Ship radiation noise measuring system and double-layer cylindrical array measuring device

Abstract

The invention discloses a ship radiation noise measurement system and a double-layer cylindrical array measurement device, and the device comprises a circular bottom supporting plate, a circular top supporting plate, a supporting tube, a group of hydrophone vibrators, a distance measurement transducer, a supporting pedestal, and an electronic cabin. The two opposite ends of the supporting pipe are installed in the middle of the bottom supporting plate and the middle of the top supporting plate respectively, the two opposite ends of the hydrophone vibrator are installed on the periphery of the bottom supporting plate and the periphery of the top supporting plate respectively, and the distance measuring transducer is installed on the top supporting plate. The support base is installed below the bottom support plate, the electronic cabin is installed below the bottom support plate, the electronic cabin is surrounded by the support base, and the hydrophone vibrators are respectively connected to the electronic cabin.

Description

Technical Field

[0001] This invention relates to an electronic measuring instrument, and more particularly to a ship radiated noise measuring system and a double-layer cylindrical array measuring device, which enables the double-layer cylindrical array measuring device of this invention to function as a sound sensor in an underwater environment for receiving and measuring ship radiated noise. Background Technology

[0002] In recent years, with the continuous improvement of ship vibration reduction and noise reduction levels, the demand for measuring radiated noise from low-noise ships has also increased. Currently, most domestic and international ship noise measurement array systems are based on frequency-domain constant beamwidth beamforming technology, employing linear and volumetric arrays, exhibiting narrowband measurement characteristics and requiring a combination of high and low frequencies for measurement. Therefore, the measurement system uses a large number of hydrophones, resulting in a bulky measurement array that is difficult to deploy and retrieve, and incurs high manufacturing and maintenance costs. Furthermore, narrowband measurements can only utilize data from a portion of the hydrophones at a time, reducing the efficiency of hydrophone utilization. Summary of the Invention

[0003] One object of the present invention is to provide a ship radiated noise measurement system and a double-layer cylindrical array measurement device, wherein a portion of a set of hydrophone oscillators in the double-layer cylindrical array measurement device is located in the inner layer to form an inner layer oscillator, and another portion is located in the outer layer to form an outer layer oscillator. In this way, the hydrophone oscillators are arranged more closely, which significantly reduces the volume of the double-layer cylindrical array measurement device, facilitates deployment and retrieval, and helps to reduce the construction and maintenance costs of the double-layer cylindrical array measurement device.

[0004] One object of the present invention is to provide a ship radiated noise measurement system and a double-layer cylindrical array measurement device, wherein the hydrophone oscillators are arranged at equal intervals to provide array gain, ensure distortion-free measurement of the target signal, and facilitate a shorter measurement cycle.

[0005] According to one aspect of the present invention, a double-layer cylindrical array measuring device is provided, comprising: A circular frame; Electronic cabin; and A set of hydrophone oscillators, wherein the electronics compartment and the hydrophone oscillators are respectively mounted on the frame, and the hydrophone oscillators are respectively connected to the electronics compartment, wherein a portion of the hydrophone oscillators are located in the inner layer to form an inner layer oscillator, and another portion are located in the outer layer to form an outer layer oscillator.

[0006] According to one embodiment of the present invention, the frame includes a circular bottom support plate, a circular top support plate, and a support tube. The bottom and top of the support tube are respectively installed in the middle of the bottom support plate and the middle of the top support plate. The electronic compartment is installed on the bottom support plate, and the bottom and top of each hydrophone vibrator are respectively installed on the bottom support plate and the top support plate.

[0007] According to one embodiment of the present invention, the distance between the central axis of the outer layer oscillator and the central axis of the support tube is twice the distance between the central axis of the inner layer oscillator and the central axis of the support tube, and the distance between the central axis of the inner layer oscillator and the central axis of the support tube is twice the distance between the central axes of two adjacent hydrophone oscillators.

[0008] According to one embodiment of the present invention, the double-layer cylindrical array measuring device includes a set of protective strips, the opposite ends of each of the protective strips being respectively mounted on the bottom support plate and the top support plate, and the protective strips being located on the outer layer of the hydrophone oscillator.

[0009] According to one embodiment of the present invention, the double-layer cylindrical array measuring device includes a ranging transducer, the ranging transducer being mounted on the top support plate and connected to the electronics compartment.

[0010] According to one embodiment of the present invention, the double-layer cylindrical array measuring device includes a rudder, which is mounted on the top of the support tube and is located above the top support plate.

[0011] According to one embodiment of the present invention, the hydrophone oscillator includes a carbon fiber rod, a set of hydrophone elements, two mounting bases, and an oscillator shell. The set of hydrophone elements is arranged along the extension direction of the carbon fiber rod. Each of the mounting bases is mounted at opposite ends of the carbon fiber rod. The oscillator shell is formed on the carbon fiber rod, the hydrophone elements, and the mounting bases such that the oscillator shell encloses a portion of the carbon fiber rod, the hydrophone elements, and the mounting bases. One of the mounting bases is mounted on the bottom support plate, and the other mounting base is mounted on the top support plate.

[0012] According to one embodiment of the present invention, the bottom support plate, the top support plate, the support tube, and the protective strip are made of titanium alloy.

[0013] According to one embodiment of the present invention, the electronic compartment is cylindrical in shape, and the central axis of the electronic compartment coincides with the central axis of the support tube.

[0014] According to another aspect of the present invention, the present invention further provides a ship radiated noise measurement system, which includes two double-layer cylindrical array measurement devices, wherein each of the double-layer cylindrical measurement devices includes a circular frame, an electronics compartment, and a set of hydrophone oscillators, wherein the electronics compartment and the hydrophone oscillators are respectively mounted on the frame, and the hydrophone oscillators are respectively connected to the electronics compartment, wherein a portion of the hydrophone oscillators is located in the inner layer to form an inner layer oscillator, and another portion is located in the outer layer to form an outer layer oscillator. Attached Figure Description

[0015] Figure 1 This is a perspective view of a double-layer cylindrical array measuring device according to a preferred embodiment of the present invention.

[0016] Figure 2 This is a perspective view of the double-layer cylindrical array measuring device according to the above-described preferred embodiment of the present invention.

[0017] Figure 3 This is an exploded view of the double-layer cylindrical array measuring device according to the above-described preferred embodiment of the present invention.

[0018] Figure 4 This is an exploded view of the double-layer cylindrical array measuring device according to the above-described preferred embodiment of the present invention.

[0019] Figure 5 This is a cross-sectional schematic diagram of a hydrophone oscillator of the double-layer cylindrical array measuring device according to the above-described preferred embodiment of the present invention.

[0020] Figure 6 This is a perspective view of an electronic compartment of the double-layer cylindrical array measuring device according to the above-described preferred embodiment of the present invention.

[0021] Figure 7 This is a perspective view of the electronic compartment of the double-layer cylindrical array measuring device according to the above-described preferred embodiment of the present invention.

[0022] Figure 8 This is an exploded view of the electronic compartment of the double-layer cylindrical array measuring device according to the above-described preferred embodiment of the present invention.

[0023] Figure 9 This is an exploded schematic diagram of the electronic compartment of the double-layer cylindrical array measuring device according to the above-described preferred embodiment of the present invention.

[0024] Figure 10 This is a cross-sectional schematic diagram of the electronic compartment of the double-layer cylindrical array measuring device according to the above-described preferred embodiment of the present invention.

[0025] Figure 11 This is a perspective view of an electronic component of the electronic compartment of the double-layer cylindrical array measuring device according to the above-described preferred embodiment of the present invention.

[0026] Figure 12 This is a perspective view of the electronic components of the electronic compartment of the double-layer cylindrical array measuring device according to the above-described preferred embodiment of the present invention.

[0027] Figure 13 This is an exploded view of the electronic components of the electronic compartment of the double-layer cylindrical array measuring device according to the above-described preferred embodiment of the present invention.

[0028] Figure 14 This is an exploded view of the electronic components of the electronic compartment of the double-layer cylindrical array measuring device according to the above-described preferred embodiment of the present invention.

[0029] Figure 15 This is an exploded view of a partial structure of the electronic compartment of the double-layer cylindrical array measuring device according to the above-described preferred embodiment of the present invention.

[0030] Figure 16 This is an exploded schematic diagram from another perspective of the partial structure of the electronic compartment of the double-layer cylindrical array measuring device according to the above-described preferred embodiment of the present invention.

[0031] Figure 17 This is a schematic diagram illustrating the working principle of the electronic compartment of the double-layer cylindrical array measuring device according to the above-described preferred embodiment of the present invention. Detailed Implementation

[0032] Before detailing any embodiment of the invention, it should be understood that the invention, in its application, is not limited to the details of the construction and arrangement of the components set forth in the following description or illustrated in the following figures. The invention can have other embodiments and can be practiced or carried out in various ways. Furthermore, it should be understood that the wording and terminology used herein are for descriptive purposes and should not be considered limiting. The use of “comprising” or “having” and variations thereof is intended to cover the items set forth below and their equivalents, as well as any additional items. Unless otherwise specified or limited, the terms “installation,” “connection,” “support,” and “linkage,” and variations thereof are used broadly and cover both direct and indirect installation, connection, support, and linking. Moreover, “connection” and “linkage” are not limited to physical or mechanical connections or links.

[0033] Furthermore, firstly, in the disclosure of this invention, the terms "longitudinal," "lateral," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," and "outer," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing this invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, the above terms should not be construed as limiting the invention. Secondly, the term "a" should be understood as "at least one" or "one or more," that is, in one embodiment, the number of an element can be one, while in another embodiment, the number of the element can be multiple. The term "a" should not be construed as a limitation on the quantity.

[0034] Refer to the accompanying drawings of the specification of this invention. Figures 1 to 17 A preferred embodiment of the present invention, a double-layer cylindrical array measuring device 100, will be disclosed and described in the following description. The double-layer cylindrical array measuring device 100 includes a circular frame 10, an electronics compartment 20, and a set of hydrophone vibrators 30. The electronics compartment 20 and the hydrophone vibrators 30 are respectively mounted on the frame 10, and the hydrophone vibrators 30 are respectively connected to the electronics compartment 20. The acoustic signals collected by the hydrophone vibrators 30 are sent to the electronics compartment 20 for processing to measure the ship's radiated noise.

[0035] In the double-layer cylindrical array measuring device 100 of the present invention, a portion of the hydrophone oscillators 30 are located in the inner layer to form an inner layer oscillator 30a, and another portion are located in the outer layer to form an outer layer oscillator 30b. In this way, the hydrophone oscillators 30 are arranged more closely, which significantly reduces the volume of the double-layer cylindrical array measuring device 100, facilitates deployment and retrieval, and helps to reduce the construction and maintenance costs of the double-layer cylindrical array measuring device 100.

[0036] For example, in the appendix Figures 1 to 17In this specific example of the double-layer cylindrical array measuring device 100 of the present invention, the number of hydrophone oscillators 30 is eighteen, with six hydrophone oscillators 30 located in the inner layer to form the inner layer oscillators 30a, and twelve hydrophone oscillators 30 located in the outer layer to form the outer layer oscillators 30b. In other words, the double-layer cylindrical array measuring device 100 of the present invention includes six inner layer oscillators 30a and twelve outer layer oscillators 30b, with the outer layer oscillators 30b located outside the inner layer oscillators 30a. Thus, the hydrophone oscillators 30 are arranged more closely, significantly reducing the volume of the double-layer cylindrical array measuring device 100, facilitating deployment and retrieval, and helping to reduce the construction and maintenance costs of the double-layer cylindrical array measuring device 100.

[0037] Furthermore, the frame 10 includes a bottom support plate 11, a top support plate 12, and a support tube 13. Both the bottom support plate 11 and the top support plate 12 are circular. The bottom of the support tube 13 is installed in the middle of the bottom support plate 11, and the top of the support tube 13 is installed in the middle of the top support plate 12, so that the top support plate 12 is suspended above the bottom support plate 11 by the support tube 13. That is, the support tube 13 is vertical, and the positions of the bottom support plate 11 and the top support plate 12 correspond in the height direction. The electronics compartment 20 is installed on the bottom support plate 11 and located below it. The bottom of each of the hydrophone oscillators 30 is respectively mounted on the bottom support plate 11, and the top of each of the hydrophone oscillators 30 is respectively mounted on the top support plate 12, so that the hydrophone oscillators 30 are mounted between the bottom support plate 11 and the top support plate 12 of the frame 10.

[0038] Preferably, the bottom of the support tube 13 is rigidly mounted to the bottom support plate 11, and the top of the support tube 13 is rigidly mounted to the top support plate 12. This provides the frame 10 with a stable structure, ensuring greater sensitivity of the hydrophone oscillator 30 and facilitating the measurement of low-radiated ship noise. For example, in a specific example of the double-layer cylindrical array measuring device 100 of the present invention, the bottom of the support tube 13 can be welded to the bottom support plate 11, so that the bottom of the support tube 13 is rigidly mounted to the bottom support plate 11, and the top of the support tube 13 can be welded to the top support plate 12, so that the top of the support tube 13 is rigidly mounted to the top support plate 12.

[0039] Continue to refer to the appendix Figures 1 to 4The bottom support plate 11 includes a bottom center plate 111, a bottom outer ring plate 112, and a plurality of bottom spokes 113. The bottom outer ring plate 112 surrounds the outside of the bottom center plate 111, and the opposite ends of each bottom spoke 113 are respectively connected to the bottom center plate 111 and the bottom outer ring plate 112. Preferably, the bottom center plate 111, the bottom outer ring plate 112, and each bottom spoke 113 of the bottom support plate 11 are integrally formed. Optionally, the opposite ends of the bottom spokes 113 are respectively mounted to the bottom center plate 111 and the bottom outer ring plate 112.

[0040] Accordingly, the top support plate 12 includes a top center plate 121, a top outer ring plate 122, and a plurality of top spokes 123. The top outer ring plate 122 surrounds the outside of the top center plate 121, and the opposite ends of each of the top spokes 123 are respectively connected to the top center plate 121 and the top outer ring plate 122. Preferably, the top center plate 121, the top outer ring plate 122, and each of the top spokes 123 of the top support plate 12 are integral. Optionally, the opposite ends of the top spokes 123 are respectively mounted to the top center plate 121 and the top outer ring plate 122.

[0041] The bottom of the support tube 13 is rigidly mounted to the bottom center plate 111, and the central axis of the support tube 13 coincides with the central axis of the bottom center plate 111. The top of the support tube 13 is rigidly mounted to the top center plate 121, and the central axis of the support tube 13 coincides with the central axis of the top center plate 121. The positions of each bottom spoke 113 of the bottom support plate 11 correspond one-to-one with the positions of each top spoke 123 of the top support plate 12. The bottom of the hydrophone oscillator 30 is mounted on the bottom spoke 113 of the bottom support plate 11, and the bottom of the hydrophone oscillator 30 is mounted on the top spoke 123 of the top support plate 12.

[0042] In the appendix Figures 1 to 17In this specific example of the double-layer cylindrical array measuring device 100 of the present invention shown, the number of bottom spokes 113 of the bottom support plate 11 and the number of top spokes 123 of the top support plate 12 are both twelve. The opposite ends of each inner layer oscillator 30a are respectively installed on the odd-numbered bottom spokes 113 and the odd-numbered top spokes 123, and the opposite ends of each outer layer oscillator 30b are respectively installed on the respective bottom spokes 113 and the respective top spokes 123. That is, the opposite ends of the first inner oscillator 30a are respectively installed on the bottom spoke 113 and the top spoke 123 at the first position; the opposite ends of the second inner oscillator 30a are respectively installed on the bottom spoke 113 and the top spoke 123 at the third position; the opposite ends of the third inner oscillator 30a are respectively installed on the bottom spoke 113 and the top spoke 123 at the fifth position; the opposite ends of the fourth inner oscillator 30a are respectively installed on the bottom spoke 113 and the top spoke 123 at the seventh position; the opposite ends of the fifth inner oscillator 30a are respectively installed on the bottom spoke 113 and the top spoke 123 at the ninth position; and the opposite ends of the sixth inner oscillator 30a are respectively installed on the bottom spoke 113 and the top spoke 123 at the eleventh position.

[0043] Preferably, the distance between the central axis of the outer layer oscillator 30b and the central axis of the support tube 13 is twice the distance between the central axis of the inner layer oscillator 30a and the central axis of the support tube 13, and the distance between the central axis of the inner layer oscillator 30a and the central axis of the support tube 13 is twice the distance between the central axes of two adjacent hydrophone oscillators 30. In this way, these hydrophone oscillators 30 are arranged equidistantly to provide array gain, ensure distortion-free measurement of the target signal, and shorten the noise measurement cycle, thus achieving efficient measurement of ship radiated noise. For example, in the attached... Figures 1 to 17 In this specific example of the double-layer cylindrical array measuring device 100 of the present invention, the distance between the central axis of the outer layer oscillator 30b and the support tube 13 is 0.8m, that is, the diameter of the circle containing the central axes of the twelve outer layer oscillators 30b is 1.6m. The distance between the central axis of the inner layer oscillator 30a and the support tube 13 is 0.4m, that is, the diameter of the circle containing the central axes of the six inner layer oscillators 30a is 0.8m. The distance between the central axes of two adjacent hydrophone oscillators 30 is 0.4m.

[0044] Preferably, the top of the support tube 13 has a hook 131, through which a crane can lower the double-layer cylindrical array measuring device 100 into the water.

[0045] Reference Appendix Figure 5 The hydrophone oscillator 30 includes a carbon fiber rod 31, a set of hydrophone elements 32, two mounting bases 33, and an oscillator shell 34. The set of hydrophone elements 32 is arranged along the extending direction of the carbon fiber rod 31. A mounting base 33 is mounted on each of the opposite ends of the carbon fiber rod 31. The oscillator shell 34 is formed on the carbon fiber rod 31, the hydrophone elements 32, and the mounting bases 33, so that the oscillator shell 34 encloses a portion of the carbon fiber rod 31, the hydrophone elements 32, and the mounting bases 33. The material of the oscillator shell 34 can be polyurethane. After the carbon fiber rod 31, the hydrophone elements 32, and the mounting bases 33 are placed in a mold, polyurethane material is poured into the mold. After the polyurethane material cures, the mold is demolded to form the oscillator shell 34, thereby allowing the oscillator shell 34 to enclose a portion of the carbon fiber rod 31, the hydrophone elements 32, and the mounting bases 33.

[0046] In the appendix Figures 1 to 17 In this specific example of the double-layer cylindrical array measuring device 100 of the present invention, the number of hydrophone array elements 32 can be four. Each of the four hydrophone array elements 32 is fitted onto the carbon fiber rod 31, such that the hydrophone array elements 32 are arranged along the extending direction of the carbon fiber rod 31. The four hydrophone array elements 32 of the hydrophone vibrator 30 can be connected to the electronics compartment 20 using a single 12-core shielded watertight cable 36. (See attached diagram) Figure 5 One of the two mounting bases 33 of the hydrophone vibrator 30 has a cable hole 331 for the 12-core shielded watertight cable 36 to pass through for subsequent connection to the electronics compartment 20.

[0047] Continue to refer to the appendix Figure 3 and Figure 4 The bottom spokes 113 of the bottom support plate 11 have at least one bottom mounting groove 1131, and the top spokes 123 of the top support plate 12 have at least one top mounting groove 1231. One mounting base 33 of the hydrophone oscillator 30 is mounted in the bottom mounting groove 1131 of the bottom spokes 113, and the other mounting base 33 is mounted in the top mounting groove 1231 of the top spokes 123, so that the opposite ends of the hydrophone oscillator 30 are reliably mounted on the bottom support plate 11 and the top support plate 12.

[0048] Understandably, in order to further increase the reliability of the mounting relationship between the opposite ends of the hydrophone oscillator 30 and the bottom support plate 11 and the top support plate 12, adhesive can be used to bond the mounting base 33 and the bottom spoke 113 and to bond the mounting base 33 and the top spoke 123, or screws can be used to lock the mounting base 33 and the bottom spoke 113 and to lock the mounting base 33 and the top spoke 123.

[0049] Continue to refer to the appendix Figures 1 to 4 The double-layer cylindrical array measuring device 100 further includes a set of protective strips 40. The opposite ends of each protective strip 40 are respectively installed on the bottom support plate 11 and the top support plate 12, and the protective strips 40 are located on the outer layer of the hydrophone vibrator 30, that is, on the outside of the outer vibrator 30b. By setting the protective strips 40 between the bottom support plate 11 and the top support plate 12, and by placing the protective strips 40 on the outside of the outer vibrator 30b, not only can the structure of the frame 10 be made more stable, but direct collisions with the hydrophone vibrator 30 can also be avoided during measurement, thereby ensuring the reliability and safety of the double-layer cylindrical array measuring device 100.

[0050] It is worth mentioning that the specific manner in which the protective strip 40 is installed at its opposite ends on the bottom support plate 11 and the top support plate 12 is not limited in the double-layer cylindrical array measuring device 100 of the present invention. For example, in the attached Figures 1 to 17 In this specific example of the double-layer cylindrical array measuring device 100 of the present invention shown, screws can be used to lock the bottom of the protective strip 40 to the bottom outer ring plate 112 of the bottom support plate 11 and to lock the top of the protective strip 40 to the top outer ring plate 122 of the top support plate 12, such that the opposite ends of the protective strip 40 are respectively mounted on the bottom support plate 11 and the top support plate 12, and the protective strip 40 is located outside the outer oscillator 30b.

[0051] Preferably, the bottom support plate 11, the top support plate 12, the support tube 13 and the protective strip 40 are made of titanium alloy to meet the non-magnetic requirement of the double-layer cylindrical array measuring device 100.

[0052] Continue to refer to the appendix Figures 1 to 4The dual-layer cylindrical array measuring device 100 includes a rudder 50, which is mounted on the top of the support tube 13 and located above the top support plate 12. The rudder 50 allows for underwater attitude control of the dual-layer cylindrical array measuring device 100. Preferably, the rudder 50 is made of titanium alloy to meet the non-magnetic requirement of the dual-layer cylindrical array measuring device 100.

[0053] Continue to refer to the appendix Figures 1 to 4 The dual-layer cylindrical array measuring device 100 includes a ranging transducer (i.e., a distance sensor) 60, which is mounted on the top support plate 12 and connected to the electronics compartment 20. The ranging transducer 60 can be used to transmit and receive ranging pulses to locate objects in the surrounding environment of the dual-layer cylindrical array measuring device 100. Specifically, screws can be used to lock the ranging transducer 60 to the top spokes 123 of the top support plate 12 to mount the ranging transducer 60 to the top support plate 12.

[0054] Continue to refer to the appendix Figures 1 to 4 The dual-layer cylindrical array measuring device 100 includes a support base 70, which is mounted below the bottom support plate 11 and surrounds the electronics compartment 20. After the dual-layer cylindrical array measuring device 100 is placed in water, the support base 70 supports the entire device and prevents the electronics compartment 20 from being touched by underwater objects (e.g., reefs), thus ensuring the installation of the electronics compartment 20. Specifically, screws can be used to mount the support base 70 to the bottom support plate 11. Preferably, the support base 70 is made of titanium alloy to meet the non-magnetic requirement of the dual-layer cylindrical array measuring device 100.

[0055] Continue to refer to the appendix Figures 1 to 4 The electronic compartment 20 may be cylindrical, and its central axis coincides with the central axis of the support tube 13. Specifically, refer to the appendix... Figures 6 to 9 The electronic compartment 20 includes a compartment body 21, a compartment cover 22, a measurement transducer 23, an electronic component 24, a sacrificial anode 25, at least one watertight terminal 26, and an assembly 27.

[0056] The housing 21 is cylindrical and has a cavity 211, a housing groove 212, and a threading hole 213. The housing groove 212 is formed on the inner wall of the housing 21 and near the opening of the cavity 211. The threading hole 213 extends from the housing groove 212 to the outer surface of the housing 21, that is, the threading hole 213 communicates with the housing groove 212. Preferably, the threading hole 213 of the housing 21 extends along the width direction of the housing 21 to facilitate the subsequent threading of nylon thread. (See attached diagram) Figure 2 and Figure 4 The frame 10 includes a suspension assembly 14, which is installed below the bottom center plate 111 of the bottom support plate 11. The bottom of the cabin 21 is installed on the suspension assembly 14 to install the electronic cabin 20 at the bottom of the frame 10. Specifically, the suspension assembly 14 includes a suspension cylinder 141 and a set of suspension screws 142. The suspension cylinder 141 is fitted onto the bottom of the cabin 21 to install the cabin 21 on the suspension assembly 14, and the set of suspension screws 142 locks the suspension cylinder 141 below the bottom center plate 111 to install the suspension assembly 14 below the bottom center plate 111.

[0057] The hatch 22 has an insertion portion 221 and a hatch groove 222 surrounding the insertion portion 221. The measuring transducer 23, the electronic component 24, the sacrificial anode 25 and the watertight terminal 26 are respectively disposed on the hatch 22. The measuring transducer 23 and the watertight terminal 26 are respectively connected to the electronic component 24. The measuring transducer 23, the sacrificial anode 25 and the watertight terminal 26 are all exposed on the outer surface of the hatch 22 so that the measuring transducer 23 and the sacrificial anode 25 can be in direct contact with water. The watertight cable can be connected to the electronic compartment 20 through the watertight terminal 26.

[0058] The hatch 22 is installed on the cabin 21 such that the electronic component 24 is housed in the cabin cavity 211 of the cabin body 21 and the insertion part 221 is inserted into the cabin cavity 211 of the cabin body 21. The hatch 22 closes the opening of the cabin cavity 211 of the cabin body 21, and the position of the hatch 22 slot 22 of the hatch 22 corresponds to the position of the cabin slot 212 of the cabin body 21. The nylon wire passes through the wire hole 213 of the cabin 21 and into the cabin groove 212 of the cabin 21 and the hatch groove 222 of the hatch cover 22 to form the assembly 27. The outer side of the assembly 27 is located in the cabin groove 212 of the cabin 21, and the inner side of the assembly 27 is located in the hatch groove 222 of the hatch cover 22. In this way, the assembly 27 can reliably assemble the cabin 21 and the hatch cover 22, ensuring that the hatch cover 22 closes the opening of the cabin cavity 211 of the cabin 21, thereby forming a watertight environment in the cabin cavity 211 of the cabin 21, so that the electronic component 24 can be suspended in the watertight environment by the hatch cover 22.

[0059] Understandably, to increase the watertightness of the mounting positions of the hatch 22 and the hull 21, a sealing ring 200 can be clamped between the insert portion 221 of the hatch 22 and the hull 21, as shown in the attached figure. Figure 10 .

[0060] In the double-layer cylindrical array measuring device 100 of the present invention, the substrate of the chamber 21 and the cover 22 is copper or aluminum. In order to improve the corrosion resistance of the chamber 21 and the cover 22, the surfaces of the chamber 21 and the cover 22 are oxidized to form an oxide film. The inner surface of the cabin 21 has at least one exposed area 214, which is exposed to the bottom of the cabin cavity 211 of the cabin 21. The inner surface of the hatch 22 has at least one first exposed area 223, and the outer surface of the hatch 22 has a second exposed area 224. The electronic component 24 is mounted on the hatch 22, and the electronic component 24 is conductive through the first exposed area 223 of the hatch 22 and the substrate of the hatch 22. The sacrificial anode 25 is mounted on the hatch 22 such that the sacrificial anode 25 covers the second exposed area 224, and the sacrificial anode 25 is conductive through the second exposed area 224 and the substrate of the hatch 22. The substrate of the cover 22 is conductive. During the assembly of the electronic compartment 20, after the cover 22 suspends the electronic component 24 in the compartment cavity 211 of the compartment body 21, the electronic component 24 is conductive through the exposed area 214 of the compartment body and the substrate of the compartment body 21. Thus, the substrate of the compartment body 21 and the substrate of the cover 22 are conductive through the electronic component 24. In this way, the electronic compartment 20 can achieve cathodic protection for the compartment body 21 and the cover 22 by only installing the sacrificial anode 25 on the cover 22, which helps to simplify the structure of the electronic compartment 20. This not only helps to reduce the cost of the electronic compartment 20, but also helps to ensure the reliability of the electronic compartment 20.

[0061] It is understood that, since the sacrificial anode 25 covers the second exposed area 224 of the hatch cover 22, the second exposed area 224 of the hatch cover 22 is not in contact with water, so as to avoid affecting the corrosion resistance of the hatch cover 22.

[0062] Reference Appendix Figure 10 and Figure 15The hatch cover 22 has an upward-opening recessed groove 225. The second hatch cover exposed area 224 of the hatch cover 22 is formed at the bottom of the recessed groove 225. The shape and size of the recessed groove 225 match the shape and size of the sacrificial anode 25. After the sacrificial anode 25 is installed in the recessed groove 225 of the hatch cover 22, on the one hand, the double-layer cylindrical array measuring device 100 can prevent the sacrificial anode 25 from protruding from the hatch cover 22; on the other hand, the sacrificial anode 25 can be in communication with the substrate of the hatch cover 22 to achieve cathodic protection for the cabin body 21 and the hatch cover 22. In a specific example of the double-layer cylindrical array measuring device 100 of the present invention, a screw can be used to lock the sacrificial anode 25 to the hatch cover 22.

[0063] It is worth mentioning that the specific manner in which the exposed area 214 of the cabin 21 is formed and the first exposed area 223 and the second exposed area 224 of the hatch 22 are formed are not limited in the double-layer cylindrical array measuring device 100 of the present invention. For example, in the appendix Figures 1 to 17 In this specific example of the double-layer cylindrical array measuring device 100 of the present invention, a portion of the oxide film on the inner surface of the cabin 21 can be removed by laser engraving to form the cabin exposed area 214, a portion of the oxide film on the inner surface of the hatch 22 can be removed to form the first hatch exposed area 223, and a portion of the oxide film on the bottom of the sinking trough 225 of the hatch 22 can be removed to form the second hatch exposed area 224.

[0064] Reference Appendix Figure 16 The hatch 22 has a first cover hole 226 and at least one second cover hole 227, which are arranged adjacent to each other. The cable of the measuring transducer 23 passes through the first cover hole 226 of the hatch 22 and is connected to the electronic component 24. The threaded end of a screw passes through the second cover hole 227 of the hatch 22 and is screwed onto the measuring transducer 23 to mount the measuring transducer 23 to the hatch 22. It is understood that, to increase the watertightness of the mounting position of the hatch 22 and the measuring transducer 23, a sealing ring 200 can be clamped between the hatch 22 and the measuring transducer 23.

[0065] Continue to refer to the appendix Figure 16The hatch 22 has at least one terminal hole 228, and one end of the watertight terminal 26 is watertightly installed in the terminal hole 228 of the hatch 22 to mount the watertight terminal 26 to the hatch 22. Preferably, the hatch 22 has two terminal holes 228, and correspondingly, there are two watertight terminals 26. One end of one watertight terminal 26 is watertightly installed in one terminal hole 228 of the hatch 22, and the other end of the other watertight terminal 26 is watertightly installed in the other terminal hole 228 of the hatch 22. It is understood that the inner end of the watertight terminal 26 is connected to the electronic component 24.

[0066] Further, see attached document. Figure 10 , Figures 12 to 14 The electronic compartment 20 includes an elastic conductive part 28, which is disposed at the bottom of the electronic component 24 and is conductive to the electronic component 24. After the electronic component 24 is suspended in the compartment cavity 211 of the compartment body 21 by the compartment cover 22, the elastic conductive part 28 is pressed against the bottom of the compartment body 21 by the electronic component 24 and abuts against the exposed area 214 of the compartment body 21. In this way, the elastic conductive part 28 conductively connects the substrate of the compartment body 21 and the electronic component 24, so that the electronic component 24 is conductive to the substrate of the compartment body 21 through the exposed area 214. Thus, even if the sacrificial anode 25 is not provided in the compartment body 21, cathodic protection of the compartment body 21 can be achieved.

[0067] In the appendix Figures 1 to 17 In this specific example of the dual-layer cylindrical array measuring device 100 of the present invention, the elastic conductive part 28 is a conductive sponge that can be deformed by compression between the electronic component 24 and the housing 21. Thus, the elastic conductive part 28 not only provides conductive connection between the electronic component 24 and the substrate of the housing 21, but also provides elastic support for the electronic component 24, reducing the adverse effects of vibrations from the housing 21 on the electronic component 24. Optionally, in other alternative examples of the dual-layer cylindrical array measuring device 100 of the present invention, the elastic conductive part 28 may be a metal spring.

[0068] Further, see attached document. Figures 10 to 14 The electronic compartment 20 includes a pair of elastic support members 29. The two elastic support members 29 are disposed on opposite sides of the electronic component 24, and the elastic support members 29 abut against the inner wall of the compartment 21. When the electronic compartment 20 is affected by external force and the compartment 21 vibrates, the elastic conductive part 28 and the two elastic support members 29 can absorb the vibration to reduce the adverse effect of the vibration on the electronic component 24.

[0069] Specifically, the elastic support 29 is formed by bending a metal sheet, which includes a support section 291 and a locking section 292 extending obliquely to one end of the support section 291. Screws can be used to lock the locking section 292 to the bottom end of the electronic component 24, that is, the end of the electronic component 24 away from the housing 21, so as to set the elastic support 29 to the electronic component 24. There is a gap between the end of the support section 291 away from the locking section 292 and the electronic component 24. When the electronic component 24 is installed in the cavity 211 of the housing 21, the housing 21 presses the end of the support section 291 away from the locking section 292 toward the electronic component 24, so that the elastic support member 29 deforms. In this way, the elastic support member 29 can elastically support the electronic component 24 and the housing 21. Thus, the elastic conductive part 28 and the two elastic support members 29 cooperate with each other, which can not only prevent the electronic component 24 from shaking in the cavity 211 of the housing 21, but also absorb the vibration when the electronic housing 20 is affected by external force and the housing 21 vibrates, so as to reduce the adverse effects of vibration on the electronic component 24. Preferably, the elastic support 29 includes a bent section 293 that extends curvedly from the end of the support section 291 opposite to the locking section 292, and the bent section 293 is located inside the support section 291. This makes the end of the elastic support 29 away from the locking section 292 smoother, so as to avoid the elastic support 29 scraping against the inner wall of the cabin 21, thereby preventing damage to the oxide layer of the inner wall of the cabin 21.

[0070] Reference Appendix Figures 11 to 14The electronic component 24 includes a conductive board support 241, an adapter plate 242, and at least one main circuit board 243. The board support 241 includes a lateral extension frame 2411 and a longitudinal extension frame 2412 integrally extending downward from the middle of the lateral extension frame 2411. The adapter plate 242 is locked to the top of the lateral extension frame 2411, for example, by using screws to lock the adapter plate 242 to the top of the lateral extension frame 2411. The main circuit board 243 is locked to the side of the longitudinal extension frame 2412, for example, by using screws to lock the main circuit board 243 to the side of the longitudinal extension frame 2412. The main circuit board 243 and the adapter plate 242 are electrically connected. Screws are used to lock the lateral extension bracket 2411 to the hatch cover 22, and the lateral extension bracket 2411 and the first exposed hatch cover area 223 of the hatch cover 22 contact each other, so that the plate support 241 and the substrate of the hatch cover 22 are conductively connected. It is understood that the hatch cover 22 has a plurality of support posts 229 for locking the lateral extension bracket 2411, such that a gap can exist between the lateral extension bracket 2411 and the hatch cover 22 to accommodate the adapter plate 242 and prevent the adapter plate 242 from touching the hatch cover 22, wherein the first exposed hatch cover area 223 of the hatch cover 22 is formed on the end face of the support post 229.

[0071] Preferably, in the appendix Figures 1 to 17 In this specific example of the dual-layer cylindrical array measuring device 100 of the present invention, the electronic component 24 has two main circuit boards 243, with one main circuit board 243 locked onto each opposite side of the longitudinal extension frame 2412 of the plate support 241. The main circuit board 243 may be designed with a timing module, a data acquisition module, an interface module, a shielding module, and a transmission module. Optionally, in other examples of the dual-layer cylindrical array measuring device 100 of the present invention, the electronic component 24 may have five main circuit boards 243, which may respectively be a timing module, a data acquisition module, an interface module (interface board), a shielding module, and a transmission module (transmission board). The timekeeping module is equipped with a high-precision atomic clock to provide accurate and stable time base pulses to ensure timekeeping accuracy. The acquisition module is used to condition, convert, and acquire analog signal data. The interface module mainly provides various low-voltage power supplies and multiple signal interfaces. The screen module is used to prevent electromagnetic interference between the various modules within the electronic cabin 20. The transmission module is implemented by an FPGA chip to complete data integration and provides gigabit optical and gigabit electrical ports. It is understood that the cable of the measurement transducer 23 and the inner end of the watertight terminal 26 can be connected to the adapter board 242.

[0072] The electronic component 24 further includes an attitude sensor 244, which can be mounted on the main circuit board 243 for measuring the tilt attitude of the dual-layer cylindrical array measuring device 100. Preferably, the attitude sensor 244 can be a magnetic compass. Optionally, the attitude sensor 244 can also be mounted on the lateral extension frame 2411 or the longitudinal extension frame 2412 of the plate support 241.

[0073] The electronic component 24 further includes a conductive battery holder 245, a battery clamp 246, and a battery 247. The battery holder 245 includes a main frame plate 2451, two support arms 2452, and a support arm 2453. The two support arms 2452 are symmetrically arranged on opposite sides of the main frame plate 2451, and the support arm 2453 is disposed at the bottom of the main frame plate 2451 to form a battery cavity 2454 between the main frame plate 2451, the two support arms 2452, and the support arm 2453. In a specific example of the invention, a metal plate or alloy plate can be bent along a predetermined position to form the main frame plate 2451, the support arms 2452, and the support arm 2453. The battery 247 is housed in the battery cavity 2454 of the battery holder 245, and the battery 247 is connected to the adapter plate 242. The battery clamping plates 246 are mounted on the two support arms 2452 of the battery bracket 245 by clamping the battery 247 between the main frame plate 2451 and the battery clamping plates 246. The two support arms 2452 of the battery bracket 245 are respectively locked to the opposite sides of the longitudinal extension frame 2412 of the plate support 241, and the plate support 241 and the battery bracket 245 are electrically connected. The elastic conductive part 28 is provided on the support arm 2453 of the battery bracket 245, and the elastic conductive part 28 and the support arm 2453 are electrically connected. The locking section 292 of the elastic support member 29 is locked to the support arm 2452 of the battery bracket 245.

[0074] Reference Appendix Figure 10 , Figure 11 and Figure 15The electronic component 24 further includes a power indicator component 248, which includes a multi-color indicator light 2481 and a light guide post 2482. The multi-color indicator light 2481 is attached to the adapter plate 242 and indicates the power level of the battery 247 by displaying different colors of light. The cover 22 has a third cover hole 2210. After the light guide post 2482 is inserted into the third cover hole 2210 of the cover 22, a retaining spring 220 is used to hold the inner end of the light guide post 2482 in place, so that the light guide post 2482 is watertightly installed in the third cover hole 2210 of the cover 22. The light guide post 2482 is located directly above the multi-color indicator light 2481 and is used to guide the light emitted by the multi-color indicator light 2481 for viewing. It is possible that one of the two watertight terminals 26 of the electronic compartment 20 can be a charging terminal, so that when the battery 247 is low on power, external power can be supplied to the battery 247 through this watertight terminal 26.

[0075] The electronic compartment 20 further includes a force sensor 210, which is mounted on the cover 22 and connected to the adapter plate 242. The force sensor 210 is used to detect the water pressure at the location of the double-layer cylindrical array measuring device 100 to determine the depth of the location of the double-layer cylindrical array measuring device 100. Specifically, the cover 22 has a cover groove 22101 and a fourth cover hole 22102 extending downward from the cover groove 22101. The force sensor 210 is watertightly mounted in the cover groove 22101 of the cover 22 to prevent the force sensor 210 from protruding from the cover 22. The cable of the force sensor 210 extends through the fourth cover hole 22102 of the cover 22 and is connected to the adapter plate 242.

[0076] Preferably, the hatch 22 has a slot 22103 formed in the middle section of the cover groove 22101. The outer side of the retaining spring 220 is engaged in the slot 22103 of the hatch 22, and the inner side extends to the top surface of the force sensor 210, so that the force sensor 210 is reliably held in the cover groove 22101 of the hatch 22 by the retaining spring 220.

[0077] The electronic compartment 20 further includes a small cover 230 with multiple small cover perforations 2301. The small cover 230 is installed in the cover groove 22101 of the compartment cover 22 to conceal the force sensor 210. After the dual-layer cylindrical array measuring device 100 is submerged in water, water can reach the force sensor 210 through the small cover perforations 2301 of the small cover 230, allowing the force sensor 210 to detect the water pressure at the location of the dual-layer cylindrical array measuring device 100.

[0078] When it is necessary to measure the radiated noise of a ship, a crane can lower the double-layer cylindrical array measuring device 100 of the present invention into the water via the hook 131 of the support pipe 13. Before operation, the double-layer cylindrical array measuring device 100 connects a handheld GPS or other timing module to the timekeeping module of the electronic cabin 20. For example, the timing module can be connected to the timekeeping module of the electronic cabin 20 via a watertight connector and the watertight terminal 26. The timing module receives satellite information and transmits timing information (year, month, day, second) to the timekeeping module of the electronic cabin 20, while also transmitting 1PPS pulses to the timekeeping module. After timing is completed, the timing module disconnects, and the timekeeping module enters the timekeeping operation state. Dry-end equipment can be connected to the electronic cabin 20 via a watertight connector and the watertight terminal 26. During operation, signals such as multi-channel hydrophone array element signals and synchronous ranging signals are sent to the acquisition module through the interface module. The acquisition module contains 5 ADC 16-channel analog signal conditioning and acquisition units, which condition and convert the analog signals transmitted from the interface module to A / D before transmitting them to the transmission module. When needed, the transmission module sends a request signal (pulse signal) to the timing module. The timing module immediately sends 32 bytes of the falling edge of the request signal (including year, month, day, second and below, accurate to microseconds) to the requester, and packages it together with the signals from the bottom of the acquisition module and the signals from the attitude instrument 244, etc., and transmits it to the trunk equipment through the gigabit photoelectric port to complete the entire data acquisition and transmission function. During transmission, control commands can also be received through the photoelectric port to adjust the setting parameters of the electronic cabin 20, etc.

[0079] Appendix Figure 13 The results of data processing for a single dual-layer cylindrical array measurement device 100 in a lake environment experiment are shown. As can be seen from the figure, the array gain above 200 Hz increases with increasing frequency, and the cross-power spectrum processing array gain at 1 kHz is about 5 dB higher than the self-power spectrum processing array gain.

[0080] Appendix Figure 14The results of data processing in a lake environment experiment using two combined dual-layer cylindrical array measuring devices 100 are shown. When the two dual-layer cylindrical array measuring devices 100 are combined, a ship radiated noise measurement system is formed. By calculating the cross-correlation coefficient of the dual array joint processing and observing the cross-correlation peak value, the three noise sources on the ship (gasoline engine noise, engine room noise, and propeller noise) can be distinguished on a spatial scale. That is, the present invention further provides the ship radiated noise measurement system, which includes two dual-layer cylindrical array measuring devices 100. Through the ranging transducer 60, the two dual-layer cylindrical array measuring devices 100 can be mutually located.

[0081] Those skilled in the art should understand that the embodiments of the present invention described above and shown in the accompanying drawings are merely examples and do not limit the present invention. The objectives of the present invention have been fully and effectively achieved. The functions and structural principles of the present invention have been demonstrated and explained in the embodiments, and any modifications or variations of the embodiments of the present invention may be made without departing from the stated principles.

Claims

1. A double-layer cylindrical array measuring device, characterized in that, include: A circular frame; Electronic cabin; as well as A set of hydrophone oscillators, wherein the electronics compartment and the hydrophone oscillators are respectively mounted on the frame, and the hydrophone oscillators are respectively connected to the electronics compartment, wherein a portion of the hydrophone oscillators are located in the inner layer to form an inner layer oscillator, and another portion are located in the outer layer to form an outer layer oscillator.

2. The double-layer cylindrical array measuring device according to claim 1, wherein the frame comprises a circular bottom support plate, a circular top support plate, and a support tube, the bottom and top of the support tube being respectively installed in the middle of the bottom support plate and the middle of the top support plate, the electronics compartment being installed on the bottom support plate, and the bottom and top of each of the hydrophone oscillators being respectively installed on the bottom support plate and the top support plate; or, The distance between the central axis of the outer layer oscillator and the central axis of the support tube is twice the distance between the central axis of the inner layer oscillator and the central axis of the support tube; the distance between the central axis of the inner layer oscillator and the central axis of the support tube is twice the distance between the central axes of two adjacent hydrophone oscillators; or, The double-layer cylindrical array measuring device includes a set of protective strips, with each protective strip having its opposite ends mounted on the bottom support plate and the top support plate, respectively, and the protective strips located on the outer layer of the hydrophone oscillator; or, The dual-layer cylindrical array measuring device includes a ranging transducer, which is mounted on the top support plate and connected to the electronics compartment.

3. The double-layer cylindrical array measuring device according to claim 2, wherein the double-layer cylindrical array measuring device includes a rudder, the rudder is mounted on the top of the support tube, and the rudder is located above the top support plate.

4. The double-layer cylindrical array measuring device according to claim 2, wherein the hydrophone oscillator comprises a carbon fiber rod, a set of hydrophone array elements, two mounting bases, and an oscillator shell, the set of hydrophone array elements are arranged along the extending direction of the carbon fiber rod, and a mounting base is respectively mounted at each of the opposite ends of the carbon fiber rod, the oscillator shell is formed on the carbon fiber rod, the hydrophone array elements, and the mounting base, such that the oscillator shell encloses a portion of the carbon fiber rod, the hydrophone array elements, and the mounting base, wherein one of the mounting bases is mounted on the bottom support plate, and the other mounting base is mounted on the top support plate.

5. The double-layer cylindrical array measuring device according to claim 2, wherein the shape of the electronic compartment is cylindrical, and the central axis of the electronic compartment coincides with the central axis of the support tube.

6. A ship radiated noise measurement system, characterized in that, It includes two spaced-apart double-layer cylindrical array measuring devices, wherein each of the double-layer cylindrical array measuring devices comprises: A circular frame, wherein the frame includes a bottom support plate, a top support plate, a support tube, and a suspension assembly, wherein the bottom support plate and the top support plate are both circular, the bottom of the support tube is installed in the middle of the bottom support plate, the top of the support tube is installed in the middle of the top support plate, and the suspension assembly is installed below the bottom support plate. A set of hydrophone oscillators, wherein the bottoms of the hydrophone oscillators are respectively mounted on the bottom support plate, the tops of the hydrophone oscillators are respectively mounted on the top support plate, and the hydrophone oscillators are respectively mounted on the frame, wherein a portion of the hydrophone oscillators are located in the inner layer to form an inner layer oscillator, and another portion are located in the outer layer to form an outer layer oscillator; An electronics compartment, wherein the electronics compartment is mounted on the suspension assembly, and the hydrophone oscillators are respectively connected to the electronics compartment.

7. The ship radiated noise measurement system according to claim 6, wherein the electronics compartment includes a hull, a cover, a measuring transducer, electronic components, a sacrificial anode, watertight terminals, and fittings; the hull has a cavity, a hull groove, and a wiring hole; the hull groove is formed on the inner wall of the hull and near the opening of the cavity; the wiring hole extends from the hull groove to the outer surface of the hull; the hull is mounted on the suspension assembly; the cover has an insertion portion and a cover groove surrounding the insertion portion; the measuring transducer, the electronic components, the sacrificial anode, and the watertight terminals are respectively disposed on the cover. The measuring transducer and the watertight terminal are respectively connected to the electronic component, and the measuring transducer, the sacrificial anode and the watertight terminal are all exposed on the outer surface of the cover. The cover is installed in the cabin such that the electronic component is housed in the cabin cavity of the cabin and the insertion part is inserted into the cabin cavity. The cover closes the opening of the cabin cavity of the cabin. The position of the cover groove of the cover corresponds to the position of the cabin groove of the cabin. The nylon wire is formed after passing through the wire hole of the cabin into the cabin groove of the cabin and the cover groove of the cover.

8. The ship radiated noise measurement system according to claim 7, wherein the inner surface of the hull has a hull exposed area that exposes the bottom of the hull cavity, the inner surface of the hatch cover has a first hatch cover exposed area, the outer surface of the hatch cover has a second hatch cover exposed area, the electronic component is mounted on the hatch cover and is conductive through the first hatch cover exposed area and the substrate of the hatch cover, the sacrificial anode is mounted on the hatch cover such that the sacrificial anode covers the second hatch cover exposed area, and the sacrificial anode is conductive through the second hatch cover exposed area and the substrate of the hatch cover, and the electronic component is conductive through the hull exposed area and the substrate of the hull.

9. The ship radiated noise measurement system according to claim 8, wherein the electronics compartment further includes an elastic conductive part disposed at the bottom of the electronic component, and the elastic conductive part and the electronic component are in communication, the elastic conductive part being pressed by the electronic component against the bottom of the compartment and abutting against the exposed area of ​​the compartment, such that the elastic conductive part is conductively connected to the substrate of the compartment and the electronic component.

10. The ship radiated noise measurement system of claim 8, wherein the electronics compartment further comprises a mechanical sensor mounted on the hatch and connected to the electronic components.

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