agriculture, forestry, livestock or agroalimentary production
    • Y02A40/80—Adaptation technologies in agriculture, forestry, livestock or agroalimentary production in fisheries management
    • Y02A40/81—Aquaculture, e.g. of fish

Definitions

  • the invention relates to a method and a device for detecting fodder loss and waste in connection with the breeding of fish.
  • Fodder loss and waste represent great losses of value in the breeding of fish and, moreover, fodder loss and waste result in pollution. It is important to the breeder to utilize the growth potential of the fish as good as possible, and to achieve this, the allott ent of fodder must be close to maximum. External environmental changes, e.g. the seeping in of colder water, may rapidly reduce the appetite of the fish, thus causing excess feeding, resulting in fodder loss and waste, especially when automatic feeding machines are used. It is known to control the feeding in relation to water temperature and other factors, but these measures have not been sufficient to avoid waste and loss of fodder. One has tried to measure the appetite of the fish as a function of its activity and reaction to feeding, but this approach has not given a satisfactory result either.
  • a need for a device capable of detecting fodder loss and waste directly in order to reduce the supply of fodder has existed since a long time ago.
  • Several devices for detecting waste and loss of fodder have been tried out.
  • a known detecting device utilizes an echo sounder principle combined with a computer analyzing a relatively complex echo sounder image, but this device has not spread, firstly because it is too expensive and secondly because it does not give a reliable detection.
  • the pollution problem was reduced upon the arrival of devices collecting fodder not eaten.
  • Such devices for collecting fodder comprise a bag which is attached beneath the "fence" enclosung the fish. Also, it is known to dispose risers with gas lift or other form of pumping for transferring the fodder from the collecting bag to the surface.
  • the equipment makes it difficult to work with the enclosure in connection with the dayly operation of the breeding plant. Moreover, the collecting bags are less efficient in areas where currents are frequent. Due to the loss of the nutritive value arisen when the fodder has been staying in water for some time, this collected fodder was seldom used a second time and, thus, the fodder loss and waste still represent an economic loss for the breeder, even in cases where pollution is reduced.
  • the object of the invention is to provide a method and a device for detecting loss and waste of fodder.
  • reference numeral 1 denotes a floating enclosure for fish, fodder being supplied from above.
  • a sound transmitter 4 and a hydrophone 6 have been disposed, both connected to an electronic measuring unit 8 and an electronic analyzing unit 10.
  • the measuring unit 8 is adapted to drive the sound transmitter 4, such that sound waves are transmitted in a similar way as known from echo sounders. The sound waves are substantially directed upwardly.
  • the hydrophone 6 is adapted to pick up sound waves within a frequency band comprising the sound frequency transmitted from the sound transmitter 4.
  • the measuring unit 8 is adapted to separate the sound received by the hydrophone 6 into different frequencies and to transfer information concerning existing frequencies to the analyzing unit 10.
  • Fodder, fish and other objects occupying positions above the sound transmitter 4 will reflect some of the transmitted sound energy picked up by the hydrophone 6 in a manner corresponding to that of an echo sounder.
  • Objects moving in a direction towards or away from the sound transmitter 4, i.e. vertically, will additionally cause a change of frequency, the socalled Doppler effect.
  • the frequency distribution of the received sound signal becomes a measure of vertical movement of objects located above the sound transmitter 4.
  • Fish fooder has a characteristic speed of sinking, frequently very low, and the analyzing unit 10 is adapted to react to frequencies correspondingly above the sound frequency transmitted by the sound transmitter 4.
  • the analyzing unit 10 which advantageously can be realized by means of microprocessor electronics, is adapted to weigh the intensity of the existing sound frequencies and, on the basis thereof, to give a signal about fodder loss/waste upon a predetermined occurence of frequencies higher than the sound frequency transmitted.
  • the analyzing unit 10 can advantageously be adapted to react only to sound waves reflected from objects located within a restricted area 12 from the hydrophone 6. As known per se, the distance is measured by measuring the running time for the sound from the sound transmitter 4. By measuring the occurence of sinking objects at several distances from the hydrophone 6, the analyzing unit 10 can compute how large a share of the fodder supplied to the fish that has been lost and, thus, give a graded signal to the automatic feeding machine, which can reduce the allottment of fodder correspondingly.
  • the sound transmitter 4 and the hydrophone 6 are positioned below the enclosure 1, and the hydrophone 6 is adapted to react to approaching fodder particles.
  • the sound transmitter 4 and the hydrophone 6 can be directed downwardly and be positioned adjacent the surface.
  • the analyzing unit 10 it is also possible to adapt the analyzing unit 10 to react to objects moving away from the hydrophone 6, and to position the sound transmitter 4 and the hydrophone 6 accordingly.
  • the current direction is varying, it might be necessary to dispose several sound transmitters 4 and/or a plurality of hydrophones 6, and to read the one or the ones best suited according to the current direction prevailing at the moment.
  • the sound transmitter 4 and the hydrphone 6 will be built together forming one unit.
  • Information may, if desired, be transferred wirelessly between the measuring unit 8 and the sound transmitter 4 respectively the hydrophone 6 by means of sound signals or electromagnetic signals having an appropriate frequency, including light and radio waves.

Landscapes

  • Life Sciences & Earth Sciences (AREA)
  • Environmental Sciences (AREA)
  • Marine Sciences & Fisheries (AREA)
  • Zoology (AREA)
  • Animal Husbandry (AREA)
  • Biodiversity & Conservation Biology (AREA)
  • Farming Of Fish And Shellfish (AREA)
  • Investigating Or Analyzing Materials By The Use Of Ultrasonic Waves (AREA)
  • Measurement Of Velocity Or Position Using Acoustic Or Ultrasonic Waves (AREA)
  • Feeding And Guiding Record Carriers (AREA)
  • Control Of Motors That Do Not Use Commutators (AREA)
  • Electrophonic Musical Instruments (AREA)

Abstract

A method and a device for detecting fodder waste/loss within a fish enclosure (1), where a sound transmitter (4) and a hydrophone (6) are disposed as an upwardly directed echo sounder close to the bottom of the enclosure (1). Sound echos from objects situated above the sound transmitter (4), are picked up by the hydrophone (6). A measuring unit (8) separates signals from the hydrophone (6) into various frequency bands close to the transmitted sound frequency. The distance and amount of the objects are determined in a way similar to the one used in echo sounders. Sinking objects will cause reflected sounds having frequencies slightly higher than the transmitted frequency, so called Doppler effect, and the frequency difference is a measure of the sinking speed of the object. An analyzing unit (10) emphasizes frequencies corresponding to a characteristic sinking speed for the actual type of fodder (2) and gives signals about fodder waste/loss when a predetermined minimum amount of objects having the characteristic sinking speed are detected within a predetermined distance area.

Description

Feed waste detector
The invention relates to a method and a device for detecting fodder loss and waste in connection with the breeding of fish.
Fodder loss and waste represent great losses of value in the breeding of fish and, moreover, fodder loss and waste result in pollution. It is important to the breeder to utilize the growth potential of the fish as good as possible, and to achieve this, the allott ent of fodder must be close to maximum. External environmental changes, e.g. the seeping in of colder water, may rapidly reduce the appetite of the fish, thus causing excess feeding, resulting in fodder loss and waste, especially when automatic feeding machines are used. It is known to control the feeding in relation to water temperature and other factors, but these measures have not been sufficient to avoid waste and loss of fodder. One has tried to measure the appetite of the fish as a function of its activity and reaction to feeding, but this approach has not given a satisfactory result either. Therefore, a need for a device capable of detecting fodder loss and waste directly in order to reduce the supply of fodder, has existed since a long time ago. Several devices for detecting waste and loss of fodder have been tried out. A known detecting device utilizes an echo sounder principle combined with a computer analyzing a relatively complex echo sounder image, but this device has not spread, firstly because it is too expensive and secondly because it does not give a reliable detection. The pollution problem was reduced upon the arrival of devices collecting fodder not eaten. Such devices for collecting fodder comprise a bag which is attached beneath the "fence" enclosung the fish. Also, it is known to dispose risers with gas lift or other form of pumping for transferring the fodder from the collecting bag to the surface. The equipment makes it difficult to work with the enclosure in connection with the dayly operation of the breeding plant. Moreover, the collecting bags are less efficient in areas where currents are frequent. Due to the loss of the nutritive value arisen when the fodder has been staying in water for some time, this collected fodder was seldom used a second time and, thus, the fodder loss and waste still represent an economic loss for the breeder, even in cases where pollution is reduced.
The object of the invention is to provide a method and a device for detecting loss and waste of fodder.
The object is obtained through features as defined in the following claims.
An examplary embodiment of the invention is described in the following with reference to the attached drawing.
In the figure, reference numeral 1 denotes a floating enclosure for fish, fodder being supplied from above. In the bottom or close to the bottom of the enclosure 1, possibly beneath the enclosure if it has a net bottom, a sound transmitter 4 and a hydrophone 6 have been disposed, both connected to an electronic measuring unit 8 and an electronic analyzing unit 10. The measuring unit 8 is adapted to drive the sound transmitter 4, such that sound waves are transmitted in a similar way as known from echo sounders. The sound waves are substantially directed upwardly. The hydrophone 6 is adapted to pick up sound waves within a frequency band comprising the sound frequency transmitted from the sound transmitter 4. The measuring unit 8 is adapted to separate the sound received by the hydrophone 6 into different frequencies and to transfer information concerning existing frequencies to the analyzing unit 10.
Fodder, fish and other objects occupying positions above the sound transmitter 4, will reflect some of the transmitted sound energy picked up by the hydrophone 6 in a manner corresponding to that of an echo sounder. Objects moving in a direction towards or away from the sound transmitter 4, i.e. vertically, will additionally cause a change of frequency, the socalled Doppler effect. Thus, the frequency distribution of the received sound signal becomes a measure of vertical movement of objects located above the sound transmitter 4.
Fish fooder has a characteristic speed of sinking, frequently very low, and the analyzing unit 10 is adapted to react to frequencies correspondingly above the sound frequency transmitted by the sound transmitter 4. The analyzing unit 10 which advantageously can be realized by means of microprocessor electronics, is adapted to weigh the intensity of the existing sound frequencies and, on the basis thereof, to give a signal about fodder loss/waste upon a predetermined occurence of frequencies higher than the sound frequency transmitted.
In order to avoid that sinking fodder close to the surface causes the development of a signal about fodder waste/loss, the analyzing unit 10 can advantageously be adapted to react only to sound waves reflected from objects located within a restricted area 12 from the hydrophone 6. As known per se, the distance is measured by measuring the running time for the sound from the sound transmitter 4. By measuring the occurence of sinking objects at several distances from the hydrophone 6, the analyzing unit 10 can compute how large a share of the fodder supplied to the fish that has been lost and, thus, give a graded signal to the automatic feeding machine, which can reduce the allottment of fodder correspondingly.
In the examplary embodiment, the sound transmitter 4 and the hydrophone 6 are positioned below the enclosure 1, and the hydrophone 6 is adapted to react to approaching fodder particles. In connection with floating fodder which is allotted from below, the sound transmitter 4 and the hydrophone 6 can be directed downwardly and be positioned adjacent the surface. Of course, it is also possible to adapt the analyzing unit 10 to react to objects moving away from the hydrophone 6, and to position the sound transmitter 4 and the hydrophone 6 accordingly. In areas subjected to strong current, it may be necessary to place the sound transmitter 4 and the hydrophone 6 such that the fodder will be moving as straight as possible towards the hydrophone 6 or as straight as possible away from the same. If the current direction is varying, it might be necessary to dispose several sound transmitters 4 and/or a plurality of hydrophones 6, and to read the one or the ones best suited according to the current direction prevailing at the moment.
Normally, the sound transmitter 4 and the hydrphone 6 will be built together forming one unit. Information may, if desired, be transferred wirelessly between the measuring unit 8 and the sound transmitter 4 respectively the hydrophone 6 by means of sound signals or electromagnetic signals having an appropriate frequency, including light and radio waves.

Claims

C l a i m s
1. A method for detecting fodder waste/loss in connection with the breeding of fish, c h a r a c t e r i z e d i n that vertical speed of objects situated at a distance beneath the surface of the water within the area of feeding, is measured, and that fodder waste/loss is signaled when the amount of objects exhibiting a substantially vertical speed corresponding to the sinking speed of the fooder in water, exceeds a predetermined value.
2. A method as set forth in claim 1, c h a r a c t e r i z e d i n that the vertical speed is measured for objects situated within a limited area of distances from a hydrophone (6) which, together with a sound transmitter (4) , is utilized during the speed measurement.
3. A device for carrying out the method as set forth in claim 1, c h a r a c t e r i z e d i n that sound transmitter (4) and hydrophone (6) are positioned below or above the feeding area and are connected to a measuring unit (8) assigned an analyzing unit (10) , the analyzing unit (10) being adapted to transmit sound signals through the sound transmitter (4) , and to receive sound signals from the hydrophone (6) and, further, to be adapted to react to sound frequencies higher or lower than the sound frequency transmitted by the sound transmitter (4) .
PCT/NO1995/000209 1994-11-10 1995-11-08 Feed waste detector WO1996015663A1 (en)

Priority Applications (5)

Application Number Priority Date Filing Date Title
US08/836,728 US5978315A (en) 1994-11-10 1995-11-08 Feed waste detector
AU39391/95A AU3939195A (en) 1994-11-10 1995-11-08 Feed waste detector
CA002204907A CA2204907C (en) 1994-11-10 1995-11-08 Feed waste detector
JP8516372A JPH10512743A (en) 1994-11-10 1995-11-08 Feeding waste detector
EP95937228A EP0802723B1 (en) 1994-11-10 1995-11-08 Feed waste detector

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
NO944276 1994-11-10
NO944276A NO180611C (en) 1994-11-10 1994-11-10 Procedure for detecting feed spill

Publications (1)

Publication Number Publication Date
WO1996015663A1 true WO1996015663A1 (en) 1996-05-30

Family

ID=19897619

Family Applications (1)

Application Number Title Priority Date Filing Date
PCT/NO1995/000209 WO1996015663A1 (en) 1994-11-10 1995-11-08 Feed waste detector

Country Status (8)

Country Link
US (1) US5978315A (en)
EP (1) EP0802723B1 (en)
JP (1) JPH10512743A (en)
AU (1) AU3939195A (en)
CA (1) CA2204907C (en)
ES (1) ES2177664T3 (en)
NO (1) NO180611C (en)
WO (1) WO1996015663A1 (en)

Cited By (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
GB2322701A (en) * 1997-02-26 1998-09-02 Thomson Marconi Sonar Limited Apparatus for detecting the quantity of particles in a fluid medium
US6000362A (en) * 1995-11-24 1999-12-14 Aquasmart Pty Ltd Feeding system for cultured species
FR2781644A1 (en) * 1998-07-30 2000-02-04 Centre Nat Rech Scient PROCESS FOR FEEDING AQUATIC ANIMALS
WO2001010201A1 (en) * 1999-08-07 2001-02-15 Biosonics, Inc. Aquaculture feeding monitor
CN107422303A (en) * 2017-05-24 2017-12-01 青岛越洋水处理设备工程有限公司 Full-automatic bait-throwing method based on acoustic location and IMAQ

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* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2013086514A1 (en) 2011-12-08 2013-06-13 Pentair Water Pool And Spa, Inc. Aquaculture pump system and method
CN103070126B (en) * 2013-01-17 2014-06-11 中国水产科学研究院渔业机械仪器研究所 Pond culture sound control feeding method and device based on same
EP2969158A4 (en) 2013-03-14 2016-12-21 Pentair Water Pool & Spa Inc Carbon dioxide control system for aquaculture
WO2014145661A1 (en) 2013-03-15 2014-09-18 Pentair Water Pool And Spa, Inc. Dissolved oxygen control system for aquaculture
WO2016056923A1 (en) * 2014-10-07 2016-04-14 Norseaqua As Instrument suspension for a dived instrument and use of the suspension
US10694722B1 (en) 2015-05-21 2020-06-30 Atlantic Sapphire IP, L.L.C. Systems and methods of intensive recirculating aquaculture
US11627729B2 (en) 2015-05-21 2023-04-18 Atlantic Sapphire Ip, Llc Transfer assembly and system for aquaculture
US11596132B2 (en) 2015-05-21 2023-03-07 Atlantic Sapphire Ip, Llc Transfer assembly and system for aquaculture
US11484015B2 (en) 2015-05-21 2022-11-01 Atlantic Sapphire Ip, Llc Systems and methods of intensive recirculating aquaculture
CN106614152B (en) * 2017-03-02 2019-10-25 武汉大学 A kind of outstanding multiway tree sensor array based on Fish behavior mode
US10959411B2 (en) 2018-01-04 2021-03-30 Atlantic Sapphire IP, L.L.C. Bottom grading apparatuses for aquaculture systems
JP7165635B2 (en) * 2019-08-29 2022-11-04 グローブライド株式会社 Bait storage device capable of detecting external bait position and bait position detection system
US11425895B2 (en) 2020-03-05 2022-08-30 Atlantic Sapphire Ip, Llc Method for optimization of filtration in an aquaculture system
KR102543563B1 (en) * 2020-12-21 2023-06-15 한국해양과학기술원 An optimal automatic feeding system and method at aquaculture fish farm using multiple underwater sensors
US11662291B1 (en) 2021-02-03 2023-05-30 Atlantic Sapphire Ip, Llc System and method for feed validation measurement
KR102496109B1 (en) * 2022-02-25 2023-02-06 한서대학교 산학협력단 Shrimp farm

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SE444881B (en) * 1985-06-04 1986-05-20 Goran Bjorkland Procedure and arrangement for feeding fish, involving the detection of non consumed feed
WO1992012628A1 (en) * 1991-01-18 1992-08-06 Bentech Subsea A/S Process and device for monitoring feeding by fish and use of said device

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US3879697A (en) * 1970-08-07 1975-04-22 Joseph D Richard Wide angle fish detector
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US3761909A (en) * 1971-12-30 1973-09-25 Delta Products Inc Intrusion alarm system
US3867719A (en) * 1972-03-24 1975-02-18 John W Perrin Relative movement responsive siren alert
US3805224A (en) * 1972-11-24 1974-04-16 Alpine Geophysical Ass Inc Method and apparatus for monitoring biological activity
US4901245A (en) * 1987-12-01 1990-02-13 Moore Technologies, Inc. Nonintrusive acoustic liquid level sensor

Patent Citations (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
SE444881B (en) * 1985-06-04 1986-05-20 Goran Bjorkland Procedure and arrangement for feeding fish, involving the detection of non consumed feed
WO1992012628A1 (en) * 1991-01-18 1992-08-06 Bentech Subsea A/S Process and device for monitoring feeding by fish and use of said device

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AKUSTISK MALNING AV FISKEFOR, TONE BERG, Bentech A/S, pages 4, 6, 24, 34, 36. *

Cited By (11)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US6000362A (en) * 1995-11-24 1999-12-14 Aquasmart Pty Ltd Feeding system for cultured species
US6443098B1 (en) 1995-11-24 2002-09-03 Aquasmart Pty Limited Feeding system for cultured species
GB2322701A (en) * 1997-02-26 1998-09-02 Thomson Marconi Sonar Limited Apparatus for detecting the quantity of particles in a fluid medium
FR2781644A1 (en) * 1998-07-30 2000-02-04 Centre Nat Rech Scient PROCESS FOR FEEDING AQUATIC ANIMALS
WO2000005944A1 (en) * 1998-07-30 2000-02-10 Centre National De La Recherche Scientifique (Cnrs) Method for feeding aquatic animals
AU751628B2 (en) * 1998-07-30 2002-08-22 Centre National De La Recherche Scientifique (Cnrs) Method for feeding aquatic animals
US6510815B1 (en) 1998-07-30 2003-01-28 Centre National De La Recherche Scientifique (Cnrs) Method for feeding aquatic animals
WO2001010201A1 (en) * 1999-08-07 2001-02-15 Biosonics, Inc. Aquaculture feeding monitor
GB2367229A (en) * 1999-08-07 2002-04-03 Biosonics Inc Aquaculture feeding monitor
GB2367229B (en) * 1999-08-07 2003-09-17 Biosonics Inc Aquaculture feeding monitor
CN107422303A (en) * 2017-05-24 2017-12-01 青岛越洋水处理设备工程有限公司 Full-automatic bait-throwing method based on acoustic location and IMAQ

Also Published As

Publication number Publication date
US5978315A (en) 1999-11-02
CA2204907A1 (en) 1996-05-30
ES2177664T3 (en) 2002-12-16
NO944276L (en) 1996-05-13
EP0802723B1 (en) 2002-05-22
EP0802723A1 (en) 1997-10-29
CA2204907C (en) 2004-01-20
AU3939195A (en) 1996-06-17
NO180611C (en) 1997-05-21
NO180611B (en) 1997-02-10
JPH10512743A (en) 1998-12-08
NO944276D0 (en) 1994-11-10

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