Yangtze river dolphin acoustic monitoring device based on navigation mark pontoon and self-adaptive noise reduction method

Abstract

The invention discloses a Yangtze river dolphin acoustic monitoring device based on a navigation mark pontoon and a self-adaptive noise reduction method.According to the Yangtze river dolphin acoustic monitoring device based on the navigation mark pontoon, a modular aluminum profile frame with a vibration isolation function is constructed, the frame is fixed to an existing structure of the Yangtze river pontoon in a lossless mode through a damping and noise reduction assembly, and welding or drilling is not needed in the whole process; the system integrates a hydrophone, an overwater host and a solar power supply and shock absorption and noise reduction structure, and a hydrophone depth adjustable mechanism is innovatively designed. Through passive vibration reduction of the frame and active self-adaptive adjustment of the depth of the hydrophone, self-noise interference of the wharf boat is effectively isolated and eliminated, the influence of environmental noise is weakened, the signal-to-noise ratio of signal monitoring of the cowfish is remarkably increased, and the device can quickly adapt to various beacon vessel platforms in the Yangtze River. While the integrity of the wharf boat is protected, the coverage range and accuracy of Yangtze River guinea pig monitoring are remarkably improved, and therefore a high-precision and high-universality solution is provided for ecological monitoring of the Yangtze River water area.

Description

Technical Field

[0001] This invention relates to the field of finless porpoise monitoring technology, specifically to an acoustic monitoring device for Yangtze finless porpoises based on a buoy buoy and an adaptive noise reduction method. Background Technology

[0002] The Yangtze finless porpoise is a freshwater dolphin endemic to the Yangtze River. The IUCN Species Survival Commission classifies it as "critically endangered," second only to extinction in the wild, and it is a Class I protected wild animal in China. As an important indicator species of the Yangtze River ecosystem, its population size and survival status have always been a major concern. While monitoring technologies for the porpoise have made some progress, limitations still exist.

[0003] Traditional monitoring of finless porpoises primarily relies on direct observation from shore-based or ship-based facilities. Researchers use optical equipment such as telescopes to conduct long-term observations and recordings in the porpoise's habitat to obtain information on its population size, distribution, and behavior. This method has the advantage of providing direct, intuitive information and supporting detailed behavioral analysis. However, it has significant limitations. Observation activities are highly susceptible to natural conditions such as weather, lighting, and visibility, making it difficult to conduct in adverse environments such as heavy rain or dense fog. When facing the vast Yangtze River basin, the scope of manual observation is limited, making it difficult to cover the entire habitat of the porpoise, which can easily lead to missed detections and thus affect the accuracy of population size and distribution assessments.

[0004] Existing monitoring technologies based on fixed platforms (such as installing equipment on the shore or on dedicated vessels) also face challenges. To protect the Yangtze River's ecological environment and waterway safety, strict restrictions are placed on the addition of new vessels. Therefore, monitoring platforms often require structural modifications to existing floating vessels. Welding is commonly used to fix the monitoring equipment and provide stable support during these modifications, but this method causes irreversible structural damage to the existing floating vessel hull. Furthermore, floating vessels and pontoons generate mechanical vibrations, wave impacts, and motor noise during operation. These structural noises are transmitted to hydrophones through rigid connections, severely affecting acoustic signal quality and reducing the signal-to-noise ratio (SNR). Simultaneously, the frequency of finless porpoise vocalizations is closely related to river surface noise and water flow conditions, with significant differences in sound propagation characteristics across different water layers. Traditional monitoring devices are typically deployed at fixed depths, making it impossible to dynamically adjust the hydrophone position according to the real-time acoustic environment, resulting in unstable signal quality. Summary of the Invention

[0005] The technical problem to be solved by this invention is: how to solve the industry pain point of low signal-to-noise ratio in underwater acoustic signal monitoring caused by the coupling of platform mechanical vibration and underwater environmental noise in existing floating platform monitoring technology.

[0006] To solve the above-mentioned technical problems, the present invention provides the following technical solution: The acoustic monitoring device for Yangtze finless porpoises based on a buoy includes a hull, an aluminum profile frame installed at the top and stern of the hull, and a hydrophone mechanism, a surface host, and a power supply mechanism that are detachably fastened to the frame. Vibration damping and noise reduction components are provided at the connection points between the hydrophone mechanism, the surface host, the power supply mechanism and the aluminum profile frame. The surface host has a built-in noise analysis module, and the hydrophone mechanism and the power supply mechanism are both connected to the surface host. The hydrophone mechanism includes a detector bracket fixed on an aluminum profile frame, a hydrophone support rod vertically installed inside the detector bracket, and a hydrophone fixed at the bottom of the hydrophone support rod, wherein the hydrophone can be inserted into the river.

[0007] This application constructs a modular aluminum profile frame with vibration isolation function, and uses vibration damping and noise reduction components to non-destructively fix the frame to the existing structure of the Yangtze River pontoon, without any welding or drilling. The system integrates hydrophones, a surface-mounted main engine, solar power supply, and vibration damping and noise reduction structures, and innovatively designs an adjustable hydrophone depth mechanism. This invention effectively isolates and eliminates self-noise interference from the pontoon and weakens the impact of environmental noise through passive vibration damping of the frame and active adaptive adjustment of the hydrophone depth, significantly improving the signal-to-noise ratio of finless porpoise signal monitoring. It can be quickly adapted to various navigation aid vessel platforms on the Yangtze River. While protecting the integrity of the pontoon, it significantly improves the coverage and accuracy of Yangtze finless porpoise monitoring, thus providing a high-precision and highly versatile solution for ecological monitoring in the Yangtze River basin.

[0008] As a further embodiment of the present invention: the aluminum profile frame is detachably fixed to the cross-shaped bollards and low guardrails set on the top of the hull by means of clamps.

[0009] As a further embodiment of the present invention: two sets of cross-shaped bollards are provided, and the two sets of cross-shaped bollards are symmetrically fixed on both sides of the top of the hull; two sets of low guardrails are provided, and the two sets of low guardrails are provided on one side of the two sets of cross-shaped bollards, and the two sets of low guardrails are symmetrically fixed on both sides of the top of the hull.

[0010] As a further aspect of the present invention, the shock absorption and noise reduction component includes a flexible isolation pad or an elastic connector.

[0011] As a further aspect of the present invention: the power supply mechanism includes a battery box, which is connected to the hydrophone mechanism and the main watercraft, and is horizontally reinforced by an aluminum profile surrounding the battery box.

[0012] As a further aspect of the present invention: the main watercraft is located above the power supply mechanism, and the main watercraft is detachably fixed to the aluminum profile frame by clamps. The height of the main watercraft is increased by the aluminum profile, and an aluminum profile is installed on one side of the raised part as a diagonal rib.

[0013] As a further aspect of the present invention: a shipboard light assembly and a solar panel for the light assembly are installed on the top of the hull and on one side of the aluminum profile frame, wherein the solar panel for the light assembly is connected to the shipboard light assembly.

[0014] As a further aspect of the present invention, a mooring bollard is also provided at the bow position of the top of the hull.

[0015] As a further embodiment of the present invention: a solar panel bracket is detachably installed above the aluminum profile frame and above the power supply mechanism, wherein the top of the solar panel bracket is an inclined surface, and a solar panel is fixed on the inclined surface.

[0016] This invention also discloses an acoustic monitoring device for Yangtze finless porpoises based on a buoy and an adaptive noise reduction method, comprising the following steps: The floating main unit has a built-in real-time noise analysis module that can identify and quantify the self-noise of the floating vessel and the underwater environmental noise level. The hydrophone depth can be combined with the noise analysis results of the floating main unit to adaptively adjust the extension length of the hydrophone support rod, placing the hydrophone in the water layer with the least impact of environmental noise and the self-noise of the hull or at the optimal acoustic channel depth for finless porpoise signals, thus achieving active adaptive optimization of the acoustic environment. During monitoring, the power supply unit provides power to the hydrophone and the onboard host to ensure the normal operation of the device; the finless porpoise signal detected by the hydrophone is transmitted to the onboard host, and then sent back to the monitoring unit by the onboard host, thus achieving the purpose of finless porpoise detection.

[0017] Compared with the prior art, the beneficial effects of the present invention are: 1. This application utilizes non-destructive installation and hull protection, employing fasteners such as clamps and bolts, combined with an industrial aluminum profile frame, to achieve a rigid connection with the hull structure such as cross bollards and low guardrails, thus eliminating destructive processes such as welding and drilling, and maximizing the structural safety and integrity of floating vessels (especially navigation aid vessels undertaking waterway maintenance tasks). 2. This application can achieve passive isolation and active elimination of structural noise. Specifically, the flexible damping isolation design introduced in this application blocks the propagation of the floating ship's mechanical vibration to the hydrophone support rod from a physical structure perspective, attenuating the energy of the ship's self-noise to the minimum level required for monitoring, thereby effectively improving the basic signal-to-noise ratio of monitoring.

[0018] 3. This application can achieve adaptive optimization of the acoustic environment. Specifically, by using the noise analysis module built into the underwater host and the hydrophone depth-adjustable mechanism to work together, the system can intelligently select the best monitoring depth according to the real-time underwater environment, adaptively avoid strong noise areas or acoustic interference sources in the water layer, and ensure that the acquisition of finless porpoise signals is always in the optimal signal-to-noise ratio state.

[0019] 4. This application enables universal adaptability and rapid deployment. The modular aluminum profile frame design has extremely strong dimensional adaptability and structural flexibility, and can be widely adapted to different types of navigation aid vessels on the Yangtze River and other floating platforms with similar structures (cross-shaped bollards, low railings). This makes the system particularly suitable as a universal monitoring terminal, which can be quickly deployed on navigation aid vessels near water-related projects such as bridge construction, water conservancy construction, wharf expansion, and channel dredging.

[0020] 5. This application is effective and operable. The system has a stable structure, and the solar power supply can ensure long-term operation. The deployment process is simple and quick, requiring no special shipyard modification. Ordinary technicians can quickly complete the installation and commissioning on the project site, which greatly improves the response speed and operability of finless porpoise protection monitoring during the critical window of the construction period.

[0021] 6. This application can improve monitoring efficiency, overcome the limitations of manual observation, realize all-weather, wide-coverage acoustic monitoring, significantly improve the accuracy and timeliness of finless porpoise population monitoring data, and also provide strong technical support for ecological protection decision-making during the construction period of water-related projects. Attached Figure Description

[0022] Figure 1 This is a top view of the finless porpoise monitoring device according to an embodiment of the present invention; Figure 2 This is a schematic diagram of the structure of the aluminum profile frame, cross-shaped cable bollards, and low guardrail after installation according to an embodiment of the present invention; Figure 3 This is a schematic diagram of the aluminum profile structure according to an embodiment of the present invention; Figure 4 This is a schematic diagram illustrating the principle of a battery box supplying power to several devices according to an embodiment of the present invention; Figure 5 This is a schematic diagram of the battery box and the main watercraft structure according to an embodiment of the present invention; Figure 6 This is a schematic diagram of the detector fixing part according to an embodiment of the present invention; Explanation of reference numerals in the attached figures: 1. Hull; 2. Cross bollard; 3. Low guardrail; 4. Detector bracket; 5. Battery box; 6. Marine engine; 7. Solar panel bracket; 8. Hydrophone support rod; 9. Hydrophone; 10. Clamp; 11. Bolt; 12. Hex bolt; 13. Onboard lights; 14. Solar panels for lights; 15. Bollard. Detailed Implementation

[0023] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions of the embodiments of the present invention will be clearly and completely described below in conjunction with the embodiments of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0024] Reference Figure 1-6 The acoustic monitoring device for Yangtze finless porpoises based on a buoy includes a hull 1, a cross-shaped bollard 2, a low guardrail 3, a detector bracket 4, a battery box 5, a marine main engine 6, a solar panel bracket 7, a hydrophone support rod 8, a hydrophone 9, a clamp 10, a bolt 11, a hex bolt 12, a shipboard light assembly 13, a solar panel for the light assembly 14, and a bollard 15.

[0025] The monitoring device of this application is built on the existing floating hull 1 of the Yangtze River. Due to the limited space of the floating hull and the inability to damage the hull structure, the device is built using only the existing structure on the ship. The front half of the floating hull is already occupied by the existing structure, so the device is built in the relatively limited space of the rear half.

[0026] Reference Figure 1 and Figure 2 The top of the hull 1 is equipped with a frame, and aluminum profiles are used as the frame of the overall structure. The aluminum profiles are fixed to the cross-shaped cable piles 2 and the low guardrails 3 on the top of the hull 1 by clamps 10 and their wrapping structure. This fixing method does not damage the hull, and its flexibility allows the structure to be adjusted within a certain range to adapt to various scenarios and needs.

[0027] Reference Figure 1 and Figure 2 Two sets of cross-shaped bollards 2 are provided, and the two sets of cross-shaped bollards 2 are symmetrically fixed on both sides of the top of the hull 1. The two sets of cross-shaped bollards 2 are detachably connected to the frame of the top of the hull 1 through clamps 10. Two sets of low guardrails 3 are provided, and the two sets of low guardrails 3 are located on one side of the two sets of cross-shaped bollards 2. The two sets of low guardrails 3 are symmetrically fixed on both sides of the top of the hull 1. The two sets of low guardrails 3 are detachably connected to the frame of the top of the hull 1 through clamps 10.

[0028] Reference Figure 3 and Figure 6 The detector bracket 4 is detachably fixed to the aluminum profile frame by T-shaped bolts 11, and the detector bracket 4 is located on the outside of the hull 1. The hydrophone support rod 8 is slidably connected inside the detector bracket 4, and the hydrophone support rod 8 and the detector bracket 4 are fixed by hexagonal bolts 12. The hydrophone 9 is installed at the bottom of the hydrophone support rod 8, and the hydrophone 9 can be inserted into the river.

[0029] It is important to note that the aluminum profile frame, as the core support frame of the entire detection system, is designed with high flexibility in size and connection method, adaptable to common existing structures on floating vessels such as Yangtze River navigation buoys. Furthermore, high-damping flexible isolation pads or elastic connectors are embedded at the connection points between the aluminum profile frame and the cross-shaped bollard 2 and the low guardrail 3, as well as at the connection points between the detector bracket 4 and the frame. These components constitute a passive vibration isolation module, effectively cutting off the path of structural noise generated by the floating vessel's main engine, generator, and water flow impact to the hydrophone support rod through rigid connections.

[0030] Reference Figure 1 , Figure 2 , Figure 3 and Figure 5 The battery box 5 is installed on the top of the hull 1 and is fixed by the aluminum profile frame on the top of the hull 1. The battery box 5 provides power to the marine engine 6, hydrophone 9 and solar power.

[0031] Reference Figure 5 The main engine 6 is fastened to the aluminum frame of the top of the hull 1 by clamps 10 and bolts 11. The main engine 6 provides power to the hull. The main engine of this application has a built-in noise analysis module and uses a hydrophone 9 to detect the depth of the hydrophone. The noise analysis module and the hydrophone depth adjustable mechanism work together to enable the system to intelligently select the best monitoring depth according to the real-time underwater environment, adaptively avoid strong noise areas or acoustic interference sources in the water layer, and ensure that the acquisition of finless porpoise signals is always in the optimal signal-to-noise ratio state.

[0032] It is important to note that the hydrophone 9 (underwater microphone) is the core detection element, responsible for collecting underwater acoustic signals emitted by the Yangtze finless porpoise. The surface host 6, mounted above the solar panel, not only receives, processes, and transmits the acoustic data collected by the hydrophone, but also has a built-in real-time noise spectrum analysis module capable of identifying and quantifying the self-noise of the floating vessel and the underwater environmental noise levels. The system's hydrophone depth adjustment mechanism, combined with the noise analysis results from the surface host, adaptively adjusts the extension length of the hydrophone support rod, placing the hydrophone at the water layer with minimal impact from environmental noise and the vessel's self-noise, or at the optimal acoustic channel depth for the finless porpoise signal, thus achieving proactive adaptive optimization of the acoustic environment.

[0033] Reference Figure 3 and Figure 4 The solar bracket 7 is fixed to the aluminum profile frame on the top of the hull 1. The top of the solar bracket 7 is designed with an inclined panel, on which solar panels are installed. The bottom of the inclined panel is detachably fixed to the aluminum profile frame on the top of the hull 1 by the support legs.

[0034] Reference Figure 1On the hull 1 and on one side of the aluminum profile frame, there are ship light groups 13 and light group solar panels 14, wherein the light group solar panels 14 can provide solar energy for the ship light groups 13; there are also bollards 15 at the top of the hull 1 at the bow.

[0035] Appendix Figure 3 The exhibition showcases the effect of other structural components mounted on the aluminum profile framework, including the detector bracket 4, solar panel bracket 7, battery box 5, and the main unit on the water 6. Through a rational layout, the limited space is fully utilized; the battery box 5 is placed below the solar panel bracket 7, which also provides some rain protection.

[0036] The energy source of this application comes from the solar panels on the solar bracket 7. The solar panels convert light energy into electrical energy and store it in the batteries in the battery box 5. The batteries power the hydrophone 9 and the aquatic host 6 to ensure the normal operation of the device. The finless porpoise signal detected by the hydrophone 9 is transmitted to the aquatic host 6, and then sent back to the monitoring unit by the aquatic host 6 to achieve the purpose of finless porpoise detection.

[0037] This application addresses the issue of the battery box 5 and its internal batteries being too heavy, as simply fixing them to the aluminum profile with bolts would not provide sufficient strength. Therefore, an aluminum profile is placed around the battery box 5 to achieve horizontal reinforcement, while the main unit 6 is fixed to the aluminum profile using T-bolts 11 and clamps 10. Elevating the main unit 6 with the aluminum profile optimizes signal transmission; the elevated portion uses aluminum profiles as diagonal ribs to enhance structural stability. In this application, the aluminum profile is tightly fixed to the cross-shaped bollard 2 with T-bolts 11 and clamps 10, and the addition of diagonal ribs further improves structural stability.

[0038] In recent years, industrial aluminum profiles have become increasingly popular as a structural construction method. Industrial aluminum profiles are alloy materials with aluminum as the main component, formed by hot-melt extrusion of aluminum rods. They come in various cross-sectional shapes, and by adjusting the alloy ratio, profiles with different mechanical properties and suitable for different applications can be produced. After surface oxidation treatment, they are not only aesthetically pleasing and resistant to dirt, but also easy to clean of oil stains. When assembling products, different specifications of profiles can be selected according to load-bearing requirements, and connected with specialized accessories, eliminating the need for welding. This offers advantages such as environmental friendliness, convenient installation and disassembly, and lightweight transportability. Industrial aluminum profiles, with their modularity, high strength, weld-free operation, environmental friendliness, and ease of assembly and disassembly, offer a solution to the aforementioned problems.

[0039] In view of the above characteristics, this application considers using industrial aluminum profiles for structural design, combined with suitable solar panels, to non-destructively integrate them with the existing floating hull, ultimately constructing a stable and reliable finless porpoise detection platform. Simultaneously, the platform's aluminum profiles are connected via designed flexible connectors and incorporate an adaptive height adjustment device for hydrophone monitoring equipment to actively suppress hull noise interference and adaptively optimize the hydrophone deployment depth. This platform combines modular design, non-destructive fixing, flexible vibration reduction, and adaptive acoustic adjustment capabilities, significantly improving the signal-to-noise ratio and reliability of acoustic monitoring of the Yangtze finless porpoise.

[0040] The above embodiments are only used to illustrate the technical solutions of the present invention, and are not intended to limit it. Although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features. Such modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. An acoustic monitoring device for Yangtze finless porpoises based on a buoy, comprising a hull (1), characterized in that, An aluminum profile frame is installed at the top and stern of the hull (1), as well as a hydrophone mechanism, a marine engine (6) and a power supply mechanism that are detachably fastened to the frame. The hydrophone mechanism, the marine engine (6) and the power supply mechanism are all equipped with shock absorption and noise reduction components at the connection points between them and the aluminum profile frame. The marine engine (6) has a built-in noise analysis module. The hydrophone mechanism and the power supply mechanism are both connected to the marine engine (6). The hydrophone mechanism includes a detector bracket (4) fixed on an aluminum profile frame, a hydrophone support rod (8) vertically installed inside the detector bracket (4), and a hydrophone (9) fixed at the bottom of the hydrophone support rod (8), wherein the hydrophone (9) can penetrate deep into the river.

2. The acoustic monitoring device for Yangtze finless porpoises based on a buoy as described in claim 1, characterized in that: The aluminum profile frame is detachably fixed to the cross-shaped bollard (2) and the low guardrail (3) set on the top of the hull (1) by clamps (10).

3. The acoustic monitoring device for Yangtze finless porpoises based on buoy buoys according to claim 2, characterized in that: Two sets of cross-shaped bollards (2) are provided, and the two sets of cross-shaped bollards (2) are symmetrically fixed on both sides of the top of the hull (1). Two sets of low guardrails (3) are provided, and the two sets of low guardrails (3) are located on one side of the two sets of cross-shaped bollards (2). The two sets of low guardrails (3) are symmetrically fixed on both sides of the top of the hull (1).

4. The acoustic monitoring device for Yangtze finless porpoises based on a buoy as described in claim 1, characterized in that: The vibration damping and noise reduction components include flexible isolation pads or elastic connectors.

5. The acoustic monitoring device for Yangtze finless porpoises based on a buoy as described in claim 1, characterized in that: The power supply mechanism includes a battery box (5), which is connected to the hydrophone mechanism and the main watercraft (6) respectively, and is horizontally reinforced by aluminum profiles around the battery box (5).

6. The acoustic monitoring device for Yangtze finless porpoises based on a buoy as described in claim 1, characterized in that: The main watercraft (6) is located above the power supply mechanism, and the main watercraft (6) is detachably fixed to the aluminum profile frame by clamps (10). The height of the main watercraft (6) is raised by the aluminum profile, and an aluminum profile is installed on one side of the raised part as a diagonal rib.

7. The acoustic monitoring device for Yangtze finless porpoises based on a buoy as described in claim 1, characterized in that: On the top of the hull (1) and on one side of the aluminum profile frame, there are onboard lights (13) and lights solar panels (14), wherein the lights solar panels (14) are connected to the onboard lights (13).

8. The acoustic monitoring device for Yangtze finless porpoises based on a buoy as described in claim 1, characterized in that: The hull (1) is also equipped with a bollard (15) at the top bow position.

9. The acoustic monitoring device for Yangtze finless porpoises based on a buoy as described in claim 1, characterized in that: A solar panel bracket (7) is detachably installed above the aluminum profile frame and above the power supply mechanism. The top of the solar panel bracket (7) is an inclined surface, and a solar panel is fixed on the inclined surface.

10. An adaptive noise reduction method for the acoustic monitoring device for Yangtze finless porpoises based on a buoy as described in any one of claims 1-9, characterized in that, The steps include the following: The floating main unit (6) has a built-in real-time noise analysis module that can identify and quantify the self-noise of the floating vessel and the underwater environmental noise level. The depth of the hydrophone (9) can be combined with the noise analysis results of the floating main unit (6) to adaptively adjust the extension length of the hydrophone support rod, placing the hydrophone in the water layer with the least influence of environmental noise and hull self-noise or the optimal acoustic channel depth of the finless porpoise signal, thereby realizing active adaptive optimization of the acoustic environment. During monitoring, the power supply unit provides power to the hydrophone (9) and the floating host (6) to ensure the normal operation of the device; the finless porpoise signal detected by the hydrophone (9) is transmitted to the floating host (6), and then sent back to the monitoring unit by the floating host (6) to achieve the purpose of finless porpoise detection.

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