NO20230241A1

NO20230241A1 - A device and method for sorting fish in a flow of swimming fish

Info

Publication number: NO20230241A1
Application number: NO20230241A
Authority: NO
Inventors: Sindre Abrahamsen
Original assignee: Biosort As
Priority date: 2023-03-07
Filing date: 2023-03-07
Publication date: 2024-09-09
Also published as: CL2024000659A1; CA3230412A1; GB202402956D0; NO348292B1; GB2630170A

Description

The invention concerns a device for sorting fish in a flow of swimming fish.

Presently, the fish farming industry is a huge industry which is competitive vis a vis other food production from animals. The industry is relatively new, and its ambition is to grow steeply in the years ahead. Today, the industry is characterized by manua l operations and the level of precision is low in areas such as counting fish, measurement of biomass, sea lice counting, disease surveillance as well as monitoring fish health and growth.

Today, a 15-20% loss of fish during a production cycle is not uncommon, and this leads to great economic losses, poor utilization of resources, poor utilization of feed, higher discharge of nutrient salts as well as poor well-being of fish (“Tap av Laksefisk i Sjø”, Hogne Bleie, 2014). Sea lice and several contagious diseases are increasing problems for the industry. Resistance is a known phenomenon with excessive use of chemicals or medications on whole populations of a species.

The treatment regimens of today are mainly applied to fish in a fish pen, which means that up to 200000 fish receives the same treatment. The treatment can be medication, use of chemicals, mechanical treatment or slaughter. The consequence of this is increased risk of resistance, as well as unneccesary discharge of chemicals and drugs.

The treatment methods of present also often result in the need to starve fish, concentrating operations as well as pumping to another fish pen or well boat. A concentrating operation comprises making the available volume for fish to swim in smaller. This may for instance be done by decreasing the volume in the fish pen, and in this way increase the density of fish. This may for example be done to concentrate the fish in an area for treatment in the fish pen, or to concentrate the fish for transfer to a well boat using a suction hose.

Often, a well boat has an integrated method of concentrating the fish when live fish is to be unloaded. This may for instance be a bulkhead which can be moved through the well in the boat holding the fish. This bulkhead is moved through the well to concentrate the fish against the part of the well from which the fish is discharged.

These treatments inflict stress on the fish, damage and possible loss of mucous layer. The mucous layer (mucosal epithelia) has been proved to be important to the fish’ resistance to sea lice and pathogens, and loss of mucous layer makes the fish more vulnerable than from wounds.

Presently, assessment of fish health in the fish farming industry is primarily based on manual solutions; ether directly using landing nets for collecting fish and manual inspection, and possible sampling, possibly using a submerged camera and inspecting the images manually. Automatic solutions for analyzing fish health or solutions making it possible to follow single individuals over time is not established, and no solutions for sorting out individual fish exists. Today, different automatic systems for measuring biomass are available; however, these have an high error margin, and the industry is interested in solutions providing biomass measurements with greater accuracy.

NO331843 discloses a method and system for recognition, treatment, sorting, and documenting live fish. The main purpose of the system is vaccination of fish, and the possibility of being able to control the vaccination, possibly sort out undesired fish before vaccination. The system uses image recognition of fish which are transported on a conveyor belt in connection with the vaccination.

This and other devices and methods can be used for identifying characteristic features of the fish. In this context, there is often a need for discerning fish from each other physically, for example if there is a need to sort diseased fish from healthy fish, fish of low weight into a separate area for farming; fish with proper slaughter weight can be picked out for further processing, etc.

Other areas where there is a use for identifying and sorting out individuals or groups that have a specific characteristic can be salmon swimming up rivers to spawn. Due to new species that have been introduced or that are spreading to new areas, there exists a need for identifying the species and possibly the health of the fish swimming up the river and sorting out the individuals that should be allowed to progress and individuals that should be removed from the river.

NO341960 describes a device for sorting fish in a flow of swimming fish which comprises a sorting chamber and at least one conveying device with a guide element which can be moved inside the sorting chamber in order to push the fish towards a selected outlet port.

This device is adapted to guide the whole amount of fish that is present inside the sorting chamber at the time and lead all of them towards the same outlet port.

However, if it is required to choose some of the fish inside the sor ting chamber to be directed to one outlet port and other fish to another outlet port, this device is not suitable.

The object of the invention is to provide a device which in an efficient and careful way can sort out individual fish from a group of fish.

The object of the invention is achieved by the features of the patent claims.

In one embodiment of the invention, a device for sorting fish in a stream or flow of swimming fish comprises a sorting chamber having an inlet port and at least two outlet ports allowing fish to enter and exit the sorting chamber and at least one conveying device comprising at least one guide element configured to be movable to form an enclosed sub-volume of the sorting chamber.

The sorting chamber is a unit comprising a volume where the fish can swim freely until they are enclosed in a sub-volume of the sorting chamber volume by means of the conveying device. The inlet and outlet ports may have different size and may be arranged at sides and/or in the top/and bottom walls of the sorting chamber. Each outlet port can lead the fish to a desired area for further processing, such as for example disease treatment, slaughter, holding for further growth, etc.

The conveying device may be any suitable device or combination of elements that can form an enclosed sub-volume inside the sorting chamber, such as open box, a landing net, scoop net, or one wall or a number of walls that fit together to enclose a volume, one or more fences, poles, posts, blends, roller blinds, etc. In case of a box, landing net or other fixed volumes, the enclosed sub-volume can be formed by moving the conveying device into or partly into the sorting chamber and moving the conveying device to the chosen exit port or aligning an open end of the conveying device with an exit port to let the fish swim through the port voluntarily. For other embodiments of a conveying device, the elements can also be moved into or partly into the sorting chamber for example to partially or fully span the height or width of the sorting chamber and can be moved coordinated or independently into or inside the sorting chamber to enclose the desired sub-volume.

The guide element is configured to be movable to vary the volume of the enclosed sub-volume within the sorting chamber to push the fish toward at least one of the outlet ports. The guide element may be a part that constitutes the conveying device or may be a separate part, for example a wall, a floor element, a roller blind, one or more poles, nets, etc.

The guide element can be configured to be laterally movable, movable between a lower and an upper position, or a combination of those movements.

The guide element and/or the conveying device can be connected to a processing device and adapted to receive signals from the processing device which provide information on how to move the enclosed sub-volume.

The sorting chamber may comprise at least one sensor for monitoring the fish in the sorting chamber. There may also or alternatively be a separate recording area arranged in front of the sorting chamber that comprises sensors for monitoring the fish before they enter the sorting chamber. At least one sensor may comprise an imaging device. The recording area and/or the sorting chamber may be completely or partly localized beneath water.

The device may comprise a processing device and the conveying device may then be adapted to receive signals from the processing device which provide information on how to move the conveying device. The processing device can be configured to analyze the images of the imaging device and based on the analysis determine the movement of the conveying device.

The processing device may be connected to a system for registering and monitoring health and physical development of live fish, comprising at least an imaging device adapted to image a recording area

Figure 1 shows an example of a device for sorting fish.

Figure 2 schematically shows an embodiment of a conveying device.

Figure 3 illustrates an example of device for sorting out fish in a flow of fish used in a system in a fish farming pen with a “lice snorkel” .

Figure 4 shows an example of an embodiment of a device for sorting out fish in a flow of fish.

Figure 5 shows another example of an embodiment of a device for sorting out fish in a flow of fish.

Figure 6 shows yet another example of an embodiment of a device for sorting out fish in a flow of fish.

Figure 1 shows an example of a device for sorting out fish in a flow of fish 10 comprising a sorting chamber 14 having an inlet port 11 and two outlet ports 12, 13. Fish can enter the sorting chamber 14 through the inlet port 11 and exit the sorting chamber through one of the outlet ports 12, 13.

A conveying device 15 is arranged in the sorting chamber 14 and comprises a number of guide elements 17 configured to be movable between a passive and an active position in the sorting chamber. In the active position the guide elements spans the height of the sorting chamber and are laterally movable within the sorting chamber to push the fish towards at least one of the outlet ports , and in the passive position the guide elements are located outside the sorting chamber.

The guide elements may also be movable when they are in the passive position. In this way the guide elements 17 may be positioned below or above the sorting chamber in positions suitable for the fish presently in the sorting chamber before they are moved to the active position and be further moved to guide the fish to the desired destination. This makes it possible to guide selected amounts of fish that are already present in the sorting chamber.

In figure 1 the guide elements 17 are in the active position and are moving sideways within the sorting chamber to guide the fish towards one of the outlet ports 12, 13. In this example, the conveying device 15 comprises several guide elements 17, which can move across the sorting chamber and which are adapted to guide the fish to one of the outlet ports 12, 13, but the conveying device may be other kind of guide element such as a stiff or flexible curtain or other suitable guiding means.

The conveying device 15 is connected to a processing device and can receive signals from the processing device comprising information on how to move the conveying device and thus the guide elements. Such information can for example be to which outlet port the fish is to be guided, which part of the sorting chamber comprises the fish to be moved, etc.

A motor is connected to the conveying device and can move the conveying device and thus the guide elements 17 in accordance with the signals from the processing device 16. The guide elements embrace the fish to be sorted in a specific way, and in a specific speed, such that the fish does not have time to react and bolt past the sorting unit but is caught and sorted out.

The fish entering through the inlet port 11 may for instance arrive from a recording device in which information of the individual fish is recorded. In other embodiments, the sorting chamber may comprise a recording device and/or may comprise one or more sensors for recording environmental characteristics and other information on the sorting chamber and the fish in the sorting chamber.

The recording device and/or sensor may comprise an imaging device, such as a camera, for recording images of the interior of the sorting chamber. The images can be analyzed to provide information about the fish in the sorting chamber, such as species, size, possible injuries, infections, the presence of parasites, etc.

This information is used by the processing device to decide which outlet port the fish shall be guided to. Based on this information, the guide elements 17 are moved through the sorting chamber 14 in such a way that the fish in a gentle manner is guided towards the desired outlet port. The guide elements can either be controlled to be idle and allow the fish to swim straight ahead, or can be shifted sideways, i.e., transverse to the sorting direction, and thus, the fish is moved sideways. In the example in figure 1, the guide elements are about to guide the fish towards the outlet port 12, as the guide elements close to the head and tail parts of the fish moves slightly faster than the guide elements at the middle part of the fish, such that the fish is embraced, and the fish in the front and rear are caught by the conveying device.

Figure 2 schematically shows an embodiment of the conveying device, for example for use in the example of Figure 1. The conveying device 20 comprises guide elements 25 arranged to be moved between an active position and a passive position. In figure 2a, the guide elements are in the passive position, lowered below the floor 27 of the sorting chamber. The floor 27 has parallel slots 29 into which the guide elements can enter and exit the sorting chamber. In figure 2b the guide elements 25 are in an intermediate position between the active and passive position. This is normally a transitional position but may in some embodiments be the active position. In figure 2c, the guide elements 25 have completely entered the sorting chamber in an active position.

Figure 3 shows an example of an embodiment of the invention used in a system in a fish farming pen with a “lice snorkel”. In this system, the fish swim upwards in the lice snorkel 39, and is guided into a device 36 for recording and monitoring health and physical development of the fish. The recording device comprises a recording area 37, a data processor, and a guiding device to guide fish through the recording area. One or more imaging devices images the recording area, and a data processor analyzes images from the imaging device and identifies features of the fish present in the recording area. Then, the fish swims from the recording area through the inlet port to the sorting chamber 30. In the sorting chamber, the conveying device 35, shown here in the passive position, is controlled such that the fish is guided to the desired outlet port. Each outlet port leads the fish to a desired area for further processing, such as for example disease treatment, slaughter, holding for further growth, etc.

Figure 4 shows an example of an embodiment of the invention. In this figure there are fish 41 present in the sorting chamber 40, and several guide elements 45 are in an active position within the sorting chamber. In this embodiment the guide elements 45 are moved up through parallel slots 42 in the floor 43. The guide elements 45 can be positioned in the desired position below the floor while in an passive position before being moved up to the active position as seen in the figure. The guide elements 45 can then move along the slots in order to guide the fish as desired. In this embodiment, the sorting chamber may comprise a recording device for recording and monitoring health and physical development of the fish. The recording device comprises at least one imaging device, a recording area which in this case is the sorting chamber and a data processor. The imaging device records images of the sorting chamber, the data processor analyzed the images and controls the guide elements according to the result of the analysis. The images may for example be used to determine where the fish having specific characteristics are located in order to move the guide elements up into the sorting chamber in the correct positions and further move the guide elements within the sorting chamber to guide the fish to their selected destination.

Figure 5 shows an example of a device for sorting fish in a flow of swimming fish that comprises a sorting chamber 54 having an inlet port 51 and at least two outlet ports 52, 53, allowing fish to enter and exit the sorting chamber, respectively. A conveying device 56 comprising a guide element 57 is movable to form an enclosed sub-volume of the sorting chamber.

A motor can be connected to the conveying device and the guide element and can move the conveying device and the guide element 57 in accordance with signals from a processing device. The guide elements embrace the fish to be sorted with a speed adapted such that the fish does not have time to react and bolt past the sorting unit but is caught and sorted out.

In this example, the conveying device is box-shaped with open ends and side walls. The open ends face upwards and downwards and the conveying device 56 is movable up and down into and out of the sorting chamber, respectively. When the conveying device 56 is moved up into the sorting chamber 54, the volume inside the conveying device encloses a sub-volume of the sorting chamber 54. When there are one or more fish in the sorting chamber, the fish located in the part of the sorting chamber that becomes enclosed by the conveying device 56, ie. in the enclosed subvolume, will be captured inside the conveying device and guided towards the outlet port 53 that is located directly above the conveying device 56. The guide element 57 is arranged inside the conveying device 56, perpendicular to the side walls of the conveying device and can be moved in a vertical direction and thereby changes the sub-volume enclosed by the conveying device. In this way, any fish inside the enclosed sub-volume is encouraged gently to swim towards and through the outlet port 53.

The control of the conveying device and the guide element is done by means of a processing device connected to the a motor controlling the guiding element and the conveying device adapted to receive signals from the processing device which provide information on how to vary the volume of the enclosed sub-volume.The device may be a part of a system similar to the one illustrated and described in figure 3. One or more imaging devices images the recording area, and a data processor analyzes images from the imaging device and identifies features of the fish present in the recording area. Then, the fish swims from the recording area through the inlet port 51 to the sorting chamber 54. In the sorting chamber, the conveying device then is controlled such that the fish is guided to the desired outlet port.

Each outlet port leads the fish to a desired area for further processing, such as for example disease treatment, slaughter, holding for further growth, etc .

Figure 6a-6c shows another example of a device for sorting fish in a flow of swimming fish that comprises a sorting chamber 64 having an inlet port 61 and at least two outlet ports 62, 63, allowing fish to enter and exit the sorting chamber, respectively. A conveying device 66 comprising a guide element 67 is movable to form an enclosed sub-volume of the sorting chamber. In this example, the conveying device comprises three movable walls 67, 68, where two walls 68 can move parallel to the sides of the sorting chamber and one wall 67, here being the guide element, can move up into the sorting chamber. The conveying device 66 is thus movable into and out of the sorting chamber. When the walls 67, 68 of the conveying device 66 is moved into the sorting chamber 64, the volume enclosed by the walls, and thus by the conveying device, encloses a sub-volume of the sorting chamber 64.

When there are one or more fish in the sorting chamber, the fish located in the part of the sorting chamber that becomes enclosed by the conveying device 66, ie. in the enclosed sub-volume, will be captured inside the conveying device for further guiding to one of the outlet ports.

In figure 6a, there is illustrated a situation where the conveying device is positioned outside the sorting chamber 64, with walls 68 retracted out in a horizontal direction and wall 67 retracted vertically to a position below the sorting chamber. As can be seen, a fish is outside the sorting chamber, but is on its way to swim into the sorting chamber. In figure 6b, the walls 67, 68 are in the process of being moved into the sorting chamber, thus enclosing a sub-volume of the sorting chamber. The fish is now present in the sub-volume that is being enclosed by the movement of the conveying device.

The guide element 67 is movable inside the conveying device 66, perpendicular to the side walls of the conveying device and can be moved in horizontal direction and thereby changes the sub-volume enclosed by the conveying device. In this way, any fish inside the enclosed sub-volume is encouraged gently to swim towards and through the outlet port 63.

In figure 6c, the conveying device completely encloses a sub-volume of the sorting chamber 64 and the guide element 67 has moved in a direction towards the outlet opening, thereby guiding the fish towards the outlet port 63.

A motor can be connected to the conveying device and the guide element and can move the conveying device and the guide element 57 in accordance with signals from a processing device.

The control of the conveying device and the guide element is done by means of a processing device connected to the a motor controlling the guiding element and the conveying device adapted to receive signals from the processing device which provide information on how to vary the volume of the enclosed sub-volume.

The device may be a part of a system similar to the one illustrated and described in figure 3. One or more imaging devices images the recording area, and a data processor analyzes images from the imaging device and identifies features of the fish present in the recording area. Then, the fish swims from the recording area through the inlet port 61 to the sorting chamber 64. In the sorting chamber, the conveying device then is controlled such that the fish is guided to the desired outlet port.

Claims

1. Device for sorting fish in a flow of swimming fish, comprising:

- a sorting chamber having an inlet port and at least two outlet ports allowing fish to enter and exit the sorting chamber, and

- at least one conveying device comprising at least one guide element configured to be movable to form an enclosed sub-volume of the sorting chamber,

- wherein the conveying device is connected to a processing device and adapted to receive signals from the processing device which provide information on how to move the enclosed sub-volume.

2. Device according to claim 1, where the guide element is configured to be movable to vary the volume of the enclosed sub-volume within the sorting chamber to push the fish toward at least one of the outlet ports .

3. Device according to claim 1 or 2, where the conveying device comprises at least two movable walls, where one wall is the guide element.

4. Device according to one of claims 1-3, where the guide element is movable within the enclosed sub-volume.

5. Device according to one of the previous claims, where the guide elements comprise at least one wall that spans at least partially the height of the sorting chamber.

6. Device according to one of the previous claims, where the sorting chamber comprises at least one sensor for monitoring the fish in the sorting chamber.

7. Device according to claim 6, where the at least one sensor comprises an imaging device.

8. Device according to one of the claims 2-7, comprising a processing device and where the guide element is adapted to receive signals from the processing device which provide information on how to move the guide element.

9. Device according to claim 7, where the processing device is configured to analyze the images of the imaging device and based on the analysis determine the movement of the conveying device.

10. Device according to claims 7, wherein the recording area and/or the sorting chamber is completely or partly localized beneath water.

11. Method for sorting fish in a flow of swimming fish, comprising:

- allowing fish to enter and exit a sorting chamber having an inlet port and at least two outlet ports,

- moving at least one conveying device comprising at least one guide element to form an enclosed sub-volume of the sorting chamber,

- where the conveying device is connected to a processing device and receive signals from the processing device which provide information on how to move the enclosed sub-volume.

12. Method according to claim 10, where the guide element is moved to vary the volume of the enclosed sub-volume within the sorting chamber to push the fish toward at least one of the outlet ports.

13. Method according to one of claims 10 or 11, where the guide element is moved within the enclosed sub-volume.

14. Method according to one of claims 10-13, comprising capturing images of fish in the sorting chamber, analyzing the images, and based on the analysis determine the movement of the conveying device.