Unmanned aerial vehicle-mounted acoustic detection system

Abstract

The utility model discloses an unmanned aerial vehicle-mounted acoustic detection system. The unmanned aerial vehicle-mounted acoustic detection system comprises an acoustic array, a storage battery, a data acquisition box fixed on an unmanned aerial vehicle, and a signal processing module arranged in the data acquisition box, the acoustic array comprises a microphone which is arranged outside the data acquisition box, is connected with the signal processing module and is used for detecting an acoustic signal; the signal processing module is used for processing sound signals detected by the acoustic array; the storage battery is used for supplying power to the signal processing module. According to the unmanned aerial vehicle-mounted acoustic detection system, the acoustic array, the storage battery and the data acquisition box provided with the signal processing module are arranged on the unmanned aerial vehicle, large-area acoustic target monitoring is achieved through flight of the unmanned aerial vehicle, and the problem that a monitoring area is limited due to static arrangement of the acoustic detection system in a target area can be solved.

Description

Technical Field

[0001] The present application relates to the field of target detection, and in particular to an unmanned aerial vehicle-borne acoustic detection system. Background Art

[0002] Acoustic information is an important part of physical information. Acoustic information acquisition and related signal processing can be used to estimate the properties and state information of acoustic targets, as well as the matching and inversion of corresponding environmental parameters. Acoustic monitoring, as a passive detection method, has the advantages of good concealment and resistance to electromagnetic interference, and can meet the needs of unmanned battlefield environment perception and acoustic detection and early warning. Existing acoustic detection equipment has a large aperture and is often arranged statically. It has poor maneuverability and is difficult to achieve target monitoring in a wide-area environment. Utility Model Content

[0003] The present application discloses an acoustic detection system carried by a drone. The acoustic detection system carried by a drone comprises: an acoustic array, a battery, a data acquisition box fixed on the drone, and a signal processing module arranged inside the data acquisition box;

[0004] The acoustic array includes a microphone disposed outside the data acquisition box and connected to the signal processing module, for detecting acoustic signals;

[0005] The signal processing module is used to process the acoustic signal detected by the acoustic array;

[0006] The storage battery is used to supply power to the signal processing module.

[0007] In a possible implementation, the acoustic array further includes a support rod connecting the microphone and the data acquisition box, which is used to adjust the position of the microphone relative to the data acquisition box by contraction or bending.

[0008] In a possible implementation, the acoustic array specifically includes three microphones located in the same plane and a single microphone perpendicular to the three microphones; among the three microphones, the positions of any two microphones have the same angle.

[0009] In a possible implementation manner, the microphone is provided with a windshield for eliminating the influence of wind noise during use.

[0010] In a possible implementation, the drone-borne acoustic detection system further includes a locator disposed on the drone; the locator is used to convert the coordinates of the acoustic signal detected by the acoustic array into a coordinate system of the drone.

[0011] In a possible implementation, the signal processing module adopts an architecture combining ARM and field programmable gate array FPGA.

[0012] In a possible implementation, the unmanned aerial vehicle acoustic detection system further includes a wireless communication module disposed inside the data acquisition box, for transmitting the acoustic signal processed by the signal processing module to the outside world.

[0013] In a possible implementation, the unmanned aerial vehicle acoustic detection system further includes a clock synchronization module disposed inside the data acquisition box, for synchronizing the timing of the acoustic signals detected by the acoustic array.

[0014] In a possible implementation, the clock synchronization module has a built-in constant temperature crystal oscillator or a rubidium clock for providing time information;

[0015] The clock synchronization module is specifically used to receive a time signal from a satellite, and use the time signal to correct the time information provided by the constant temperature crystal oscillator or the rubidium clock.

[0016] In a possible implementation, the drone-borne acoustic detection system further includes an inertial integrated navigation module disposed inside the data acquisition box, for positioning and navigating the drone.

[0017] The unmanned aerial vehicle (UAV)-mounted acoustic detection system disclosed in the present application can solve the problem of limited monitoring area due to static arrangement of the acoustic detection system in the target area by placing an acoustic array, a battery and a data acquisition box equipped with a signal processing module on the UAV and using the UAV to fly to achieve large-area acoustic target monitoring. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] In order to more clearly illustrate the technical solutions of the embodiments of the present application, the drawings required for use in the embodiments will be briefly introduced below. It should be understood that the following drawings only show certain embodiments of the present application and therefore should not be regarded as limiting the scope. For ordinary technicians in this field, other related drawings can be obtained based on these drawings without paying creative work.

[0019] Figure 1 One of the structural schematic diagrams of an unmanned aerial vehicle-borne acoustic detection system provided in an embodiment of the present application;

[0020] Figure 2 A second structural diagram of an unmanned aerial vehicle-borne acoustic detection system provided in an embodiment of the present application;

[0021] Figure 3 A third structural diagram of an unmanned aerial vehicle-borne acoustic detection system provided in an embodiment of the present application;

[0022] Figure 4A fourth structural diagram of an unmanned aerial vehicle-borne acoustic detection system provided in an embodiment of the present application;

[0023] Figure 5 A fifth structural diagram of an unmanned aerial vehicle-borne acoustic detection system provided in an embodiment of the present application;

[0024] Figure 6 A sixth structural diagram of an unmanned aerial vehicle-borne acoustic detection system provided in an embodiment of the present application;

[0025] Figure 7 The seventh structural schematic diagram of an unmanned aerial vehicle-borne acoustic detection system provided in an embodiment of the present application. DETAILED DESCRIPTION

[0026] The solution provided in this specification is described below in conjunction with the accompanying drawings.

[0027] In order to make the purpose, technical solution and advantages of the embodiments of the present application clearer, the technical solution in the embodiments of the present application will be described below in conjunction with the accompanying drawings. It should be noted that similar reference numerals and letters represent similar items in the following drawings, so once an item is defined in one drawing, it does not need to be further defined and explained in the subsequent drawings.

[0028] In the description of the embodiments of the present application, words such as "exemplary", "for example" or "for example" are used to indicate examples, illustrations or descriptions. Any embodiment or design described as "exemplary", "for example" or "for example" in the embodiments of the present application should not be interpreted as being more preferred or more advantageous than other embodiments or designs. Specifically, the use of words such as "exemplary", "for example" or "for example" is intended to present related concepts in a concrete way.

[0029] In the description of the embodiments of the present application, the term "and / or" is merely a description of the association relationship of associated objects, indicating that three relationships may exist. For example, A and / or B may represent: A exists alone, B exists alone, and A and B exist at the same time. In addition, unless otherwise specified, the term "plurality" means two or more.

[0030] In addition, the terms "first" and "second" are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the indicated technical features. Therefore, a feature defined as "first" or "second" may explicitly or implicitly include one or more of the features. The terms "include", "comprises", "has" and their variations all mean "including but not limited to", unless otherwise specifically emphasized.

[0031] Acoustic information is an important part of physical information. Acoustic information acquisition and related signal processing can be used to estimate the properties and state information of acoustic targets, as well as the matching and inversion of corresponding environmental parameters. Acoustic monitoring, as a passive detection method, has the advantages of good concealment and resistance to electromagnetic interference, and can meet the needs of unmanned battlefield environment perception and acoustic detection and early warning. Existing acoustic detection equipment has a large aperture and is often arranged statically. It has poor maneuverability and is difficult to achieve target monitoring in a wide-area environment.

[0032] Drones have the advantages of low cost, small size, easy to carry, and low risk to personnel. Drones can carry optical, infrared, electromagnetic and other system platforms, and play an important role in battlefield intelligence acquisition, battlefield reconnaissance, and map mapping.

[0033] In response to the above problems, the present application proposes an unmanned aerial vehicle (UAV)-borne acoustic detection system.

[0034] like Figure 1 The unmanned aerial vehicle-borne acoustic detection system shown includes: an acoustic array 1, a battery, a data acquisition box 2 fixed on the unmanned aerial vehicle, and a signal processing module arranged inside the data acquisition box 2;

[0035] The acoustic array 1 includes a microphone 11 disposed outside the data acquisition box 2 and connected to a signal processing module for detecting acoustic signals; the signal processing module is used to process the acoustic signals detected by the acoustic array 1; and a battery is used to power the signal processing module.

[0036] For example, if Figure 1 As shown, the data acquisition box 2 is fixed to the bottom of the drone by bolts; the microphone 11 is fixed to the data acquisition box 2 by a carbon fiber tube, and is connected to the signal processing module in the data acquisition box 2 by a data line; at the same time, the battery can also be set in the data acquisition box 2, and after the data acquisition box 2 is flipped open, the battery can be fixed to the bracket inside the data acquisition box 2 to power the signal processing module; in addition, Figure 2 , Figure 3 As shown, a power switch and a power indicator light can be provided outside the data acquisition box 2.

[0037] Next refer to Figure 1 As shown, the acoustic array 1 further includes a support rod 12 connecting the microphone 11 and the data acquisition box 2, and is used to adjust the position of the microphone 11 relative to the data acquisition box 2 by contraction or bending.

[0038] In a more specific embodiment, referring to Figure 4 , Figure 5 As shown, the acoustic array specifically includes: three microphones 11 located in the same plane, and a single microphone 11 perpendicular to the three microphones 11. For example, Figure 3 As shown, the UAV-borne acoustic detection system adopts a 4-element stereo array structure, and the number of microphones 11 is 4; wherein the three microphones 11 are located in the same plane, and the angle between any two microphones 11 is equal and 120°; a single microphone 11 is also provided which is perpendicular to the three microphones 11, and as shown in FIG. Figure 6 , Figure 7 As shown, the length of the support rod corresponding to the single microphone 11 is smaller than the length of the drone bracket.

[0039] During the process of large-area acoustic target detection, the acoustic array 1 may be interfered by the self-noise of the drone and the wind noise of the drone during rapid flight, resulting in an extremely low signal-to-noise ratio of the target acoustic signal collected by the drone-borne acoustic platform. At this time, in order to protect the microphone 11 from the influence of wind force and wind speed, the microphone 11 may be provided with a windshield for eliminating the influence of wind noise during use. The windshield can reduce the interference of wind noise on the microphone 11 and improve the clarity and accuracy of the acquired acoustic signal. In outdoor environments or situations where it is necessary to be exposed to the wind for a long time, the use of a windshield can effectively reduce the influence of wind noise and ensure the normal operation of the microphone 11. In addition, the windshield can also prevent debris or dust from entering the microphone 11, thereby extending the service life of the microphone 11.

[0040] In a possible implementation, the drone-borne acoustic detection system further includes a locator disposed on the drone; the locator is used to convert the coordinates of the acoustic signal detected by the acoustic array 1 into the coordinate system of the drone. The locator can be a simple marker or sensor device. According to the position and direction information provided by the locator, the direction and position of the acoustic array 1 can be adjusted so that its coordinate system has the same reference direction as the coordinate system of the drone; specifically, the x, y, and z axis directions of the acoustic signal coordinate system obtained by the acoustic array 1 are consistent with the x, y, and z axis directions of the drone, so that the spatial position of the acoustic signal can be accurately obtained, which is convenient for locating and analyzing the direction and position information of the sound source, and realizing specific applications such as sound source positioning and tracking.

[0041] In a possible implementation, the signal processing module adopts an architecture combining ARM and Field Programmable Gate Array (FPGA).

[0042] Specifically, the ARM processor is usually responsible for high-level control, data processing flow management and decision logic, while the FPGA is responsible for high-speed data processing, specific algorithm acceleration and other tasks. The signal processing module adopts this structure to achieve flexible data processing, and combining the advantages of both can achieve functions such as high-speed data processing, storage and complex algorithm calculation. At the same time, it can meet the needs of high-speed data processing and storage.

[0043] At the same time, the signal processing module adopts the ARM+FPGA structure to realize the real-time collection and analysis of the background noise of the drone through the ARM processor, and at the same time, the high-speed parallel processing capability of the FPGA is combined to realize the processing and feature extraction of the acquired acoustic signal. For example, with the help of the parallel computing capability of the FPGA, the background noise in the acoustic signal can be removed, and at the same time, complex signal processing algorithms and monitoring target signal feature extraction can be executed in the ARM, so as to realize the efficiency and accuracy of the acoustic signal processing of the signal processing module.

[0044] In addition, the signal processing module can also add double data rate third generation memory (Double Data Rate 3, DDR3) to meet the demand for high-speed data buffer, effectively improve the efficiency and stability of data processing, and ensure that there is enough data buffer when processing a large number of sound signals.

[0045] In a possible implementation, the unmanned aerial vehicle acoustic detection system further includes a clock synchronization module disposed inside the data acquisition box 2 , for synchronizing the timing of the acoustic signals detected by the acoustic array 1 .

[0046] Due to the different lengths of the acoustic signal transmission paths and the differences in processing circuits, there may be a slight time delay between the acoustic signals transmitted through different channels. The clock synchronization module can generate a unified time signal by using a high-precision clock, so that the acoustic signals transmitted through different channels can be aligned in time. In other words, the clock synchronization module sends a global time signal to each channel, and then each channel synchronizes its own acoustic signal according to the received time signal. For example, when performing specific applications such as sound source localization, signal analysis, and target identification, the clock synchronization module can accurately synchronize time to provide more accurate results.

[0047] In addition, through the clock synchronization module, the drone-mounted acoustic array can also achieve high-precision synchronous sound signal detection between multiple drones. For example, it can realize the collaborative operation of drone groups to complete search and rescue, environmental monitoring, agricultural operations and other tasks; and according to the mission requirements, the drone group can dynamically reorganize the structural topology, and the data collected by each drone can be synchronized with high precision for information fusion, realizing a more flexible and efficient way of cooperation.

[0048] In a specific embodiment, a constant temperature crystal oscillator or a rubidium clock is built into the clock synchronization module to provide time information; the clock synchronization module is specifically used to receive compressed time signals from satellites such as Beidou, Global Positioning System (GPS) and Global Navigation Satellite System (GNSS), and use the time signal to correct the time information provided by the constant temperature crystal oscillator or the rubidium clock.

[0049] In a possible implementation, the drone-borne acoustic detection system further includes an inertial integrated navigation module disposed inside the data acquisition box 2, for positioning and navigating the drone. The antenna of the inertial integrated navigation module is arranged on the drone fixing plate, and the inertial integrated navigation module is powered by a battery.

[0050] At the same time, in certain environments or geographical locations, such as in high-rise buildings, mountainous areas or urban canyons, a single GNSS system signal may be weak or unreceivable. In this case, the inertial integrated navigation module can use dual GNSS antennas to simultaneously receive position signals from multiple global navigation satellite systems such as GPS, GNSS, Beidou, etc., thereby obtaining more satellite observation values, reducing the impact of satellite position errors and signal shielding, and providing more accurate position information. In addition, the use of dual GNSS antennas can reduce the time for positioning solutions. Since signals from multiple satellite systems are received simultaneously, sufficient satellite observation values ​​can be obtained more quickly, and fast and effective positioning solutions can be performed, thereby shortening the initialization time for positioning.

[0051] In a possible implementation, the drone-borne acoustic detection system further includes a wireless communication module disposed inside the data acquisition box 2, for transmitting the acoustic signal processed by the signal processing module to the outside world.

[0052] For example, the wireless communication module is built into the data acquisition host box 2 and is powered by a battery. The wireless communication module antenna is arranged on the drone fixing plate and installed downward to transmit the sound signal detected by the microphone 11 to the control center.

[0053] It should be noted that the wireless communication module can also transmit the position signal obtained by the inertial navigation module and the time signal obtained by the clock synchronization module.

[0054] To adapt to the long-distance communication of drones to detect acoustic signals over a large range, the wireless communication module can select 900MHz and 2.4GHz data links; the low-frequency band 900MHz and 2.4GHz signals have less attenuation during transmission and can transmit data over a longer distance; at the same time, compared with high-frequency band signals, the 900MHz and 2.4GHz band signals have better ability to penetrate buildings, trees or other obstacles, thereby realizing real-time data exchange and communication connection with the control center, thereby realizing remote control, data transmission and mission command and other functions.

[0055] The present application provides an unmanned aerial vehicle (UAV)-borne acoustic detection system, and its working process is as follows: first, the UAV-borne acoustic detection system is started, and the acoustic array 1 is used to collect acoustic signals, and the collected acoustic signals are processed by a signal processing module, such as filtering the acoustic signals and removing background noise or storing the acoustic signals; the UAV power supply is started, and the UAV power supply system is independent of the power supply of the UAV-borne acoustic system. The UAV flight is controlled by the flight control system of the command center to realize acoustic monitoring of the target area under maneuverable flight.

[0056] In order to perform acoustic detection more accurately, after the collected acoustic signals are processed by the signal processing module, the position information can be obtained according to the inertial navigation module, and the acoustic signal can be timed according to the clock synchronization module; then the processed acoustic signal and position information are transmitted to the command center through the wireless communication module, realizing accurate monitoring of the target area under maneuverable flight.

[0057] The above specific implementation methods further illustrate the purpose, technical solutions and beneficial effects of the present application in detail. It should be understood that the above are only specific implementation methods of the present application and are not used to limit the protection scope of the present application. Any modifications, equivalent substitutions, improvements, etc. made on the basis of the technical solutions of the present application should be included in the protection scope of the present application.

Claims

1. An unmanned aerial vehicle acoustic detection system, characterized in that: include: An acoustic array (1), a storage battery, a data acquisition box (2) fixed on a drone, and a signal processing module arranged inside the data acquisition box (2); The acoustic array (1) comprises a microphone (11) arranged outside the data acquisition box and connected to the signal processing module, and used for detecting acoustic signals; The signal processing module is used to process the acoustic signal detected by the acoustic array (1); The storage battery is used to supply power to the signal processing module.

2. The drone-borne acoustic detection system according to claim 1, characterized in that: The acoustic array (1) also includes a support rod (12) connecting the microphone and the data acquisition box, which is used to adjust the position of the microphone (11) relative to the data acquisition box by contraction or bending.

3. The UAV-borne acoustic detection system according to claim 2, characterized in that: The acoustic array (1) specifically comprises three microphones (11) located in the same plane, and a single microphone (11) perpendicular to the three microphones (11); among the three microphones (11), the position angles of any two microphones (11) are the same.

4. The drone-borne acoustic detection system according to claim 1, characterized in that: The microphone (11) is provided with a windshield for eliminating the influence of wind noise during use.

5. The drone-borne acoustic detection system according to claim 1, characterized in that: The drone-borne acoustic detection system further comprises a locator arranged on the drone; the locator is used to convert the coordinates of the acoustic signal detected by the acoustic array (1) into the coordinate system of the drone.

6. The UAV-borne acoustic detection system according to claim 1, characterized in that: The signal processing module adopts an ARM and field programmable gate array FPGA combined architecture.

7. The drone-borne acoustic detection system according to claim 1, characterized in that: The unmanned aerial vehicle acoustic detection system further comprises a wireless communication module arranged inside the data acquisition box (2) and used for transmitting the acoustic signal processed by the signal processing module to the outside world.

8. The drone-borne acoustic detection system according to claim 1, characterized in that: The unmanned aerial vehicle acoustic detection system further comprises a clock synchronization module arranged inside the data acquisition box (2) and used for synchronizing the timing of the acoustic signals detected by the acoustic array (1).

9. The drone-borne acoustic detection system according to claim 8, characterized in that: The clock synchronization module has a built-in constant temperature crystal oscillator or a rubidium clock for providing time information; The clock synchronization module is specifically used to receive a time signal from a satellite, and use the time signal to correct the time information provided by the constant temperature crystal oscillator or the rubidium clock.

10. The drone-borne acoustic detection system according to claim 1, characterized in that: The unmanned aerial vehicle-borne acoustic detection system further comprises an inertial combined navigation module arranged inside the data acquisition box (2) and used for positioning and navigating the unmanned aerial vehicle.

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