WO2004014724A1

WO2004014724A1 - Locating equipment in water

Info

Publication number: WO2004014724A1
Application number: PCT/DK2003/000525
Authority: WO
Inventors: Peter Poulsen; Ryan Poulsen
Original assignee: Hvalpsund Vodbinderi AS
Current assignee: Hvalpsund Vodbinderi AS
Priority date: 2002-08-07
Filing date: 2003-08-07
Publication date: 2004-02-19
Anticipated expiration: 2005-02-07
Also published as: AU2003250312A1; DK200201187A

Abstract

Facility and method for locating position of equipment used in water, where a search tool is provided on a vessel for registering a signal unit position, where this signal unit is provided in connection with a locating unit mounted on equipment used in water, and which is detached and situated on the seabed. The transmitter unit is brought to the surface by means of a float unit activated by one or more different types of activation units in the locating unit.

Description

Locating Equipment in Water

BACKGROUND OF THE INVENTION

The present invention concerns a facility for locating position of equipment used in water.

The invention furthermore concerns a locating unit for use in a facility as specified and a method for using the facility for locating the position of equipment used in water, and where a search tool mounted on a vessel is used for registering transmitted or re- fleeted signal from a signal unit that the equipment is provided with.

When fishing it may happen that a trawl gets caught in the bottom and therefore has to be released from a vessel. It may also happen that fish traps, nets or other fishing equipment has to be released or become detached from an anchorage or a vessel. Nets and traps may thus be severed from anchoring means in the shape of buoys, stakes or the like. When a fishing equipment is detached or released from its anchoring, it may drift very far due to current conditions and will often sink partly or entirely to the bottom due to the weight.

Such detached fishing equipment, commonly called ghost nets, are unwanted, since the nets will often stand in a way so that they still catch fish. Due to the weight of the bottom lines, the net will often sink to the bottom, and the net will stand up from the bottom due to the buoyancy from float devices in the float line of the net. After some time, the number caught fish will force the net to the bottom, and the fish will rot away, after which the net, due to the buoyancy from float devices will rise again and begin to catch fish. This cycle for ghost nets has resulted in that net fishing has been prohibited in some areas. Furthermore, there is a risk of hitching to other fishing equipment at a later time.

Besides the drawbacks in having detached fishing equipment located submerged under the water level and in most cases entirely or partly on the sea bottom, there will also be a considerably economic loss for a fisherman. Detached nets and trawls may often represent very large sums of money. For many years there has thus been a wish of localising and thereby salvaging detached fishing equipment.

The facility according to the present invention is thus intended for localis- ing/recovering fishing equipment in the form of net, trawl or the like, irrespectively whether these are disposed stationarily, e.g. by anchoring in sea bed or on stakes, or whether they are lost in active fishing.

It is the purpose of the present invention to indicate a facility that does not hinder nor- mal use of an associated equipment, and including a locating unit, and a method for locating the position of equipment used in water having been severed from its anchoring, and which therefore is disposed submerged under the water surface and in most cases completely or partly on the seabed.

According to the present invention, this is achieved with a facility for locating the position for equipment used in water, which facility includes a search tool provided on a vessel, and at least one locating unit including a signal unit and which is mounted directly on the equipment without changing the normal use thereof, the search tool being arranged for registering the position of the signal unit, where the locating unit includes a float unit connected with the signal unit and which via a thin line is connected with the equipment, where the locating unit furthermore includes an activation unit for releasing the float unit in order to allow the float unit to move the signal unit to the water surface, as it via the line remains connected with the equipment, and where the activation unit includes a manually actuated activation unit, a pressure actu- ated activation unit, timer actuated unit, temperature actuated unit and/or short-circuit activation unit.

The locating unit according to the invention is peculiar in that it includes a float unit, a signal unit connected with the float unit, an activation unit for releasing the float unit and a line connecting the float unit with the equipment.

The method according to the invention is peculiar in that an activation signal is provided for releasing a float unit connected with the signal unit, and which via a line is connected to the equipment, that the signal unit is moved to the water surface by the float unit as it remains connected to the equipment via the line.

In the following, facility, locating unit and method according to the present invention are described applied to locating fishing equipment. The invention, however, may find application for locating other equipment than fishing equipment, as e.g.: outboard engines

- containers or boxes shipped with freight/container ships equipment for laying cables - equipment for submarine drilling

- equipment for surveying bottom conditions of sea, lake or similar equipment as e.g. machine facilities found on deck of a vessel equipment for use in diving

Furthermore, the invention may be used for locating ships/boats that are sunk. The invention is here intended as a kind of black-box unit corresponding to that in the aircraft industry. With this application, the locating unit may be equipped with a data storage unit where the time of release, temperature conditions, depth and position are stored. This implies faster localisation of the sunken ship.

When mentioned that the search tool is provided on a vessel, this is to be understood in a broad sense. The search tool may thus be on the vessel itself at a position above or in immediate vicinity of the sea level.

The search tool may be permanently mounted on the vessel so that the vessel itself may localise and salvage the lost fishing equipment. Alternatively, the search tool may be a mobile equipment that may be taken aboard a salvaging vessel, since not all vessels are equipped with the required equipment for salvaging the lost fishing equipment.

In order that the signal unit is brought in a position where it can transmit a signal or receive signal from the search tool aboard a vessel, the signal unit is connected with a float unit moving the signal unit to the water surface and keeping it afloat. In a pre- ferred embodiment of the invention, the signal unit is incorporated in the float unit.

For activating the float unit when the fishing equipment is lost from a vessel, an activation unit is built into the locating unit, releasing the float unit when this activation unit has registered e.g. a change in pressure, a temperature difference, a broken electric connection, an exceeded time interval, or other activation parameter.

The line connecting the float unit with the equipment will preferably be a very thin synthetic line with a thickness that may be between about 1 mm and about 1/10 mm. The line may have lengths of several hundred meters. The search tool will preferably have a weight and size so that in does not hinder normal handling of fishing equipment, as e.g. nets and trawl. The search tool may thus be in a box with dimension hav- ing a volume of 1000 cm or less. For example, with a volume of about 100 cm . The line is only to withstand tensile forces from a float unit acted on by waves and cur- rents. The weight may be from about 100 g and up to 1 kg when the locating unit is used on larger equipment or when large battery capacity is required.

By releasing the float unit, the signal unit is carried with up to the water surface, where the signal unit either begins to transmits the signal for registering a search tool, or is lying and waiting on receiving/reflecting a signal transmitted from a search tool.

In order to locate the fishing equipment on which the locating unit is attached, the float unit is connected with the fishing equipment via a line. This causes that the released float unit is not carried away from the fishing equipment due to current or wind conditions, and when by locating the position of the float unit it is sure of the fishing equipment being close to or at the bottom in the area near the float unit.

The line connecting the fishing equipment with the released float unit is either connected directly to the fishing equipment or connected to the fishing equipment via the locating unit. If the line is connected to the fishing equipment via the locating unit, it is important that the locating unit is solidly secured to the fishing equipment in a way ensuring that the locating unit does not detach itself from the fishing equipment, when the float unit has been released from the locating unit and thereby causes a jerk in the locating unit when rising to the surface.

In order not to loose the fishing equipment, the line connecting the equipment and the float unit has to be of a strong and durable material, as the line is to maintain connec- tion between fishing equipment and float unit, irrespectively of action from current conditions and influence from diverse algae, plant parts, molluscs, waste and wooden parts floating in the water, and which by tangling with the line increase the tension in the line. Furthermore, when the salvaging vessel has located the float unit, the line may be used for either hauling up the fishing equipment again or for leading a gripper arrangement down to the fishing equipment.

One of the above activation units may be provided in a locating unit, or a combination of activation units, for ensuring release in a manner most suitable with regard to the actual conditions.

The advantage of having one activation unit is that the locating unit becomes cheap in production. The advantage for having a combination of plural activation unit is that the locating unit may be used for different kinds of fishing equipment, and that the different activation units can be used as back-up for each other.

In an embodiment of the invention, the locating unit is provided with a pressure actuated activating unit, where the activating unit measures the water pressure. This type of activation unit is adapted for pre-programming so that it activates the float unit at a certain water pressure level. For example, if the pressure activated activation unit is pre-programmed for activating the float unit at a water pressure of 5 bar corresponding to about 50 m, and the vessel is losing the connection to the fishing equipment, after which the fishing equipment with the locating unit sinks down towards the bottom, where the water pressure is about 7.5 bar, the pressure actuated activation unit will release the float unit when the fishing equipment is passing a water depth of 50 m.

In a second embodiment of the invention, the locating unit is provided with a timer actuated activation unit. This type of activation unit is adapted for being preprogrammed for the fishing equipment being used in a certain time interval. When the time interval is exceeded and the locating unit has not been activated, the timer actuated activation unit will release the float unit.

The timer actuated activation unit is typically activated when the fishing equipment is leaving the vessel. This activation may either be effected wirelessly, as by e.g. infrared, Bluetooth, radio waves and/or magnetic action, or may be effected manually. The timer actuated activation unit is thus to be deactivated when the fishing equipment is on the vessel again. This may be effected either wirelessly or manually.

In a third embodiment of the invention, the locating unit is provided with a short- circuit actuated activation unit that activates and releases the float unit if an electric connection is broken. E.g. a wire between a vessel and the locating unit, where in the wire there is incorporated an electric conducting connection. The activation unit registers when breakage occur on the connection and then releases the float unit. The wire may e.g. be connecting link between a series of nets or between an anchorage and a net.

The locating unit will preferably be adapted so that it is first activating the float unit by the release of the fishing equipment from the anchorage or the vessel. This may e.g. occur by the short-circuit actuated activation unit is activated only when an electric circuit established through the fishing equipment is broken. This may e.g. occur by using a relay switching on the current to the activation unit by de-activation. By such a construction, the locating unit will not consume energy in common use. This ensures that the signal unit of the locating unit and/or activation unit may be active in a longer time period after its release from the anchorage.

In the preferred embodiment of the invention, the locating unit will consist of a combination of a plurality of the said activation units.

In order that signal unit mounted on fishing equipment, which has not been lost, is not to interfere with signals from signal units connected with lost fishing equipment, means for controlling on/off condition of the locating unit have been mounted on the vessel. These means for on/off control may be mounted on the vessel in immediate vicinity of the position from where the fishing equipment is put into the water. When the fishing equipment, e.g. a fishing trawl or a fishing net, is passing an antenna with the means for on/off control, one or more members in the locating units will be activated. Also, the on/off control will provide for the activated members of the finding unit becoming deactivated when the fishing equipment is passing the antenna again.

In principle, it may be any part of the locating unit that is on/off controlled, as the locating unit cannot be activated if either the signal unit, the activation unit and/or the float unit are deactivated. In practice, it will most advantageous if the on/off control goes in and controls the activation unit so that the float unit is not released from the locating unit while the locating unit is on board the vessel.

In order to ensure that the locating unit has a long period where it is working after being activated, the locating unit includes a battery. This means that the signal unit may be powered from the battery and thereby transmit a signal for a certain period of time.

The required period of time may be up to one or more weeks with regard to the fishing equipment, as it is not always the same vessel that will search for and find the fishing equipment. Furthermore, there may be weather conditions providing that even if the vessel is equipped with a search tool it is not possible for the vessel to turn around immediately and find the lost fishing equipment. The vessel will probably only return when the weather has improved.

Alternatively, the locating unit may include a thermo-electric element, a number of solar cells, a unit for producing energy by action of the water flow, or other energy supply.

The battery used will preferably be a rechargeable battery. Hereby it becomes possible to perform a recharging when the fishing equipment is filled on board the vessel or ashore.

The signal unit may alternatively consist of a passive antenna. This passive antenna may be a passive acoustic reflector or a passive antenna of the resonance type. With signal units of this type, the facility according to the invention will be energy saving 0525

8

and simultaneously it will be possible to locate the fishing equipment even after long time stay in the water or on the seabed. This may be an advantage if a long period with bad weather is occurring, rendering impossible search immediately after the detachment of the fishing equipment.

With this embodiment of the signal unit, it will simultaneously be possible to equip a separate search vessel with a searching tool. The vessel will, will regular intervals, sail out salvage lost fishing equipment. This is an obvious possibility as the search tools may be very expensive if they are to have efficient ranges. An investment in efficient search tools may thus be outside the possibilities of the individual skipper of a fishing vessel. However, such an investment may be done in vessels being particularly adapted for search and salvaging.

As equipment is provided with at least one signal unit, it will be possible to perform a localising of the position of the signal unit, and thereby also a localising of the position of the associated fishing equipment. Thus it becomes possible to salvage the fishing equipment. By nets, trawl and the like, locating units will thus be frequently used, disposed with even spacing along the length of the net. The locating units may be provided with mutual spacing between 20 and 200 m. It is only to be ensured that a fish- ing equipment is provided with a sufficient number of locating units so that it is probable that there will always be a locating unit associated with a fishing equipment or a part of fishing equipment that is detached and sinks to the bottom.

In connection with fishing equipment, as e.g. nets or diverse net types, the locating unit may be woven into the float line instead of floats. Alternatively, or as supplement, the locating unit may be connected to the bottom line instead of a lead. The locating unit is waterproof and its constituent parts will be embedded in plastic material for avoiding beings subjected to corrosion.

As the float unit will provide for the signal unit always being at the water level, it is possible to use pings, where a ping is only emitting a signal when being triggered by the signals from another sound emitter. Such a system is thus very battery saving. Therefore, it will be possible to have a considerably longer time for searching on sal- T DK2003/000525

9

vaging lost fishing equipment. The other sound emitter may be a part of the search tool which has been provided on the vessel.

The facility according to the invention may thus be based on a signal unit provided in the locating unit and floating on the surface after activation of the float unit, and which is based on either emitting a signal or reflecting a signal.

By using the facility according to the present invention, a facility based on a signal unit designed as a passive antenna in connection with the fishing equipment will pri- marily be used in connection with stationary fishing equipment, e.g. nets. In this situation of use, the nets will be out for so long time that sufficient transmission energy in the transmitter/receiver units cannot be retained as they may be continuously activated. The signal unit placed in connection with the net in such a situation of use will therefore only be activated from the search tool on the ship when ascertained that the net has been lost.

Facilities based on the fishing equipment containing a locating unit with a signal unit transmitting signals is used in situations where fishing equipment is in use for relatively short time, as e.g. by trawl fishing. The locating unit provided on the fishing equipment may be placed on otter boards or floats associated with the trawl when this is set. The signal unit in the locating unit on the fishing equipment will immediately, when the fishing equipment has been lost, follow the released float unit to the surface and transmit signals. This is an advantage as the fishing equipment is often used on large depths where it is required rapidly to ascertain the loss of a fishing equipment.

The locating unit situated on the fishing equipment, may be recharged and may be used by being moved from one fishing equipment to another fishing equipment. Furthermore, it will be possible to arrange the signal unit in such a way that it is activated by registering current changes or by the depth set on the activation unit is changed beyond a pre-set threshold value. This is effected by using pressure sensors for switching on an electric circuit for the activation unit.

In general, it applies that the signal units are emitting a signal containing an identifica- tion code associated with the owner of the fishing equipment. This enables a vessel searching an area to locate a correct owner of a fishing equipment. This may be particularly advantageous when the facility is used by an operator having a vessel with the searching tool. Hereby it becomes possible to avoid the need for a searching tool on each single fishing vessel.

In order to avoid theft of the finding units on exposed fishing equipment, the locating unit is provided with a code that only allow deactivation of the finding unit by means of the same equipment that having activated the locating unit. An alternative may be that the signal unit transmits signals that only can be picked up by a certain searching equipment. A locating unit will thereby be without any value for persons that do not have the right searching equipment or activation equipment.

The system according to the invention may be based on kinds of communication in- eluding communication from vessel to fishing equipment and from fishing equipment to vessel via satellite. Alternatively, the communication may go from vessel to fishing equipment, and from fishing equipment directly to vessel. It is also possible to have communication from fishing equipment to vessel via satellite or directly to the vessel from the fishing equipment. Thus it is possible to arrange the system according to the invention as suitable as possible with regard to the application advantageous for a given water.

In order to ensure that the signal unit emits a signal, the signal unit is arranged for transmitting a signal, and that activation simultaneously with release of the signal unit initiates the signal transmission. This implies that the signal unit does not emit signals when the fishing equipment is on board the vessel or is under use.

In connection with the fishing equipment with at least one locating unit fitted is taken on board the vessel again, not only deactivation of the locating unit but simultaneously registration of the individual locating units occur, so that it is possible from the control unit of the locating unit to see when the locating unit is activated and deactivated. Hereby is provided a number of possibilities for registering statistical information about how rapidly fishing equipment has been salvaged and how long the individual 0525

11

locating units have been in the water.

It is also noted that different areas of application, which may be the case when fishing at sea, lake, fiord or coast, enable using a greater number of different signal units and/or activation units than those explained specifically above. A final choice of equipment will primarily depend on the depths at which is fished.

DESCRIPTION OF THE DRAWING

The invention will now be explained more closely with reference to the accompanying schematic drawings, wherein:

Fig. 1 shows a locating unit according to the invention,

Fig. 2 shows a facility according to the invention,

Fig. 3 shows a detail of the facility in Fig. 2, Fig. 4 shows a facility in operation,

Fig. 5 shows an alternative application of the location unit,

Fig. 6 shows the locating unit with released float units,

Fig. 7 shows use of the search tool,

Fig. 8 shows the locating unit mounted on an outboard engine, Fig. 9 shows the locating unit with an activated float unit, and

Fig. 10 shows the locating unit mounted between two floats.

In the Figures, same or identical parts will be designated with the same reference numerals. Therefore, no specific explanation will be given in connection with each single Figure.

In Fig. 1 is seen a locating unit 1 that include the following components: a signal unit 2, a float unit 3, a line 4, a manually actuated activation unit 5, a pressure actuated activation unit 6, a timer actuated activation unit 7, a short-circuit actuated unit 8 and a control unit 9 for the locating unit 1, and an activation unit 10 for activating the float unit 3. The signal unit 2 is incorporated in the float unit 3, which via the line 4 is connected, either directly to the locating unit 1 or directly on the fishing equipment (not shown). The combination of the different activation units 5, 6, 7, and 8 implies that the shown locating unit 1 can be used in connection with different kinds of equipment.

The manual activating 5 may be activated from the salvaging vessel (not shown), so that when the salvaging vessel (not shown) sails towards the area where the equipment has been lost, by means of an emitted signal through the water it may influence the manually actuated activation unit 5.

The pressure activation unit 6 implies that at a pre-determined pressure level, the locating unit will transmit a signal to the control unit 9 activating the float unit 3, which is thereby released and moves the signal unit 2 to the water surface.

The timer actuated activation unit 7 transmits a signal to the control unit 9 when a certain time interval has expired, and the timer actuated activation unit 7 has not been deactivated.

The short-circuit unit 8 will transmit a signal to the control unit 9 when one of the electric connections 11 is broken.

The control unit 9 furthermore collects data from different activation units 5, 6, 7, 8, so that by salvaging the fishing equipment, by transfer of these data to e.g. a computer, it may be derived which activation unit 5, 6, 7, 8 that has been triggered and when the activation unit 5, 6, 7, 8 concerned has been triggered, and the time the locating unit 1 has been in the water.

In Fig. 2 is shown a fishing equipment in the shape of a series of gill nets 14 connected with a vessel 15 with a cable 16. The gill nets 14 are set so that they are drawn at a certain distance across the seabed 31. Cables 16 are through-going at the upper edge of the gill net 14 row. On each gill net 14 is mounted a locating unit 1, and these locating units 1 are provided at the upper edge of the gill nets 14.

In Fig. 3 is shown a detail of Fig. 2 in which appears how a row of gill nets 14 are set from a vessel 15. The cable (the float line) 16 coupling the gill nets 14 together is carried past a gate 17 when setting gill nets 14 in the water. While the gill nets 14 are lying on the deck of the vessel, locating units 1 are deactivated. When setting the gill nets 14, the fitted locating units 1 will pass by an antenna 19 in which there are means for controlling on/off function in locating units 1. This means that when a locating unit passes the antenna 19, a signal is emitted, activating one or more of the components in the locating unit 1.

Fig. 4 shows how the facility is used when a net 20 (trawl) is lost. Cable 16 connecting vessel 15 with trawl 20 has been broken, and the short-circuit actuated activation unit (not shown) in the locating unit 1 transmits a signal to the control unit (not shown) of locating unit 1 that releases the float unit 3 in which is a transmitter unit 2 and which rises to the water surface 32. The transmitter unit 2 then starts transmitting signals 21 which then may be picked up by the search tool 22 on board the vessel 15.

In Fig. 5 is shown another application of a number of locating units 1 which are mounted on a number of gill nets 14, where all gill nets 14 are connected with a cable

16. If this cable 16 is broken as shown on the Figure, the locating units 1 close to the place where the cable has broken are activated. Alternatively, the buoy 23 may be fitted with a locating unit 1 which is activated when a cable 24 is broken.

In Fig. 6 is shown how a connection between a number of gill nets 14 have been broken, and where the locating units 1 have triggered and released the float units 3, where in each individual float unit 3 there is provided a signal unit 2. The float units 3 are connected with the line 4, either to the locating units 1 or to the gill nets 14.

On Fig. 7 is shown how a salvaging vessel 15 is fishing equipment 14 with a search tool 22 receiving a signal 21 from a signal unit 2 disposed in a float unit 3. Where the float unit 3 is connected with a line 4 for a gill net 14.

On Figs. 8 and 9 are shown an alternative application of a locating unit 1 which is mounted on an outboard engine 30. On Fig. 8 the outboard engine 30 is secured to the vessel 15 driving the vessel 15 in direction of arrow A. On Fig. 9, the outboard engine 30 has been lost and sunk down under the water surface 32. One of the activation units (not shown) of the locating units 1 have thereby released the float unit 3 in which there is a signal unit 2 transmitting signals 21.

In Fig. 10 is shown how a locating unit 1 is fitted between two floats 32 in connection with a float line 33. In this way it may be seen how a number of locating units 1 can be mounted along the length of a net (not shown).

The present invention is not limited to drawing and description. Other embodiments of the float unit, the different activation units, line, float unit and transmitter unit are envisaged within the frames of the present invention and defined by the attached claims.

Claims

1. Facility for locating the position of equipment used in water, the facility including a search tool provided on a vessel, and at least one locating unit including a signal unit and which is mounted directly on the equipment without changing the normal use thereof, the search tool being arranged for registering the position of the signal unit, where the locating unit includes a float unit connected with the signal unit and which via a thin line is connected with the equipment, where the locating unit furthermore includes an activation unit for releasing the float unit in order to allow the float unit to move the signal unit to the water surface, as it via the line remains connected with the equipment, and where the activation unit includes a manually actuated activation unit, a pressure actuated activation unit, timer actuated unit, temperature actuated unit and/or short-circuit activation unit.

2. Facility according to claim 1, characterised in that on the vessel there is provided means for controlling on/off condition for the locating unit.

3. Locating unit for use in a facility according to claim 1 or 2, characterised in that it includes a float unit, a signal unit connected with the float unit, an activation unit for releasing the float unit and a line connecting the float unit with the equipment.

4. Locating unit according to claim 3, characterised in that it includes a rechargeable battery.

5. Locating unit according to claim 3, characterised in that the signal unit is a passive antenna of resonance type.

6. Method for locating the position of equipment used in water by using a facility according to claim 1, as a search tool mounted on a vessel is used for registering trans- mitted or reflected signal from a signal unit that the equipment is provided with, characterised in that an activation signal is provided for releasing a float unit connected with the signal unit, and which via a line is connected to the equipment, that the signal unit is moved to the water surface by the float unit as it remains connected to the equipment via the line.

7. Method according to claim 6, characterised in that the signal unit is adapted for transmitting signal, and that the activation unit is initiating signal transmission simul- taneously with releasing the signal unit.