NO343135B1 - APPARATUS FOR INJURYING AN EXTERNAL PARASITE ON A FISH - Google Patents

Abstract

Apparatus (1) for damaging an external parasite on a fish, the apparatus (1) comprising a submersible hull (10) provided with an energy system (20), a propulsion system (30) and a navigation system (50), wherein the apparatus (1) further, means for identifying aquatic organisms include a control system (90) adapted to move the apparatus (1) to a proximity of the fish or parasite, and a tool (82) adapted to harm the parasite.

Description

APPARATUS FOR MAINTAINING AN EXTERNAL PARASITE ON A FISH

The invention relates to an apparatus for neutralizing an external parasite on a fish. More specifically, the invention relates to an apparatus comprising a submersible hull or framework provided with an energy system, a propulsion system and a navigation system, where the apparatus includes means for identifying parasites and fish, a control system arranged to move the apparatus to a vicinity of the parasite or fish, and a tool designed for neutralizing the parasite.

Background of the invention and prior art

Salmon louse (Lepeophtheirus salmonis) is a common parasite on salmon and lives and reproduces on salmon and trout in salt water. Salmon lice inflict wounds on the fish which can cause infections, problems with the salt balance and reduce the fish's growth. Lice larvae that are in the infective stage occur primarily in the top 10 meters below the water surface. Harmful algae that can secrete toxins also occur in the upper part of the water column.

Salmon in floating farms are particularly susceptible to salmon lice. Salmon have an open swim bladder and the salmon must therefore rise to the surface of the water to swallow air for the swim bladder. Consequently, for shorter or longer periods, salmon must stay in the upper part of the water column where the concentration of salmon lice is greatest.

Treatment of salmon lice is mainly done by using chemicals that are mixed into the water, so-called bath treatment, or by mixing an active substance into the feed. The feed is spread over the water surface and sinks down into the water column. The treatment may have a negative impact on the environment. Salmon lice can build up resistance to the drugs used, and the treatment is resource-intensive and expensive. Bath treatment also causes the fish to become stressed and have increased mortality. The treatment also covers the growth of the fish during the treatment period.

External crustacean parasites, of which salmon lice are an example, can also be combated with so-called cleaner fish that remove and eat external parasites in other larger fish, such as salmon. The most commonly used types of cleaner fish are wild-caught wrasse and farmed roe bream. Access to wild-caught wrasse is largely dependent on the wild fish population, seasons and disease. High demand for wrasse means that there is a danger of overfishing of wrasse. The wrasse is also sensitive to temperature and therefore unsuitable at low temperatures.

The amount of cleaner fish in a breeding pen can amount to about 20 per cent of the number of breeding fish in the breeding pen. In a breeding pen with 10,000 breeding fish, there can therefore be around 2,000 cleaning fish. Studies show that as little as 10 to 15 percent of cleaner fish feed effectively on farmed fish infected with salmon lice. The rest of the cleaner fish graze on other fish, fouling on the breeding cage or it eats other organisms in the water. The low efficiency makes the use of cleaner fish expensive, at the same time cleaner fish can have a negative environmental impact in the breeding cage.

Patent document NO304171 describes a device for removing parasites from the outside of a fish, particularly salmon lice. The fish is introduced into a stream of water where the fish is exposed to water jets from nozzle heads or nozzle slits directed at its circumference. One disadvantage of this method is that the fish become stressed.

Patent document NO335947 describes a device for a lice sail around a breeding cage. The lice sail is strung up between the upper edge of the breeding cage and a submerged frame around the breeding cage, so that the lice sail has an angle of up to 45 degrees. The sail extends to a depth below the salmon louse's habitat. Disadvantages of this solution are that the lice sail prevents the access of vessels to the breeding cage, and that the lice sail is resource-intensive to assemble and dismantle.

Patent document NO333479 describes a device for isolating a rearing cage against unwanted organisms, by enclosing the rearing cage with a fine-mesh fluid-permeable net. This solution requires fresh water to be pumped into the rearing pen.

Patent document WO2015009160 describes a device for neutralizing ectoparasites in that the device sends an electric pulse that kills or weakens salmon lice. Patent document NO331345 describes a device for neutralizing parasites on a fish, for example salmon lice, using a laser. The device comprises a camera, a system for optical recognition of parasites and a light source arranged to emit pulses with a point-shaped light that is harmful to the parasite in question. The device is stationary and has a relatively large inaccuracy and thereby problems in hitting salmon lice. The question is whether the laser beam can harm the fish if it does not hit the salmon lice and instead, for example, hits the fish's eye.

Patent document NO20130561 describes a device for collecting and destroying lice in water, where a pump sucks in lice and water through slits or openings and into a body, where the mixture of lice and water is fed to a grinder for destruction.

Patent document WO2015043603 describes a pump system for removing parasites from a fish, where the fish is pumped from a first volume to a second volume. Between the first and the second volume, a plurality of nozzles arranged to flush away the parasites are arranged. The loose parasites are separated from the fish by the parasites following the water flow out of the device, while the fish is led down into the other volume.

Patent document WO2016120071 shows a robotic manipulator arm comprising a propulsion system and a tool. The tool can either be an inspection tool with a camera, a manipulation tool or a gripping tool.

The purpose of the invention is to remedy or to reduce at least one of the disadvantages of known technology, or at least to provide a useful alternative to known technology.

The purpose is achieved by the features indicated in the description below and in the subsequent patent claims.

The invention is defined by the independent patent claims. The independent claims define advantageous embodiments of the invention.

General description of the invention

In a first aspect, the invention relates to an apparatus for neutralizing an external parasite on a fish where the apparatus comprises a submersible hull or framework provided with an energy system, a propulsion system and a navigation system, where the apparatus comprises means for identifying parasites and fish, a control system adapted to move the apparatus to a vicinity of the parasite or fish, and a tool adapted to render the parasite harmless. The apparatus can further comprise a fastening device for the tool, where the fastening device can be designed for connecting different tools.

The device will subsequently be referred to as a robotic cleaning fish. Neutralizing an external parasite can be understood as killing the parasite, rendering it ineffective or removing it from the fish. The parasite can be a salmon louse.

The robotic cleaning fish is designed to supplement or replace live cleaning fish in a breeding cage. As described in the introduction, a breeding pen can typically include 2,000 live cleaner fish, of which around 300 cleaner fish graze effectively on salmon lice. The robotic cleaning fish is designed to continuously search for and neutralize salmon lice. A breeding pen can therefore include significantly fewer robot cleaner fish than live cleaner fish. Extensive use of known technology combined with a large production volume can make the robot cleaning fish an economic alternative to live cleaning fish.

The robotic cleaning fish can include known technology taken from a group consisting of underwater vessels, for example ROV (remote operated vehicle) and AUV (autonomous underwater vehicle).

The submersible hull can comprise a main shape with a size corresponding to a fish, thereby affecting the fish in the rearing cage as little as possible. In an alternative embodiment, the robot cleaning fish may comprise an open frame or a frame through which the fish can swim.

The energy system may comprise a battery or a wired energy supply. The battery can be replaceable or rechargeable. A rechargeable battery can be charged manually, for example by taking the robotic cleaning fish out of the water and connecting the battery to a battery charger. In an alternative embodiment, the battery can be charged via an inductive charging system. The inductive charging system can be arranged in the breeding cage and include one or more charging stations. A plurality of charging stations can be arranged at different heights in the water column. A specialist can, based on the number of robotic cleaning fish in the breeding cage and the battery life, calculate how many charging stations are needed in the breeding cage. The battery can be charged automatically by the robot cleaning fish navigating to the charging station when the power level reaches a lower minimum limit. The robot cleaning fish's connection system to the charging station may comprise a cable attached to the robotic cleaning fish, where the cable is provided at its free end with means for connection to the charging station. Means for connection may include a magnet.

The wired energy supply can comprise a power cable which in its first end part is attached to the robotic cleaning fish and in its second end part is attached to an external energy source or another robotic cleaning fish. The energy cable may comprise a cable for communication and a hose for a fluid.

The propulsion system can include means according to known technology, for example a propeller, a water jet or a device for a fish-like movement. The propulsion system may include means for maneuvering, for example a rudder or a thruster according to known technology. Means of propulsion and maneuvering may be shared. A propulsion system comprising a rotatable or a movable component may include means that prevent the fish from coming into contact with the rotatable or movable component.

The navigation system can include means according to known technology, for example a transmitter, a gyrocompass, an acoustic positioning system, or an audiovisual navigation system. The navigation system can be designed to keep a plurality of robotic cleaners within one or more defined areas in the breeding cage. For example, most of the robot cleaning fish can be programmed to stay in the upper part of the water column where the concentration of salmon lice is greatest.

The navigation system may include means for autonomous navigation in the rearing cage or for guiding the robot cleaning fish along a defined path or to a specific point, for example a charging station. The navigation system may include means designed for direct communication between two or more robotic cleaners.

The robotic cleaning fish may comprise a ballast system designed to keep the robotic cleaning fish floating at a specific depth below the water surface. The ballast system can include a ballast tank for water or air. In an alternative embodiment, the ballast system can include one or more ballast weights.

An identification system can include means according to known technology for the identification and tracking of aquatic organisms, for example parasites and fish, and the identification system can include a machine vision comprising generic and standardized algorithms used in drones according to known technology. Current algorithms are so-called mean-shift and camshift. These are algorithms designed to follow a color histogram, provided that the object to be followed, in this case the fish or the parasite, has been identified. The identification system may include algorithms designed to cope with zooming, turning and panning when the fish moves in relation to the robotic cleaning fish. An identification system as described can also include algorithms designed to dynamically adapt to the conditions in the rearing pen by trial and error.

The device can comprise a control system and a software for processing and processing information from said systems and a plurality of sensors arranged on the robot cleaning fish.

The apparatus may comprise a communication system, and the communication system may be arranged for wireless communication between the robot cleaner and an operator and between two or more robot cleaners.

The apparatus may comprise at least one attachment device for a tool or a sensor. The attachment device can be adapted to different tools and sensors. The tool can be designed for mechanical neutralization of the parasite, for monitoring the health of the fish in the breeding cage or for lice counting. The tool can be designed to perform one or more of the aforementioned tasks on a tagged fish. The marking of the fish can, for example, be an RFID chip attached to the fish.

The tool for neutralizing the external parasite may comprise a suction mechanism, a cutting function, an electrical pulse, a light pulse, a sonic pulse with acoustic pressure or a camera. The tool may include several of the aforementioned properties and the tool may include a sensor.

The robotic cleaning fish's sensor system and propulsion system position the robotic cleaning fish correctly in relation to the task the tool is designed to perform. If the tool includes a suction mechanism, the suction mechanism can be designed to enclose the salmon lice and suck on the fish, while another tool renders the salmon lice harmless.

The robotic cleaning fish may include means for counting live and neutralized parasites. The system may also include means for recording the time and position for the identification and removal of parasites. The information can be stored in the control system and transferred to the operator.

In a second aspect, the invention relates to a method for removing external parasites on fish in a breeding pen, where the method comprises the following steps:

a) to provide an apparatus according to the first aspect of the invention;

b) moving the apparatus immersed in the rearing cage;

c) activating an identification system comprising a camera, machine vision and algorithms designed to identify and target parasites;

d) upon detection of a parasite, actuate the control system to position the apparatus to a vicinity of the identified parasite;

e) to neutralize the parasite by activating the tool;

f) to repeat steps b) – e).

The method may further include the steps:

a') to continuously measure the battery current level;

b') to interrupt the device's search and identify parasites according to steps b) - e) when the battery current level reaches a lower limit value;

c') to activate the device's navigation system to autonomously move the device to a nearest charging station;

d') to autonomously connect the device's secondary coil to a primary coil arranged in one of the charging station's docking stations;

e') to recharge the battery;

f') to release the device from the charging station when the battery is charged; and

g') to allow the device (1) to resume search and identification according to steps b) - e).

Execution example

In what follows, an example of a preferred embodiment is described which is illustrated in the accompanying drawings, where:

Fig.1 shows a schematic drawing of the robot cleaning fish, and

Fig.2 shows, on a smaller scale, a schematic drawing of a plurality of robotic cleaners arranged in a breeding cage.

Figure 1 shows a schematic diagram of a robotic cleaning fish 1 comprising a submersible hull 10, an energy system 20, a propulsion system 30, a ballast system 40, a navigation system 50, a communication system 55, a sensor system 60, a light 70, a tool system 80 comprising a tool attachment 81 and a tool 82, and a control system 90.

The submersible hull 10 is shown in the figure with a fish-like design in order to act as one as possible with the fish in a breeding cage 3 indicated in figure 2.

The energy system 20 comprises a rechargeable battery 21 which supplies the robot cleaning fish 1 with electrical energy. The energy system 20 comprises means for control and monitoring of the energy system 20 and associated components. The battery 21 can be charged inductively. When the current level of the battery 21 reaches a lower limit value, the robotic cleaning fish 1 automatically navigates to a submerged charging station 23 attached to the rearing cage 3. The inductive charging takes place by connecting a secondary coil 22 on the robotic cleaning fish 1 to a primary coil on the charging station 23. The secondary coil 22 is attached to the robotic cleaning fish 1 via a flexible cable. In an alternative embodiment, the secondary coil may be attached to the submersible hull 10.

The propulsion system 30 comprises a vertically arranged propeller 31 and a propeller 33 which is horizontally arranged inside the hull and a truster 32 according to known technology. The propeller 33 is arranged horizontally in a central passage in the submersible hull 10, and the propeller 33 is arranged to move the robot cleaning fish 1 vertically in the water column when the propulsion speed is zero. A pair of steering fins 34 is arranged to guide the robot cleaner fish 1 in a vertical direction in the water column when the robot cleaner fish 1 moves forward in the water. The propeller 31, the thruster 32, the vertical propeller 33 and the control fins 34 can be operated individually or simultaneously.

The ballast system 40 regulates the buoyancy of the robot cleaning fish 1. The ballast system 40 comprises a ballast tank 41, a compressed air tank 42 and a valve system 43 according to known technology. When the robot cleaner fish 1 is going to dive, the robot fish 1's control system 90 ensures that the valve system 43 is opened so that the ballast tank 41 can be filled with water until the robot cleaner fish 1 achieves the pre-programmed buoyancy.

When the robot cleaner fish 1 is to rise in the water column or rise to the water surface 5 for service, the valve system 43 ensures that the water in the ballast tank 41 is replaced with air from the compressed air tank 42. To ensure that the robot cleaner fish 1 always reaches the water surface 5, the control system 90 ensures that the ballast tank 41 cannot be filled with more water than compressed air 42 is available to give the robot cleaning fish 1 a positive buoyancy. When there is a need to top up air in the compressed air tank 42, the robot cleaning fish will stay afloat in the waterline 5 and the control system 90 will notify an operator of the need for service.

The navigation system 50 comprises an underwater navigation system according to known technology. The robotic cleaning fish 1 can navigate autonomously or controlled in the rearing cage 3.

The communication system is designed for wireless two-way communication between the robot cleaning fish 1 and a base station 56 placed on the rearing cage 3, indicated in figure 2.

The sensor system 60 comprises several sensors, typically in the form of a pressure sensor, a depth sensor, a temperature sensor, a position sensor, a laser for distance measurement and a means for reading an RFID chip. Furthermore, the robot cleaning fish is equipped with one or more sensors 62 designed for searching for and identifying salmon lice and fish. A camera 65 and a light system 70 are arranged in the front end part 1A of the robot fish 1. The camera 65 is equipped with a machine vision set up for the identification of fish and parasites. The camera 65 and the sensor system 60 are connected to the control system 90.

A fastening device 81 for a tool is arranged in the front end part 1A of the robot cleaning fish 1. The tool 82 is shown in the figure with a suction mechanism arranged to enclose the salmon lice. The tool 82 is internally provided with a device designed to kill salmon lice by means of an electric pulse.

All the functions of the robot cleaning fish 1 and the functions of the tool 82 are controlled by the control system 90.

Figure 2 shows, on a smaller scale, a principle sketch of a breeding cage 3 comprising a plurality of robotic cleaners 1, a navigation system 50 and two charging stations 23. The navigation system 50 is shown in the drawing as a so-called SBL acoustic positioning system, which is known to be used for underwater vessels, for example a UAV . The navigation system 50 comprises three radio transmitters 52 attached to the rearing cage 3, at a distance below the water surface 5. The rearing cage 3 is provided at the top with a floating ring 4 that floats in the water surface 5. The navigation system 50 can be used for purely position registration of the robot cleaner fish 1 or to guide the robot cleaner fish 1 along a programmed path or within a specific area in the breeding pen 3.

Two charging stations 23 are attached to the rearing cage 3 at a distance below the water surface 5. The position of the charging stations 23 is triangulated in the same way as the position of the robot cleaning fish 1. The position of the charging station 23 is automatically transferred to the navigation system 55 of the robotic cleaning fish 1. When the battery 21 of the robotic cleaning fish 1 needs to be charged, the robotic cleaning fish 1 moves to the nearest charging station 23. The charging station 23 is shown in the figure as a ball equipped with a plurality of docking stations arranged for simultaneous charging of several robotic cleaning fish 1. When the robot cleaning fish 1 is in the immediate vicinity of the charging station 23, an electromagnet will attract the robot fish 1's secondary coil 22 (see figure 1) and attach the secondary coil 22 to one of the charging station's 23 docking stations. When the battery 21 is charged, the electromagnet is deactivated and the robot cleaning fish 1 is released.

The figure shows a typical usage situation where most of the robot cleaning fish 1 are programmed to stay in a layer A in the rearing cage 3 where the occurrence of salmon lice is greatest.

It should be noted that all of the above embodiments illustrate the invention, but do not limit it, and those skilled in the art will be able to devise many alternative embodiments without departing from the scope of the appended claims. In the requirements, reference numbers in parentheses should not be seen as limiting.

The use of the verb "to comprise" and its various forms does not exclude the presence of elements or steps not mentioned in the claims. The indefinite articles "an", "ei" or "et" before an element do not exclude the presence of several such elements.

The fact that certain features are listed in mutually different dependent claims does not indicate that a combination of these features cannot be advantageously used.

Claims (10)

Patent claims 1. Apparatus (1) for neutralizing an external parasite on a fish where the apparatus (1) comprises a submersible hull or framework (10) provided with an energy system (20), a propulsion system (30) and a navigation system (50), characterized in that the device (1) further comprises means for identifying parasites and fish, a control system (90) designed to move the device (1) to a vicinity of the parasite or fish, and a tool (82) designed to neutralize the parasite. 2. Apparatus (1) according to claim 2, wherein the tool (82) comprises a suction mechanism. 3. Apparatus (1) according to any one of the preceding claims, wherein the tool (82) comprises a cutting function. 4. Apparatus (1) according to any one of the preceding claims, wherein the tool (82) comprises an electrical pulse. 5. Apparatus (1) according to any one of the preceding claims, wherein the tool (82) comprises a light pulse. 6. Apparatus (1) according to any one of the preceding claims, wherein the tool (82) comprises a sonic pulse. 7. Apparatus (1) according to any one of the preceding claims, wherein the apparatus (1) comprises a communication system (55). 8. Apparatus (1) according to any one of the preceding claims, wherein the apparatus (1) comprises means for inductive charging of a battery (21) belonging to the energy system (20). 9. Method for removing external parasites on fish in a breeding cage (3), characterized in that the method comprises the following steps: a) providing an apparatus (1) according to claim 1; b) moving the device (1) immersed in the rearing cage (3); c) activating an identification system comprising a camera, machine vision and algorithms designed to identify and target parasites; d) upon recognition of a parasite, activate the control system (90) to position the apparatus (1) in the vicinity of the identified parasite; e) neutralizing the parasite by activating the tool (82); and f) repeating steps b - e. 10. Method according to claim 9, where the method further comprises the steps: a') to continuously measure the battery's (21) current level; b') to interrupt the device's (1) search and identify parasites according to steps b) - e) of claim 9 when the battery's (21) current level reaches a lower limit value; c') to activate the device's (1) navigation system (50) to autonomously move the device (1) to a nearest charging station (23); d') to autonomously connect the device's (1) secondary coil (22) to a primary coil arranged in one of the charging station's (23) docking stations; e') charging the battery (21); f') to release the device (1) from the charging station (23) when the battery (21) is charged; and g') to allow the device (1) to resume search and identification according to steps b) - e) in claim 9.