NO346573B1 - Autonomous cleaning vessel, method and system for cleaning of an aquatic organism containing structure - Google Patents

Autonomous cleaning vessel, method and system for cleaning of an aquatic organism containing structure Download PDF

Info

Publication number
NO346573B1
NO346573B1 NO20200782A NO20200782A NO346573B1 NO 346573 B1 NO346573 B1 NO 346573B1 NO 20200782 A NO20200782 A NO 20200782A NO 20200782 A NO20200782 A NO 20200782A NO 346573 B1 NO346573 B1 NO 346573B1
Authority
NO
Norway
Prior art keywords
vessel
cleaning
orientation
movement
route
Prior art date
Application number
NO20200782A
Other languages
Norwegian (no)
Other versions
NO20200782A1 (en
Inventor
Mikkel Pedersen
Rune Andre Hansen
Original Assignee
Probotic As
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
Application filed by Probotic As filed Critical Probotic As
Priority to NO20200782A priority Critical patent/NO346573B1/en
Publication of NO20200782A1 publication Critical patent/NO20200782A1/en
Priority to PCT/EP2021/067313 priority patent/WO2022002746A1/en
Priority to EP21735692.2A priority patent/EP4175468A1/en
Publication of NO346573B1 publication Critical patent/NO346573B1/en

Links

Classifications

    • AHUMAN NECESSITIES
    • A01AGRICULTURE; FORESTRY; ANIMAL HUSBANDRY; HUNTING; TRAPPING; FISHING
    • A01KANIMAL HUSBANDRY; AVICULTURE; APICULTURE; PISCICULTURE; FISHING; REARING OR BREEDING ANIMALS, NOT OTHERWISE PROVIDED FOR; NEW BREEDS OF ANIMALS
    • A01K63/00Receptacles for live fish, e.g. aquaria; Terraria
    • A01K63/10Cleaning bottoms or walls of ponds or receptacles
    • AHUMAN NECESSITIES
    • A01AGRICULTURE; FORESTRY; ANIMAL HUSBANDRY; HUNTING; TRAPPING; FISHING
    • A01KANIMAL HUSBANDRY; AVICULTURE; APICULTURE; PISCICULTURE; FISHING; REARING OR BREEDING ANIMALS, NOT OTHERWISE PROVIDED FOR; NEW BREEDS OF ANIMALS
    • A01K63/00Receptacles for live fish, e.g. aquaria; Terraria
    • BPERFORMING OPERATIONS; TRANSPORTING
    • B08CLEANING
    • B08BCLEANING IN GENERAL; PREVENTION OF FOULING IN GENERAL
    • B08B3/00Cleaning by methods involving the use or presence of liquid or steam
    • BPERFORMING OPERATIONS; TRANSPORTING
    • B63SHIPS OR OTHER WATERBORNE VESSELS; RELATED EQUIPMENT
    • B63GOFFENSIVE OR DEFENSIVE ARRANGEMENTS ON VESSELS; MINE-LAYING; MINE-SWEEPING; SUBMARINES; AIRCRAFT CARRIERS
    • B63G8/00Underwater vessels, e.g. submarines; Equipment specially adapted therefor
    • B63G8/001Underwater vessels adapted for special purposes, e.g. unmanned underwater vessels; Equipment specially adapted therefor, e.g. docking stations
    • BPERFORMING OPERATIONS; TRANSPORTING
    • B63SHIPS OR OTHER WATERBORNE VESSELS; RELATED EQUIPMENT
    • B63GOFFENSIVE OR DEFENSIVE ARRANGEMENTS ON VESSELS; MINE-LAYING; MINE-SWEEPING; SUBMARINES; AIRCRAFT CARRIERS
    • B63G8/00Underwater vessels, e.g. submarines; Equipment specially adapted therefor
    • B63G8/001Underwater vessels adapted for special purposes, e.g. unmanned underwater vessels; Equipment specially adapted therefor, e.g. docking stations
    • B63G2008/002Underwater vessels adapted for special purposes, e.g. unmanned underwater vessels; Equipment specially adapted therefor, e.g. docking stations unmanned
    • B63G2008/004Underwater vessels adapted for special purposes, e.g. unmanned underwater vessels; Equipment specially adapted therefor, e.g. docking stations unmanned autonomously operating
    • YGENERAL 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
    • Y02TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
    • Y02ATECHNOLOGIES FOR ADAPTATION TO CLIMATE CHANGE
    • Y02A40/00Adaptation technologies in agriculture, forestry, livestock or agroalimentary production
    • Y02A40/80Adaptation technologies in agriculture, forestry, livestock or agroalimentary production in fisheries management
    • Y02A40/81Aquaculture, e.g. of fish

Landscapes

  • Life Sciences & Earth Sciences (AREA)
  • Environmental Sciences (AREA)
  • Engineering & Computer Science (AREA)
  • Mechanical Engineering (AREA)
  • Marine Sciences & Fisheries (AREA)
  • Animal Husbandry (AREA)
  • Biodiversity & Conservation Biology (AREA)
  • Aviation & Aerospace Engineering (AREA)
  • Control Of Position, Course, Altitude, Or Attitude Of Moving Bodies (AREA)
  • Farming Of Fish And Shellfish (AREA)

Description

FIELD OF THE INVENTION
The present invention relates to an autonomous cleaning vessel for cleaning of an aquatic organism containing structure of an aquatic organism breeding farm. The present invention also relates to a system for cleaning of an aquatic organism containing structure of an aquatic organism breeding farm. The present invention also relates to a method for cleaning of an aquatic organism containing structure of an aquatic organism breeding farm.
BACKGROUND OF THE INVENTION
Fish and other aquatic organisms may be farmed in so-called fish farms. A fish farm typically comprises a floating element (typically one or more air-filled plastic rings) and a net suspended below the floating element. Several such floating elements and nets are typically assembled into one structure. Sea currents are causing fresh water to be supplied to the fish via openings in the net.
Over time, marine fouling will reduce the waterflow through the net. Marine fouling will also increase the weight on the net, which may damage the net. Some types of marine fouling (algae) may impact the fish health negatively. Consequently, the net must be cleaned periodically to remove marine fouling. In prior art, there are many examples of cleaning systems for cleaning nets of fish farms.
Land-based fish-farms comprises tanks filled with water, in which fish or other aquatic organisms are bred. Fresh water is here supplied to the tank, or the water are circulated via a cleaning system. Such cleaning systems are referred to as recirculating aquaculture systems (RAS). Also here, marine fouling will form on the inside of the tank.
Some cleaning systems focus on cleaning efficiency, where a ROV with powerful jet nozzles and powerful rotating disks with jet nozzles are used to clean the net efficiently over a relatively short period of time. With this type of cleaning system, the net must be cleaned every third or fourth week. Even though effective, such powerful jet nozzles and powerful rotating brushes will increase the risk of damaging the net, which again may cause evacuation of fish from the net.
NO 343736 describes a cleaning system where a vessel is cleaning the net gently, but frequently. The cleaning system is installed on the fish farm, and is cleaning the net typically 1 – 2 times per 24 hours.
Some of the cleaning systems have cleaning vessels that are remotely controlled by means of a handheld mobile console or from a control station. The ROV here comprises different types of sensors for helping the operator of the ROV. In WO2019134055 it is described a camera equipped with compass, depth and temperature sensors. Other cleaning vessels are autonomous. In NO 20161949 one such autonomous vessel is described as a free-swimming, autonomous cleaning and inspection robot, which are using a hydro-acoustic positioning system, a compass, a gyro, a depth sensor, a temperature sensor, oxygen sensor, turbidity sensor, cameras with machine vision etc.
EP 3606338 describes a device, method and system for a cleaning device for subsea cleaning operations wherein the cleaning device comprising a frame, a first set of thrusters, a second set of thrusters, and a nose cleaning assembly arranged in a nozzle arranged in one or more of the most periphery parts of the cleaning device providing cleaning accessibility to difficult to access areas. A hydro-acoustic system is used for navigation purposes.
EP 2743173 relates to a submergible cleaning system for cleaning an underwater hull surface of a vessel while the vessel is afloat. The cleaning system comprises: a housing comprising a top face and side faces having edges and an open bottom face, the edges and bottom face being arranged opposite the hull surface, and the housing further comprises: a rotary disc having a plurality of nozzles arranged around a periphery of the rotary disc, the nozzles facing the hull surface, rolling spacing devices for providing a predetermined first gap between the rotary disc and the hull surface, a suction device fluidly connected to an outlet arranged in the housing for providing a negative pressure within the housing, a pressurising device fluidly connected with the nozzles for providing a high pressure fluid to the nozzles, whereby the nozzles are adapted for discharging fluid under high pressure against the hull surface for cleaning, wherein the housing further comprises a shroud at least partly arranged between the rotary disc and the housing.
WO 2019/093901 describes a cleaning device for cleaning a submerged surface, the cleaning device being arranged to move along a sloping operative direction of motion, and the cleaning device further comprising a first reversing device arranged to communicate with the propulsion system so that the cleaning device may switch between the first horizontal direction of motion and the second horizontal direction of motion when a cable subjects the cleaning device to a force which prevents the cleaning device from following the sloping operative direction of motion. Further, a fish cage including a plurality of cleaning devices and a method for using the cleaning device are described.
One object of the present invention is to provide a simple and robust navigation system for an autonomous cleaning vessel for cleaning the net of a fish farm. In particular, the object of the present invention is to avoid using a hydro-acoustic positioning system, as such a system is expensive and prone to faults.
Another object of the invention is to provide an alternative vessel for cleaning the net gently, but frequently.
SUMMARY OF THE INVENTION
The present invention relates to an autonomous cleaning vessel for cleaning of an aquatic organism containing structure of an aquatic organism breeding farm, where the autonomous cleaning vessel comprises:
- a body;
- a cleaning system provided at least partially outside of the body;
- a propulsion system for moving the vessel relative to the structure;
- a navigation system for controlling the propulsion system;
wherein the navigation system comprises a route planner;
wherein the propulsion system comprises a thruster;
characterized in that the navigation system further comprises:
- a orientation sensor for measuring a parameter representative of the current orientation of the vessel;
- a depth sensor for measuring a parameter representative of the current depth of the vessel;
- a central processing unit configured to control the propulsion system based on information from the orientation sensor, the depth sensor and the route planner; wherein the central processing unit is configured to control the propulsion system to keep the vessel in physical contact with the structure (3);
wherein the navigation system is configured to check physical contact between the vessel and the structure by:
- sending a control signal to the propulsion system for moving the vessel towards an assumed location of the structure;
- confirming physical contact if the movement of the vessel is less than a threshold value based on the control signal;
- not confirming physical contact if the movement of the vessel is above the threshold value based on the control signal.
In one aspect, the central processing unit configured to control the propulsion system based on information from the orientation sensor, the depth sensor and the route planner only.
In one aspect, the autonomous cleaning vessel comprises a communication system, wherein the communication system is configured to send status information from the navigation system.
In one aspect, the route planner comprises a parameter representative of a maximum cleaning depth.
In one aspect, the route planner comprises a predefined route for the vessel along the structure.
In one aspect, the route planner comprises a speed reference parameter. In one aspect, the route planner comprises a scheduler.
In one aspect, the autonomous cleaning vessel has positive buoyancy.
In one aspect, the route planner comprises a predefined route for keeping the vessel in physical contact with the structure.
In one aspect, central processing unit is configured to control the propulsion system to keep at least parts of the cleaning system in physical contact with the structure during movement of the vessel along the structure.
In one aspect, the orientation sensor comprises a magnetic compass.
In one aspect, the orientation sensor comprises a gyroscope.
In one aspect, the orientation sensor comprises a gyrocompass.
In one aspect, the orientation sensor is measuring a parameter representative of the current horizontal orientation of the body.
In one aspect, the orientation sensor is tilt-compensated.
In one aspect, a horizontal vessel position is represented as an angle between a vessel orientation and a reference orientation in the navigation system.
Alternatively, the horizontal vessel position may be expressed with other parameters, for example as a position in the horizontal plane, as polar coordinates, etc.
In one aspect, the entire vessel is located on the inside of the structure.
In one aspect, the movement is measured by the navigation system.
In one aspect, the navigation system comprises a timer for measuring time. The timer may be integrated as part of the central processing unit. The route planner may comprise an estimated time of arrival for different points along the route.
In one aspect, the central processing unit configured to control the propulsion system based on information from the orientation sensor, the depth sensor, the route planner and the timer only.
The present invention also relates to a system for cleaning of an aquatic organism containing structure of an aquatic organism breeding farm, wherein the system comprises:
- an autonomous cleaning vessel according to the above;
- a vessel station provided at sea level.
In one aspect, the autonomous cleaning vessel comprises a rechargeable battery system for powering the navigation system and the propulsion system, wherein the rechargeable battery system is charged at the vessel station.
In one aspect, the rechargeable battery system is powering the communication system.
The present invention relates to a method for cleaning of an aquatic organism containing structure of an aquatic organism breeding farm, wherein the method comprises the steps of:
a) providing a cleaning vessel comprising a body with a cleaning system provided at least partially outside of the body;
b) moving the vessel relative to, and in physical contact with, the structure; characterized in that the method further comprises the steps of:
c) measuring a parameter representative of the current orientation of the vessel; d) measuring a parameter representative of the current depth of the vessel;
e) providing a route plan for the vessel;
f) controlling the movement of the vessel by means of the route plan, the parameter representative of the current orientation of the vessel and the parameter representative of the current depth of the vessel; and controlling the movement of the vessel to keep the vessel in physical contact with the structure;
wherein the method comprises the step of:
- sending a control signal to move the vessel towards an assumed location of the structure;
- confirming physical contact if the movement of the vessel is less than a threshold value based on the control signal;
- not confirming physical contact if the movement of the vessel is above the threshold value based on the control signal.
In one aspect, the method step f) comprises:
- controlling the movement of the vessel only by means of the route plan, the parameter representative of the current orientation of the vessel and the parameter representative of the current depth of the vessel.
In one aspect, the method further comprises controlling the movement of the vessel to a maximum cleaning depth.
In one aspect, the method step e) comprises the step of:
- determining a predetermined route for the vessel along the structure (3).
In one aspect, the method step f) comprises the step of:
- controlling the movement of the vessel to keep the vessel in physical contact with the structure.
In one aspect, the method comprises the step of:
- representing a horizontal vessel position as an angle between the vessel orientation and a reference orientation.
The term “aquatic organism containing structure” is used herein for a container which can contain aquatic organisms. The structure may be a net allowing water to flow through or it may comprise a wall, for example the wall of a tank.
The term “cleaning” is used herein as a term for removing marine fouling.
The term “route” is used herein to describe a continuous path or pattern a vessel is intended to move along. A “route” can also be represented as a number of intermediate points (often referred to as “way points”) a vessel is indented to move between in a desired sequence. The route as defined by the continuous path, pattern or intermediate points is herein defined relative to a point, typically the vessel station or another point of the fish farm.
The term “navigate” (and the noun “navigation”) is used herein as a method for moving a vessel along a route in a space below sea level. To navigate along this route, parameters representative of a current location is used to calculate how the propulsion system should be operated to follow the route. It should be noted that the current location does not need to be known at all times.
DETAILED DESCRIPTION
Embodiments of the invention will now be described in detail with reference to the enclosed drawings, where:
Fig. 1 illustrates a fish farm with a vessel station and autonomous cleaning vessel; Fig. 2 illustrates the vessel schematically from a first side;
Fig. 3 illustrates the vessel schematically from a second side;
Fig. 4 is a block diagram of the cleaning vessel;
Fig. 5 illustrates orientation parameters of the navigation system;
Fig. 6 illustrates alternative orientation parameters;
Fig. 7 illustrates a land-based fish farm with an autonomous cleaning vessel.
Fig. 8 illustrates an alternative embodiment of the block diagram shown in fig. 4; Fig. 9a illustrates a fish farm with the vessel station and autonomous cleaning vessel, wherein the fish farm has a rectangular floating element;
Fig. 9b illustrates different positions for the cleaning vessel in the deeper parts of a fish farm.
It is now referred to fig. 1, where a seabased farm 1 is shown schematically, comprising a floating element 2a floating at sea level SL and where a net 3a is suspended in the seawater below the floating element 2.
In the present embodiment, the seabased farm 1 is used to breed salmon. However, the present invention may also be used for farms breeding other aquatic organisms.
The floating element 2a typically circular, and the net 3a suspended below the floating element 2a is typically cylindrical and/or conical, as shown in fig. 1.
However, both the floating element 2a and net 3a are somewhat flexible and will to some extent change shape under influence of waves, sea currents etc.
It is now referred to fig. 7. where a landbased farm 1 is shown to comprise a cylindrical tank 2b. Smolt, fish or other aquatic organisms may be bred inside the tank.
Both the net 3a and the inner surface 3b will be exposed to marine fouling, and must be cleaned. The net 3a and the inner surface 3b will hereinafter be commonly referred to as a structure 3.
In fig. 1 and fig. 7, a system 10 for cleaning of the structure3 is shown. The system 10 comprises an autonomous cleaning vessel 50 (indicated by a solid-line rectangle) and a vessel station 20 (indicated as a dashed-line rectangle) provided at sea level SL.
It is now referred to fig. 2 and fig. 3, where the vessel 50 is shown schematically.
The vessel 50 comprises a body 51, which typically will be a housing or “hull” protecting elements within the body 51 from the water outside the body 51. Fig. 3 shows the net-facing side SFS of the body 51, i.e. the side of the body 51 being faced towards the structure 3. Fig. 2 shows the opposite side of the net-facing side 3.
Visible on the outside of the body 51, the vessel 50 comprises one or more thrusters 61, which are part of a propulsion system 60. It should be noted that the thrusters 61 are here drawn very schematically as two circles each having a rotor. The location of the thrusters, the direction of the thrusters and the relative size of the thrusters are drawn schematically for illustrative purposes, and are not representative of how the propulsion system 60 may be designed to move the vessel 50 as desired.
Also visible on the outside of the body 51 is one or more brushes 81, which are part of a cleaning system 80. As shown, the brushes 81 are provided on the net-facing side of the body 51.
On the upper part of the body 51, the vessel 50 comprises a connection interface 52 for connection to a connection interface (not shown) of the vessel station 20. The connection interface 52 may be a mechanical connection interface, an electrical power connection interface and/or a communication interface.
Not visible on the outside of the body 51 (i.e. provided on the inside of the body 51), the vessel 50 comprises a navigation system 70, a communication system 90 and a rechargeable battery system 95. These systems 70, 90, 95 are indicated as dashed boxes in fig. 2.
Preferably, the rechargeable battery system 95 is used as ballast for the vessel 50 and is therefore located in the lower part of the vessel 50. The vessel 50 may further comprise a buoyancy system 53, such as a gas filled container, or bouant foam, subsea foam ( etc. However, such a gas-filled container is not essential, as an airfilled space within the body 51 itself may function as such a buoyancy system 53. Consequently, it is achieved that the vessel 50 is standing up-right in the orientation shown in fig. 2 and 3 by itself when submerged in water.
In one aspect, the autonomous cleaning vessel 50 has positive buoyancy. Hence, should there be a failure causing a stop of the propulsion system, the vessel 50 itself will float to the surface level.
It should be noted that the cleaning vessel 50 of the present invention have the same purpose as described in prior art NO 343736 where the structure 3 is cleaned gently, but frequently. Preferably, the brushes 81 of the cleaning system 80 are passive brushes, i.e. they are stationary relative to the vessel body 51. In an alternative embodiment, it is possible to provide the cleaning system 80 with active brushes, for example rotatable brushes. In such a case, the cleaning system 80 may be powered by the rechargeable battery unit 95, as shown in fig. 8. However, the cleaning system does not comprise jet nozzles, as such nozzles are not considered to be gentle.
It is well known how marine fouling is developed over time. Initially, a structure submerged in water will be covered with a conditioning film of organic polymers in relatively short time. After a while (ca 24 hours), this conditioning film allows the process of bacterial adhesion to occur, initiating the formation of a biofilm. After ca a week, the rich nutrients and ease of attachment into the biofilm allow secondary colonizers to attach themselves. Within two – three weeks, tertiary colonizers have attached. The main purpose of the gently, frequent cleaning is to remove the biofilm before secondary colonizers are allowed to attach to the structure. Hence, the present cleaning process also has the purpose of preventing severe marine fouling to develop.
According to the above, the brushes 81 must be in contact with the structure 3 for the purpose of removing early stage marine fouling from the structure and hence to prevent development of later stages of marine fouling to form on the structure 3. Hence, the propulsion system 60 is controlled to move the vessel 50 relative to, and in physical contact with, the structure 3. Hence, the brushes 81 will be moved along the structure 3. When this is performed frequently, marine fouling will not be able to grow, since the biofilm gets brushed so often that the next stages of fouling do not occur. By frequent cleaning the net is kept clean and less power is needed to remove marine fouling at early stages in development.
It is now referred to fig. 4. Here, solid lines show power flow and dashed lines show signal flow schematically.
As is shown, the rechargeable battery unit 95 supplies power to the navigation system 70, the propulsion system 60 and the communication system 90. The rechargeable battery unit 95 is also connected to the connection interface 52 to enable recharging of the unit 95 when connected to the vessel station 20.
In fig. 4, it is also shown that the navigation system 70 is sending a control signal to the propulsion system 60. The navigation system 70 comprises two sensors, an orientation sensor 71 and a depth sensor 72.
The orientation sensor 71 may comprise a magnetic compass which are sensing the orientation of the magnetic field of the earth. Alternatively, the orientation sensor 71 may comprise a gyrocompass which are sensing the rotation of the earth. Yet an alternative is to use a gyroscope which are sensing orientation relative to a reference point. Such a reference point may be the vessel station 20.
The orientation sensor 71 is configured to measure a parameter representative of the current horizontal orientation of the vessel 50. In the prototype of the present invention, the sensor LSM9DS1 from STMicroelectronics is used as orientation sensor.
The depth sensor 72 comprises a sensor for measuring a parameter representative of the depth D below sea level SL. The depth sensor 72 may for example be a pressure sensor. In the prototype of the present invention, the Bar30 sensor from BlueRobotics is used as depth sensor.
The orientation sensor 71 and the depth sensor 72 may together be referred to as a position determination system, as the relative position of the vessel can be determined from these sensors 71, 72 alone, under the assumption that the vessel is in physical contact with the structure 3 during its movement. This will be described further in detail below.
The navigation system 70 further comprises a route planner 75. The route planner comprises information about the route the vessel 50 is to move along the structure 3, in order to ensure that all desired areas of the structure 3 becomes cleaned. The route planner also comprises a schedule for how often the vessel 50 is to be used.
In the present embodiment, the vessel 50 is initially moving from the vessel station 20 and then moves a 360° lap (i.e. one entire lap around the net) back to the initial position. Then, the vessel 50 moves one level deeper, and then a further 360° lap is performed. This continues until the entire area of the structure has been covered. Then, the vessel 50 moves back to the vessel station 20 for recharging of its battery unit 95.
The navigation system 70 further comprises a central processing unit 73 configured to control the propulsion system 60 based on information from the orientation sensor 71, the depth sensor 72 and the route planner 75.
Some parameters may also be stored in either the route planner or in the central processing unit. These parameters may be:
1) structure-specific parameters, for example as diameter or circumference of structure, shape of structure, maximum cleaning depth CDmax, other geometry parameters such as transitions between a cylindrical part of the structure and a conical part of the structure etc
2) vessel-specific parameters, for example size, cleaning depth CD (fig. 3) for the brushes 81 indicating the height the vessel may clean during horizontal movement, which may be used to determine how much deeper the vessel should be moved after each 360° lap, etc
3) system specific parameters, for example position of the vessel station 20.
It should be noted that the technical function of the route planner 75 may be integrated as a part of the central processing unit 73 (as indicated in fig. 8). It should further be noted that the route planner 75 does not need to specify the exact route for the vessel. As an example, only a cleaning depth CD indicated in fig. 1 together with the time for starting each cleaning operation may be specified in the route planner. Based on this, the central processing unit 73 may contain software and/or hardware to control the propulsion system 60 to move one round until the orientation is the same as the initial orientation, and then move the vessel down, etc.
Preferably, the central processing unit 73 may control the propulsion system 60 based on information from the orientation sensor 71, the depth sensor 72 and the route planner 75 only. Consequently, complex and expensive hydro-acoustic positioning systems can be avoided.
It is now referred to fig. 5. Here, three different horizontal positions for the vessel 50 is indicated as P1, P2 and P3.
The first position P1 corresponds to the position of the vessel when the vessel is in the vessel station 20. This is used as a base reference for the orientation of the vessel 50. Here, a vessel orientation is indicated by a vector VO and a reference orientation is indicated by a vector N. When using a magnetic compass, the reference orientation may point to the magnetic north pole. When using a gyrocompass, the reference orientation may point to the axis of the rotation of earth. By definition, an angle α1 between the vessel orientation VO and the reference orientation N is set to 0°. Also when using the vessel station 20 as a sole reference point, an angle α1 is set to 0°.
When the vessel 50 is in the second position P2, it can be seen that the reference orientation N is still pointing in the same direction as in the first position. An angle α2 between the vessel orientation VO and the reference orientation N is now measured to be 45° by means of the orientation sensor 71.
When the vessel 50 is in the third position P2, it can be seen that the reference orientation N is still pointing in the same direction as in the first and second positions. An angle α3 between the vessel orientation VO and the reference orientation N is now measured to be 225° by means of the orientation sensor 71.
Hence, the horizontal position P for the vessel 50 may be expressed solely by means of the angle α in the range [0°, 360°), when assuming that the vessel 50 is in contact with the structure 3 during its movement. The vertical position is, as described above, represented by the depth D.
It is now referred to fig. 4 again. Here it is shown that the vessel 50 comprises a communication system 90. The communication system 90 is configured to send status information from the navigation system 70. In the prototype, the Waterlinked Modem M64 is used as communication system 90. The communication system 90 is preferably communicating wirelessly with the vessel station 20. Alternatively, status information is stored in the vessel 50 until the vessel 50 returns to the station 20, where status information is transferred wirelessly or via a wire to the station 20.
It should be noted that the navigation system 70 may be configured to check if there is physical contact between the vessel 50 and the structure 3. This may be needed if strong sea currents have pushed the vessel 50 away from the net, etc.
In such a situation, the navigation system 70 may send a control signal to the propulsion system 60 for moving the vessel 50 towards an assumed location of the structure 3. Physical contact is confirmed if the movement of the vessel 50 is less than a threshold value based on the control signal, i.e. that the vessel 50 is not allowed to move as far as expected based on the control signal. The threshold value will typically be set based on how far the vessel would move in water with no obstacles present. On the contrary, physical contact is not confirmed if the movement of the vessel 50 is above the threshold value based on the control signal.
There are many ways to obtain this function. If thrusters on one side is used only, movement can be measured as a change in orientation by means of the orientation sensor 71. In the same way, both thrusters may be used alternatingly, and again, movement can be measured by means of the orientation sensor 71. Change in movement may also be measured as acceleration/retardation. The sensor LSM9DS1 used as orientation sensor 71 comprises acceleration sensors which may be used for this purpose.
The navigation system 70 may further comprise a timer. This timer will typically be a part of the central processing unit 73.
It is now referred to fig. 9a. Here it is shown a fish farm with a rectangular or square floating element 3 having four sides 4a, 4b, 4c and 4d. The net (not shown in fig. 9a) is suspended vertically below the floating element and hence has a rectangular prism shape.
The system 10 can be used to clean also this type of net. The station 20 and the different positions for the vessel are shown in fig. 9a.
The first position P1 corresponds to the position of the vessel when the vessel is in the vessel station 20, similar to the first position P1 of fig. 5. The vessel station is here provided centrally on the first side 4a. Also here, this is used as a base reference for the orientation of the vessel 50, where the vessel orientation is indicated by a vector VO and a reference orientation is indicated by a vector N and where the angle α1 is set to 0°.
The vessel 50 is now moved along side 4a towards side 4b, i.e. downwardly in fig.
9a. Here, the orientation does not change until the vessel 50 meets the second side 4b. It should be noted that during this movement, the exact position of the vessel may not be known, as the orientation does not change. It should be noted that this may be acceptable for the purpose of cleaning the net – the central processing unit 73 will also here be considered to control the propulsion system 60 based on information from the orientation sensor 71, the depth sensor 72 and the route planner.
The corners between the sides may be used as reference locations or so-called way points, where the vessel is considered to be on route as long as the vessel arrives to the corners in a predetermined sequence defined by the route planner.
As mentioned above, the vessel 50 may also check if there is physical contact between the vessel 50 and the structure 3 during its straight-lined movement along the sides 4a, 4b, 4c, 4d.
When arriving to the corner between sides 4a and 4b, the vessel will detect that the movement along side 4a is obstructed, and the central processing unit 73 may control the propulsion system 60 to rotate the vessel 90°, until the correct orientation is achieved by measuring the angle α2.
In the second position P2, the vessel 50 will be in contact with either one of the first side 4a or the second side 4b or the vessel 50 will be in contact with both sides 4a, 4b.
In the third position P3, the angle α2 is 90° and the vessel 50 continues its straightline movement along the second side 4b towards the third side 4c.
It is now referred to fig. 9b. Here, three positions P10, P11, P12 are indicated, to illustrate that the orientation sensor 71 is both able to measure horizontal orientation (represented by the angle α between the horizontal vessel orientation V0 and the reference vector N as shown in fig. 5 and 9a) and vertical orientation represented by the angle β between the vertical vessel orientation and the reference vector N.
Other alternative embodiments
In the present embodiment, the vessel 50 is located on the inside of the structure 3. This is of course a requirement when the structure 3 is an inner surface 3b of a tank. It is also an advantage when the structure 3 is a net 3a, as if a failure occurs, it will be easier to find and retrieve the vessel 50 again. In addition, there are typically fewer obstacles inside the net than outside of the net. However, when the structure 3 is a net, it would be possible to utilize the principles of the present invention to move the vessel 50 along the outside of the net. It should further be noted that the principles of the present invention may be utilized with the principles of NO 343736 in that the body 51 may be separated into two sections, a first section provided on the inside of the net and a second section provided on the outside of the net, where the two sections are magnetically connected to each other.
It should be noted that there are a number of various routes the vessel may move to cover the area of the net 3. As a further example, the vessel may move vertically up and down and then move horizontally at the top and at the bottom. In such a case, a cleaning width CW should be stored in either the route planner or in the central processing unit. A spiral-shaped route is also possible.
It is now referred to fig. 6. Here, it is illustrated that the horizontal vessel position P may be expressed with other parameters, for example as a position X, Y in the horizontal plane (for example with the center of the floating element as origo), as polar coordinates r, θ, etc. However, these alternative ways of expressing the horizontal vessel position P is still achieved by using information from the orientation sensor 71 alone.

Claims (13)

1. Autonomous cleaning vessel (50) for cleaning of an aquatic organism containing structure (3) of an aquatic organism breeding farm (1), where the autonomous cleaning vessel (50) comprises:
- a body (51);
- a cleaning system (80) provided at least partially outside of the body (51);
- a propulsion system (60) for moving the vessel (50) relative to the structure (3); - a navigation system (70) for controlling the propulsion system (60);
wherein the navigation system (70) comprises a route planner (75);
wherein the propulsion system (60) comprises a thruster;
characterized in that the navigation system (70) further comprises:
- a orientation sensor (71) for measuring a parameter representative of the current orientation (V0) of the vessel (50);
- a depth sensor (72) for measuring a parameter representative of the current depth (D) of the vessel (50);
- a central processing unit (73) configured to control the propulsion system (60) based on information from the orientation sensor (71), the depth sensor (72) and the route planner (75);
wherein the central processing unit (73) is configured to control the propulsion system (60) to keep the vessel (50) in physical contact with the structure (3); wherein the navigation system (70) is configured to check physical contact between the vessel (50) and the structure (3) by:
- sending a control signal to the propulsion system (60) for moving the vessel (50) towards an assumed location of the structure (3);
- confirming physical contact if the movement of the vessel (50) is less than a threshold value based on the control signal;
- not confirming physical contact if the movement of the vessel (50) is above the threshold value based on the control signal.
2. Autonomous cleaning vessel (50) according to claim 1, wherein the route planner (75) comprises a parameter representative of a maximum cleaning depth (CDmax).
3. Autonomous cleaning vessel (50) according to claim 1 or 2, wherein the route planner (75) comprises a predefined route for the vessel (50) along the structure (3).
4. Autonomous cleaning vessel (50) according to any one of the above claims, wherein the orientation sensor (71) comprises a magnetic compass.
5. Autonomous cleaning vessel (50) according to any one of the above claims, wherein the orientation sensor (71) comprises a gyroscope.
6. Autonomous cleaning vessel (50) according to any one of the above claims, wherein a horizontal vessel position (P) is represented as an angle (α) between the vessel orientation (VO) and a reference orientation (N) in the navigation system (70).
7. Autonomous cleaning vessel (50) according to any one of the above claims, wherein the navigation system (70) comprises a timer for measuring time.
8. System (10) for cleaning of an aquatic organism containing structure (3) of an aquatic organism breeding farm (1), wherein the system (10) comprises:
- an autonomous cleaning vessel (50) according to any one of claims 1 – 7;
- a vessel station (20) provided preferably at sea level (SL).
9. System (10) according to claim 8, wherein the autonomous cleaning vessel (50) comprises a rechargeable battery system (95) for powering the navigation system (70) and the propulsion system (80), wherein the rechargeable battery system (95) is charged at the vessel station (20).
10. Method for cleaning of an aquatic organism containing structure (3) of an aquatic organism breeding farm (1), wherein the method comprises the steps of: a) providing a cleaning vessel (50) comprising a body (51) with a cleaning system (80) provided at least partially outside of the body (51);
b) moving the vessel (50) relative to the structure (3);
characterized in that the method further comprises the steps of:
c) measuring a parameter representative of the current orientation (V0) of the vessel (50);
d) measuring a parameter representative of the current depth (D) of the vessel (50); e) providing a route plan for the vessel (50);
f) controlling the movement of the vessel (50) by means of the route plan, the parameter representative of the current orientation of the vessel (50) and the parameter representative of the current depth (D) of the vessel (50); and controlling the movement of the vessel (50) to keep the vessel (50) in physical contact with the structure (3);
wherein the method comprises the step of:
- sending a control signal to move the vessel (50) towards an assumed location of the structure (3);
- confirming physical contact if the movement of the vessel (50) is less than a threshold value based on the control signal;
- not confirming physical contact if the movement of the vessel (50) is above the threshold value based on the control signal.
11. Method according to claim 10, wherein the method further comprises controlling the movement of the vessel (50) to a maximum cleaning depth
(CDmax).
12. Method according to claim 11 or 12, wherein the method step e) comprises the step of:
- determining a predetermined route for the vessel (50) along the structure (3).
13. Method according to any one of claims 10 - 12, wherein the method comprises the step of:
- representing a horizontal vessel position (P) as an angle (α) between the vessel orientation (VO) and a reference orientation (N).
NO20200782A 2020-07-03 2020-07-03 Autonomous cleaning vessel, method and system for cleaning of an aquatic organism containing structure NO346573B1 (en)

Priority Applications (3)

Application Number Priority Date Filing Date Title
NO20200782A NO346573B1 (en) 2020-07-03 2020-07-03 Autonomous cleaning vessel, method and system for cleaning of an aquatic organism containing structure
PCT/EP2021/067313 WO2022002746A1 (en) 2020-07-03 2021-06-24 Autonomous vessel, system and method for performing an operation in an aquatic organism containing structure
EP21735692.2A EP4175468A1 (en) 2020-07-03 2021-06-24 Autonomous vessel, system and method for performing an operation in an aquatic organism containing structure

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
NO20200782A NO346573B1 (en) 2020-07-03 2020-07-03 Autonomous cleaning vessel, method and system for cleaning of an aquatic organism containing structure

Publications (2)

Publication Number Publication Date
NO20200782A1 NO20200782A1 (en) 2020-07-03
NO346573B1 true NO346573B1 (en) 2022-10-17

Family

ID=71727380

Family Applications (1)

Application Number Title Priority Date Filing Date
NO20200782A NO346573B1 (en) 2020-07-03 2020-07-03 Autonomous cleaning vessel, method and system for cleaning of an aquatic organism containing structure

Country Status (3)

Country Link
EP (1) EP4175468A1 (en)
NO (1) NO346573B1 (en)
WO (1) WO2022002746A1 (en)

Families Citing this family (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
NO347849B1 (en) * 2021-09-29 2024-04-22 Watbots As Subsea assembly for adhering to and navigating across a submerged net

Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2014043411A1 (en) * 2012-09-14 2014-03-20 Raytheon Company Hull robot for autonomously detecting cleanliness of a hull
EP2743173A1 (en) * 2012-12-11 2014-06-18 C-leanship Aps A submergible cleaning system
WO2019093901A1 (en) * 2017-11-07 2019-05-16 Plastfabrikken As Cleaning device for a submerged surface
WO2019208757A1 (en) * 2018-04-26 2019-10-31 川崎重工業株式会社 Operation method in which autonomous underwater vehicle is used
EP3606338A1 (en) * 2017-04-06 2020-02-12 Abyss Aqua AS Cleaning device for subsea cleaning and a method for operating a cleaning device

Family Cites Families (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
NO336915B1 (en) * 2013-07-12 2015-11-23 Ole Molaug Eiendom As Autonomous surface cleaning device for a dive structure
US10191489B1 (en) * 2016-11-08 2019-01-29 X Development Llc Control systems for autonomous submersible structures
NO342552B1 (en) * 2016-12-08 2018-06-11 Mohn Drilling As Autonomous cleaning and inspection robot for use in a fish farm
WO2018186751A1 (en) * 2017-04-06 2018-10-11 Abyss Aqua As Cleaning device for subsea cleaning and a method for operating a cleaning device
WO2019134055A1 (en) 2018-01-05 2019-07-11 Miranda Manuel Cleaning device for aquaculture nets
US11659819B2 (en) * 2018-10-05 2023-05-30 X Development Llc Sensor positioning system

Patent Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2014043411A1 (en) * 2012-09-14 2014-03-20 Raytheon Company Hull robot for autonomously detecting cleanliness of a hull
EP2743173A1 (en) * 2012-12-11 2014-06-18 C-leanship Aps A submergible cleaning system
EP3606338A1 (en) * 2017-04-06 2020-02-12 Abyss Aqua AS Cleaning device for subsea cleaning and a method for operating a cleaning device
WO2019093901A1 (en) * 2017-11-07 2019-05-16 Plastfabrikken As Cleaning device for a submerged surface
WO2019208757A1 (en) * 2018-04-26 2019-10-31 川崎重工業株式会社 Operation method in which autonomous underwater vehicle is used

Also Published As

Publication number Publication date
EP4175468A1 (en) 2023-05-10
WO2022002746A1 (en) 2022-01-06
NO20200782A1 (en) 2020-07-03

Similar Documents

Publication Publication Date Title
US11724784B2 (en) Submersible drone devices and systems
EP3282072B1 (en) Concurrent operation of multiple robotic pool cleaners
ES2796699T3 (en) Communications between mobile robots in the aquatic environment
US8506719B2 (en) Robotic submersible cleaning system
ES2672257T3 (en) A submersible cleaning system
JPH03266794A (en) Submarine station
EP4152921B1 (en) Fish farming system
CN112478067B (en) Intelligent waterproof grass deploying and retracting probe pneumatic unmanned survey ship and survey method thereof
EP3606338B1 (en) Cleaning device for subsea cleaning and a method for operating the cleaning device
NO346573B1 (en) Autonomous cleaning vessel, method and system for cleaning of an aquatic organism containing structure
JP7506688B2 (en) Robot configured to clean the hull of a ship and control method thereof
WO2018212665A1 (en) Apparatus for rendering an external parasite on a fish harmless
CN210618409U (en) Underwater robot for cleaning ship
JP7461966B2 (en) Monitoring Module
KR20150053460A (en) Underwater cleaning robot
WO2018186751A1 (en) Cleaning device for subsea cleaning and a method for operating a cleaning device
WO2022155318A1 (en) Mobile nozzles and associated systems for cleaning pools and spas
KR102449446B1 (en) Unmanned Underwater Cleaning Robot
KR20150078178A (en) Underwater cleaning robot
WO2023227700A1 (en) Underwater cable robot
NO343379B1 (en) Cleaning device, system and method for cleaning subsea installations such as fish farm nets or cages.