Unmanned aerial vehicle positioning system and method based on bat-like ultrasonic wave transmission and reception

Abstract

The application discloses a kind of unmanned plane positioning system and method based on bat ultrasonic wave transceiving, including: unmanned plane body and controller, the base is equipped on the unmanned plane body, the base is equipped with respectively with the ultrasonic wave transmitting device, ultrasonic wave receiving device and antenna connected with controller;Ultrasonic wave transmitting device and ultrasonic wave receiving device are oppositely arranged;The ultrasonic wave receiving device includes: for simulating the characteristics of outer ear of bat analog outer ear, with signal receiver for receiving the physical signal generated when analog outer ear is deformed, for supporting and adjusting the position and angle of analog outer ear bionic movement device;The controller can control bionic movement device movement, to change the position and angle of analog outer ear.The application can adjust the spatial position and inclination angle of analog outer ear according to actual needs, and the ear and head movement of bat when receiving acoustic signal is well simulated.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of unmanned aerial vehicle positioning, and particularly relates to an unmanned aerial vehicle positioning system and method based on bat-like ultrasonic wave transmission and reception. BACKGROUND

[0002] The statements in this section merely provide background information related to the present application and do not necessarily constitute the prior art.

[0003] At present, common methods of indoor positioning of unmanned aerial vehicles include: visual positioning technology, laser radar-based positioning technology and UWB indoor positioning technology. Although the visual positioning technology has high positioning accuracy, it is susceptible to light interference and has low real-time performance, and the laser radar-based positioning technology is susceptible to environmental influences and requires expensive instruments, and the UWB indoor positioning technology also has the disadvantages of low real-time performance and complex algorithm.

[0004] At present, the research on the reception of ultrasonic waves by animal external ears is still in the mechanism research stage, and the artificial external ear receiving device is also very imperfect and cannot achieve the effect of sound wave reception by animals; therefore, the research on combining analog bionic technology with unmanned aerial vehicle positioning technology is rare in the prior art. SUMMARY

[0005] In order to solve the above problems, the present application proposes an unmanned aerial vehicle positioning system and method based on bat-like ultrasonic wave transmission and reception, which has the advantages of being unaffected by light and being capable of actively transmitting and receiving ultrasonic waves, and can greatly improve the indoor positioning efficiency and accuracy of unmanned aerial vehicles by combining with the strong maneuverability of unmanned aerial vehicles.

[0006] In some embodiments, the following technical solutions are adopted:

[0007] An unmanned aerial vehicle positioning system based on bat-like ultrasonic wave transmission and reception comprises: an unmanned aerial vehicle body and a controller, a base is arranged on the unmanned aerial vehicle body, and an ultrasonic wave transmitting device, an ultrasonic wave receiving device and an antenna are arranged on the base and connected with the controller respectively.

[0008] The ultrasonic wave transmitting device and the ultrasonic wave receiving device are arranged oppositely; the ultrasonic wave receiving device comprises: an analog external ear for simulating the characteristics of the external ear of a bat, a signal receiver connected with the analog external ear for receiving physical signals generated when the analog external ear deforms, and a bionic motion device for supporting and adjusting the position and angle of the analog external ear; the controller can control the motion of the bionic motion device to change the position and angle of the analog external ear.

[0009] In other embodiments, the following technical solutions are adopted:

[0010] A kind of unmanned plane positioning method based on bat ultrasonic wave transceiver, comprising:

[0011] Two spatial rectangular coordinate systems are respectively established with the centroid of two simulated outer ears as origin;

[0012] According to the received controller instruction, control bionic motion device motion, to change the position and angle of simulated outer ear;

[0013] The digital signal transmitted by unmanned plane is modulated into voltage signal, and after voltage signal is converted into ultrasonic wave signal, it is transmitted;

[0014] Ultrasonic wave signal generates echo signal after encountering obstacle, and the echo signal can be received by simulated outer ear, and make the simulated outer ear produce deformation;

[0015] The deformation is converted into digital signal and delivered to controller, and controller calculates based on the digital signal, obtains the position of obstacle relative to unmanned plane, realizes indoor positioning and obstacle avoidance of unmanned plane;

[0016] Wherein, the obstacle includes wall and other objects capable of generating echo signal outside wall, and by dynamic ultrasonic positioning algorithm, the position information of unmanned plane relative to wall can realize the positioning of unmanned plane;By dynamic ultrasonic positioning algorithm, the distance of unmanned plane relative to other objects can realize the obstacle avoidance of unmanned plane.

[0017] Further, controller calculates the frequency characteristics of echo signal based on the digital signal, to judge whether the echo signal comes from indoor wall or other objects;

[0018] Respectively, echo signal is subjected to matching filtering in distance direction and azimuth direction, to obtain the distance of corresponding obstacle relative to origin, and then obtain the value of the obstacle on X, Y, Z axis in two spatial rectangular coordinate systems;

[0019] When distance direction matching is carried out, whether the received echo signal is error term generated by distance migration is judged by the difference of azimuth angle.

[0020] Compared with prior art, the beneficial effects of the present application are:

[0021] (1) The application can make the simulated external ear have the characteristics of controlling the beam direction and frequency sweeping by setting the bionic external ear and bionic external ear underflap; the characteristic of controlling the beam direction refers to the characteristic that the simulated external ear can generate a series of beams that constantly move with the change of frequency within a frequency period of the received ultrasonic wave without moving its ear, which greatly improves the efficiency of the simulated external ear in obtaining ultrasonic information. The frequency sweeping refers to a frequency line relationship when the bat ear receives a frequency modulation signal in the far field, and the frequency spectrum curve is a straight line, that is, the frequency of the bat in the far field is unfolded from low to high, and the angle energy corresponding to different frequencies changes, which can simplify and eliminate the errors in the Y-axis and Z-axis directions, thereby improving the accuracy and operation speed of the ultrasonic dynamic positioning algorithm.

[0022] (2) The application can adjust the spatial position and inclination angle of the simulated external ear according to actual needs by setting the ear movement platform and head movement platform, which well simulates the ear and head movement of the bat when receiving sound wave signals, making the system more flexible and practical.

[0023] (3) The application can make the positioning information more accurate and real-time through the filtering, framing and windowing processing of the echo signal by the controller and the dynamic ultrasonic positioning algorithm.

[0024] Other features and advantages of the present application will be partially given in the following description, partially will become obvious from the following description, or will be understood by the practice of the present application. BRIEF DESCRIPTION OF DRAWINGS

[0025] Figure 1 The figure is a schematic diagram of the overall structure of the unmanned aerial vehicle positioning system based on the bionic bat ultrasonic wave transceiver in the embodiment of the application;

[0026] Figure 2 The figure is a schematic diagram of the structure of the ultrasonic wave transmitting device and the ultrasonic wave receiving device in the embodiment of the application;

[0027] Among them, 1. ultrasonic wave receiving device, 2. ultrasonic wave transmitting device, 3. controller, 4. base, 5. antenna, 6. signal receiver, 7. simulated external ear, 8. ear connecting rod, 9. head connecting rod, 10. ear movement platform, 11. head movement platform, 12. signal modulation device, 13. ultrasonic wave transmitter. DETAILED DESCRIPTION

[0028] It should be pointed out that the following detailed description is exemplary and is intended to provide further description of the present application. Unless otherwise specified, all technical and scientific terms used in the present application have the same meaning as generally understood by those skilled in the art to which the present application belongs.

[0029] It should be noted that the terminology used herein is for the purpose of describing particular embodiments only and is not intended to limit the exemplary embodiments according to this application. As used herein, the singular form is intended to include the plural form as well, unless the context clearly indicates otherwise. Furthermore, it should be understood that when the terms "comprising" and / or "including" are used in this specification, they indicate the presence of features, steps, operations, devices, components, and / or combinations thereof.

[0030] Example 1

[0031] In one or more embodiments, a drone positioning system based on bat-inspired ultrasonic transceiver is disclosed, with reference to... Figure 1 Specifically, it includes: the drone body and the controller 3. The drone body has a base 4 at its bottom. The base 4 has an ultrasonic transmitter 2, an ultrasonic receiver 1 and an antenna 5 that are respectively connected to the controller 3. The controller 3 can be an internal controller of the drone or a separately set controller that communicates with the drone.

[0032] In this embodiment, combined with Figure 2 The ultrasonic transmitter 2 and the ultrasonic receiver 1 are arranged opposite to each other; the antenna 5 is used to transmit and / or receive electromagnetic wave signals; wherein,

[0033] The ultrasonic transmitting device 2 includes: an ultrasonic transmitter 13 for transmitting ultrasonic waves and a signal modulation device 12 for converting digital signals from the controller 3 into voltage signals.

[0034] The digital signal emitted by the UAV is modulated into a voltage signal by the signal modulation device 12, and the ultrasonic transmitter 13 converts the voltage signal into an ultrasonic signal and then emits it. The ultrasonic signal generates an echo signal when it encounters an obstacle.

[0035] In this embodiment, the ultrasonic transmitter 13 emits ultrasonic signals with consistent intensity and frequency in all directions; a piezoelectric ceramic transducer can be used.

[0036] The ultrasonic receiving device 1 includes: a simulated outer ear 7 for simulating the characteristics of a bat's outer ear; a signal receiver 6 connected to the simulated outer ear 7 for receiving physical signals generated when the simulated outer ear 7 deforms; and a bionic motion device for supporting and adjusting the position and angle of the simulated outer ear 7. The controller 3 is capable of controlling the movement of the bionic motion device, thereby changing the position and angle of the simulated outer ear 7.

[0037] After receiving the echo signal, the simulated outer ear 7 deforms. The signal receiver 6 converts the physical information represented by the deformation into a digital signal and transmits it to the controller 3. The controller 3 calculates the position of the drone relative to the obstacle on the X, Y, and Z axes based on the received digital signal, thereby realizing the indoor positioning and obstacle avoidance of the drone.

[0038] Wherein, the obstacle refers to the object which can produce echo signal to the contacted ultrasonic signal, including wall and other objects, the echo signal of different obstacles has different frequency and amplitude characteristics, the controller 3 only needs to record the frequency characteristics of the echo signal produced by the wall to distinguish the wall from other obstacles. By dynamic ultrasonic positioning algorithm, the distance and direction of each obstacle relative to the position of the unmanned aerial vehicle are known, and the position information between the unmanned aerial vehicle and the indoor wall is the indoor position of the unmanned aerial vehicle, and the position information between the unmanned aerial vehicle and other obstacles is used to help the unmanned aerial vehicle to avoid obstacles.

[0039] Specifically, the simulated outer ear 7 includes a bionic outer ear and a bionic outer ear under flap, the bionic outer ear produces physical deformation when receiving echo signals, and plays a role in simulating the outer ear of a bat; the bionic outer ear under flap is arranged inside the bionic outer ear, so that the receiving echo process has the characteristics of being able to control the direction of the beam and the frequency sweeping property; the bionic outer ear and the bionic outer ear under flap both need to be made of flexible materials, such as silicone.

[0040] In this embodiment, the bionic motion device specifically includes: a head motion platform 11, an ear motion platform 10, an ear connecting rod 8 and a head connecting rod 9; the simulated outer ear 7 and the ear motion platform 10 are arranged on the head motion platform 11, one end of the ear connecting rod 8 is connected with the simulated outer ear 7, and the other end is connected with the ear motion platform 10, one end of the head connecting rod 9 is connected with the simulated outer ear 7, and the other end is connected with the head motion platform 11.

[0041] Wherein, the head motion platform 11 includes a first base, a first connecting rod and a first motion platform arranged on the base 4, three connecting points are respectively arranged on the first base and the first motion platform, the connecting points on the first base and the first motion platform are connected through the first connecting rod, and the first connecting rod is respectively hinged with the first base and the first motion platform through a hooke joint or a spherical hinge; each first connecting rod can be driven to stretch and retract by a telescopic electric cylinder driven by a servo motor, each electric cylinder can independently make stretching and retracting motion in space, by controlling the stretching and retracting amount of the six electric cylinders, the first motion platform can complete six-degree-of-freedom motion in space, so as to realize the change of the position and posture of the first motion platform, and the base always remains stationary.

[0042] The ear movement platform 10 comprises a second base, a second connecting rod and a second movement platform arranged on the head movement platform 11; similar to the head movement platform 11, the second base and the second movement platform are respectively provided with three connecting points, and the connecting points on the second base and the second movement platform are connected through the second connecting rod, and the second connecting rod is hinged with the second base and the second movement platform through a hooke joint or a spherical hinge; each second connecting rod can be driven to stretch and retract through a telescopic electric cylinder driven by a servo motor, so that the second movement platform can realize six-degree-of-freedom movement.

[0043] The ear connecting rod 8 and the head connecting rod 9 are both hollow metal pipes, one end of the ear connecting rod 8 is fixed to the six-degree-of-freedom platform surface of the ear movement platform 10, and the other end is connected with the simulated outer ear 7 through a hinge; one end of the head connecting rod 9 is fixed to the six-degree-of-freedom platform surface of the head movement platform 11, and the other end is connected with the simulated outer ear 7 through a hinge. Since the head movement platform 11 and the ear movement platform 10 can both move in space with six degrees of freedom, the movement of the simulated outer ear 7 can be driven through the ear connecting rod 8 and the head connecting rod 9, so as to change the spatial position and inclination angle of the simulated outer ear 7.

[0044] The ear connecting rod 8 is connected with the surface of the six-degree-of-freedom ear movement platform 10 to realize small-range movement of the simulated outer ear 7; the head connecting rod 9 is connected with the surface of the six-degree-of-freedom head movement platform 11, and the simulated outer ear 7 and the ear movement platform 10 are both fixed on the surface of the six-degree-of-freedom head movement platform 11, which can simulate the head movement of a bat to realize large-range movement of the simulated outer ear 7.

[0045] The six-degree-of-freedom head movement platform 11 and the six-degree-of-freedom ear movement platform 10 are both connected with the controller 3, and the controller 3 can send control instructions to control the movement of the six-degree-of-freedom ear movement platform 10 and / or the six-degree-of-freedom ear movement platform 10, so as to change the spatial position and inclination angle of the simulated outer ear 7.

[0046] Two signal receivers 6 are mounted on the surface of the head movement platform 11, the signal receivers 6 are provided with sliding bearings at the ends, and the roots of the two simulated outer ears 7 are respectively connected with the sliding bearings of the two signal receivers 6. The signal receivers 6 are used to receive physical signals generated when the simulated outer ear 7 deforms, and convert the physical signals into digital signals and transmit the digital signals to the controller 3.

[0047] The controller of the embodiment can adopt an Arduino control mainboard and an embedded open source operating system to improve the openness and secondary development of the system, and realize functions such as platform movement posture control, real-time parameter acquisition and communication control.

[0048] Embodiment two

[0049] In one or more embodiments, a drone positioning method based on bat-like ultrasonic transceiving is disclosed, specifically including the following processes:

[0050] (1) Set the current flight direction of the drone as the positive direction of the X axis, the left and right directions of the flight direction of the drone as the Y axis, and the vertical up and down direction of the flight direction of the drone as the Z axis. Two X, Y, Z space rectangular coordinate systems are established with the centers of the two simulated outer ears 7 as the origins. Since the positional relationship of the two simulated outer ears 7 is known, the positional relationship of the two coordinate systems is also known.

[0051] (2) Control the bionic motion device to move according to the received controller 3 instructions, thereby changing the position and angle of the simulated outer ear 7;

[0052] Specifically, the actions of the six-degree-of-freedom head motion platform 11 and the six-degree-of-freedom ear motion platform 10 are controlled by the controller 3, thereby driving the simulated outer ear 7 to move, so as to change the spatial position and inclination angle of the simulated outer ear 7.

[0053] (3) Modulate the digital signal transmitted by the drone into a voltage signal, and convert the voltage signal into an ultrasonic signal for transmission after conversion;

[0054] The signal modulation device 12 modulates the digital signal transmitted by the drone into a voltage signal, and the ultrasonic transmitter 13 converts the voltage signal into an ultrasonic signal for transmission after conversion.

[0055] (4) The ultrasonic signal generates a return signal after encountering an obstacle, and the return signal can be received by the simulated outer ear 7 and cause the simulated outer ear 7 to deform;

[0056] (5) The deformation is converted into a digital signal and transmitted to the controller 3, and the controller 3 performs calculation based on the digital signal to obtain the position of the drone relative to the obstacle, thereby realizing indoor positioning and obstacle avoidance of the drone.

[0057] Wherein, the obstacle refers to an object that can generate a return signal to the contacted ultrasonic signal, including walls and other objects, and the return signals of different obstacles have different frequency and amplitude characteristics. The controller 3 only needs to record the frequency characteristics of the return signal generated by the wall to distinguish the wall from other obstacles. According to the dynamic ultrasonic positioning algorithm, the distance and direction of each obstacle relative to the position of the drone are known, and the position information between the drone and the indoor wall is the indoor position of the drone, and the position information between the drone and other obstacles is used to help the drone to avoid obstacles.

[0058] In this embodiment, the signal receiver 6 converts the physical information represented by the deformation into a digital signal and transmits it to the controller 3, which selects a FIR filter and a Kaiser window function to filter, frame and window the digital signal respectively.

[0059] The controller 3 calculates the processed echo signal by a dynamic ultrasonic positioning algorithm to obtain the position of the UAV relative to the indoor walls and other obstacles in the X, Y and Z axes; the specific process is as follows:

[0060] The control first determines whether the echo signal is from the indoor walls or other obstacles by the frequency characteristics of the echo signal generated by the walls stored in the storage module.

[0061] The controller 3 performs range matching filtering on the echo signal, calculates the azimuth angle Ψ by the Doppler shift, through the formula Ψ = arcos (λΩ / 2V), wherein the range direction refers to the direction perpendicular to the flight direction of the UAV, Ω is the Doppler shift, and V is the vehicle speed; the distance R = c.τ / 2, c is the speed of light, and τ is a constant; and the position of the obstacle in the X axis is RcosΨ.

[0062] The controller 3 performs azimuth matching filtering on the echo signal, and the length L of the distance component of the obstacle from the origin in the range direction can be obtained by the size of the frequency shift. Since the position relationship between the two coordinate systems and the length L of the distance component of the obstacle from the origin in the two coordinate systems are known, the values of the obstacle in the Y and Z axes of the two spatial rectangular coordinate systems can be obtained by solving the equation set or other algorithms.

[0063] The equation set is: L^2 = Y^2 + Z^2, L^2 = (Y+a)^2 + (Z+b)^2

[0064] In the formula, Y and Z are the values of the obstacle in the Y and Z axes of one coordinate system (denoted as coordinate system 1). Since the position relationship between the two coordinate systems is known, the values of the obstacle in the Y and Z axes of the other coordinate system converted to the coordinate system 1 can be represented by Y+a and Z+b respectively, and a and b are known constants.

[0065] In this embodiment, when the controller 3 performs range matching filtering on the echo signal, it first matches the obtained echo signal with the frequency response curves of each angle to obtain the corresponding azimuth angle Ψ1; then it calculates Ψ2 by the formula Ψ2 = arccos (λΩ / V). As long as |Ψ1-Ψ2| exceeds 5° in one of the two X, Y and Z axis spatial rectangular coordinate systems, it is determined that the received echo signal is an error term caused by distance migration, and then this time is regarded as a no-echo state, and the position of the obstacle is not calculated, thereby eliminating the error caused by distance migration.

[0066] The final controller 3 sends the obtained positioning information to a control center on the ground in the form of electromagnetic wave signals via the antenna 5.

[0067] The above description is only a specific embodiment of the present application in conjunction with the drawings, and is not intended to limit the scope of protection of the present application. Those skilled in the art should understand that various modifications or variations can be made on the basis of the technical solutions of the present application without creative labor, and still fall within the scope of protection of the present application.

Claims

1. A drone positioning system based on bat-inspired ultrasonic transceiver, characterized in that, include: The unmanned aerial vehicle (UAV) includes a base on its main body, and an ultrasonic transmitter, an ultrasonic receiver, and an antenna, all connected to the controller. The ultrasonic transmitter and receiver are positioned opposite each other. The ultrasonic receiver includes a simulated outer ear that mimics the characteristics of a bat's outer ear, a signal receiver connected to the simulated outer ear to receive physical signals generated when the simulated outer ear deforms, and a bionic motion device that supports and adjusts the position and angle of the simulated outer ear. The controller can control the movement of the bionic motion device to change the position and angle of the simulated outer ear. The simulated outer ear includes a bionic outer ear and a bionic lower outer ear flap placed inside the bionic outer ear. The bionic outer ear can undergo physical deformation when receiving echo signals, and the bionic lower outer ear flap enables the echo reception process to have the characteristic of controlling the beam direction. Both the bionic outer ear and the bionic lower outer ear flap are made of flexible materials. The bionic motion device includes a head motion platform, an ear motion platform, an ear connecting rod, and a head connecting rod. The simulated outer ear and the ear motion platform are respectively set on the head motion platform. One end of the ear connecting rod is connected to the simulated outer ear, and the other end is connected to the ear motion platform. One end of the head connecting rod is connected to the simulated outer ear, and the other end is connected to the head motion platform. The head motion platform includes a first base, a first connecting rod, and a first motion platform set on a base. The first base and the first motion platform are respectively provided with multiple... The connection points of the first base and the first motion platform are connected by a first connecting rod, which is hinged to both the first base and the first motion platform. Each first connecting rod can be extended or retracted by a retractable electric cylinder driven by a servo motor, enabling the first motion platform to achieve six degrees of freedom of movement. The ear motion platform includes a second base, a second connecting rod, and a second motion platform disposed on the head motion platform. The second base and the second motion platform are respectively provided with multiple connection points, which are connected by a second connecting rod. Each second connecting rod is hinged to both the second base and the second motion platform. Each second connecting rod can be extended or retracted by a retractable electric cylinder driven by a servo motor, enabling the second motion platform to achieve six degrees of freedom of movement. The ultrasonic transmitting device includes an ultrasonic transmitter for emitting ultrasonic waves and a signal modulation device for converting digital signals sent by the controller into voltage signals; the ultrasonic signals generated by the ultrasonic transmitter have consistent signal strength in all directions. Set the current flight direction of the drone as the positive direction of the X-axis, the left and right directions of the drone's flight direction as the Y-axis, and the vertical direction of the drone's flight direction as the Z-axis. Establish two X, Y, Z spatial rectangular coordinate systems with the centroids of the two simulated outer ears as the origins; The signal receiver converts the physical information represented by the simulated outer ear deformation into a digital signal and transmits it to the controller. The controller selects an FIR filter and a Kaiser window function to filter, frame, and window the digital signal respectively. The processed echo signal is calculated using a dynamic ultrasonic positioning algorithm to obtain the position of the UAV relative to the indoor wall and other obstacles on the X, Y, and Z axes. The specific process is as follows: Based on the digital signal, the controller calculates the frequency characteristics of the echo signal to determine whether the echo signal comes from the indoor wall or other objects. The position information between the UAV and the indoor wall is the UAV's indoor position, and the position information of the UAV and other obstacles is used to help the UAV perform obstacle avoidance operations. The echo signal is matched and filtered in the range and azimuth directions to obtain the distance of the corresponding obstacle relative to the origin, and then obtains the values ​​of the obstacle on the X, Y, and Z axes in two spatial rectangular coordinate systems. When performing range matching, the difference in azimuth angle is used to determine whether the received echo signal is an error term caused by range migration.

2. The UAV positioning system based on bat-inspired ultrasonic transceiver as described in claim 1, characterized in that, Both the ear link and the head link are hollow metal rods, and they are connected to the simulated outer ear via hinges.

3. The UAV positioning system based on bat-inspired ultrasonic transceiver as described in claim 1, characterized in that, Two signal receivers are set on the head movement platform, and the root of the simulated outer ear is connected to the signal receivers through a sliding bearing.

4. A drone positioning method based on bat-inspired ultrasonic transceiver, characterized in that, include: Set the current flight direction of the drone as the positive direction of the X-axis, the left and right directions of the drone's flight direction as the Y-axis, and the vertical direction of the drone's flight direction as the Z-axis. Establish two X, Y, Z spatial rectangular coordinate systems with the centroids of the two simulated outer ears as the origins; The bionic motion device is controlled to move according to the received controller instructions, thereby changing the position and angle of the simulated outer ear; The digital signals emitted by the drone are modulated into voltage signals, and then the voltage signals are converted into ultrasonic signals before being emitted. When an ultrasonic signal encounters an obstacle, it generates an echo signal. The echo signal can be received by the simulated outer ear, causing the simulated outer ear to deform. The deformation is converted into a digital signal and transmitted to the controller. The controller calculates the position of the obstacle relative to the drone based on the digital signal, thereby realizing indoor positioning and obstacle avoidance of the drone. The obstacles include walls and other objects outside the walls that can generate echo signals. By using a dynamic ultrasonic positioning algorithm to locate the position of the drone relative to the wall, the drone can be located. By using a dynamic ultrasonic positioning algorithm to locate the distance of the drone relative to other objects, the drone can avoid obstacles. The simulated outer ear includes a bionic outer ear and a bionic lower outer ear flap placed inside the bionic outer ear. The bionic outer ear can undergo physical deformation when receiving echo signals, and the bionic lower outer ear flap can enable the echo reception process to have the characteristic of controlling the beam direction. Both the bionic outer ear and the bionic lower outer ear flap are made of flexible materials. The bionic motion device includes: a head motion platform, an ear motion platform, an ear link, and a head link; the simulated outer ear and the ear motion platform are respectively set on the head motion platform, one end of the ear link is connected to the simulated outer ear and the other end is connected to the ear motion platform, and one end of the head link is connected to the simulated outer ear and the other end is connected to the head motion platform. The head motion platform includes a first base, a first connecting rod, and a first motion platform mounted on a base. The first base and the first motion platform are respectively provided with multiple connection points. The connection points on the first base and the first motion platform are connected by the first connecting rod. The first connecting rod is hinged to the first base and the first motion platform respectively. Each first connecting rod can be extended or retracted by a retractable electric cylinder driven by a servo motor, so that the first motion platform can achieve six degrees of freedom of motion. The ultrasonic transmitting device includes an ultrasonic transmitter for emitting ultrasonic waves and a signal modulation device for converting digital signals sent by a controller into voltage signals; the ultrasonic signals generated by the ultrasonic transmitter have consistent signal strength in all directions. The ear motion platform includes a second base, a second connecting rod, and a second motion platform mounted on the head motion platform. The second base and the second motion platform are respectively provided with multiple connection points, and the connection points on the second base and the second motion platform are connected by the second connecting rod. The second connecting rod is hinged to the second base and the second motion platform respectively. Each second connecting rod can be extended or retracted by a retractable electric cylinder driven by a servo motor, so that the second motion platform can achieve six degrees of freedom of movement. The signal receiver converts the physical information represented by the simulated outer ear deformation into a digital signal and transmits it to the controller. The controller selects an FIR filter and a Kaiser window function to filter, frame, and window the digital signal respectively. The processed echo signal is calculated using a dynamic ultrasonic positioning algorithm to obtain the position of the UAV relative to the indoor wall and other obstacles on the X, Y, and Z axes. The specific process is as follows: Based on the digital signal, the controller calculates the frequency characteristics of the echo signal to determine whether the echo signal comes from the indoor wall or other objects; the echo signal is matched and filtered in the range and azimuth directions to obtain the distance of the corresponding obstacle relative to the origin, and then the values ​​of the obstacle on the X, Y, and Z axes in the two spatial rectangular coordinate systems are obtained; when performing range matching, the difference in azimuth angle is used to determine whether the received echo signal is an error term caused by range migration.

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