EP3458351A1

EP3458351A1 - Watercraft for determining the location of an underwater object

Info

Publication number: EP3458351A1
Application number: EP17724481.1A
Authority: EP
Inventors: Andreas VOLLGOLD
Original assignee: Atlas Elektronik GmbH
Current assignee: Atlas Elektronik GmbH
Priority date: 2016-05-18
Filing date: 2017-04-18
Publication date: 2019-03-27
Also published as: WO2017198251A1; DE102016109105A1

Abstract

The invention relates to a watercraft for determining the location of an underwater object by means of a sonar system with an active sound transducer arrangement and a passive sound transducer arrangement, wherein underwater sound signals can be transmitted by means of the active sound transducer arrangement and received by means of the passive sound transducer arrangement, and the active sound transducer arrangement and the passive sound transducer arrangement are arranged spatially separately, wherein the active sound transducer arrangement is arranged on the body of the watercraft, and the passive sound transducer arrangement is assigned to the body of the watercraft, with the result that the watercraft can be used for determining locations in narrow and/or shallow stretches of water.

Description

Watercraft for locating an underwater object

The invention relates to a watercraft for locating an underwater object by means of a sonar system having an active sound transducer arrangement and a passive sound transducer arrangement, wherein underwater sound signals can be transmitted by means of the active sound transducer arrangement and received by means of the passive sound transducer arrangement.

[02] Sonars are usually used to locate underwater objects. The transmission and reception of underwater sound signals is not optimally practicable with conventional sonars in shallow and / or narrow waters, such as a fjord. Usually, a watercraft is used with a Bugsonar, which sends and receives with the same antenna.

[03] Alternatively, conventionally, a towed antenna is towed behind a watercraft having the active and passive parts of the sonar. Such a towed sonar consists for example of a drawn on a tow cable body, which has the active part for emitting underwater sound signals. After the drawn body followed by a strand for acoustic decoupling and then the passive part for receiving underwater sound signals, the latter is usually formed as a long tube with lined hydrophones. However, when high sensitivities and / or low frequencies are to be received, the conventional sonar technique can not be used in shallow and / or narrow waters since very long antennas are required for this purpose.

[05] In shallow and / or narrow waters, a towed antenna of up to several hundred meters in length can not be let into the water via a winch of the craft and not be pulled optimally, thus limiting the maneuverability of the craft.

[06] A rump-based sonar with a combined active and passive part or a towed sonar requires a large ship, which in the case of the towed antenna also has to have a corresponding towing force. In narrow and / or shallow waters, however, only small vessels can be used.

[07] The object of the invention is to improve the state of the art.

[08] The object is achieved by a watercraft for locating an underwater object by means of a sonar system with an active transducer arrangement and a passive transducer assembly, wherein underwater sound signals by means of the active transducer arrangement can be transmitted and received by the passive transducer assembly, and the active transducer assembly and the passive transducer assembly spatially are arranged separately, wherein the active sound transducer arrangement on

Watercraft body is arranged and the passive transducer assembly associated with the Wasserfahrzeugskorper is, so that the vessel is suitable for use in narrow and / or shallow waters.

The fact that the active transducer assembly and the passive transducer assembly of a sonar system are arranged spatially separated and thus use different antennas, the transmission and / or reception of underwater sound signals can be optimally adapted to shallow and / or narrow waters.

[10] Consequently, the craft remains manoeuvrable in narrow and / or shallow waters without affecting the transmission and / or reception of subsonic sound signals and thus the location of an underwater object.

[11] The following terminology is explained:

In a "watercraft" may be in particular a surface ship, such as a

Coaster or a tugboat, acting or an underwater vessel, such as a submarine. The watercraft is particularly suitable for driving and / or maneuvering in narrow and / or shallow waters.

[13] An "underwater object" is an object that is particularly underwater, and an underwater object may be, in particular, a natural structure, such as a rock, and / or a technical structure, such as a sunken ship or a mine , [14] An "active sound transducer arrangement" is in particular a device which converts an electrical signal into a sound signal as sound pressure, the acoustic signal being emitted in particular into the water.

In particular, a passive sound transducer arrangement receives an underwater sound signal and converts it into an electrical signal for further processing, for example hydrophones under water are used as passive sound transducers to record underwater sound. In this case, a hydrophone converts the water sound into an electrical variable corresponding to the sound pressure.

[16] "Sonar system" is understood to mean a system for locating objects in space and under water by means of transmitted and / or received sound impulses

Sound transducer arrangement and a passive

Sound transducer arrangement, which are arranged spatially separated.

[17] A "watercraft body" is in particular the hull under water of a watercraft.

[18] "Located on the vessel body" means, in particular, that the active transducer arrangement is physically connected to the vessel body. [19] "Assigned to the body of the watercraft" means, in particular, that the passive sound transducer assembly is directly or indirectly connected to the body of the craft The passive sound transducer assembly may, in particular, be attached directly to the hull of the craft or towed behind the craft, the passive one in the latter case Sound transducer assembly is connected via a tow cable with the winch on the deck of the watercraft body.

[20] A "narrow and / or shallow body of water" is in particular a body of water which is only a few kilometers wide, in particular <10km wide, preferably <3km wide, and has a depth of <1km, in particular <100m, preferably <10m ,

[21] In a further embodiment, the vessel has a weight of less than 8,000 t, in particular less than 7,000 t, preferably less than 5,000 t.

Thus, a small watercraft is provided, which can also receive low frequencies by means of a sonar system with high sensitivity and can be used to locate an underwater object in narrow and / or shallow waters.

In order to ensure optimum location of an underwater object, frequencies in the range of 2 kHz to 10 kHz, preferably from 4 kHz to 6 kHz, can be emitted by the active sound transducer arrangement and / or can be received by the passive sound transducer arrangement. Consequently, underwater objects that emit even low frequencies and / or detected by emitting low frequencies using the sonar system and can be located.

[25] In a further embodiment of the watercraft, the active sound transducer arrangement has a smaller spatial dimension and / or a smaller number of sound transducers than the passive sound transducer arrangement.

[26] Thus, the active transducer assembly can be optimally adapted to the space conditions of a small vessel and / or the emission of underwater sound signals in narrow and / or shallow waters. By a smaller dimensioning of the active

Sound transducer arrangement, the transmission power of the active transducer assembly can be optimized and adjusted. Thus, for example, too strong reflections on the shallow body of water and / or on the nearby mountains, which limit the narrow waters, can be avoided.

In that the passive transducer assembly has a larger spatial dimension than the active

Sound transducer arrangement, the sensitivity and thus the range of the received

Underwater sound signals are improved. In addition, by the longer execution of the passive

Sound transducer arrangement to receive these lower frequencies.

[28] The "spatial dimension" is in particular the space, which is determined by the three mutually orthogonal dimensions of height, width and depth Dimension is thus in particular the space requirement of the active transducer arrangement or the passive transducer arrangement.

In order to send out optimal underwater sound signals, the active transducer assembly is located at the bow of the vessel.

By arranging the active transducer assembly at the bow, in particular at the bead, a good view of the front and rear is achieved.

[31] The "bow" is in particular the front part of the vessel body.

[32] In a further embodiment of the watercraft, the active sound transducer arrangement can be moved out of and / or out of the nose of the watercraft so that the watercraft is ice-free.

Thus, in strong ice conditions, the active transducer assembly can be driven into the bow of the vessel and thus damage to the active transducer assembly can be avoided.

[34] By moving out of the active

Sound transducer arrangement and thus a greater distance of the active transducer assembly to

Watercraft body, can be sending out

Underwater sound signals and thus the view of the sonar system can be further improved. [35] For optimal reception of

Underwater sound signals to ensure the passive transducer assembly is arranged on the vessel body or configured as a towed antenna.

[36] Thus, the passive transducer assembly can be optimally adapted to the conditions of the narrow and / or shallow water.

Thus, it is possible to use even in narrow and / or shallow waters, a towed antenna, which is pulled by a small vessel. In particular, the towed antenna of the sonar system according to the invention can be made shorter, as in this trailing antenna, in contrast to conventional Schleppsonaren an active part of the sonar and a strand for acoustic decoupling not available and not necessary.

[38] A "towed antenna" is in particular a liquid- or gel-filled tubular casing in which a plurality of spaced-apart electroacoustic

Sound transducers for receiving underwater sound signals is strung. In contrast to conventional towed antennas, this towed antenna in particular has only passive sound transducers, for example hydrophones. The fact that an active sound transmitter is not included in the towed antenna, the towed antenna can be made shorter in particular. In particular, the towed antenna is towed behind the vessel via a tow cable (pull rope or pull cable). [39] In order to convert existing vessels and / or to replace the sonar system according to the invention, the active sound transducer arrangement and / or the passive sound transducer arrangement can be retrofitted.

Thus, existing watercraft can be converted with a conventional sonar on the sonar system according to the invention.

[41] In the following, the invention will be explained in more detail by means of exemplary embodiments. Show it

Figure 1 is a not to scale, schematic

Sectional view of a coaster with an active sonar system in a fjord, and

Figure 2 is a not to scale, schematic

Sectional view of a tugboat with a sonar system in a narrow inlet.

A coaster 101 with a weight of 8,000 tons travels on the water surface of a fjord 121, which is surrounded on both sides by a mountain 122.

The coaster 101 has an active

Sonar system 103, which consists of the active

Sound transducer assembly 105 and the passive transducer assembly 107 consists.

The active acoustic transducer assembly 105 is disposed on the bulbous bow 111 of the hull 109. The active one Sound transducer assembly 105 is by means of

Hydraulic cylinder 112 out of the bead bend 111 in the surrounding water of the fjord 121 out.

[45] The active transducer assembly 105 has three ceramic ring transducers with a diameter of 20cm each.

[46] Spatially separate from the active one

Sound transducer assembly 105 is the passive one

Sound transducer assembly 107 disposed in the rear of the coaster 101 on the lower hull 109. The passive acoustic transducer assembly 107 has five hydrophones and a length of Im.

By means of the active sound transducer assembly 105 underwater sound signals are emitted with a frequency of 6kHz and after reflection at the bottom of the fjord 121, the mountain 122 under water and to be underwater underwater objects (not shown) from the passive transducer assembly 107 received.

Thus, by means of the coaster 101, optimal location of underwater objects in the narrow fjord 121 can be achieved with high sensitivity without compromising the maneuverability of the coaster 101.

[49] In an alternative, it is a 6.500 tonne towed vessel 201 traveling on the water surface of a narrow inlet 221 and having a sonar system 203. The sonar system 203 has the emitting transducer assembly 205 and the receiving hydrophone assembly 207.

[50] The emitting transducer assembly 205 is located at the bow 211 of the towed ship 201 under water. The emitting transducer assembly 205 has four ceramic ring transmitters.

At the rear of the towboat 201, a winch 213 is arranged. Over the winch 213 a tow cable 215 is left in the fjord 221. On the towing cable 215 a towed antenna 217 is arranged, which has the receiving hydrophone assembly 207. The towed antenna 217 has a length of 10m.

By means of the emitting transducer arrangement 205, underwater sound signals are emitted into the narrow inlet arm 221, reflected at the seabed of the narrow inlet 221 and on underwater objects not shown, and then received by the received hydrophone arrangement 207. Thus, by means of a small towed vessel 201 with the sonar system 203, the deployment and use of a towed antenna 217 for locating underwater objects in the narrow inlet 221 is also realized.

Reference sign list

101 coaster

103 active sonar system

105 active sound transducer arrangement 107 passive sound transducer arrangement 109 ship hull

111 bulge

112 hydraulic cylinders

121 fjord

122 mountains

201 tugboat

203 sonar system

205 emitting transducer assembly 207 receiving hydrophone assembly 211 bow

213 winds

215 tow cable

217 towed antenna

221 narrow inlet

Claims

Claims:

Watercraft (101, 201) for locating a

Underwater object by means of a sonar system (103, 203) with an active sound transducer assembly (105, 205) and a passive sound transducer assembly (107, 207), wherein underwater sound signals by means of the active

Sound transducer assembly can be transmitted and received by the passive transducer assembly, characterized in that the active transducer assembly and the passive transducer assembly are arranged spatially separated, wherein the active transducer assembly on the watercraft body (109) is arranged and the passive transducer assembly is assigned to the watercraft body, so that the watercraft for Locations in narrow and / or shallow waters (121, 221) can be used.

Watercraft according to claim 1, characterized in that the watercraft has a weight of less than 8,000 tons, in particular less than 7,000 tons, preferably less than 5,000 tons.

Vessel according to one of the preceding claims, characterized in that frequencies in the range of 2kHz to 10kHz, preferably from 4kHz to 6kHz, from the active transducer arrangement can be emitted and / or from the passive transducer assembly are receivable.

Watercraft according to one of the preceding claims, characterized in that the active

Sound transducer assembly has a smaller spatial dimension and / or a smaller number of sound transducers than the passive transducer assembly. Watercraft according to one of the preceding claims, characterized in that the active

Sound transducer arrangement at the bow (111, 211) of the

Watercraft is arranged.

A watercraft according to claim 5, characterized in that the active transducer assembly out of the bow of the vessel out and / or is retractable, so that the watercraft is capable of drifting.

Watercraft according to one of the preceding claims, characterized in that the passive

Sound transducer arrangement is arranged on the watercraft body or designed as a towed antenna (217).

Sound transducer assembly and / or the passive

Sound transducer assembly can be retrofitted or are.