An acoustic source localization system based on a drone platform

Abstract

The application relates to the technical field of unmanned aerial vehicle search and rescue, and discloses a sound source positioning system based on an unmanned aerial vehicle platform, which comprises a flying vehicle, a closed bin, a main image acquisition module, a noise reduction module, an anti-inertia damping release module, a sound acquisition module, a collection control module and a micro image acquisition module. The anti-inertia damping release module is arranged in the inside of the closed bin and is used for adjusting the distance between the main image acquisition module and the sound acquisition module, so that the sound acquisition precision in a dense forest area is improved. The sound acquisition module and the main image acquisition module are separated and arranged in parallel by using the anti-inertia damping release module, time delay positioning is combined, a positioning mode of high-position sound acquisition and low-position sound acquisition is realized, the influence of the dense forest on sound energy reduction is reduced by using the crown-adhering flight of the sound acquisition mechanism, and the sound acquisition quality is poor when the sound acquisition is applied to mountainous areas and dense forest search and rescue, the low-position flight image acquisition area is too small, and the search and rescue precision and the search and rescue quality are improved.

Description

Technical Field

[0001] This invention relates to the field of drone search and rescue technology, specifically a sound source localization system based on a drone platform. Background Technology

[0002] Currently, by using multiple sound acquisition units to collect sound from a unified sound source and combining the time delay of the sound from multiple sound acquisition units with the distribution of microphones, the approximate location of the sound source can be determined. When applying sound source localization to rescue operations, images and sounds can be combined. By using high-altitude image acquisition from drones, more comprehensive image information can be obtained. Sound source localization can be used to quickly locate the target area and improve rescue efficiency.

[0003] However, there are certain problems when applying it to mountainous or dense forest environments:

[0004] Because of the influence of trees in mountainous and dense forest areas, sound energy is reduced when it passes through trees and leaves due to the density of the leaves, resulting in reflection, projection, and absorption. This shortens the transmission distance of the sound energy. At the same time, the influence of trees means that the drone itself needs to fly higher than the trees to obtain a basic distance. However, if the drone flies too close to the treetops, the image acquisition area is too small. Therefore, for dense forests and mountainous areas, the drone's flight altitude needs to be increased beyond the basic distance to increase the acquisition area. However, this results in the drone flying too high, and the sound source is reduced due to the influence of trees. In addition, due to the slope, the drone will fly almost parallel to the slope to ensure the stability of the image acquisition range. In this case, the drone is likely to completely miss the sound source area, preventing the sound acquisition device from entering the sound source acquisition area and delaying the best rescue opportunity.

[0005] Due to the obstruction of visibility caused by dense forest, the drone, after acquiring the location information of the sound source above the forest, could not accurately identify the person being rescued because the image acquisition was blocked. At this time, rashly entering the forest could easily cause the drone to be damaged by tree branches, resulting in the suspension of the rescue. If information below the dense forest could not be obtained, it would be impossible to determine whether the sound source was the person to be rescued. Since sound source identification mainly relies on the sound source frequency, there is an error involved. If the rescue team discovers that the person is not the one to be rescued, it would further delay the rescue opportunity. Summary of the Invention

[0006] The purpose of this invention is to provide a sound source localization system based on an unmanned aerial vehicle (UAV) platform to solve the problems mentioned in the background art.

[0007] To achieve the above objectives, the present invention provides the following technical solution:

[0008] A sound source localization system based on an unmanned aerial vehicle (UAV) platform includes an aircraft, an enclosed cabin, a main image acquisition module, a noise reduction module, an anti-inertial damping release module, a sound acquisition module, a collection control module, and a micro-image acquisition module.

[0009] The main image acquisition module is fixedly connected to the bottom of the enclosed chamber. The sound source location is obtained based on the sound time delay collected by the six ring-shaped sound acquisition units of the sound acquisition module. The main image acquisition module adjusts the image acquisition direction according to the sound source location.

[0010] The anti-inertia damping release module is located inside the enclosed chamber and is used to adjust the distance between the main image acquisition module and the sound acquisition module to improve the sound acquisition accuracy in dense forest areas.

[0011] The collection control module is located between the anti-inertia damping release module and the sound acquisition module. It is used to open the sound acquisition unit cluster after passing through the dense forest, further improving the sound acquisition accuracy in the dense forest area. At the same time, the micro-image acquisition module obtains the sound source location based on the sound time delay collected by the sound acquisition unit, acquires image information of the sound source location under the dense forest, and obtains the accurate location.

[0012] As a further embodiment of the present invention: a main noise reduction unit is fixedly connected to the bottom of the noise reduction module, and the six sound acquisition units are all located inside the main noise reduction unit. A secondary noise reduction unit is fixedly connected to the end of the extension rod, and the sound acquisition unit is installed inside the secondary noise reduction unit.

[0013] As a further embodiment of the present invention: the anti-inertia damping release module includes a winding unit and a traction module. The traction module is wound around the outside of the winding unit. The traction module includes a plurality of staggered main chain plates and secondary chain plates. The main chain plates and the secondary chain plates are rotatably connected end to end. The main chain plates and the secondary chain plates are elastically rotatably connected by a forward and reverse torsion spring. Under static conditions, the main chain plates and the secondary chain plates are perpendicularly collinear.

[0014] As a further embodiment of the present invention: the collection control module includes a main compartment, a gathering unit, a lifting unit, and an extension rod. The extension rod is rotatably connected to the bottom of the main compartment. A torsion spring rotation mechanism is provided between the extension rod and the main compartment. A micro-image acquisition module is fixedly connected to the middle position of the bottom of the main compartment. When the torsion spring rotation mechanism is static, the secondary noise reduction unit is located above the micro-image acquisition module.

[0015] As a further embodiment of the present invention: the retractable unit is slidably connected to the outside of the main compartment, the lifting unit drives the retractable unit to slide, the bottom of the retractable unit has a flared structure, and the inner wall of the retractable unit is in contact with the extension rod.

[0016] As a further aspect of the present invention: the enclosed chamber and the main noise reduction unit are connected by a pipe, and the outer diameter of the flared opening of the closing unit is larger than the inner diameter of the pipe between the enclosed chamber and the main noise reduction unit.

[0017] Compared with the prior art, the beneficial effects of the present invention are:

[0018] This invention utilizes an anti-inertial damping release module to separate and parallelize the sound acquisition module and the main image acquisition module. Combined with time-delay positioning, it achieves a positioning method of high-level acquisition and low-level sound collection. By utilizing the canopy-hugging flight of the sound acquisition mechanism, it reduces the impact of dense forest on sound energy reduction. This improves search and rescue accuracy and quality in areas with poor sound acquisition quality and small low-level flight image acquisition areas during mountain and dense forest search and rescue operations. Simultaneously, by using a collection control module in conjunction with a micro-image acquisition module and further combining time-delay positioning, it ensures the safety of the aircraft while allowing it to penetrate deep into the dense forest to further collect sound and determine direction before acquiring images under the dense forest. This avoids the influence of dense forest on the image and sound energy. When the positioning area image acquired by the main image acquisition module is covered by dense forest, a secondary acquisition is performed, thus making rescue operations more accurate. Attached Figure Description

[0019] To more clearly illustrate the technical solutions in the embodiments of the present invention, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0020] Figure 1 This is a schematic diagram of a slope search system for sound source localization based on an unmanned aerial vehicle (UAV) platform.

[0021] Figure 2 This is a schematic diagram of a sound source localization system based on an unmanned aerial vehicle (UAV) platform for deep forest search.

[0022] Figure 3 This is a schematic diagram illustrating the module coordination in different modes of a sound source localization system based on an unmanned aerial vehicle (UAV) platform.

[0023] Figure 4 A three-dimensional schematic diagram of an aircraft equipped with a sound source localization system based on an unmanned aerial vehicle (UAV) platform.

[0024] Figure 5A front view schematic diagram of an aircraft equipped with a sound source localization system based on an unmanned aerial vehicle (UAV) platform;

[0025] Figure 6 This is a side view sectional diagram of an aircraft equipped with a sound source localization system based on an unmanned aerial vehicle (UAV) platform.

[0026] In the diagram: 100, aircraft; 200, enclosed cabin; 1, main image acquisition module; 2, noise reduction module; 21, main noise reduction unit; 22, secondary noise reduction unit; 3, anti-inertia damping release module; 31, winding unit; 32, traction module; 321, main chain plate; 322, secondary chain plate; 4, sound acquisition module; 41, sound acquisition unit; 5, collection control module; 51, main cabin; 52, retraction unit; 53, lifting unit; 54, extension rod; 541, torsion spring rotation mechanism; 6, micro-image acquisition module. Detailed Implementation

[0027] Figures 1 to 6 Composition of the present invention

[0028] It includes an aircraft 100, a closed cabin 200, and also includes a main image acquisition module 1, a noise reduction module 2, an anti-inertial damping release module 3, a sound acquisition module 4, a collection and control module 5, and a micro-image acquisition module 6;

[0029] The enclosed compartment 200 is fixed below the aircraft 100. Its main purpose is to house the subsequent installation structure in a relatively enclosed space and protect the module in flight.

[0030] The main image acquisition module 1 is installed below the aircraft 100. Due to the presence of the enclosed compartment 200, if the main image acquisition module 1 is installed directly below the enclosed compartment 200, it will interfere with some structures. If the main image acquisition module 1 is installed on the side of the enclosed compartment 200, half of the horizontal rear area will be blocked by the enclosed compartment 200. To solve the problem of the main image acquisition module 1, a revolution rail can be set outside the enclosed compartment 200, so that the main image acquisition module 1 can rotate around the center of the enclosed compartment 200 along the circular revolution rail, thereby realizing the image acquisition of the main image acquisition module 1 in a different direction. The main image acquisition module 1 is mainly used to acquire images below at the flight altitude of the aircraft 100, thereby increasing the image acquisition area and improving search and rescue efficiency.

[0031] Since the aircraft 100 will generate wind noise and propeller noise during flight, the noise reduction module 2 mechanically blocks the noise of the main image acquisition module 1 to reduce the wind noise and propeller noise generated during flight.

[0032] The sound acquisition module 4 is installed inside the noise reduction module 2, which is located below the enclosed chamber 200. At this time, the sound acquisition module 4 can be protected by the enclosed chamber 200, reducing some noise. Meanwhile, the sound acquired by the sound acquisition module 4 adopts a frequency filtering audio noise reduction algorithm based on Fourier transform. The noisy time-domain waveform is converted into a noisy spectrum through FFT, removing the noise signal with higher frequency components and leaving the distress signal with relatively lower frequency components. Then, the distress signal after removing the noise signal can be obtained through inverse Fourier transform (IFFT).

[0033] The main image acquisition module 1 is fixedly connected to the bottom of the enclosed chamber 200. The sound source location is obtained based on the sound time delay collected by the six ring-shaped sound acquisition units 41 of the sound acquisition module 4. The main image acquisition module 1 adjusts the image acquisition location according to the sound source location.

[0034] The sound acquisition module 4 has six sound acquisition units 41. Since the same sound source will produce a time difference when it is transmitted to microphones at different positions, the time delay multiplied by the speed of sound can be used to obtain the time difference, thereby obtaining the approximate location of the sound source. At this time, the approximate location of the sound source is applied to the image information obtained by the high-position main image acquisition module 1. Since the main image acquisition module 1 has a wide coverage area, it is difficult for the small error of the sound source location to deviate from the image coverage area of ​​the main image acquisition module 1. Therefore, it can be applied to open areas and the target location can be found quickly.

[0035] The anti-inertia damping release module 3 is installed inside the enclosed chamber 200 and is used to adjust the distance between the main image acquisition module 1 and the sound acquisition module 4 to improve the sound acquisition accuracy in dense forest areas.

[0036] The anti-inertia damping release module 3 is designed to meet the image acquisition area requirements of the main image acquisition module 1 while lowering the altitude of the sound acquisition module 4 during the high-flying state of the aircraft 100. This creates a positional difference between the main image acquisition module 1 and the sound acquisition module 4. The purpose of creating this positional difference is twofold: firstly, it reduces the impact of continuous noise on sound acquisition. At this time, there is a certain distance between the propeller of the aircraft 100 and the sound acquisition module 4. The sound energy decreases during noise transmission, thus reducing the impact of continuous noise on the acquisition effect of the sound acquisition unit 41. Secondly, since the sound acquisition module 4 does not need to consider the image area, it is better for the sound acquisition module 4 to be as close to the sound source as possible. At this time, the sound acquisition module 4 can fly close to the top of the tree canopy with the drone. At this time, the sound acquisition module 4 is closest to the sound source under the flight conditions, making it easier to acquire the weaker distress call and improve the sound acquisition accuracy. However, since it is easily affected by inertia during flight, it is necessary to overcome inertia and avoid the sound acquisition module 4 from swaying after hovering.

[0037] The collection control module 5 is set between the anti-inertia damping release module 3 and the sound acquisition module 4. It is used to open the sound acquisition unit 41 after it passes through the dense forest, which further improves the sound acquisition accuracy in the dense forest area. At the same time, the micro-image acquisition module 6 obtains the sound source location based on the sound time delay collected by the sound acquisition unit 41, and acquires the image information of the sound source location under the dense forest to obtain the accurate location.

[0038] The collection control module 5 is designed to gather, cluster, and expand the sound acquisition unit 41. When the sound acquisition unit 41 is flying normally below the aircraft 100, it can be clustered inside the main noise reduction unit 21, where noise is processed. In this case, the time delay calculation uses a clustering parameter because the spacing of the sound acquisition units 41 changes. Furthermore, when the image at the sound source's location is covered by dense forest, the collection control module 5 adjusts the sound acquisition module 4 to a clustered state, making the multiple extension rods 54 nearly vertical. This further reduces the spacing of the sound acquisition units 41, creating an approximately cylindrical structure. The anti-inertia damping release module 3 then controls the sound acquisition module 4. As the sound acquisition module 4 is released downwards, it is less likely to interfere with tree branches, making it easier for it to enter the dense forest. After the sound acquisition module 4 enters the dense forest, the sound acquisition unit 41 is opened by the collection control module 5. The opened micro-image acquisition module 6 will not be interfered with by the extension rod 54 and the sound acquisition unit 41, thus reducing the interference on the image acquisition range of the micro-image acquisition module 6. When descending through the sound acquisition module 4, since the sound acquisition module 4 does not have a structure with frequent and high-speed movement, it is less likely to apply a large amount of kinetic energy to the tree branches. This ensures the safety of the aircraft 100 while acquiring more comprehensive image information, and even more detailed regional environment information for rescuers, providing a reference for rescue.

[0039] The bottom of the noise reduction module 2 is fixedly connected to the main noise reduction unit 21, and the six sound acquisition units 41 are all located inside the main noise reduction unit 21. The ends of the extension rod 54 are all fixedly connected to the secondary noise reduction unit 22, and the sound acquisition units 41 are installed inside the secondary noise reduction unit 22.

[0040] Both the main noise reduction unit 21 and the auxiliary noise reduction unit 22 are funnel-shaped. In order to further improve the noise cancellation effect, windproof covers are set on the outside of the main noise reduction unit 21 and the auxiliary noise reduction unit 22, and sound-absorbing cotton is set inside the main noise reduction unit 21 and the auxiliary noise reduction unit 22 to further eliminate noise.

[0041] The anti-inertia damping release module 3 includes a winding unit 31 and a traction module 32. The traction module 32 is wound outside the winding unit 31. The traction module 32 includes several staggered main chain plates 321 and secondary chain plates 322. The main chain plates 321 and secondary chain plates 322 are rotatably connected end to end. The main chain plates 321 and secondary chain plates 322 are elastically rotatably connected by forward and reverse torsion springs. Under static conditions, the main chain plates 321 and secondary chain plates 322 are perpendicular and collinear.

[0042] The winding unit 31 employs a brake motor and roller structure to wind up the traction module 32. To overcome inertia during forward movement and the transition between forward and stop states, the traction module 32 uses a staggered hinge between the main chain plate 321 and the auxiliary chain plate 322. Since the main chain plate 321 and the auxiliary chain plate 322 are hinged using pin joints, they can only slide in relative directions, such as forward / backward or left / right. The advantage of this method is that when the travel direction is not in the hinged direction of the main chain plate 321 and the auxiliary chain plate 322, the movement can be achieved through the hinge between the main chain plate 321 and the auxiliary chain plate 322. The mechanical cooperation of 322 itself resists inertia. When the flight direction is consistent with the hinge direction of the main chain plate 321 and the secondary chain plate 322, the inertial influence generated by driving and stopping will be applied to the forward and reverse torsion springs, thereby absorbing energy through the deformation of the torsion springs, accelerating the energy loss generated by inertia, and improving the balance speed of the sound acquisition module 4. At the same time, in order to further ensure stability, unidirectional rotation can also be adopted. A locking block is set in one of the connection directions of the main chain plate 321 and the secondary chain plate 322, so that the main chain plate 321 and the secondary chain plate 322 can only rotate in the winding bending direction. At this time, in conjunction with the unidirectional torsion spring, the inertial energy loss is even faster.

[0043] The collection control module 5 includes a main compartment 51, a gathering unit 52, a lifting unit 53, and an extension rod 54. The extension rod 54 is rotatably connected to the bottom of the main compartment 51. A torsion spring rotating mechanism 541 is provided between the extension rod 54 and the main compartment 51. A micro-image acquisition module 6 is fixedly connected to the middle of the bottom of the main compartment 51. When the torsion spring rotating mechanism 541 is static, the auxiliary noise reduction unit 22 is located above the micro-image acquisition module 6. The gathering unit 52 is slidably connected to the outside of the main compartment 51. The lifting unit 53 drives the gathering unit 52 to slide. The bottom of the gathering unit 52 has a flared structure, and the inner wall of the gathering unit 52 is in contact with the extension rod 54.

[0044] The main compartment 51 primarily functions as a carrier. The end of the traction module 32 is fixedly connected to the top of the main compartment 51. At this time, the extension rod 54 rotates at the bottom of the main compartment 51, extending outwards in all directions. The torsion spring rotating mechanism 541 is stationary, simply overcoming gravity. However, when the lifting unit 53 pushes the retracting unit 52 downwards, the bottom diameter of the retracting unit 52 is larger than its top diameter. As the retracting unit 52 descends, its inclined surface contacts the extension rod 54, causing the extension rod 54 to be subjected to the thrust of the retracting unit 52 and the effect of its reduced diameter. This causes the end of the extension rod 54 with the sound acquisition unit 41 to converge until the minimum diameter of the retracting unit 52 contacts the extension rod 54. When the extension rod 54 is nearly vertical, it achieves the purpose of clustering. When the winding unit 31 drives the traction module 32 to descend, the clustered sound acquisition module 4 passes through the dense forest and enters the area under the tree canopy more easily. At this time, the extension rod 54 is opened to expose the micro-image acquisition module 6. The secondary noise reduction unit 22 is located above the micro-image acquisition module 6, thereby avoiding interference with the acquired image of the micro-image acquisition module 6. In order to make the influence of the secondary noise reduction unit 22 on the micro-image acquisition module 6 less, the height of the micro-image acquisition module 6 is extended downward through the vertical rod, thereby further reducing the influence of the extended rod 54 on the micro-image acquisition module 6 after it is opened.

[0045] The enclosed chamber 200 is connected to the main noise reduction unit 21 through a pipe, and the outer diameter of the flared opening of the closing unit 52 is larger than the inner diameter of the pipe between the enclosed chamber 200 and the main noise reduction unit 21.

[0046] To prevent the sound acquisition module 4 from shaking during flight, when the brake motor of the winding unit 31 pulls the traction module 32 upward, the flared end of the winding unit 52 will enter the pipe between the sealed chamber 200 and the main noise reduction unit 21, preventing the sound acquisition module 4 from moving upward. At the same time, when moving downward, the winding unit 31 will lock up, thus fixing the sound acquisition module 4.

[0047] Usage process of this invention

[0048] For mountainous and dense forest areas, the flight altitude of the aircraft 100 is based on the base altitude plus the optimal image coverage altitude. At this time, the main image acquisition module 1 located above the aircraft 100 can acquire image information within the optimal range. The main noise reduction unit 21 and the secondary noise reduction unit 22 work together to reduce noise. The parameters for calculating the time delay azimuth are based on the convergence distance of the sound acquisition unit 41 to calculate the sound source azimuth. When the dense forest coverage is too large and affects the acquisition of surface images, the slope separation mode is activated.

[0049] In slope separation mode, the aircraft 100 flies parallel to the slope, thereby reducing the variation in the image acquisition coverage area of ​​the main image acquisition module 1. At this time, the traction module 32 is released through the rewind unit 31, causing the collection control module 5 to carry the sound acquisition module 4 downward in a retracted state. The sound acquisition module 4 slides out from the main noise reduction unit 21. Through the suspension effect of the traction module 32, the sound acquisition module 4 is positioned above the tree canopy and moves in coordination with the aircraft 100. At this time, the sound acquisition module 4 is closer to the ground surface area, and the accuracy of the acquired sound source information is higher. At the same time, the sound acquisition module 4 is further away from the aircraft 100, reducing the interference of continuous noise. The noise reduction of the sound acquisition unit 41 is performed by the rewind unit 52, and the sound source acquisition quality is improved in mountainous and dense forest areas when the sound energy is reduced.

[0050] In the dense forest depth module, when the dense forest coverage in the image acquired by the main image acquisition module 1 is too high, the height of the sound acquisition module 4 is lowered by the retraction unit 31. Simultaneously, the lifting unit 53 pushes the folding unit 52 down, causing the folding unit 52 to converge the extension rod 54. The lifting unit 53 uses an electric push rod. After the sound acquisition module 4 is converged, the drone selects the most suitable depth position according to the terrain, stops above the depth position, and continues to release by the retraction unit 31, allowing the sound acquisition module 4 to penetrate deeper into the dense forest. At this point, the lifting unit 53 drives the folding unit 52 to rise, twisting... The spring rotation mechanism 541 resets, causing the extension rod 54 to open. At this time, the calculated time delay direction is based on the distance after the extension rod 54 opens. At this time, the auxiliary noise reduction unit 22 rotates upward, and the micro-image acquisition module 6 located in the center is exposed. Since most injured people are on the ground, the inability to acquire images above the micro-image acquisition module 6 has little impact. It is only necessary to acquire the specific situation below the tree canopy. Through the secondary calculation of time delay, the acquisition direction of the micro-image acquisition module 6 is adjusted to determine the accurate location of the person to be rescued, providing more detailed environmental information and providing rescue reference for rescuers.

[0051] The above description is merely a preferred embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any equivalent substitutions or modifications made by those skilled in the art within the scope of the technology disclosed in the present invention, based on the technical solution and inventive concept of the present invention, should be covered within the scope of protection of the present invention.

Claims

1. A sound source localization system based on an unmanned aerial vehicle (UAV) platform, comprising an aircraft (100) and a closed compartment (200), characterized in that: It also includes a main image acquisition module (1), a noise reduction module (2), an anti-inertia damping release module (3), a sound acquisition module (4), a collection control module (5), and a micro-image acquisition module (6). The main image acquisition module (1) is fixedly connected to the bottom of the closed chamber (200). The sound source location is obtained based on the sound time delay collected by the six ring-shaped sound acquisition units (41) of the sound acquisition module (4). The main image acquisition module (1) adjusts the image acquisition location according to the sound source location. The anti-inertia damping release module (3) is located inside the enclosed chamber (200) and is used to adjust the distance between the main image acquisition module (1) and the sound acquisition module (4) to improve the sound acquisition accuracy in dense forest areas. The collection control module (5) is located between the anti-inertia damping release module (3) and the sound acquisition module (4). It is used to open the sound acquisition unit (41) after it passes through the dense forest, thereby further improving the sound acquisition accuracy in the dense forest area. At the same time, the micro-image acquisition module (6) obtains the sound source location based on the sound delay acquired by the sound acquisition unit (41), acquires the image information of the sound source location under the dense forest, and obtains the accurate location. The anti-inertia damping release module (3) includes a winding unit (31) and a traction module (32). The traction module (32) is wound up outside the winding unit (31). The traction module (32) includes several staggered main chain plates (321) and secondary chain plates (322). The main chain plates (321) and the secondary chain plates (322) are rotatably connected end to end. The main chain plates (321) and the secondary chain plates (322) are elastically rotatably connected by a forward and reverse torsion spring. When the forward and reverse torsion spring is static, the main chain plates (321) and the secondary chain plates (322) are vertically collinear.

2. The sound source localization system based on an unmanned aerial vehicle platform according to claim 1, characterized in that: The bottom of the noise reduction module (2) is fixedly connected to the main noise reduction unit (21), and the six sound acquisition units (41) are all located inside the main noise reduction unit (21). The ends of the extension rod (54) are all fixedly connected to the secondary noise reduction unit (22), and the sound acquisition unit (41) is installed inside the secondary noise reduction unit (22).

3. The sound source localization system based on an unmanned aerial vehicle platform according to claim 2, characterized in that: The collection control module (5) includes a main compartment (51), a gathering unit (52), a lifting unit (53), and an extension rod (54). The extension rod (54) is rotatably connected to the bottom of the main compartment (51). A torsion spring rotating mechanism (541) is provided between the extension rod (54) and the main compartment (51). A micro-image acquisition module (6) is fixedly connected to the middle position of the bottom of the main compartment (51). When the torsion spring rotating mechanism (541) is static, the auxiliary noise reduction unit (22) is located above the micro-image acquisition module (6).

4. A sound source localization system based on an unmanned aerial vehicle (UAV) platform according to claim 3, characterized in that: The folding unit (52) is slidably connected to the outside of the main compartment (51). The lifting unit (53) drives the folding unit (52) to slide. The bottom of the folding unit (52) is an flared structure. The inner wall of the folding unit (52) is in contact with the extension rod (54).

5. A sound source localization system based on an unmanned aerial vehicle (UAV) platform according to claim 3, characterized in that: The enclosed chamber (200) and the main noise reduction unit (21) are connected by a pipe, and the outer diameter of the flared opening of the gathering unit (52) is larger than the inner diameter of the pipe between the enclosed chamber (200) and the main noise reduction unit (21).

Images