Unmanned aerial vehicle real-time positioning device and method based on acoustic sensor

Abstract

The invention relates to an unmanned aerial vehicle real-time positioning device based on a sound sensor, which comprises a base, a bracket mounted on the base, three cantilevers mounted on the bracket, and a rotary pickup device mounted at the end parts of the cantilevers, the rotary pickup device comprises a stepping motor mounted at the end parts of the cantilevers, and the stepping motor is connected with a rotary arm; a sound sensor A and a sound sensor B are installed at the two ends of the rotating arm respectively, the rotating pickup device is connected with a signal power line, the signal power line is connected with a sound signal conditioning, collecting and rotating arm controller, and the sound signal conditioning, collecting and rotating arm controller is connected with a computer through a network transmission line. The invention has the beneficial effects that the environment adaptability is high, and the device can work at night and under severe weather such as rain and snow; concealment and non-invasiveness are achieved, and positioning is achieved only through sound signals; the system is low in hardware cost, is easy to deploy and expand, is suitable for the scenes of urban security, airport safety, border patrol and the like, and provides an efficient and flexible low-cost unmanned aerial vehicle monitoring scheme for the fields of intelligent security, traffic management and the like.

Description

Technical Field

[0001] The present invention belongs to the technical field of unmanned aerial vehicle (UAV) position detection and positioning, and in particular relates to a real-time UAV positioning device and positioning method based on an acoustic sensor. Background Art

[0002] With the widespread use of drones, their importance in military reconnaissance, logistics distribution, security patrols, and other fields has become increasingly prominent. However, efficient and accurate detection and positioning of drones in the air still faces many challenges in real-world scenarios. Traditional drone detection technologies rely primarily on visual recognition (such as cameras or laser scanning) or radar detection, but these methods have significant limitations in certain complex environments. For example, the effectiveness of visual technology is significantly reduced in inclement weather (such as rain, snow, fog, and haze) or in low-visibility conditions at night. Radar equipment, on the other hand, can be limited in practical application due to its high cost, large size, or sensitivity to environmental electromagnetic interference.

[0003] The application publication number is CN115586487A, the application publication date is 2023.01.10, and the patent name is an invention patent for a passive detection and positioning system for low-altitude unmanned aerial vehicles. Although its multi-band antenna and multi-channel receiving components can cover a wider frequency range, they also increase the complexity and cost of the antenna design. It is difficult to balance the system complexity and cost, and it has high requirements for application scenarios and poor adaptability.

[0004] The application publication number is CN116972955A, the application publication date is 2023.10.31, and the patent name is an invention patent for a real-time detection and positioning method and system for low-altitude unmanned aerial vehicles. It arranges optical fiber distributed sensors over a large area. Although it has the advantages of wide coverage, strong concealment, anti-electromagnetic interference and high sensitivity, it has the shortcomings of high hardware cost, high technical complexity and difficulty in maintenance. Summary of the Invention

[0005] In order to make up for the deficiencies of the existing technology, the present invention provides a simple, efficient, flexible, low-cost, easy-to-maintain, and wide-coverage UAV real-time positioning device and positioning method based on acoustic sensors.

[0006] The present invention is achieved through the following technical solutions: A real-time positioning device for a drone based on an acoustic sensor comprises a base with a bracket mounted on the base. The device is characterized in that three cantilevers are mounted on the bracket, a rotating sound pickup device is mounted at the end of the cantilever, the rotating sound pickup device comprises a stepper motor mounted at the end of the cantilever, the stepper motor is connected to a rotating arm, an acoustic sensor A and an acoustic sensor B are mounted at both ends of the rotating arm, the rotating sound pickup device is connected to a signal power line, the signal power line is connected to an acoustic signal conditioning and acquisition device and a rotating arm controller, and the acoustic signal conditioning and acquisition device and the rotating arm controller are connected to a computer via a network transmission line.

[0007] Preferably, the three cantilevers have the same length, are perpendicular to each other in pairs, and intersect at one point at their centers.

[0008] The acoustic signal conditioning and acquisition and rotating arm controller consists of a microcontroller, a power supply, a bandpass filter circuit, a signal amplification circuit, an analog-to-digital conversion circuit, a stepper motor drive circuit, a stepper motor encoder and a network protocol chip, wherein: A microcontroller is used to receive and process sound signal data, send instructions to control the stepper motor drive circuit, and read the motor position information fed back by the stepper motor encoder; Bandpass filter circuit, used to filter the input original sound signal to remove noise and irrelevant frequency signals; A signal amplifying circuit, used to amplify the filtered sound signal; Analog-to-digital conversion circuit, used to convert sound signals into digital signals; The stepper motor drive circuit is used to receive instructions from the microcontroller to drive the stepper motor to realize the rotation control of the rotating arm; The stepper motor encoder is used to monitor the rotation angle and position information of the stepper motor in real time and feed it back to the microcontroller; The network protocol chip is used to encode and package the signals processed by the microcontroller according to the network protocol and send them to the computer through the network transmission line.

[0009] A real-time positioning method for a UAV based on an acoustic sensor is characterized by comprising the following steps: (1) With the intersection of the three cantilevers as the origin, the three cantilevers are on the XYZ axis, and a Cartesian coordinate system XYZ is established. The target is set at P(x, y, z). The rotating pickup devices on the three cantilevers are XA, XB, YA, YB, ZA, and ZB respectively. (2) The sound sensor A on XA is recorded as XA-A, the sound sensor B on XA is recorded as XA-B, the sound sensor A on XB is recorded as XB-A, the sound sensor B on XB is recorded as XB-B, the sound sensor A on YA is recorded as YA-A, the sound sensor B on YA is recorded as YA-B, the sound sensor B on YB is recorded as YB-A, the sound sensor B on YB is recorded as YB-B, the sound sensor A on ZA is recorded as ZA-A, the sound sensor B on ZA is recorded as ZA-B, the sound sensor A on ZB is recorded as ZB-A, the sound sensor B on ZB is recorded as ZB-B, (3) Set the initial position XA-A to M A1 Point, coordinates are (x MA1 ,y MA1 ,z MA1 ), at this time the initial angle of the stepper motor is δ XA1 , M A1 The distance from the point to the target P(x,y,z) is: ; (4) Establish a Cartesian coordinate system X with the midpoint of XA-A and XA-B as the origin XA Y XA Z XA , where the coordinate system X XA Y XA Z XA It is obtained by translating the coordinate system XYZ along the positive direction of the X axis by a distance W, where W is the distance from the midpoint of XA-A and XA-B to the origin of the coordinate system XYZ; M A1 In coordinate system X XA Y XA Z XA In Chinese , where the distance between XA-A and XA-B is 2L, and the distance between XA-A and XA-B and the X axis is L. According to the coordinate translation formula, M A1 The coordinates on the XYZ coordinate system are ; (5) XA rotation angle θ XA1 After that, XA-A arrives at N A1 Point, N A1 The coordinates of the point are (x NA1, y NA1, z NA1 ), N A1 The distance from the point to the target P(x,y,z) is: , where N A1 The coordinates are ; (6) XA rotation angle ρXA1 After that, XA-A arrives at K A1 Point, K A1 The coordinates of the point are (x KA1, y KA1, z KA1 ), K A1 The distance from the point to the target P(x,y,z) is: , where K A1 The coordinates are ; (7) The rotating pickup device rotates rapidly, the target position is fixed, and the speed of sound propagation in the air is V 声 , the frequency of the stepper motor drive pulse is f 步 , the step angle is γ 步 , The following formula is obtained: ; ;

[0010] The joint solution is P(x,y,z), denoted as P XA (x pxA ,y pxA ,z pxA ); (8) Repeat the above steps to obtain P(x, y, z) of the other five rotating pickup devices, which are denoted as P XB (x pxB ,y pxB ,z pxB )、P YA (x pYA ,y pYA ,z pYA )、P YB (x pYB ,y pYB ,z pYB )、P ZA (x pZA ,y pZA ,z pZA )、P ZB (x pZB ,y pZB ,z pZB ); (9) Take the average value of the above six coordinate points, then ; ; .

[0011] The beneficial effects of the present invention are: by collecting drone sound signals through a rotating sound sensor array, utilizing characteristics such as sound propagation time difference, sound intensity difference and relative position changes of each sound sensor, combined with adaptive signal processing algorithms, multi-sensor fusion and environmental noise suppression algorithms, high-precision positioning is achieved without relying on vision, laser and drone communication interaction.

[0012] As a result, its effects are significant: first, it has strong environmental adaptability and can work at night, in rainy and snowy weather, breaking through the environmental limitations of visual and radar technologies; second, it is concealed and non-invasive, and can be located only by sound signals, without the need to interfere with or mark the drone; third, the hardware cost is low and easy to deploy and expand, making it suitable for scenarios such as urban security, airport security, and border patrols, providing an efficient, flexible, and low-cost drone monitoring solution for smart security, traffic management, and other fields. BRIEF DESCRIPTION OF THE DRAWINGS

[0013] The present invention will be further described below with reference to the accompanying drawings.

[0014] Attachment Figure 1 It is a structural schematic diagram of the present invention; Attachment Figure 2 It is a structural schematic diagram of the rotary sound pickup device of the present invention; Attachment Figure 3 This is a block diagram of the internal structure of the acoustic signal conditioning, acquisition and rotating arm controller of the present invention; Attachment Figure 4 is a diagram of the labels of the sound sensors of the present invention; Attachment Figure 5 This is a schematic diagram of target position calculation of the present invention; In the figure, 1 is the base, 2 is the bracket, 3 is the cantilever, 4 is the rotating sound pickup device, 5 is the stepping motor, 6 is the rotating arm, 7 is the sound sensor A, 8 is the sound sensor B, 9 is the signal power line, 10 is the sound signal conditioning acquisition and rotating arm controller, 11 is the network transmission line, and 12 is the computer. DETAILED DESCRIPTION

[0015] The accompanying drawings illustrate a specific embodiment of the present invention. This embodiment includes a base 1, a bracket 2 mounted on the base 1, three cantilevers 3 mounted on the bracket 2, and a rotating sound pickup device 4 mounted at the end of each cantilever 3. The rotating sound pickup device 4 includes a stepper motor 5 mounted at the end of the cantilever 3, which is connected to a rotating arm 6. A sound sensor A7 and a sound sensor B8 are mounted at each end of the rotating arm 6. The rotating sound pickup device 4 is connected to a signal power line 9, which is connected to an acoustic signal conditioning and acquisition system and rotating arm controller 10. The acoustic signal conditioning and acquisition system and rotating arm controller 10 is connected to a computer 12 via a network transmission line 11. The three cantilevers 3 are of equal length, perpendicular to each other, and intersecting at their centers.

[0016] The real-time positioning device for drones based on acoustic sensors of the present invention is adopted. The base 1 serves as the foundation of the device and is used to fix and support the entire device. The bracket 2 is vertically installed on the base 1 to provide support for the upper structure. The upper structure has three cantilevers 3 of equal length and perpendicular to each other. The centers of the three cantilevers 3 intersect at one point.

[0017] The rotating sound pickup device 4 includes a stepper motor 5, a rotating arm 6, a sound sensor A7 and a sound sensor B8. The stepper motor 5 provides power and drives the rotating arm 6 to rotate after startup. Sound sensors A7 and B8 are installed at both ends of each rotating arm 6. A total of 6 rotating arms form a sound collection array for capturing the sound of the drone.

[0018] Stepper motor 5 drives rotating arm 6, which in turn rotates the sound sensor to collect sound signals from aerial sound sources. The signals collected by the sound sensor are transmitted via signal power cable 9 to the sound signal conditioning and acquisition and rotating arm controller 10. The sound signals are amplified, noise-reduced, and packaged before being transmitted via network transmission line 11 to computer 12, which analyzes the drone's position.

[0019] The acoustic signal conditioning, acquisition and rotating arm controller 10 consists of a microcontroller, a power supply, a bandpass filter circuit, a signal amplification circuit, an analog-to-digital conversion circuit, a stepper motor drive circuit, a stepper motor encoder, and a network protocol chip; each module is powered by a power supply, and signal processing and control are realized with the microcontroller as the core.

[0020] As the core of the circuit, the microcontroller is responsible for coordinating and controlling the work of each module, receiving the processed sound signal data, sending instructions to control the stepper motor drive circuit to control the rotation of the stepper motor 5, and reading the motor position information and motor rotation status feedback from the stepper motor encoder to realize the overall logical control of the system.

[0021] The bandpass filter circuit retains useful frequencies, filters out noise, and filters the input original sound signal, allowing only signals within a specific frequency range to pass through, filtering out noise and irrelevant frequency signals, and improving signal purity.

[0022] The signal amplification circuit amplifies the filtered sound signal to enhance the signal strength, ensuring that the subsequent analog-to-digital conversion circuit can accurately identify and convert the signal.

[0023] The analog-to-digital conversion circuit converts the sound signal into a digital signal, which is convenient for the microcontroller to perform digital processing and analysis.

[0024] The stepper motor driving circuit receives instructions from the microcontroller to drive the stepper motor 5 to work, thereby realizing the rotation control of the rotating arm 6.

[0025] The stepper motor encoder monitors the rotation angle, position and other information of the stepper motor 5 in real time, and feeds back to the microcontroller to provide data support for precise control of the stepper motor 5.

[0026] The network protocol chip encodes and packages the signal processed by the microcontroller according to the network protocol, and sends it to the computer 12 through the network transmission line to realize remote transmission of the signal.

[0027] The real-time positioning method of the UAV based on the acoustic sensor of the present invention is adopted. The intersection of the three cantilevers 3 is taken as the origin. The three cantilevers are on the XYZ axis. A Cartesian rectangular coordinate system XYZ is established. It is assumed that the target is located at P(x, y, z). The sound pickup structures on the three cantilevers are XA, XB, YA, YB, ZA, and ZB respectively.

[0028] XA and XB are perpendicular to the X-axis and symmetrical about the origin. The midpoints of XA and XB are on the X-axis. The sound sensors on the sound pickup structure XA are XA-A and XA-B respectively, and the sound sensors on the sound pickup structure XB are XB-A and XB-B respectively; YA and YB are perpendicular to the Y-axis and symmetrical about the origin. The midpoints of YA and YB are on the Y-axis. The sound sensors on the sound pickup structure YA are YA-A and YA-B respectively, and the sound sensors on the sound pickup structure YB are YB-A and YB-B respectively; ZA and ZB are perpendicular to the Z-axis and symmetrical about the origin. The midpoints of ZA and ZB are on the Z-axis. The sound sensors on the sound pickup structure ZA are ZA-A and ZA-B respectively, and the sound sensors on the sound pickup structure ZB are ZB-A and ZB-B respectively.

[0029] Taking the sound pickup structures XA and XB on the X-axis as an example to calculate the specific position of the target P(x, y, z), the calculation method of the sound sensor XA-A on the sound pickup structure XA and the target P(x, y, z) is explained as an example.

[0030] Assume that the initial position of the sound sensor XA-A is M A1 Point, M A1 Point is a known point with coordinates (x MA1 ,y MA1 ,z MA1 ), at this time the initial angle of stepper motor 5 is δ XA1 , M A1 The distance from the point to the target P(x,y,z) is: .

[0031] M A1 (x MA1 ,y MA1 ,z MA1 ) is calculated as follows: First, a Cartesian coordinate system X is established with the midpoint of sensors XA-A and XA-B on the pickup structure XA as the origin. XA Y XA Z XA , where the coordinate system X XA Y XA Z XA Obtained by translating the coordinate system XYZ along the X-axis by a distance W (in the positive direction of the X-axis), where W is the distance from the midpoint of sensors XA-A and XA-B to the origin of the coordinate system XYZ. M A1 In coordinate system X XA Y XA Z XA Zhongke , where the distance between XA-A and XA-B is 2L, and the distance between XA-A and XA-B and the X axis is L. According to the coordinate translation formula, M A1 The coordinates on the XYZ coordinate system are .

[0032] Pickup structure XA rotation angle θ XA1 After that, the sound sensor XA-A reaches N A1 Point, N A1 The coordinates of the point are (x NA1, y NA1, z NA1 ), N A1 The distance from the point to the target P(x,y,z) is: , where N A1 The coordinates are .

[0033] Pickup structure XA rotation angle ρ XA1 After that, the sound sensor XA-A reaches K A1 Point, K A1 The coordinates of the point are (x KA1 ,y KA1 ,z KA1 ), K A1 The distance from the point to the target P(x,y,z) is: , where K A1 The coordinates are .

[0034] When the sound pickup structure rotates rapidly, the position of the target object can be considered to be fixed, and the speed of sound propagation in the air is V 声 , the frequency of the stepper motor 5 driving pulse is f 步 , the step angle is γ 步 , ; ; ;

[0035] Based on the above equations, the three equations contain three unknowns, and the joint solution can obtain P(x, y, z), denoted as P XA (x pxA ,y pxA ,z pxA ).

[0036] According to the data information collected by the other five sound pickup structures, based on the same calculation method, five P(x,y,z) can be obtained, which are P XB (x pxB ,y pxB ,z pxB )、P YA (x pYA ,y pYA ,z pYA )、P YB (x pYB ,y pYB ,z pYB )、P ZA (x pZA ,y pZA ,z pZA )、P ZB (x pZB ,y pZB ,z pZB ).

[0037] To eliminate the error, take the average of the six calculation results as the coordinate value of P(x,y,z), and get , , .

Claims

1. A real-time positioning device for a drone based on an acoustic sensor, comprising a base (1) with a bracket (2) mounted on the base (1), characterized in that: A cantilever (3) is mounted on the bracket (2), a rotating sound pickup device (4) is mounted at the end of the cantilever (3), the rotating sound pickup device (4) comprises a stepper motor (5) mounted at the end of the cantilever (3), the stepper motor (5) is connected to a rotating arm (6), a sound sensor A (7) and a sound sensor B (8) are mounted at both ends of the rotating arm (6), the rotating sound pickup device (4) is connected to a signal power line (9), the signal power line (9) is connected to an acoustic signal conditioning and acquisition and rotating arm controller (10), and the acoustic signal conditioning and acquisition and rotating arm controller (10) are connected to a computer (12) via a network transmission line (11).

2. The real-time positioning device for drones based on acoustic sensors according to claim 1 is characterized by: There are three cantilevers (3), the three cantilevers (3) are equal in length, the three cantilevers (3) are perpendicular to each other, and the centers of the three cantilevers (3) intersect at one point.

3. The real-time positioning device for drones based on acoustic sensors according to claim 1 is characterized in that: The acoustic signal conditioning acquisition and rotating arm controller (10) is composed of a microcontroller, a power supply, a bandpass filter circuit, a signal amplification circuit, an analog-to-digital conversion circuit, a stepper motor drive circuit, a stepper motor encoder and a network protocol chip, wherein: A microcontroller is used to receive and process sound signal data, send instructions to control the stepper motor drive circuit, and read the position information of the stepper motor (5) fed back by the stepper motor encoder; Bandpass filter circuit, used to filter the input original sound signal to remove noise and irrelevant frequency signals; A signal amplifying circuit, used to amplify the filtered sound signal; Analog-to-digital conversion circuit, used to convert sound signals into digital signals; A stepper motor drive circuit is used to receive instructions from the microcontroller to drive the stepper motor (5) to work and realize the rotation control of the rotating arm (6); A stepper motor encoder is used to monitor the rotation angle and position information of the stepper motor (5) in real time and feed it back to the microcontroller; The network protocol chip is used to encode and package the signal processed by the microcontroller according to the network protocol and send it to the computer (12) through the network transmission line (11).

4. The positioning method of the UAV real-time positioning device based on an acoustic sensor according to any one of claims 1 to 3, characterized in that: The following steps are involved: (1) With the intersection of the three cantilevers (3) as the origin, the three cantilevers (3) are on the XYZ axis, and a Cartesian rectangular coordinate system XYZ is established. The target is set at P (x, y, z), and the rotating pickup devices (4) on the three cantilevers (3) are XA, XB, YA, YB, ZA, and ZB respectively; (2) The sound sensor A (7) on XA is recorded as XA-A, the sound sensor B (8) on XA is recorded as XA-B, the sound sensor A (7) on XB is recorded as XB-A, the sound sensor B (8) on XB is recorded as XB-B, the sound sensor A (7) on YA is recorded as YA-A, the sound sensor B (8) on YA is recorded as YA-B, the sound sensor A (7) on YB is recorded as YB-A, the sound sensor B (8) on YB is recorded as YB-B, the sound sensor A (7) on ZA is recorded as ZA-A, the sound sensor B (8) on ZA is recorded as ZA-B, the sound sensor A (7) on ZB is recorded as ZB-A, and the sound sensor B (8) on ZB is recorded as ZB-B; (3) Set the initial position XA-A to M A1 Point, coordinates are (x MA1 ,y MA1 ,z MA1 ), at this time the initial angle of the stepper motor (5) is δ XA1 , M A1 The distance from the point to the target P(x,y,z) is: ； (4) Establish a Cartesian coordinate system X with the midpoint of XA-A and XA-B as the origin XA Y XA Z XA , where the coordinate system X XA Y XA Z XA It is obtained by translating the coordinate system XYZ along the positive direction of the X axis by a distance W, where W is the distance from the midpoint of XA-A and XA-B to the origin of the coordinate system XYZ; M A1 In coordinate system X XA Y XA Z XA In Chinese , where the distance between XA-A and XA-B is 2L, and the distance between XA-A and XA-B and the X axis is L. According to the coordinate translation formula, M A1 The coordinates on the XYZ coordinate system are ; (5) XA rotation angle θ XA1 After that, XA-A arrives at N A1 Point, N A1 The coordinates of the point are (x NA1, y NA1, z NA1 ), N A1 The distance from the point to the target P(x,y,z) is: , where N A1 The coordinates are ; (6) XA rotation angle ρ XA1 After that, XA-A arrives at K A1 Point, K A1 The coordinates of the point are (x KA1, y KA1, z KA1 ), K A1 The distance from the point to the target P(x,y,z) is: ， where K A1 The coordinates are ; (7) The rotating sound pickup device (4) rotates rapidly, the target position is fixed, and the speed of sound propagation in the air is V 声 , the frequency of the stepper motor (5) driving pulse is f 步 , the step angle is γ 步 , The following formula is obtained: ； ； ； The joint solution is P(x,y,z), denoted as P XA (x pxA ,y pxA ,z pxA ); (8) Repeat the above steps to obtain P(x, y, z) of the other five rotating pickup devices (4), which are respectively denoted as P XB (x pxB ,y pxB ,z pxB )、P YA (x pYA ,y pYA ,z pYA )、P YB (x pYB ,y pYB ,z pYB )、P ZA (x pZA ,y pZA ,z pZA )、P ZB (x pZB ,y pZB ,z pZB ); (9) Take the average value of the above six coordinate points, then ； ； 。

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