CN117991191A - Unmanned aerial vehicle positioning system, unmanned aerial vehicle positioning method and storage medium - Google Patents

Abstract

The application discloses an unmanned aerial vehicle positioning system, an unmanned aerial vehicle positioning method and a storage medium, and belongs to the technical field of positioning. The unmanned aerial vehicle positioning system comprises an unmanned aerial vehicle and a positioning auxiliary device deployed in a target area, wherein the positioning auxiliary device comprises a plurality of sound capturing devices deployed in different positions in the target area, and the target area comprises a landing area of the unmanned aerial vehicle; the unmanned aerial vehicle is used for playing target acoustic signals; the positioning auxiliary device is used for capturing acoustic signals through a plurality of sound capturing devices, searching target acoustic signals from the acoustic signals captured by each sound capturing device, obtaining the time when each sound capturing device captures the target acoustic signals, determining a plurality of pieces of time delay information, and sending the time delay information to the unmanned aerial vehicle, wherein the time delay information represents the difference value of the time when the two sound capturing devices capture the target acoustic signals; the drone is also configured to determine a location of the drone based on the plurality of latency information and the plurality of sound capturers. The system improves positioning accuracy.

Description

Unmanned aerial vehicle positioning system, unmanned aerial vehicle positioning method and storage medium

Technical Field

The application relates to the technical field of positioning, in particular to an unmanned aerial vehicle positioning system, an unmanned aerial vehicle positioning method and a storage medium.

Background

With the gradual maturity of unmanned aerial vehicle technology, unmanned aerial vehicles are increasingly applied to distribution scenes, high-altitude photography scenes and the like. Taking a delivery scene as an example, a delivery person assembles a package to be delivered to an unmanned aerial vehicle, and the unmanned aerial vehicle flies to a destination (for example, an express cabinet near a user) after taking off and climbing to a cruising height; when the unmanned aerial vehicle approaches the destination, firstly horizontally approaching the target ground based on the positioning position so as to enable the unmanned aerial vehicle to be aligned with the destination in the vertical direction as much as possible; then, vertical landing starts, and as the unmanned aerial vehicle descends in height, the error of the positioning position of the unmanned aerial vehicle becomes larger and larger, so that a visual mark plate is deployed at a destination at present, and the unmanned aerial vehicle detects the position of the visual mark plate through a camera to determine the position of the unmanned aerial vehicle relative to the destination, so that accurate landing at the destination is realized.

However, when the unmanned aerial vehicle detects the position of the vision mark plate through the camera, the unmanned aerial vehicle is easily affected by weather factors such as rain, snow, illumination and the like, so that the positioning accuracy of the unmanned aerial vehicle is poor.

Disclosure of Invention

The embodiment of the application provides an unmanned aerial vehicle positioning system, an unmanned aerial vehicle positioning method and a storage medium, which can improve the positioning precision of an unmanned aerial vehicle. The technical scheme is as follows:

In one aspect, a positioning system for a drone is provided, the positioning system for a drone includes a drone and a positioning assistance device deployed in a target area, the positioning assistance device including a plurality of sound traps deployed in different locations of the target area, the target area including a landing area of the drone;

the unmanned aerial vehicle is used for playing a target acoustic signal when the positioning position of the unmanned aerial vehicle is matched with the target area;

The positioning auxiliary device is used for capturing acoustic signals through a plurality of sound capturing devices, searching the target acoustic signals from the acoustic signals captured by each sound capturing device, obtaining the time when each sound capturing device captures the target acoustic signals, determining a plurality of time delay information, and sending the time delay information to the unmanned aerial vehicle, wherein the time delay information represents the difference value of the time when two sound capturing devices capture the target acoustic signals;

The unmanned aerial vehicle is further used for receiving the time delay information, and determining the position of the unmanned aerial vehicle based on the time delay information and the positions of the sound capturing devices.

In one aspect, a method for positioning an unmanned aerial vehicle is provided, which is executed by an unmanned aerial vehicle positioning system, wherein the unmanned aerial vehicle positioning system comprises an unmanned aerial vehicle and a positioning auxiliary device deployed in a target area, the positioning auxiliary device comprises a plurality of sound capturing devices deployed in different positions of the target area, and the target area comprises a landing area of the unmanned aerial vehicle; the method comprises the following steps:

When the positioning position of the unmanned aerial vehicle is matched with the target area, the unmanned aerial vehicle plays a target acoustic signal;

The positioning auxiliary device captures acoustic signals through a plurality of sound capturing devices, searches the target acoustic signals from the acoustic signals captured by each sound capturing device, obtains the time when each sound capturing device captures the target acoustic signals, determines a plurality of pieces of time delay information, and sends the time delay information to the unmanned aerial vehicle, wherein the time delay information represents the difference value of the time when two sound capturing devices capture the target acoustic signals;

The unmanned aerial vehicle receives the plurality of time delay information, and determines the position of the unmanned aerial vehicle based on the plurality of time delay information and the positions of the plurality of sound capturers.

In one possible implementation, the target acoustic signal is generated based on an identification code of the drone; the method further comprises the steps of:

When the positioning position of the unmanned aerial vehicle is matched with the target area, the unmanned aerial vehicle sends a landing notification to the positioning auxiliary device, wherein the landing notification carries an identification code of the unmanned aerial vehicle and is used for indicating a landing area of the unmanned aerial vehicle which needs to land in the target area;

The positioning auxiliary device receives the landing notification and generates the target acoustic signal based on an identification code carried by the landing notification;

the searching the target acoustic signal from the acoustic signals captured by each sound capturer to obtain the time when each sound capturer captures the target acoustic signal includes:

The positioning auxiliary device adopts the target acoustic signals to match the acoustic signals captured by each sound capturer, determines a target signal segment matched with the target acoustic signals in the acoustic signals captured by each sound capturer, and determines the time of capturing the target signal segment as the time of capturing the target acoustic signals by the sound capturer.

In one possible implementation, the positioning assistance device further comprises a matched filter;

The positioning auxiliary device adopts the target acoustic signals to match the acoustic signals captured by each sound capturer, determines a target signal segment matched with the target acoustic signals in the acoustic signals captured by each sound capturer, and determines the time of capturing the target signal segment as the time of capturing the target acoustic signals by the sound capturer, comprising:

The positioning auxiliary device inputs the acoustic signals captured by any sound capturer into the matched filter in a streaming manner;

The positioning auxiliary device performs matching processing on the target acoustic signal and the currently input acoustic signal through the matching filter, and outputs matching parameters of the target acoustic signal and the currently input acoustic signal in a streaming mode, wherein the matching parameters represent whether the currently input acoustic signal and the target acoustic signal are matched or not;

If the matching parameters input by the matching filter indicate that the current input acoustic signal is matched with the target acoustic signal, the positioning auxiliary device determines the moment of capturing the current input acoustic signal as the moment of capturing the target acoustic signal by the sound capturer.

In one possible implementation, if the matching parameter input by the matching filter indicates that the currently input acoustic signal matches the target acoustic signal, the positioning assistance device determines a time of capturing the currently input acoustic signal as a time of capturing the target acoustic signal by the sound capturer, including:

If the matching parameter output by the matching filter is the peak value output by the matching filter, the positioning auxiliary device determines the time corresponding to the matching parameter as the time when the sound capturing device captures the target acoustic signal, and the time corresponding to the matching parameter is the time when the sound capturing device captures the corresponding sound signal.

In one possible implementation, the playing the target acoustic signal includes:

the unmanned aerial vehicle takes the identification code of the unmanned aerial vehicle as a random seed, generates a plurality of random numbers, determines the plurality of random numbers as a plurality of code words, and plays target acoustic signals corresponding to the plurality of code words.

In one possible implementation, the drone includes a sound player;

The playing the target acoustic signals corresponding to the plurality of codewords comprises the following steps:

The unmanned aerial vehicle samples the generated plurality of code words through the sound player and plays acoustic signals corresponding to the sampled code words so that the unmanned aerial vehicle plays the target acoustic signals;

wherein the sampling rate of the sound player is the same as the generation rate of the code word.

In one possible implementation, the method further includes:

The positioning auxiliary device acquires the radial speed of the unmanned aerial vehicle, and performs Doppler distortion simulation on the target acoustic signal based on the radial speed of the unmanned aerial vehicle to obtain a first acoustic signal;

the searching the target acoustic signal from the acoustic signals captured by each sound capturer to obtain the time when each sound capturer captures the target acoustic signal includes:

The positioning auxiliary device searches the first acoustic signals from the acoustic signals captured by each sound capturer, obtains the moment when each sound capturer captures the first acoustic signals, and determines the moment when the first acoustic signals are captured as the moment when the target acoustic signals are captured.

In one possible implementation manner, the positioning auxiliary apparatus obtains a radial velocity of the unmanned aerial vehicle, performs doppler distortion simulation on the target acoustic signal based on the radial velocity of the unmanned aerial vehicle, and obtains a first acoustic signal, including:

The positioning auxiliary device respectively takes a plurality of reference speeds as radial speeds of the unmanned aerial vehicle, and performs Doppler distortion simulation on the target acoustic signals based on each radial speed to obtain a plurality of first acoustic signals;

The positioning auxiliary device searches the first acoustic signal from the acoustic signals captured by each sound capturer, obtains the moment when each sound capturer captures the first acoustic signal, and determines the moment when the first acoustic signal is captured as the moment when the target acoustic signal is captured, and the positioning auxiliary device comprises:

The positioning auxiliary device searches each first acoustic signal from the acoustic signals captured by each sound capturer, obtains the time when each sound capturer captures the searched first acoustic signal, and determines the time when the searched first acoustic signal is captured as the time when the target acoustic signal is captured.

In one possible implementation, the positioning assistance device further comprises a matched filter;

the positioning auxiliary device searches each first acoustic signal from the acoustic signals captured by each sound capturer, obtains the time when each sound capturer captures the searched first acoustic signal, and determines the time when the searched first acoustic signal is captured as the time when the target acoustic signal is captured, and the positioning auxiliary device comprises the following steps:

The positioning auxiliary device inputs the acoustic signals captured by any sound capturer into the matched filter in a streaming manner;

The positioning auxiliary device performs matching processing on each first acoustic signal and the currently input acoustic signal through the matched filter, and outputs matching parameters of each first acoustic signal and the currently input acoustic signal in a streaming mode;

The positioning auxiliary device determines the time corresponding to the maximum matching parameter in the matching parameters corresponding to each first acoustic signal as the time when the target acoustic signal is captured by the sound capturer.

In one possible implementation manner, the target acoustic signals played by different unmanned aerial vehicles are orthogonal acoustic signals, and the positioning auxiliary device is used for assisting a plurality of unmanned aerial vehicles to land in the landing area at the same time;

The positioning auxiliary device captures acoustic signals through a plurality of sound capturing devices, searches the target acoustic signals from the acoustic signals captured by each sound capturing device, obtains the time when each sound capturing device captures the target acoustic signals, determines a plurality of time delay information, and sends the time delay information to the unmanned aerial vehicle, and the positioning auxiliary device comprises:

The positioning auxiliary device searches the target acoustic signal of each unmanned aerial vehicle from the acoustic signals captured by each sound capturer respectively to obtain the moment when each sound capturer captures each target acoustic signal;

The positioning auxiliary device determines a plurality of time delay information corresponding to the target acoustic signals according to the time when each sound capturer captures the target acoustic signals, and sends the time delay information corresponding to the target acoustic signals to the unmanned aerial vehicle corresponding to the target acoustic signals.

In one aspect, an unmanned aerial vehicle is provided, the unmanned aerial vehicle cooperates with a positioning auxiliary device deployed in a target area to realize positioning, the positioning auxiliary device includes a plurality of sound capturing devices deployed in different positions in the target area, the target area includes a landing area of the unmanned aerial vehicle, and the unmanned aerial vehicle is used for: when the positioning position of the unmanned aerial vehicle is matched with the target area, playing a target acoustic signal; and receiving the plurality of time delay information, and determining the position of the unmanned aerial vehicle based on the plurality of time delay information and the positions of the plurality of sound capturers, wherein the time delay information represents the difference value of the time when the two sound capturers capture the target acoustic signal.

In one possible implementation, the target acoustic signal is generated based on an identification code of the drone; the unmanned aerial vehicle is further used for sending a landing notification to the positioning auxiliary device when the positioning position of the unmanned aerial vehicle is matched with the target area, wherein the landing notification carries an identification code of the unmanned aerial vehicle and is used for indicating that the unmanned aerial vehicle needs to land in the landing area in the target area.

In a possible implementation manner, the unmanned aerial vehicle is further configured to use an identification code of the unmanned aerial vehicle as a random seed, generate a plurality of random numbers, determine the plurality of random numbers as a plurality of codewords, and play target acoustic signals corresponding to the plurality of codewords.

In a possible implementation manner, the unmanned aerial vehicle includes a sound player, configured to sample the generated multiple codewords by using the sound player, and play an acoustic signal corresponding to the sampled codewords, so that the unmanned aerial vehicle plays the target acoustic signal; wherein the sampling rate of the sound player is the same as the generation rate of the code word.

In one possible implementation, the target acoustic signals played by different drones are orthogonal acoustic signals.

In one aspect, a positioning assistance device for positioning a drone is provided, the positioning assistance device comprising a plurality of sound traps deployed at different locations of a target area, the target area comprising a landing area of the drone; the positioning auxiliary device is used for capturing acoustic signals through a plurality of sound capturing devices, searching target acoustic signals from the acoustic signals captured by each sound capturing device, obtaining the time when each sound capturing device captures the target acoustic signals, determining a plurality of pieces of time delay information, and sending the time delay information, wherein the time delay information represents the difference value of the time when two sound capturing devices capture the target acoustic signals, and the target acoustic signals are played by the unmanned aerial vehicle when the positioning position is matched with the target area.

In one possible implementation, the target acoustic signal is generated based on an identification code of the drone; the positioning auxiliary device is further used for receiving the landing notification and generating the target acoustic signal based on an identification code carried by the landing notification; and adopting the target acoustic signals to match the acoustic signals captured by each sound capturer, determining a target signal segment matched with the target acoustic signals in the acoustic signals captured by each sound capturer, and determining the time of capturing the target signal segment as the time of capturing the target acoustic signals by the sound capturer.

In one possible implementation, the positioning assistance device further comprises a matched filter; the positioning auxiliary device is used for inputting the acoustic signals captured by any sound capturer into the matched filter in a streaming manner; performing matching processing on the target acoustic signal and the currently input acoustic signal through the matching filter, and outputting matching parameters of the target acoustic signal and the currently input acoustic signal in a streaming mode, wherein the matching parameters represent whether the currently input acoustic signal and the target acoustic signal are matched or not; and if the matching parameters input by the matching filter indicate that the current input acoustic signal is matched with the target acoustic signal, determining the moment of capturing the current input acoustic signal as the moment of capturing the target acoustic signal by the sound capturer.

In one possible implementation manner, the positioning auxiliary apparatus is configured to determine, if a matching parameter output by the matching filter is a peak value output by the matching filter, a time corresponding to the matching parameter as a time when the sound capturer captures the target acoustic signal, where the time corresponding to the matching parameter is a time when the sound capturer captures a corresponding sound signal.

In a possible implementation manner, the positioning auxiliary device is further configured to obtain a radial velocity of the unmanned aerial vehicle, and perform doppler distortion simulation on the target acoustic signal based on the radial velocity of the unmanned aerial vehicle to obtain a first acoustic signal; searching the first acoustic signals from the acoustic signals captured by each sound capturer, obtaining the moment when each sound capturer captures the first acoustic signals, and determining the moment when the first acoustic signals are captured as the moment when the target acoustic signals are captured.

In a possible implementation manner, the positioning auxiliary device is further configured to respectively use a plurality of reference speeds as radial speeds of the unmanned aerial vehicle, and perform doppler distortion simulation on the target acoustic signal based on each radial speed to obtain a plurality of first acoustic signals; searching each first acoustic signal from the acoustic signals captured by each sound capturer, obtaining the time when each sound capturer captures the searched first acoustic signal, and determining the time when the searched first acoustic signal is captured as the time when the target acoustic signal is captured.

In one possible implementation, the positioning assistance device further comprises a matched filter; the positioning auxiliary device is used for inputting the acoustic signals captured by any sound capturer into the matched filter in a streaming manner; matching each first acoustic signal with the currently input acoustic signal through the matched filter, and outputting matching parameters of each first acoustic signal and the currently input acoustic signal in a streaming mode;

And determining the moment corresponding to the maximum matching parameter in the matching parameters corresponding to each first acoustic signal as the moment when the sound capturer captures the target acoustic signal.

In one possible implementation manner, the target acoustic signals played by different unmanned aerial vehicles are orthogonal acoustic signals, and the positioning auxiliary device is used for assisting a plurality of unmanned aerial vehicles to land in the landing area at the same time; searching the target acoustic signal of each unmanned aerial vehicle from the acoustic signals captured by each sound capturer respectively to obtain the moment when each sound capturer captures each target acoustic signal; and determining a plurality of pieces of time delay information corresponding to the target acoustic signals based on the time when each sound capturer captures the target acoustic signals aiming at each target acoustic signal, and sending the plurality of pieces of time delay information of the target acoustic signals to unmanned aerial vehicles corresponding to the target acoustic signals.

In one possible implementation, the plurality of sound collectors are four sound collectors, which are respectively disposed at four vertices of the landing area; the positioning auxiliary device is further used for determining first delay information and second delay information based on the time when two diagonal sound capturing devices in the four sound capturing devices capture the target acoustic signal, and sending the first delay information and the second delay information to the unmanned aerial vehicle.

In one aspect, a computer readable storage medium having stored therein at least one program code loaded and executed by a processor to perform operations performed by a drone positioning method as any one of the possible implementations described above is provided.

In one aspect, there is provided a computer program or computer program product comprising: computer program code which, when executed by a computer, causes the computer to carry out the operations performed by the unmanned aerial vehicle positioning method as any one of the possible implementations described above.

According to the unmanned aerial vehicle positioning system, the unmanned aerial vehicle positioning method and the storage medium, the positioning auxiliary device is deployed in the target area, the positioning auxiliary device comprises the plurality of sound capturing devices deployed in different positions of the target area, after the unmanned aerial vehicle plays acoustic signals, the plurality of sound capturing devices in different positions can capture the acoustic signals, the position of the unmanned aerial vehicle can be determined based on the relative time delay of capturing the acoustic signals by the plurality of sound capturing devices in different positions and the positions of the plurality of sound capturing devices, the system is not influenced by weather, the unmanned aerial vehicle positioning system can be positioned more accurately, and the positioning precision is improved.

Drawings

In order to more clearly illustrate the technical solutions of the embodiments of the present application, the drawings required for the description of the embodiments will be briefly described below, and it is apparent that the drawings in the following description are only some embodiments of the present application, and other drawings may be obtained according to these drawings without inventive effort for a person skilled in the art.

Fig. 1 is a schematic diagram of a positioning system for an unmanned aerial vehicle according to an embodiment of the present application;

fig. 2 is a positioning flow chart of a positioning system of an unmanned aerial vehicle provided by an embodiment of the application;

Fig. 3 is a positioning flow chart of a positioning system of an unmanned aerial vehicle provided by an embodiment of the application;

Fig. 4 is a schematic diagram of codeword asynchronization under doppler effect according to an embodiment of the present application;

Fig. 5 is a schematic diagram of compensating for doppler effect interference according to an embodiment of the present application;

fig. 6 is a schematic diagram of a positioning system for a unmanned aerial vehicle according to an embodiment of the present application;

Fig. 7 is a schematic diagram of a method for determining delay information according to an embodiment of the present application;

Fig. 8 is a positioning flow chart of a positioning system of an unmanned aerial vehicle according to an embodiment of the present application;

Fig. 9 is a flowchart of a method for positioning an unmanned aerial vehicle according to an embodiment of the present application;

fig. 10 is a schematic structural diagram of an unmanned aerial vehicle according to an embodiment of the present application.

Detailed Description

For the purpose of making the objects, technical solutions and advantages of the present application more apparent, the embodiments of the present application will be described in further detail with reference to the accompanying drawings.

It is to be understood that the terms "first," "second," and the like, as used herein, may be used to describe various concepts, but are not limited by these terms unless otherwise specified. These terms are only used to distinguish one concept from another. For example, the first sound capturer may be referred to as a second sound capturer and the second sound capturer may be referred to as a first sound capturer without departing from the scope of the present application.

As used herein, the terms "at least one", "a plurality", "each", "any" and "at least one include one, two or more, a plurality includes two or more, and each refers to each of a corresponding plurality, any one refers to any one of a plurality, for example, a plurality of sound collectors includes 3 sound collectors, and each refers to each of the 3 sound collectors, any one refers to any one of the 3 sound collectors, either the first or the second or the third.

It should be noted that, the information (including but not limited to user equipment information, user personal information, etc.), data (including but not limited to data for analysis, stored data, presented data, etc.), and signals related to the present application are all authorized by the user or are fully authorized by the parties, and the collection, use, and processing of the related data is required to comply with the relevant laws and regulations and standards of the relevant countries and regions. For example, the positioning position and the like involved in the present application are all acquired with sufficient authorization.

The unmanned aerial vehicle positioning method provided by the embodiment of the application is executed by an unmanned aerial vehicle positioning system. In some embodiments, as shown in fig. 1, the drone positioning system includes a drone 101 and a positioning aid 102 deployed at a target area. Wherein the drone 101 is a short term "drone" that is a drone that is maneuvered using a radio remote control device and a self-contained programming device, or that is operated autonomously, either entirely or intermittently, by an on-board computer. The target area includes a landing area of the drone where the positioning assistance device 102 is deployed, i.e., where the positioning assistance device 102 is deployed in the landing area of the drone or where the positioning assistance device 102 is deployed in the vicinity of the landing area of the drone. By deploying the positioning assistance device 102 at or near the landing area of the drone, the positioning assistance device 102 may assist the drone 101 in positioning when the drone 101 is landing in the landing area. Alternatively, the number of the unmanned aerial vehicle 101 may be plural, that is, the plurality of unmanned aerial vehicles 101 may land in the landing area at the same time, and the positioning assistance device 102 assists the plurality of unmanned aerial vehicles 101 in positioning at the same time.

In some embodiments, the positioning aid 102 includes a plurality of sound collectors 1021 deployed at different locations in the target area, the sound collectors 1021 being any device for capturing sound, for example, the sound collectors 1021 being microphones. Since the plurality of sound collectors 102 are disposed at different positions in the target area, the distances between the unmanned aerial vehicle 101 and the plurality of sound collectors 1021 are also different, so that the unmanned aerial vehicle 101 plays the target acoustic signal, the time when the plurality of sound collectors 1021 capture the target acoustic signal is also different, and the unmanned aerial vehicle 101 can be positioned according to the relative time delay when the plurality of sound collectors 1021 capture the target acoustic signal.

In some embodiments, the unmanned aerial vehicle positioning system further comprises a routing device 103 deployed in the target area, and when the unmanned aerial vehicle 101 arrives near the target area, a communication connection with the routing device 103 can be established; the positioning assistance device 102 deployed in the target area is also established with the routing device 103. Thus, the drone 101 and the positioning assistance device 102 may communicate via the routing device 103, e.g., the positioning assistance device 102 may send latency information, etc., to the drone 101 via the routing device 103.

Fig. 2 is a positioning flow chart of a positioning system of an unmanned aerial vehicle provided by an embodiment of the application. The unmanned aerial vehicle positioning system comprises an unmanned aerial vehicle and a positioning auxiliary device deployed in a target area, wherein the positioning auxiliary device comprises a plurality of sound capturing devices deployed in different positions in the target area, and the target area comprises a landing area of the unmanned aerial vehicle; this embodiment includes:

201. the unmanned aerial vehicle is used for playing target acoustic signals when the positioning position of the unmanned aerial vehicle is matched with a target area, and the target area comprises a landing area of the unmanned aerial vehicle.

The target area comprises a landing area of the unmanned aerial vehicle. In some embodiments, the target area is a landing area of a drone. In other embodiments, the target area is larger than the landing area, including the landing area and some areas surrounding the landing area. The landing area can be any area, and the landing area is not limited in the embodiment of the present application. In some embodiments, the landing zone is the destination of the drone.

The positioning position of the unmanned aerial vehicle is obtained by positioning the unmanned aerial vehicle. In some embodiments, the position location is a position location obtained by positioning via GPS (Global Positioning System ) or RTK (Real-TIME KINEMATIC, carrier phase differential technology).

The unmanned aerial vehicle needs to fly at a certain height to avoid buildings and the like, when the unmanned aerial vehicle approaches a landing zone, the unmanned aerial vehicle falls into the landing zone from the height, and therefore, the matching of the positioning position of the unmanned aerial vehicle and the target zone means that: the positional location of the drone indicates that the drone is horizontally approaching the target area or that the drone is horizontally approaching the landing area. Optionally, the positioning position of the unmanned aerial vehicle matches with the target area, including: the difference value between the horizontal position in the positioning position of the unmanned aerial vehicle and the horizontal position of the target area is not greater than a first threshold value; or the difference between the horizontal position in the positioning position of the unmanned aerial vehicle and the horizontal position of the landing area is not greater than a second threshold value.

The horizontal position of the target area may be a horizontal position of any point in the target area, for example, a horizontal position of a center point of the target area. The horizontal position of the drop zone may be the horizontal position of any point in the drop zone, for example, the horizontal position of the center point of the drop zone.

The target acoustic signal may be any acoustic signal, and the embodiment of the present application does not limit the target acoustic signal.

202. The positioning auxiliary device is used for capturing acoustic signals through a plurality of sound capturing devices, searching target acoustic signals from the acoustic signals captured by each sound capturing device, obtaining the time when each sound capturing device captures the target acoustic signals, determining a plurality of time delay information, and sending the time delay information to the unmanned aerial vehicle, wherein the time delay information represents the difference value of the time when the two sound capturing devices capture the target acoustic signals.

A sound capturer is any device for capturing acoustic signals, for example, the sound capturer is a microphone. When the sound capturer captures the acoustic signals, all the acoustic signals in the environment are captured, so that the acoustic signals captured by the sound capturer not only contain target acoustic signals, but also contain noise signals and the like. For example, when the unmanned aerial vehicle flies, the unmanned aerial vehicle propeller can generate noise, and the acoustic signals captured by the sound capturer not only comprise target acoustic signals, but also comprise noise signals of the unmanned aerial vehicle propeller.

Thus, in order to accurately determine the time at which the sound capturers capture the target acoustic signal, the positioning aid will find the target acoustic signal from the acoustic signals captured by each sound capturer to obtain the time at which each sound capturer captures the target acoustic signal.

Because the plurality of sound capturers are deployed at different positions in the target area, the distances between the unmanned aerial vehicle and the plurality of sound capturers are different, so that the unmanned aerial vehicle plays the target acoustic signal, the time when the plurality of sound capturers capture the target acoustic signal is also different, and the unmanned aerial vehicle can position according to the relative time delay when the plurality of sound capturers capture the target acoustic signal.

203. The unmanned aerial vehicle is further configured to receive a plurality of time delay information, and determine a position of the unmanned aerial vehicle based on the plurality of time delay information and the positions of the plurality of sound traps.

According to the unmanned aerial vehicle positioning system provided by the embodiment of the application, the positioning auxiliary device is deployed in the target area, the positioning auxiliary device comprises the plurality of sound capturing devices deployed in different positions in the target area, after the unmanned aerial vehicle plays acoustic signals, the plurality of sound capturing devices in different positions can capture the acoustic signals, the position of the unmanned aerial vehicle can be determined based on the relative time delay of capturing the acoustic signals by the plurality of sound capturing devices in different positions and the positions of the plurality of sound capturing devices, the system is not influenced by weather, the positioning can be more accurately performed, and the positioning precision is improved.

Fig. 3 is a positioning flow chart of a positioning system of an unmanned aerial vehicle provided by an embodiment of the application. The unmanned aerial vehicle positioning system comprises an unmanned aerial vehicle and a positioning auxiliary device deployed in a target area, wherein the positioning auxiliary device comprises a plurality of sound capturing devices deployed in different positions in the target area, and the target area comprises a landing area of the unmanned aerial vehicle; this embodiment includes:

301. the unmanned aerial vehicle is used for sending a landing notice to the positioning auxiliary device when the positioning position of the unmanned aerial vehicle is matched with the target area, wherein the landing notice carries an identification code of the unmanned aerial vehicle and is used for indicating that the unmanned aerial vehicle needs to land in the landing area in the target area.

In the embodiment of the application, when the unmanned aerial vehicle is close to the landing area when the positioning position of the unmanned aerial vehicle is matched with the target area, the unmanned aerial vehicle needs to land in the landing area, so that the unmanned aerial vehicle sends a landing notification to the positioning auxiliary device to inform the positioning auxiliary device that the unmanned aerial vehicle needs to land, and the positioning auxiliary device assists the unmanned aerial vehicle to position.

In some embodiments, the unmanned aerial vehicle positioning system further comprises a routing device with which the positioning assistance device establishes a communication connection. The unmanned aerial vehicle is used for establishing communication connection with the routing device when the positioning position of the unmanned aerial vehicle is matched with the target area; the unmanned aerial vehicle sends a landing notification to the positioning auxiliary device through the routing device.

That is, when the unmanned aerial vehicle approaches the landing zone, a routing device in the upper target zone is connected, through which the positioning assistance device of the target zone communicates.

The unmanned aerial vehicle identification code is used for identifying the unique unmanned aerial vehicle, and can be an ID of the unmanned aerial vehicle, a serial number of the unmanned aerial vehicle, a name of the unmanned aerial vehicle and the like.

302. The unmanned aerial vehicle is also used for playing the target acoustic signal based on the identification code of the unmanned aerial vehicle.

In the embodiment of the application, the target acoustic signal is played based on the identification code of the unmanned aerial vehicle, so that the target acoustic signal can be distinguished from other acoustic signals, and the positioning auxiliary device can detect and identify the target acoustic signal.

In some embodiments, the unmanned aerial vehicle plays the target acoustic signal based on the identification code of the unmanned aerial vehicle, including: the unmanned aerial vehicle takes the identification code of the unmanned aerial vehicle as a code word, and plays a target acoustic signal corresponding to the code word. In other embodiments, the unmanned aerial vehicle plays the target acoustic signal based on the identification code of the unmanned aerial vehicle, including: the unmanned aerial vehicle takes the identification code of the unmanned aerial vehicle as a random seed, generates a plurality of random numbers, determines the plurality of random numbers as a plurality of code words, and plays target acoustic signals corresponding to the plurality of code words.

It should be noted that, the embodiment of the present application is only to exemplarily illustrate the target acoustic signal played based on the identification code of the unmanned aerial vehicle, and is not limited thereto.

In one possible implementation, the drone includes a sound player through which the positioning assistance device plays the target acoustic signal. Optionally, the sound player is a speaker.

In some embodiments, the unmanned aerial vehicle plays the target acoustic signal through the sound player, comprising: the unmanned aerial vehicle samples the generated multiple code words through a sound player and plays acoustic signals corresponding to the sampled code words so that the unmanned aerial vehicle plays the target acoustic signals; wherein the sampling rate of the sound player is the same as the generation speed of the code word.

After the generated code word is input to the sound player, the sound player samples the input code word based on the sampling rate of the sound player, and if the sampling rate of the sound player is the same as the generating speed of the code word, each generated code word can be ensured to be acquired, so that the acoustic signal played by the sound player is the acoustic signal corresponding to the code words.

In some embodiments, the acoustic signal played by the drone needs to meet the following three requirements: (1) human-ear friendly: since the unmanned aerial vehicle working scene includes a city, the acoustic signal emitted by the unmanned aerial vehicle cannot cause the acoustic discomfort of the resident. (2) support concurrency detection and recognition: in the same space domain, there are sometimes multiple unmanned aerial vehicles taking off and landing, that is, the multiple unmanned aerial vehicles need to play acoustic signals at the same time, which requires that the system can detect and identify the acoustic signals of each unmanned aerial vehicle respectively. (3) The system should be able to prevent malicious attackers from forging the acoustic signals of the unmanned aerial vehicle to mislead the system, otherwise, erroneous delay information may cause the unmanned aerial vehicle to crash.

To meet the above needs, the present system employs Pseudo-Random Noise (PRN) modulation to generate an acoustic signal for the drone. Wherein the PRN acoustic signal is s= [ s ₀,s₁,s₂…s_n,…s_N-1 ].

Where s _n represents the nth codeword in the acoustic signal, n may be any positive integer. N is the number of codewords in one acoustic signal, and the embodiment of the application sets a pseudo-random seed based on the identification code of the unmanned aerial vehicle, and generates N Gaussian random variables as the acoustic signal played by the unmanned aerial vehicle.

Because the PRN acoustic signal is essentially a series of gaussian random signals, and has the same acoustic characteristics as white noise, it is difficult for the human ear to perceive the PRN acoustic signal, especially under the masking of unmanned aerial vehicle propeller noise. Another characteristic of PRN acoustic signals is that multiple PRN acoustic signals are mutually orthogonal, similar to the distance of code division multiple access (Code Division Multiple Access, CDMA), which allows us to detect and identify multiple drone acoustic signals in parallel. Also, because the PRN acoustic signals are (pseudo) randomly generated, it is difficult for a malicious attacker to generate the same acoustic signals without knowing the pseudo-random seed, and thus it is possible to prevent the malicious attacker from forging the acoustic signals of the drone.

303. The positioning auxiliary device is used for receiving the landing notification and generating a target acoustic signal based on an identification code carried by the landing notification.

After the positioning auxiliary device receives the landing notification of the unmanned aerial vehicle, the unmanned aerial vehicle corresponding to the identification code can be informed that the unmanned aerial vehicle will land, and the unmanned aerial vehicle needs to be assisted for positioning. In the embodiment of the application, the positioning auxiliary device assists the unmanned aerial vehicle in positioning by capturing the target acoustic signal played by the unmanned aerial vehicle through a plurality of sound capturing devices at different positions and determining the relative time delay of capturing the target acoustic signal by the plurality of sound capturing devices. In order to more accurately capture the target acoustic signal played by the unmanned aerial vehicle, in the embodiment of the application, the positioning auxiliary device can generate the same target acoustic signal by itself, and the target acoustic signal is used as a template to search the target acoustic signal from the captured acoustic signal.

It should be noted that, in the embodiment of the present application, the manner in which the positioning auxiliary apparatus generates the target acoustic signal based on the identification code is similar to the manner in which the unmanned aerial vehicle generates the target acoustic signal based on the identification code, and will not be described in detail herein.

304. The positioning auxiliary device is also used for capturing acoustic signals through a plurality of sound capturing devices, adopting the target acoustic signals to respectively match the acoustic signals captured by each sound capturing device, determining a target signal segment matched with the target acoustic signals in the acoustic signals captured by each sound capturing device, and determining the time for capturing the target signal segment as the time for capturing the target acoustic signals by the sound capturing device.

When the sound capturers capture the acoustic signals, various acoustic signals in the environment can be captured, so that in order to determine the moment when the sound capturers capture the target acoustic signals, the positioning auxiliary device adopts the target acoustic signals generated by the sound capturers as templates to respectively match the acoustic signals captured by each sound capturer, and if a certain signal segment in the captured acoustic signals is matched with the target acoustic signals, the signal segment contains the target acoustic signals, and therefore, the moment when the signal segment is captured is the moment when the target acoustic signals are captured.

In a possible implementation, the positioning assistance device further comprises a matched filter for detecting the acoustic signal, the idea being to use the target acoustic signal generated by the positioning assistance device itself as a template to correlate it with the captured acoustic signal; step 304 includes: the positioning auxiliary device is used for inputting the acoustic signals captured by any sound capturer into the matched filter in a streaming manner; the positioning auxiliary device is used for matching parameters of the target acoustic signal and the current input acoustic signal through the matched filter, and the matching parameters represent whether the current input acoustic signal and the target acoustic signal are matched or not; the positioning auxiliary device is used for determining the moment of capturing the current input acoustic signal as the moment of capturing the target acoustic signal by the sound capturing device if the matching parameters input by the matching filter indicate that the current input acoustic signal is matched with the target acoustic signal.

Wherein the acoustic signal captured by the sound capturer may be expressed as x=αs+w; where α represents a weakening coefficient of the target acoustic signal, s represents the target acoustic signal, w represents the gaussian random noise signal, and w= [ w ₀,w₁…w_N-1],w_n ] represents the nth codeword in the gaussian random noise signal.

To find the acoustic signal, the matched filter matches the target acoustic signal s with the captured acoustic signal x, i.e. performs a correlation calculation. The matching parameters (i.e., correlation results) can be expressed as: y=s ^Tx＝αs^Ts+s^T w. Where y is the matching parameter and s ^T is the transpose of the target acoustic signal.

The captured acoustic signal is input in a stream to a matched filter, which outputs a matching parameter y in a stream. If an apparent peak is found from the output, we can determine that the target acoustic signal was found, i.e., captured. In some embodiments, the positioning auxiliary apparatus is configured to determine, if the matching parameter output by the matching filter is a peak value of the matching filter output, a time corresponding to the matching parameter as a time when the sound capturer captures the target acoustic signal, and the time corresponding to the matching parameter is a time when the sound capturer captures the corresponding sound signal.

It should be noted that, if the signal-to-noise ratio of the acoustic signal captured by the sound capturing device is very low, the peak corresponding to the target acoustic signal is covered by the noise layer, that is, no obvious peak is in the output result, so that it is difficult to find the target acoustic signal from the captured acoustic signal. Aiming at the problem of low signal-to-noise ratio, the embodiment of the application provides an effective solution measure, namely, the length N of the target acoustic signal is increased, namely, more code words are generated to generate longer target acoustic signals.

An exemplary explanation of why generating a longer target acoustic signal can improve the signal-to-noise ratio is provided below.

Wherein, for the acoustic signal x, the signal-to-noise ratio is:

Where SNR _x represents the signal-to-noise ratio of acoustic signal x, E represents the desired function, | ² represents the 2-norm of the vector, and σ ² represents the variance of noise w. Σ|w _n|² represents the sum of |w ₁|² to |w _N-1|².

Similarly, S ^T x has a signal to noise ratio of

Where E [ ww ^T]＝σ² I ] represents the covariance of the noise W. Thus, the signal-to-noise gain of the matched filter is:

that is, the signal-to-noise ratio gain G is equal to the length N of the target acoustic signal, so we can use a longer target acoustic signal in exchange for a higher signal-to-noise ratio.

Another point to be described is that the unmanned motion causes a doppler effect, and the degree of influence of the doppler effect on the wireless signal is proportional to the motion speed of the object and inversely proportional to the propagation speed of the wireless signal. Since the propagation speed of the acoustic signal is slow, if the descent speed of the unmanned aerial vehicle is fast, the acoustic signal is affected to a high degree by the doppler effect. If the degree of influence of the Doppler effect is high, it is counterproductive to increase the length of the target acoustic signal.

Increasing the length of the target acoustic signal will be counterproductively explained as follows:

The doppler effect gradually causes the captured acoustic signal to be time domain displaced from the acoustic signal played by the drone, causing the captured codeword to be out of synchronization with the transmitted codeword. Specifically, when the doppler effect exists, the duration of the captured codeword may expand or may contract, and the duration of the captured codeword is:

Wherein v represents the radial velocity of the unmanned aerial vehicle, the radial velocity is the radial velocity of the unmanned aerial vehicle relative to the microphone, c is the propagation velocity of sound, T _c is the duration of the codeword in the target acoustic signal played by the unmanned aerial vehicle, and T' _c is the duration of the codeword after being affected by the doppler effect.

Wherein the sound capturer samples the codewords at a sampling rate of 1/T _c, that is, each codeword introduces a time offset:

as shown in fig. 4, the time offset may accumulate as the codeword increases, ultimately making the codeword asynchronous. It can be determined that when the codeword sequence number The accumulated time offset is then greater than the received codeword length T' _c. This means that the code words following the L-th code word are not synchronized with the original code word. The codeword sampled by the sound capturer is denoted s' _n, where n=0, 1,2 … ….

Wherein,

The unsynchronized codeword will severely reduce the signal-to-noise gain of the matched filter, which is rewritten as:

The s ' is the codeword s ' _n;s′^T sampled by the sound capturer, which is the transpose of s '. When the number of codewords N is smaller than L, there is no problem of codeword asynchronization, i.e., s '=s, at which time G' =g=n. When N is greater than or equal to L, s' only synchronizes with the first L codewords of s, while none of the remaining codewords are synchronized, so that:

From this, it can be seen that, once the codeword length N exceeds L, the signal-to-noise ratio gain of the matched filter decreases with increasing codeword length.

Due to the Doppler effect, the code words in the acoustic signals captured by the sound capturer are time-staggered, so that the synchronism between the code words and the templates of the matched filter is lost, and the performance of the matched filter is further reduced. In order to solve the problem, the embodiment of the application provides a method for compensating Doppler distortion.

Because the Doppler effect changes the duration of the code word, if the radial velocity v of the unmanned aerial vehicle relative to the sound capturer is known, the real duration of the received code word can be calculated, the target acoustic signal is resampled based on the real duration of the code word, a new signal template synchronous with the captured target acoustic signal can be generated, the target acoustic signal is searched by using the new signal template to compensate the Doppler effect interference, the length of the target acoustic signal can be increased as required, and the problem of low signal-to-noise ratio is solved.

In some embodiments, the positioning auxiliary apparatus is further configured to obtain a radial velocity of the unmanned aerial vehicle, and perform doppler distortion simulation on the target acoustic signal based on the radial velocity of the unmanned aerial vehicle to obtain a first acoustic signal; and the positioning auxiliary device is used for searching the first acoustic signal from the acoustic signals captured by each sound capturer, obtaining the moment of capturing the first acoustic signal by each sound capturer, and determining the moment of capturing the first acoustic signal as the moment of capturing the target acoustic signal.

The method comprises the steps of carrying out Doppler distortion simulation on a target acoustic signal based on the radial speed of the unmanned aerial vehicle, namely, determining the first length of each codeword in a captured signal based on the radial speed of the unmanned aerial vehicle, and resampling the target acoustic signal based on the first length to enable the length of each codeword in the first acoustic signal obtained through resampling to be the first length.

Alternatively, the radial velocity of the drone may be that the drone sends to the positioning assistance device. Optionally, the radial velocity of the drone is unknown to the positioning aid. As shown in fig. 5, the positioning auxiliary device is further configured to respectively use a plurality of reference speeds as radial speeds of the unmanned aerial vehicle, and perform doppler distortion simulation on the target acoustic signal based on each radial speed to obtain a plurality of first acoustic signals; the positioning auxiliary device is used for searching each first acoustic signal from the acoustic signals captured by each sound capturer, obtaining the moment when each sound capturer captures the searched first acoustic signal, and determining the moment when the searched first acoustic signal is captured as the moment when the target acoustic signal is captured.

Wherein, based on each radial velocity (v ₀,v₁…v_N-1 shown in fig. 5), the doppler distortion simulation is performed on the target acoustic signal, so as to obtain a plurality of first acoustic signals, including: a resampling interval (which may be considered as a first length of the codeword under doppler effect of the radial velocity) is determined based on each radial velocity, and the target acoustic signal is sampled based on the resampling interval to obtain a plurality of first acoustic signals.

The plurality of reference speeds are possible radial speeds of the unmanned aerial vehicle, so that only a small part of the reference speeds in the plurality of reference speeds are close to the real radial speeds of the unmanned aerial vehicle, doppler distortion simulation is conducted on the target acoustic signals based on each radial speed, and only a small part of the first acoustic signals in the obtained plurality of first acoustic signals are similar to the target acoustic signals captured by the sound capturers, and therefore when each first acoustic signal is searched from the acoustic signals captured by each sound capturer, only a small part of the first acoustic signals are searched, and even only one first acoustic signal is searched. Determining the time of capturing the first acoustic signal as the time of capturing the target acoustic signal, comprising: when only one first acoustic signal is searched, directly determining the moment of capturing the first acoustic signal as the moment of capturing the target acoustic signal; when a plurality of first acoustic signals are found, a plurality of moments of capturing the plurality of first acoustic signals can be statistically processed to obtain a moment of capturing a target acoustic signal, the moment of capturing any found first acoustic signal can be determined as the moment of capturing the target acoustic signal, which first acoustic signal is found to be the most accurate can be determined, and the moment of capturing the most accurate first acoustic signal can be determined as the moment of capturing the target acoustic signal.

Optionally, the positioning assistance device further comprises a matched filter; as shown in fig. 5, the positioning assistance device is used for inputting the sound signal captured by any sound capturer into the matched filter in a streaming manner; the positioning auxiliary device is used for carrying out matching processing on each first acoustic signal and the current input acoustic signal through the matched filter, and outputting matching parameters of each first acoustic signal and the current input acoustic signal in a streaming mode; and the positioning auxiliary device is used for determining the moment corresponding to the maximum matching parameter in the matching parameters corresponding to each first acoustic signal as the moment when the sound capturer captures the target acoustic signal.

The larger the matching parameter corresponding to the first acoustic signal, the more similar the captured acoustic signal is to the first acoustic signal, and the more accurate the first acoustic signal is found. Therefore, the first acoustic signal corresponding to the maximum matching parameter, whose reference speed is closest to the true radial speed of the drone, maximally complements the distortion caused by the doppler effect.

305. The positioning aid is further configured to determine a plurality of delay information based on the time at which each sound capturer captures the target acoustic signal, the plurality of delay information being transmitted to the drone, the delay information representing a difference in the time at which the two sound capturers capture the target acoustic signal.

The plurality of delay information may be a difference between moments when the target acoustic signal is captured by any different two sound capturing devices among the plurality of sound capturing devices.

The present application is exemplified by four sound collectors, which are respectively disposed at four vertices of the landing area, and are respectively designated as Mic0, mic1, mic2 and Mic3 clockwise, as shown in fig. 6. As shown in fig. 7 and 8, after the sound signals captured by the four sound capturing devices are input to the matched filter, the timings at which each sound capturing device captures the target acoustic signal are obtained, and the timings at which the four sound capturing devices Mic0, mic1, mic2, and Mic3 capture the target acoustic signal, respectively, are denoted as ToA0, toA1, toA2, and ToA3.

Because the diagonal sound capturers have the largest interval, the positioning based on the time delay of the diagonal sound capturers has the finest space granularity, and the obtained positioning result is more accurate. The positioning auxiliary device is also used for determining first delay information and second delay information based on the time when two diagonal sound capturing devices in the four sound capturing devices capture the target acoustic signal, and sending the first delay information and the second delay information to the unmanned aerial vehicle. Wherein the first delay information represents a difference in time when the first set of diagonal sound collectors captured the target acoustic signal and the second delay information represents a difference in time when the second set of diagonal sound collectors captured the target acoustic signal.

For example, first delay information of Mic0 and Mic2 is determined: τ _<0,2> =toa0-toa2, determine the second delay information for Mic1 and Mic 3: τ _<1,3> =toa1-toa3.

In some embodiments, the unmanned aerial vehicle positioning system further comprises a routing device through which the positioning assistance device transmits the plurality of latency information to the unmanned aerial vehicle.

306. The unmanned aerial vehicle is further configured to receive the plurality of time delay information, and determine a position of the unmanned aerial vehicle based on the plurality of time delay information and the positions of the plurality of sound traps.

The positions of the plurality of sound capturing devices may be stored in the unmanned aerial vehicle in advance, or may be sent to the unmanned aerial vehicle by the positioning auxiliary device.

The embodiment of the present application exemplifies a positioning system of an unmanned aerial vehicle shown in fig. 6, and an exemplary description is made of "determining a position of the unmanned aerial vehicle based on the plurality of delay information and the positions of the plurality of sound traps". In some embodiments, the drone may establish two hyperboloid equation sets based on the plurality of delay information and the positions of the plurality of sound capturers, and establish a three-dimensional coordinate system, with the center point of the landing area as the origin of the coordinate system, and the coordinates of the four sound capturers are defined as m0= (d, 0), m1= (0, -d, 0), m2= (-d, 0), and m3= (0, d, 0), respectively.

The two hyperboloid equation sets are:

Wherein, P is the coordinates of the unmanned aerial vehicle, p= (P _x,P_y,P_z), wherein, the symbol of P _z is positive, the symbol of P _x is determined by the symbol of τ _<0,2>, and the symbol of P _y is determined by the symbol of τ _<1,3>.

The value _P z may be determined by a height sensor of the unmanned aerial vehicle, where the height sensor may be a barometer, a LIDAR, etc., and the height sensor is not limited in the embodiment of the present application. The values of P _x and P _y can be obtained by solving the above system of equations.

It should be noted that, the embodiment of the present application is only exemplified by taking an example that an unmanned aerial vehicle falls in a landing area. In some embodiments, the target acoustic signals played by different unmanned aerial vehicles are orthogonal acoustic signals, and the positioning assistance device is used for assisting a plurality of unmanned aerial vehicles to land in a landing area at the same time. The positioning auxiliary device is also used for searching the target acoustic signal of each unmanned aerial vehicle from the acoustic signals captured by each sound capturer respectively to obtain the moment when each sound capturer captures each target acoustic signal; the positioning auxiliary device is further used for determining a plurality of time delay information corresponding to the target acoustic signals based on the time when each sound capturer captures the target acoustic signals according to each target acoustic signal, and sending the time delay information corresponding to the target acoustic signals to the unmanned aerial vehicle corresponding to the target acoustic signals.

In some embodiments, when the positioning auxiliary apparatus sends multiple delay information of the target acoustic signal to the unmanned aerial vehicle corresponding to the target acoustic signal, the delay message may be broadcasted, where the delay message carries the multiple delay information and the identification code of the unmanned aerial vehicle. After the unmanned aerial vehicle receives the time delay message, if the unmanned aerial vehicle identification code in the time delay message is not the identification code of the local machine, the time delay message is ignored, and if the unmanned aerial vehicle identification code in the time delay message is the identification code of the local machine, the position of the unmanned aerial vehicle is determined based on a plurality of time delay information in the time delay message. In other embodiments, the positioning assistance device may send latency information to the designated drone through the routing device.

Another point to be described is that the embodiment of the present application is only exemplified by generating the target acoustic signal based on the identification code of the unmanned aerial vehicle, and in another embodiment, the target acoustic signal played by the unmanned aerial vehicle may be any acoustic signal that is modulated and can be distinguished from the noise signal, and the embodiment of the present application does not limit the target acoustic signal.

According to the unmanned aerial vehicle positioning system provided by the embodiment of the application, the positioning auxiliary device is deployed in the target area, the positioning auxiliary device comprises the plurality of sound capturing devices deployed in different positions in the target area, after the unmanned aerial vehicle plays acoustic signals, the plurality of sound capturing devices in different positions can capture the acoustic signals, the position of the unmanned aerial vehicle can be determined based on the relative time delay of capturing the acoustic signals by the plurality of sound capturing devices in different positions and the positions of the plurality of sound capturing devices, the system is not influenced by weather, the positioning can be more accurately performed, and the positioning precision is improved.

According to the embodiment of the application, the acoustic signals are adopted for positioning, and because the acoustic signals radiate to the whole space, the horizontal positioning range of the unmanned aerial vehicle positioning system provided by the embodiment of the application is larger, and the difficulty in positioning the unmanned aerial vehicle based on the unmanned aerial vehicle positioning system is reduced.

The unmanned aerial vehicle positioning system provided by the embodiment of the application supports simultaneous positioning of a plurality of unmanned aerial vehicles, so that the unmanned aerial vehicles can simultaneously land in a landing area in a target area.

Fig. 9 is a flowchart of a positioning method of an unmanned aerial vehicle provided by an embodiment of the present application, where an execution subject is an unmanned aerial vehicle positioning system, and the unmanned aerial vehicle positioning system includes an unmanned aerial vehicle and a positioning auxiliary device deployed in a target area, where the positioning auxiliary device includes a plurality of sound capturing devices deployed in different positions in the target area, and the target area includes a landing area of the unmanned aerial vehicle; this embodiment includes:

901. and when the positioning position of the unmanned aerial vehicle is matched with the target area, the unmanned aerial vehicle plays the target acoustic signal.

902. The positioning auxiliary device captures acoustic signals through a plurality of sound capturing devices, searches target acoustic signals from the acoustic signals captured by each sound capturing device, obtains the time when each sound capturing device captures the target acoustic signals, determines a plurality of time delay information, sends the time delay information to the unmanned aerial vehicle, and the time delay information represents the difference value of the time when the two sound capturing devices capture the target acoustic signals.

903. The unmanned aerial vehicle receives the plurality of time delay information, and based on the plurality of time delay information and the positions of the plurality of sound capturers, the position of the unmanned aerial vehicle is determined.

In one possible implementation, the target acoustic signal is generated based on an identification code of the drone; the method further comprises the steps of:

When the positioning position of the unmanned aerial vehicle is matched with the target area, the unmanned aerial vehicle sends a landing notification to the positioning auxiliary device, wherein the landing notification carries an identification code of the unmanned aerial vehicle and is used for indicating a landing area of the unmanned aerial vehicle which needs to fall in the target area;

The positioning auxiliary device receives the landing notification and generates the target acoustic signal based on an identification code carried by the landing notification;

The searching the target acoustic signal from the acoustic signals captured by each sound capturer to obtain the time when each sound capturer captures the target acoustic signal includes:

The positioning auxiliary device adopts the target acoustic signals to match the acoustic signals captured by each sound capturer, determines a target signal segment matched with the target acoustic signals in the acoustic signals captured by each sound capturer, and determines the time of capturing the target signal segment as the time of capturing the target acoustic signals by the sound capturer.

In one possible implementation, the positioning assistance device further comprises a matched filter;

The positioning auxiliary device adopts the target acoustic signals to match acoustic signals captured by each sound capturer, determines a target signal segment matched with the target acoustic signals in the acoustic signals captured by each sound capturer, and determines the time of capturing the target signal segment as the time of capturing the target acoustic signals by the sound capturer, comprising:

the positioning auxiliary device inputs the acoustic signals captured by any sound capturer into the matched filter in a streaming manner;

the positioning auxiliary device performs matching processing on the target acoustic signal and the current input acoustic signal through the matching filter, and outputs matching parameters of the target acoustic signal and the current input acoustic signal in a streaming mode, wherein the matching parameters represent whether the current input acoustic signal and the target acoustic signal are matched or not;

If the matching parameters input by the matching filter indicate that the currently input acoustic signal matches the target acoustic signal, the positioning assistance device determines the time when the currently input acoustic signal is captured as the time when the target acoustic signal is captured by the sound capturer.

In one possible implementation, if the matching parameters input by the matching filter indicate that the currently input acoustic signal matches the target acoustic signal, the positioning assistance device determines the time of capturing the currently input acoustic signal as the time of capturing the target acoustic signal by the sound capturer, including:

If the matching parameter output by the matching filter is the peak value output by the matching filter, the positioning auxiliary device determines the time corresponding to the matching parameter as the time when the sound capturing device captures the target acoustic signal, and the time corresponding to the matching parameter is the time when the sound capturing device captures the corresponding sound signal.

In one possible implementation, the playing the target acoustic signal includes:

The unmanned aerial vehicle takes the identification code of the unmanned aerial vehicle as a random seed, generates a plurality of random numbers, determines the plurality of random numbers as a plurality of code words, and plays target acoustic signals corresponding to the plurality of code words.

In one possible implementation, the drone includes a sound player;

The playing the target acoustic signals corresponding to the plurality of codewords comprises:

The unmanned aerial vehicle samples the generated plurality of code words through the sound player and plays acoustic signals corresponding to the sampled code words so that the unmanned aerial vehicle plays the target acoustic signals;

Wherein the sampling rate of the sound player is the same as the generation rate of the codeword.

In one possible implementation, the method further includes:

the positioning auxiliary device acquires the radial speed of the unmanned aerial vehicle, and performs Doppler distortion simulation on the target acoustic signal based on the radial speed of the unmanned aerial vehicle to obtain a first acoustic signal;

The searching the target acoustic signal from the acoustic signals captured by each sound capturer to obtain the time when each sound capturer captures the target acoustic signal includes:

The positioning auxiliary device searches the first acoustic signal from the acoustic signals captured by each sound capturer, obtains the moment when the first acoustic signal is captured by each sound capturer, and determines the moment when the first acoustic signal is captured as the moment when the target acoustic signal is captured.

In one possible implementation manner, the positioning auxiliary apparatus obtains a radial velocity of the unmanned aerial vehicle, performs doppler distortion simulation on the target acoustic signal based on the radial velocity of the unmanned aerial vehicle, and obtains a first acoustic signal, including:

the positioning auxiliary device respectively takes a plurality of reference speeds as radial speeds of the unmanned aerial vehicle, and performs Doppler distortion simulation on the target acoustic signal based on each radial speed to obtain a plurality of first acoustic signals;

The positioning auxiliary device searches the first acoustic signal from the acoustic signals captured by each sound capturing device, obtains the moment when the first acoustic signal is captured by each sound capturing device, and determines the moment when the first acoustic signal is captured as the moment when the target acoustic signal is captured, and comprises the following steps:

The positioning auxiliary device searches each first acoustic signal from the acoustic signals captured by each sound capturer, obtains the moment when each sound capturer captures the searched first acoustic signal, and determines the moment when the searched first acoustic signal is captured as the moment when the target acoustic signal is captured.

In one possible implementation, the positioning assistance device further comprises a matched filter;

The positioning auxiliary device searches each first acoustic signal from the acoustic signals captured by each sound capturer, obtains the time when each sound capturer captures the searched first acoustic signal, and determines the time when the searched first acoustic signal is captured as the time when the target acoustic signal is captured, and comprises the following steps:

the positioning auxiliary device inputs the acoustic signals captured by any sound capturer into the matched filter in a streaming manner;

The positioning auxiliary device performs matching processing on each first acoustic signal and the currently input acoustic signal through the matching filter, and outputs matching parameters of each first acoustic signal and the currently input acoustic signal in a streaming mode;

The positioning auxiliary device determines the moment corresponding to the maximum matching parameter in the matching parameters corresponding to each first acoustic signal as the moment when the sound capturer captures the target acoustic signal.

In one possible implementation manner, the target acoustic signals played by different unmanned aerial vehicles are orthogonal acoustic signals, and the positioning auxiliary device is used for assisting a plurality of unmanned aerial vehicles to land in the landing area at the same time;

The positioning auxiliary device captures acoustic signals through a plurality of sound capturing devices, searches the target acoustic signals from the acoustic signals captured by each sound capturing device, obtains the time when each sound capturing device captures the target acoustic signals, determines a plurality of time delay information, and sends the time delay information to the unmanned aerial vehicle, and the positioning auxiliary device comprises:

The positioning auxiliary device searches the target acoustic signal of each unmanned aerial vehicle from the acoustic signals captured by each sound capturer respectively to obtain the moment when each sound capturer captures each target acoustic signal;

the positioning auxiliary device determines a plurality of time delay information corresponding to the target acoustic signals according to the time when each sound capturer captures the target acoustic signals, and sends the time delay information corresponding to the target acoustic signals to the unmanned aerial vehicle corresponding to the target acoustic signals.

Fig. 10 is a schematic structural diagram of a drone according to an embodiment of the present application, where the drone 1000 may have a relatively large difference due to different configurations or performances, and may include one or more processors (Central Processing Units, CPU) 1001 and one or more memories 1002, where at least one program code is stored in the memories 1002, and the at least one program code is loaded and executed by the processors 1001 to implement the methods provided in the foregoing method embodiments. Of course, the unmanned aerial vehicle may further have components such as a wired or wireless network interface, a keyboard, and an input/output interface, so as to perform input/output, and the unmanned aerial vehicle may further include other components for implementing the functions of the device, which will not be described herein.

The drone 1000 is configured to perform the steps performed by the drone in the method embodiment described above.

In an exemplary embodiment, a drone is provided that cooperates with a positioning assistance device deployed in a target area to achieve positioning, the positioning assistance device including a plurality of sound traps deployed in different locations of the target area, the target area including a landing area of the drone, the drone to: when the positioning position of the unmanned aerial vehicle is matched with the target area, playing a target acoustic signal; and receiving the plurality of time delay information, and determining the position of the unmanned aerial vehicle based on the plurality of time delay information and the positions of the plurality of sound capturers, wherein the time delay information represents the difference value of the time when the two sound capturers capture the target acoustic signal.

In one possible implementation, the target acoustic signal is generated based on an identification code of the drone; the unmanned aerial vehicle is further used for sending a landing notification to the positioning auxiliary device when the positioning position of the unmanned aerial vehicle is matched with the target area, wherein the landing notification carries an identification code of the unmanned aerial vehicle and is used for indicating that the unmanned aerial vehicle needs to fall in a landing area in the target area.

In one possible implementation manner, the unmanned aerial vehicle is further configured to use an identification code of the unmanned aerial vehicle as a random seed, generate a plurality of random numbers, determine the plurality of random numbers as a plurality of codewords, and play target acoustic signals corresponding to the plurality of codewords.

In one possible implementation manner, the unmanned aerial vehicle includes a sound player, configured to sample the generated plurality of codewords by the sound player, and play an acoustic signal corresponding to the sampled codewords, so that the unmanned aerial vehicle plays the target acoustic signal; wherein the sampling rate of the sound player is the same as the generation rate of the codeword.

In one possible implementation, the target acoustic signals played by different drones are orthogonal acoustic signals.

In an exemplary embodiment, there is also provided a positioning assistance device for positioning of a drone, the positioning assistance device including a plurality of sound traps deployed at different locations of a target area, the target area including a landing area of the drone; the positioning auxiliary device is used for capturing acoustic signals through a plurality of sound capturing devices, searching a target acoustic signal from the acoustic signals captured by each sound capturing device, obtaining the time when each sound capturing device captures the target acoustic signal, determining a plurality of time delay information, and sending the time delay information, wherein the time delay information represents the difference value of the time when two sound capturing devices capture the target acoustic signal, and the target acoustic signal is played by the unmanned aerial vehicle when the positioning position is matched with the target area.

In one possible implementation, the target acoustic signal is generated based on an identification code of the drone; the positioning auxiliary device is also used for receiving the landing notification and generating the target acoustic signal based on the identification code carried by the landing notification; and adopting the target acoustic signals to match the acoustic signals captured by each sound capturer, determining a target signal segment matched with the target acoustic signals in the acoustic signals captured by each sound capturer, and determining the time of capturing the target signal segment as the time of capturing the target acoustic signals by the sound capturer.

In one possible implementation, the positioning assistance device further comprises a matched filter; the positioning auxiliary device is used for inputting the acoustic signals captured by any sound capturer into the matched filter in a streaming manner; matching the target acoustic signal with the currently input acoustic signal through the matching filter, and outputting matching parameters of the target acoustic signal and the currently input acoustic signal in a streaming mode, wherein the matching parameters represent whether the currently input acoustic signal is matched with the target acoustic signal or not; if the matching parameters input by the matching filter indicate that the currently input acoustic signal matches the target acoustic signal, determining the moment of capturing the currently input acoustic signal as the moment of capturing the target acoustic signal by the sound capturer.

In one possible implementation manner, the positioning auxiliary apparatus is configured to determine, if the matching parameter output by the matching filter is a peak value output by the matching filter, a time corresponding to the matching parameter as a time when the sound capturer captures the target acoustic signal, where the time corresponding to the matching parameter is a time when the sound capturer captures a corresponding sound signal.

In a possible implementation manner, the positioning auxiliary device is further configured to obtain a radial velocity of the unmanned aerial vehicle, and perform doppler distortion simulation on the target acoustic signal based on the radial velocity of the unmanned aerial vehicle to obtain a first acoustic signal; and searching the first acoustic signal from the acoustic signals captured by each sound capturer, obtaining the moment when the first acoustic signal is captured by each sound capturer, and determining the moment when the first acoustic signal is captured as the moment when the target acoustic signal is captured.

In a possible implementation manner, the positioning auxiliary device is further configured to respectively use a plurality of reference speeds as radial speeds of the unmanned aerial vehicle, and perform doppler distortion simulation on the target acoustic signal based on each radial speed to obtain a plurality of first acoustic signals; searching each first acoustic signal from the acoustic signals captured by each sound capturer, obtaining the moment when each sound capturer captures the searched first acoustic signal, and determining the moment when the searched first acoustic signal is captured as the moment when the target acoustic signal is captured.

In one possible implementation, the positioning assistance device further comprises a matched filter; the positioning auxiliary device is used for inputting the acoustic signals captured by any sound capturer into the matched filter in a streaming manner; carrying out matching processing on each first acoustic signal and the currently input acoustic signal through the matching filter, and outputting matching parameters of each first acoustic signal and the currently input acoustic signal in a streaming mode;

And determining the moment corresponding to the maximum matching parameter in the matching parameters corresponding to each first acoustic signal as the moment when the target acoustic signal is captured by the sound capturer.

In one possible implementation manner, the target acoustic signals played by different unmanned aerial vehicles are orthogonal acoustic signals, and the positioning auxiliary device is used for assisting a plurality of unmanned aerial vehicles to land in the landing area at the same time; searching the target acoustic signal of each unmanned aerial vehicle from the acoustic signals captured by each sound capturer respectively to obtain the moment when each sound capturer captures each target acoustic signal; and determining a plurality of time delay information corresponding to the target acoustic signals based on the time when each sound capturer captures the target acoustic signals aiming at each target acoustic signal, and sending the plurality of time delay information of the target acoustic signals to unmanned aerial vehicles corresponding to the target acoustic signals.

In one possible implementation, the plurality of sound collectors are four sound collectors disposed at four vertices of the landing zone, respectively; the positioning auxiliary device is further used for determining first delay information and second delay information based on the time when two diagonal sound capturing devices in the four sound capturing devices capture the target acoustic signal, and sending the first delay information and the second delay information to the unmanned aerial vehicle.

In an exemplary embodiment, a computer readable storage medium is also provided, for example a memory comprising program code, which is executable by a processor in a computer device to perform the unmanned aerial vehicle positioning method in the above-described embodiment. For example, the computer readable storage medium may be ROM, random Access Memory (RAM), CD-ROM, magnetic tape, floppy disk, optical data storage device, etc.

In an exemplary embodiment, a computer program or a computer program product is also provided, which computer program or computer program product comprises computer program code which, when executed by a computer, causes the computer to implement the unmanned aerial vehicle positioning method in the above-described embodiments.

It will be understood by those skilled in the art that all or part of the steps for implementing the above embodiments may be implemented by hardware, or may be implemented by a program for instructing relevant hardware, where the program may be stored in a computer readable storage medium, and the above storage medium may be a read-only memory, a magnetic disk or an optical disk, etc.

The foregoing description of the preferred embodiments of the present application is not intended to limit the application, but rather, the application is to be construed as limited to the appended claims.

Claims (13)

1. The unmanned aerial vehicle positioning system is characterized by comprising an unmanned aerial vehicle and a positioning auxiliary device deployed in a target area, wherein the positioning auxiliary device comprises a plurality of sound capturing devices deployed in different positions of the target area, and the target area comprises a landing area of the unmanned aerial vehicle;

the unmanned aerial vehicle is used for playing a target acoustic signal when the positioning position of the unmanned aerial vehicle is matched with the target area;

The positioning auxiliary device is used for capturing acoustic signals through a plurality of sound capturing devices, searching the target acoustic signals from the acoustic signals captured by each sound capturing device, obtaining the time when each sound capturing device captures the target acoustic signals, determining a plurality of time delay information, and sending the time delay information to the unmanned aerial vehicle, wherein the time delay information represents the difference value of the time when two sound capturing devices capture the target acoustic signals;

The unmanned aerial vehicle is further used for receiving the time delay information, and determining the position of the unmanned aerial vehicle based on the time delay information and the positions of the sound capturing devices.

2. The system of claim 1, wherein the target acoustic signal is generated based on an identification code of the drone;

The unmanned aerial vehicle is further used for sending a landing notification to the positioning auxiliary device when the positioning position of the unmanned aerial vehicle is matched with the target area, wherein the landing notification carries an identification code of the unmanned aerial vehicle and is used for indicating a landing area of the unmanned aerial vehicle in the target area;

The positioning auxiliary device is further used for receiving the landing notification and generating the target acoustic signal based on an identification code carried by the landing notification;

The positioning auxiliary device is used for adopting the target acoustic signals to match the acoustic signals captured by each sound capturer, determining a target signal segment matched with the target acoustic signals in the acoustic signals captured by each sound capturer, and determining the time for capturing the target signal segment as the time for capturing the target acoustic signals by the sound capturer.

3. The system of claim 2, wherein the positioning assistance device further comprises a matched filter;

the positioning auxiliary device is used for inputting the acoustic signals captured by any sound capturer into the matched filter in a streaming manner;

the positioning auxiliary device is used for carrying out matching processing on the target acoustic signal and the currently input acoustic signal through the matched filter, outputting matching parameters of the target acoustic signal and the currently input acoustic signal in a streaming mode, and the matching parameters represent whether the currently input acoustic signal and the target acoustic signal are matched or not;

the positioning auxiliary device is configured to determine, as a time when the target acoustic signal is captured by the sound capturer, a time when the currently input acoustic signal is captured if the matching parameter input by the matching filter indicates that the currently input acoustic signal matches the target acoustic signal.

4. The system of claim 3, wherein the system further comprises a controller configured to control the controller,

And the positioning auxiliary device is used for determining the moment corresponding to the matching parameter as the moment when the sound capturer captures the target acoustic signal if the matching parameter output by the matching filter is the peak value output by the matching filter, and the moment corresponding to the matching parameter is the moment when the sound capturer captures the corresponding sound signal.

5. The system of claim 2, wherein the system further comprises a controller configured to control the controller,

The unmanned aerial vehicle is further used for taking the identification code of the unmanned aerial vehicle as a random seed, generating a plurality of random numbers, determining the plurality of random numbers as a plurality of code words, and playing target acoustic signals corresponding to the plurality of code words.

6. The system of claim 5, wherein the drone comprises a sound player;

The unmanned aerial vehicle is used for sampling the generated multiple code words through the sound player and playing the acoustic signals corresponding to the sampled code words so that the unmanned aerial vehicle plays the target acoustic signals;

wherein the sampling rate of the sound player is the same as the generation rate of the code word.

7. The system of claim 1, wherein the system further comprises a controller configured to control the controller,

The positioning auxiliary device is further used for acquiring the radial speed of the unmanned aerial vehicle, and performing Doppler distortion simulation on the target acoustic signal based on the radial speed of the unmanned aerial vehicle to obtain a first acoustic signal;

The positioning auxiliary device is used for searching the first acoustic signal from the acoustic signals captured by each sound capturer, obtaining the moment of capturing the first acoustic signal by each sound capturer, and determining the moment of capturing the first acoustic signal as the moment of capturing the target acoustic signal.

8. The system of claim 7, wherein the system further comprises a controller configured to control the controller,

The positioning auxiliary device is further used for respectively taking a plurality of reference speeds as radial speeds of the unmanned aerial vehicle, and performing Doppler distortion simulation on the target acoustic signals based on each radial speed to obtain a plurality of first acoustic signals;

the positioning auxiliary device is used for searching each first acoustic signal from the acoustic signals captured by each sound capturer, obtaining the time when each sound capturer captures the searched first acoustic signal, and determining the time when the searched first acoustic signal is captured as the time when the target acoustic signal is captured.

9. The system of claim 8, wherein the positioning assistance device further comprises a matched filter;

the positioning auxiliary device is used for inputting the acoustic signals captured by any sound capturer into the matched filter in a streaming manner;

the positioning auxiliary device is used for carrying out matching processing on each first acoustic signal and the currently input acoustic signal through the matched filter and outputting matching parameters of each first acoustic signal and the currently input acoustic signal in a streaming mode;

the positioning auxiliary device is used for determining the time corresponding to the largest matching parameter in the matching parameters corresponding to each first acoustic signal as the time when the sound capturer captures the target acoustic signal.

10. The system of claim 1, wherein the target acoustic signals played by different unmanned aerial vehicles are orthogonal acoustic signals, and wherein the positioning assistance device is configured to assist a plurality of unmanned aerial vehicles to land at the landing area simultaneously;

The positioning auxiliary device is further used for searching the target acoustic signal of each unmanned aerial vehicle from the acoustic signals captured by each sound capturer respectively to obtain the moment when each sound capturer captures each target acoustic signal;

the positioning auxiliary device is further configured to determine, for each target acoustic signal, a plurality of delay information corresponding to the target acoustic signal based on a time when each sound capturer captures the target acoustic signal, and send the plurality of delay information of the target acoustic signal to an unmanned aerial vehicle corresponding to the target acoustic signal.

11. The system of claim 1, wherein the plurality of sound traps is four sound traps, the four sound traps being disposed at four vertices of the landing zone, respectively;

The positioning auxiliary device is further used for determining first delay information and second delay information based on the time when two diagonal sound capturing devices in the four sound capturing devices capture the target acoustic signal, and sending the first delay information and the second delay information to the unmanned aerial vehicle.

12. The unmanned aerial vehicle positioning method is characterized by being executed by an unmanned aerial vehicle positioning system, wherein the unmanned aerial vehicle positioning system comprises an unmanned aerial vehicle and a positioning auxiliary device deployed in a target area, the positioning auxiliary device comprises a plurality of sound capturing devices deployed in different positions of the target area, and the target area comprises a landing area of the unmanned aerial vehicle; the method comprises the following steps:

When the positioning position of the unmanned aerial vehicle is matched with the target area, the unmanned aerial vehicle plays a target acoustic signal;

The positioning auxiliary device captures acoustic signals through a plurality of sound capturing devices, searches the target acoustic signals from the acoustic signals captured by each sound capturing device, obtains the time when each sound capturing device captures the target acoustic signals, determines a plurality of pieces of time delay information, and sends the time delay information to the unmanned aerial vehicle, wherein the time delay information represents the difference value of the time when two sound capturing devices capture the target acoustic signals;

The unmanned aerial vehicle receives the plurality of time delay information, and determines the position of the unmanned aerial vehicle based on the plurality of time delay information and the positions of the plurality of sound capturers.

13. A computer readable storage medium having stored therein at least one program code loaded and executed by a processor to perform the operations performed by the drone positioning method of claim 12.