CN115755988B

CN115755988B - Pure orientation passive positioning method and system for unmanned aerial vehicle cluster and storage medium

Info

Publication number: CN115755988B
Application number: CN202310031278.4A
Authority: CN
Inventors: 黄衍聪; 刘焕彬; 吴树伟; 柯梓铭
Original assignee: Guangdong University of Technology
Current assignee: Guangdong University of Technology
Priority date: 2023-01-10
Filing date: 2023-01-10
Publication date: 2023-04-11
Anticipated expiration: 2043-01-10
Also published as: CN115755988A

Abstract

The invention discloses a pure orientation passive positioning method, a pure orientation passive positioning system and a pure orientation passive positioning storage medium for an unmanned aerial vehicle cluster, wherein the pure orientation passive positioning method comprises the following steps: when the unmanned aerial vehicle cluster carries out formation flight of carrying out, when the fixed unmanned aerial vehicle of unknown serial number in a certain position and the unmanned aerial vehicle in the centre of a circle send signal to the unmanned aerial vehicle of passive received signal, through the fluctuation range of signal angle when the unmanned aerial vehicle receives the unmanned aerial vehicle signal of different relative positions of analysis, find out the relation between two unmanned aerial vehicle relative positions and the signal angle, through being located the centre of a circle and the circumference on two other positions do not have the deviation and the unmanned aerial vehicle transmitting signal that the serial number is known realizes the unmanned aerial vehicle accurate positioning to passive received signal, establish unmanned aerial vehicle positioning model, and fix a position unmanned aerial vehicle through the gradient descent method. The pure-direction passive positioning method is beneficial to reducing the frequency of electromagnetic waves emitted by the unmanned aerial vehicle cluster, namely, the unmanned aerial vehicle keeps electromagnetic silence as much as possible, so that external equipment is not easy to find the existence of the unmanned aerial vehicle, and the purpose of avoiding external interference is achieved.

Description

Pure orientation passive positioning method and system for unmanned aerial vehicle cluster and storage medium

Technical Field

The invention relates to the technical field of unmanned aerial vehicles, in particular to a pure-azimuth passive positioning method and system for an unmanned aerial vehicle cluster and a storage medium.

Background

The unmanned aerial vehicle cluster is a novel cluster mode, when the cluster performs formation flight performance, electromagnetic waves emitted outwards are reduced as much as possible, so that interference of external electromagnetic fields is avoided, namely, the unmanned aerial vehicle is kept electromagnetically silent as much as possible during flight. When the positions of the unmanned aerial vehicles deviate in the flying process, the queue positions of the unmanned aerial vehicles can be adjusted by adopting a pure-direction passive positioning method, namely, a plurality of unmanned aerial vehicles in an unmanned aerial vehicle cluster are selected to transmit electromagnetic waves to other unmanned aerial vehicles in the cluster, the unmanned aerial vehicles which passively receive signals can extract direction information from the received signals, and own positioning information is obtained through the direction information. The pure orientation passive positioning reduces the interference of the outside to the unmanned aerial vehicle cluster, and also improves the positioning accuracy of the unmanned aerial vehicle.

When the unmanned aerial vehicle cluster carries out formation flying, in order to reduce the interference of an external electromagnetic field, a pure-direction passive positioning method is selected to adjust the position of the unmanned aerial vehicle, and the unmanned aerial vehicle with deviation in position extracts direction information according to the received signals and carries out corresponding position adjustment. The pure-direction passive positioning method is beneficial to reducing the frequency of electromagnetic waves emitted by the unmanned aerial vehicle cluster, namely, the unmanned aerial vehicle keeps electromagnetic silence as much as possible, so that external equipment is not easy to find the existence of the unmanned aerial vehicle, and the purpose of avoiding external interference is achieved.

Disclosure of Invention

In order to solve at least one technical problem, the invention provides a pure-direction passive positioning method, a pure-direction passive positioning system and a storage medium for an unmanned aerial vehicle cluster.

The invention provides a pure-direction passive positioning method of an unmanned aerial vehicle cluster, which comprises the following steps:

when the unmanned aerial vehicle cluster carries out formation flying, when the unmanned aerial vehicles with fixed positions but unknown numbers and the unmanned aerial vehicles with the circle centers send signals to the unmanned aerial vehicles which passively receive the signals, the relationship between the relative positions of the two unmanned aerial vehicles and the signal angles is found out by analyzing the fluctuation ranges of the signal angles when the unmanned aerial vehicles receive the unmanned aerial vehicle signals with different relative positions, and a table is generated;

the number of the opposite unmanned aerial vehicle is quickly known in a table look-up mode, the unmanned aerial vehicle which passively receives signals is accurately positioned by transmitting signals by the other two unmanned aerial vehicles which are located in the circle center and on the circumference, have no deviation in position and have known numbers, an unmanned aerial vehicle positioning model is deduced and established by utilizing the corner relation theorem of circles and triangles in a plane, and the unmanned aerial vehicle is positioned by a gradient descent method;

the positioning result of the unmanned aerial vehicle is obtained, the position of the unmanned aerial vehicle is adjusted according to the positioning result of the unmanned aerial vehicle, and the unmanned aerial vehicle with the position deviation extracts direction information according to the received signals and carries out corresponding position adjustment.

In this scheme, when the unmanned aerial vehicle of the fixed but unknown serial number in a certain position and the unmanned aerial vehicle in the centre of a circle send signal to the unmanned aerial vehicle of passive received signal, through the fluctuation range of signal angle when unmanned aerial vehicle receives the unmanned aerial vehicle signal of different relative positions of analysis, find out the relation between two unmanned aerial vehicle relative positions and the signal angle, specifically do:

when unmanned aerial vehicles numbered 00 and 01 and any unmanned aerial vehicle on the circumference send signals in the unmanned aerial vehicle cluster formation, a triangular shape taking three unmanned aerial vehicles as fixed points is obtained due to different relative positions of the two unmanned aerial vehicles on the circumference, wherein the unmanned aerial vehicles numbered 00 and 01 are respectively an unmanned aerial vehicle on the circle center and an unmanned aerial vehicle with determined position on the circumference and known number;

let the signal included angle of the unmanned aerial vehicle with unknown serial number and the unmanned aerial vehicle with serial number 00 as an included angle

The model of the unmanned aerial vehicle is abstracted into a plane geometric model, and the included angle is obtained according to different triangular shapes

The value range of (a);

based on the angle

The value range of (2) determines the interval range of the included angle between the signal sent by the unmanned aerial vehicle with unknown number and the signal sent by the unmanned aerial vehicle with 00 number, which are received by the unmanned aerial vehicle passively receiving the signal, and determines the position interval relation between the unknown signal source and the unmanned aerial vehicle.

In this scheme, learn the serial number of other side unmanned aerial vehicle fast through the mode of looking up the table, through being located the unmanned aerial vehicle transmitting signal realization that two other positions on centre of a circle and the circumference are not deviated and the serial number is known to the unmanned aerial vehicle accurate positioning of passive received signal, specifically do:

according to the traversal of all position interval relations of the unmanned aerial vehicles on the circumference in the unmanned aerial vehicle cluster formation, summarizing the unmanned aerial vehicles into a table, determining azimuth information in the table by reading the angle relation of the signals sent by the unknown signal source and the angle relations of the signals sent by the unmanned aerial vehicles with the numbers of 00 and 01, and obtaining the numbers of the unmanned aerial vehicles with unknown numbers;

substituting the coordinates and the angles of the three unmanned aerial vehicles sending signals into an unmanned aerial vehicle positioning model to realize the accurate positioning of the unmanned aerial vehicles receiving signals passively.

In this scheme, utilize circle and triangle-shaped corner relation theorem in the plane, derive and establish unmanned aerial vehicle location model, specifically do:

if there are two unmanned aerial vehicles on circumference of unmanned aerial vehicle cluster formation

The circle center of the unmanned plane is

For unmanned aerial vehicles whose position is to be determined

Providing a signal; wherein, unmanned aerial vehicle

The position information of unmanned aerial vehicle is known

Is unknown;

with unmanned aerial vehicle

As the origin of the coordinates, there is,

in the direction of

A rectangular coordinate system is established in the positive direction of the axis

Respectively are

，

Is provided with

Has the coordinates of

Due to unmanned plane

No deviation in position and known serial number, and the radius of the unmanned aerial vehicle group

Unmanned plane

The numbers are respectively

Then, then

，

，

；

Unmanned plane

Receive from unmanned aerial vehicle

The included angle formed by the direction information of the received three beams of electromagnetic waves is obtained

Wherein

；

Is provided with

Are unmanned aerial vehicles respectively

And

，

and

，

and with

，

And

，

and

the distance is obtained by a distance formula of an Euclidean coordinate system, and the distance calculation formula is as follows:

and obtaining the included angle according to the cosine theorem in the triangle

The cosine value of (2) is calculated by the formula:

deducing and establishing an unmanned aerial vehicle positioning model by using the theorem of corner relation between a circle in a plane and a triangle, and respectively setting the coordinates of unmanned aerial vehicles with numbers of 00 and 01 and unmanned aerial vehicles with unknown numbers as the coordinates

Unmanned aerial vehicle in unmanned aerial vehicle positioning model

And solving the coordinate and the angle information received by the passive signal receiving unmanned aerial vehicle through the distance calculation formula and the cosine value calculation formula to obtain the coordinate position of the passive signal receiving unmanned aerial vehicle.

In this scheme, fix a position unmanned aerial vehicle through the gradient descent method, specifically do:

obtaining an unmanned aerial vehicle positioning model, converting cosine values of angle signals received by an unmanned aerial vehicle in the unmanned aerial vehicle positioning model into angle values, defining a loss function, and solving the unmanned aerial vehicle by a gradient descent method

The coordinate position of (a);

acquiring random number initialization to-be-updated parameters, and initializing the to-be-updated parameters to

By loss function acquisition

Setting initial learning rate, and updating parameters through iterative learning;

stopping optimization when the loss function obtains a preset minimum value, and outputting the coordinate position of the unmanned aerial vehicle receiving signals

Wherein said loss function

The calculation formula of (c) is:

in this scheme, acquire unmanned aerial vehicle's location result, carry out the adjustment of unmanned aerial vehicle position according to unmanned aerial vehicle's location result, the unmanned aerial vehicle that the deviation appears in the position draws out direction information according to received signal to carry out corresponding position adjustment, specifically do:

let the target radius of the UAV cluster be

The straight line of unmanned planes numbered 00 and 01 is

The shaft is set up into a rectangular coordinate system with the number of

The target adjusting position of the unmanned aerial vehicle is as follows:

the home position of the drone, known by the number i, is set

And the position of the unmanned aerial vehicle is converted into rectangular coordinates by the conversion relation between polar coordinates and rectangular coordinates

Indicating that the initial position of the unmanned plane is

The target of the unmanned aerial vehicle is adjusted to be

Defining the horizontal adjustment range of a single unmanned aerial vehicle as follows:

；

the square sum of the transverse adjustment amplitude in the adjustment process of each unmanned aerial vehicle is obtained to serve as the integral transverse adjustment amplitude, and in order to ensure the stability of the unmanned aerial vehicle cluster in position adjustment, the target radius is solved by a grid search method in a mode of combining fine search and fine search

Such that the overall lateral adjustment amplitude is minimized.

The second aspect of the present invention further provides a pure azimuth passive positioning system for a cluster of unmanned aerial vehicles, the system comprising: the pure orientation passive positioning method program of the unmanned aerial vehicle cluster is executed by the processor to realize the following steps:

when the unmanned aerial vehicle cluster carries out formation flying, when an unmanned aerial vehicle with a fixed position but unknown number and an unmanned aerial vehicle with a circle center send signals to an unmanned aerial vehicle passively receiving the signals, the relationship between the relative positions of the two unmanned aerial vehicles and the signal angles is found out by analyzing the fluctuation range of the signal angles when the unmanned aerial vehicles receive the unmanned aerial vehicle signals with different relative positions, and a table is generated;

the number of the unmanned aerial vehicle on the other side can be quickly known in a table look-up mode, the unmanned aerial vehicle which passively receives signals can be accurately positioned by transmitting signals by two other unmanned aerial vehicles which are positioned in the circle center and on the circumference and have no position deviation and known numbers, an unmanned aerial vehicle positioning model is deduced and established by utilizing the theorem of the relationship between the circle in the plane and the corner of the triangle, and the unmanned aerial vehicle is positioned by a gradient descent method;

The third aspect of the present invention further provides a computer-readable storage medium, where the computer-readable storage medium includes a pure orientation passive positioning method program for a cluster of drones, and when the pure orientation passive positioning method program for the cluster of drones is executed by a processor, the steps of the pure orientation passive positioning method for the cluster of drones described in any one of the above are implemented.

Drawings

Fig. 1 shows a flow chart of a pure orientation passive positioning method of a cluster of drones according to the invention;

FIG. 2 shows the angle formation by a plane geometry model in the present invention

A schematic diagram of a value range;

FIG. 3 shows the distance relationship between unmanned aerial vehicles and unmanned aerial vehicles of the present invention

A schematic diagram of received electromagnetic waves;

fig. 4 shows a flow chart of the present invention for drone position adjustment;

fig. 5 shows a block diagram of a pure azimuth passive positioning system of a cluster of drones according to the invention.

Detailed Description

In order that the above objects, features and advantages of the present invention can be more clearly understood, a more particular description of the invention will be rendered by reference to the appended drawings. It should be noted that the embodiments and features of the embodiments of the present application may be combined with each other without conflict.

In the following description, numerous specific details are set forth in order to provide a thorough understanding of the present invention, however, the present invention may be practiced in other ways than those specifically described herein, and therefore the scope of the present invention is not limited by the specific embodiments disclosed below.

Fig. 1 shows a flow chart of a pure-azimuth passive positioning method of a cluster of drones according to the invention.

As shown in fig. 1, a first aspect of the present invention provides a pure orientation passive positioning method for a cluster of drones, including:

s102, when the unmanned aerial vehicle cluster carries out formation flying, when the unmanned aerial vehicle with a fixed position but unknown number and the unmanned aerial vehicle with the circle center send signals to the unmanned aerial vehicle passively receiving the signals, the fluctuation range of signal angles when the unmanned aerial vehicles receive the unmanned aerial vehicle signals with different relative positions is analyzed, the relation between the relative positions of the two unmanned aerial vehicles and the signal angles is found out, and a table is generated;

s104, the number of the opposite unmanned aerial vehicle is quickly known in a table look-up mode, the unmanned aerial vehicle which passively receives signals is accurately positioned by transmitting signals by the other two unmanned aerial vehicles which are located at the circle center and the circumference, have no deviation and are known in number, an unmanned aerial vehicle positioning model is deduced and established by using the theorem of the relationship between the circle in the plane and the corner of the triangle, and the unmanned aerial vehicle is positioned by a gradient descent method;

s106, acquiring a positioning result of the unmanned aerial vehicle, adjusting the position of the unmanned aerial vehicle according to the positioning result of the unmanned aerial vehicle, extracting direction information of the unmanned aerial vehicle with the position deviation according to the received signal, and adjusting the position correspondingly.

It should be noted that the formation of unmanned aerial vehicles consists of ten unmanned aerial vehicles, wherein the unmanned aerial vehicle with the number of FY00 is used as a circle center, the other unmanned aerial vehicles with known numbers are uniformly arranged on a certain circumference, the unmanned aerial vehicles positioned in the circle center and the other two unmanned aerial vehicles on the circumference are selected to transmit signals, the other unmanned aerial vehicles are used as devices for passively receiving the signals, when the unmanned aerial vehicles with the numbers of 00 and 01 in the formation of the unmanned aerial vehicles cluster transmit signals with any unmanned aerial vehicle on the circumference, a triangular shape with three unmanned aerial vehicles as fixed points is obtained due to different relative positions of the two unmanned aerial vehicles on the circumference, the unmanned aerial vehicles with the numbers of 00 and 01 are respectively the unmanned aerial vehicles on the circle center and the unmanned aerial vehicles with the positions determined and known numbers on the circumference, and the unmanned aerial vehicle with the number of 01 is fixed for transmitting the signals; let the signal included angle of the unmanned aerial vehicle with unknown serial number and the unmanned aerial vehicle with serial number 00 as an included angle

；

As shown in fig. 2, the unmanned aerial vehicle model is abstracted into a plane geometric model, and an included angle is obtained according to different triangle shapes

The value range of (a) is determined by the following formula, in a known rectangular coordinate system,

is taken as the origin of coordinates and is,

，

，

，

in a manner that

As the center of a circle, the radius is

Is moved within the range of (a) to (b),

radius of unmanned aerial vehicle cluster, connection

，

，

Make a triangle

The center of the inscribed circle of (2)

Is easy to obtain

Is located at

On the perpendicular bisector of (c). Because of the fact that

Therefore, it is

Should be matched with

Point on straight line

The same side of the cylinder is in the same circle, the circumferential angle of the same chord length is half of the central angle,

when the central angle takes the maximum value or the minimum value, the circumferential angle also takes the maximum value or the minimum value. It is clear that,

to

Is a distance from

Is inversely proportional to the magnitude of (1), i.e. is

Is inversely proportional; is provided with

To

Is a distance of

Thus, therefore, it is

；

According to the Pythagorean theorem:

from

，

Can obtain the product

Coordinates of (2)

And then further on

(ii) a Due to the fact that

In a manner that

Is a center with a radius of

Within the circle of (c), then:

(ii) a Due to the fact that

In the process of

Is a circle of centers, and, therefore,

. According to the coordinate relationship, obtaining an inequality:

solving the inequality to obtain

Into the value range of

To obtain

The value range of (a), preset R =100,

four different values of 40 degrees, 80 degrees, 120 degrees and 160 degrees are obtained, and the corresponding values are solved through a computer

And (4) value range. Because the angle scope that the different relative positions of unmanned aerial vehicle received does not overlap, based on the contained angle

The value range of (2) determines the interval range of the included angle between the signal sent by the unmanned aerial vehicle with unknown number and the signal sent by the unmanned aerial vehicle with 00 number, which are received by the unmanned aerial vehicle passively receiving the signal, and determines the position interval relation between the unknown signal source and the unmanned aerial vehicle. For example, unmanned aerial vehicles

The measured signal included angle between the unmanned aerial vehicle with unknown number and the unmanned aerial vehicle with the number of 00 is

Is located at

Within the range of (1). Thus, it can be judged

Unmanned aerial vehicle B is 2 unmanned aerial vehicles apart from unmanned aerial vehicle A. Because every unmanned aerial vehicle all has unmanned aerial vehicle in its both sides, consequently only according to

The range of (2) can only narrow the unmanned aerial vehicle with the position number within the range of two solutions, and can not determine the concreteAnd (4) obtaining a final solution according to the angle information sent by the unmanned aerial vehicles with the numbers of 00 and 01.

It should be noted that, because the number of the unmanned aerial vehicles on the circumference is small, all possible results can be traversed, all position interval relationships are traversed according to the unmanned aerial vehicles on the circumference in the unmanned aerial vehicle cluster formation, the relationships are summarized into a table, azimuth information is determined in the table by reading the angle relationship of the signals sent by the unknown signal source and the angle relationships of the signals sent by the unmanned aerial vehicles with the numbers of 00 and 01, and the numbers of the unmanned aerial vehicles with the unknown numbers are obtained; substituting the coordinates and the angles of the three unmanned aerial vehicles sending signals into an unmanned aerial vehicle positioning model to realize the accurate positioning of the unmanned aerial vehicles receiving signals passively.

It should be noted that, as can be seen from the geometric relationship, when the unmanned aerial vehicle located at the center of a circle and one unmanned aerial vehicle in the formation transmit a signal, an angle signal can be provided for the other unmanned aerial vehicle. According to the angle signal and the positions of the two unmanned aerial vehicles which emit signals, the unmanned aerial vehicle can determine that the unmanned aerial vehicle is positioned on the circumcircle of a triangle which takes the three unmanned aerial vehicles as fixed points, but the accurate coordinate position of the unmanned aerial vehicle can not be positioned. Therefore, one more drone is required to transmit the signal. It has two unmanned aerial vehicles on the circumference of unmanned aerial vehicle cluster formation to establish

The circle center of the unmanned plane is

For unmanned aerial vehicles to be positioned

Providing a signal; wherein, unmanned aerial vehicle

The position information of unmanned aerial vehicle is known

Is unknown;

with unmanned aerial vehicle

As the origin of the coordinates, there is,

in the direction of

A rectangular coordinate system is established in the axial positive direction, then

Respectively have the coordinates of

，

Is provided with

Has the coordinates of

Due to the unmanned plane

Unmanned plane

The numbers are respectively

Then, then

，

，

；

As shown in fig. 3, unmanned aerial vehicle

Receive from unmanned aerial vehicle

Wherein

；

Is provided with

Are respectively unmanned aerial vehicles

And

，

and

，

and

，

and

，

and

The cosine value of (2) is calculated by the formula:

Unmanned aerial vehicle in unmanned aerial vehicle positioning model

It should be noted that the included angle in the positioning model of the unmanned aerial vehicle

The cosine values and calculations are a set of more complex implicit equations, by means of generalThe method is difficult to solve, and the gradient descent method can be used for faster solving to position the unmanned aerial vehicle, and specifically comprises the following steps:

obtaining an unmanned aerial vehicle positioning model, converting cosine values of angle signals received by an unmanned aerial vehicle in the unmanned aerial vehicle positioning model into angle values, defining a loss function, and solving the unmanned aerial vehicle through a gradient descent method

The coordinate position of (a);

Passing through a loss function

Obtaining

Partial derivatives of

，

Setting an initial learning rate

And updating the parameters through iterative learning, wherein a parameter updating formula is as follows:

Wherein said loss function

The calculation formula of (c) is:

it should be noted that, because the flight speed of the unmanned aerial vehicle is fast, and the excessive lateral position adjustment is easy to bring great instability to the unmanned aerial vehicle, the lateral adjustment should be avoided as much as possible in the unmanned aerial vehicle fleet adjustment process; let the target radius of the unmanned aerial vehicle cluster be

The straight line of unmanned planes numbered 00 and 01 is

The shaft is set up into a rectangular coordinate system with the number of

The target adjustment position of the unmanned aerial vehicle is as follows:

the home position of the drone, known by the number i, is set

It is shown that,

provided with unmanned aerial vehiclesThe initial position is

The target of the unmanned aerial vehicle is adjusted to be

Defining the transverse adjustment range of a single unmanned aerial vehicle as follows:

；

the square sum of the transverse adjustment amplitude in the adjustment process of each unmanned aerial vehicle is obtained as the whole transverse adjustment amplitude, and in order to ensure the stability of the unmanned aerial vehicle cluster in position adjustment, the target radius is solved by a grid search method in a mode of combining fine search and fine search

Such that the overall lateral adjustment amplitude is minimized.

Fig. 4 shows a flow chart of the unmanned aerial vehicle position adjustment of the present invention.

Because there is interference noise in the external environment, for example wind speed, atmospheric pressure etc. can lead to unmanned aerial vehicle to adjust the route and take place the skew. Therefore, assuming that the unmanned aerial vehicle needs to recalculate its own orientation after each traveling step length is one third of the deviation between the unmanned aerial vehicle and the target position, the adjustment strategy is changed in due time. In order to accelerate the adjustment speed of the unmanned aerial vehicle, two unmanned aerial vehicles with the minimum deviation from the target position are found out again after each adjustment, a three-signal-source positioning system is formed by the two unmanned aerial vehicles and the circle center unmanned aerial vehicle, position information is provided for adjustment of the other 7 unmanned aerial vehicles, and the steps are continuously circulated, so that the unmanned aerial vehicle finally returns to the correct position. Setting noise to follow normal distribution with the mean value of 0 and the variance of one fifth of the position deviation value, simulating the process of gradually adjusting to the correct position when the unmanned aerial vehicle cluster is influenced by external factors in the high-speed driving process, and when the square sum of the offset of the unmanned aerial vehicle is less than 0.1m ² When the adjustment is finished, the adjustment is determined to be finished.

Fig. 5 shows a block diagram of a position-only passive location system of a cluster of drones according to the invention.

The second aspect of the present invention also provides a pure azimuth passive positioning system 5 for a cluster of unmanned aerial vehicles, the system comprising: a memory 51 and a processor 52, where the memory includes a pure orientation passive positioning method program of a cluster of drones, and when executed by the processor, the pure orientation passive positioning method program of the cluster of drones implements the following steps:

It should be noted that the formation of unmanned aerial vehicles comprises ten unmanned aerial vehicles, wherein the unmanned aerial vehicle numbered as FY00 is used as the center of circle, the unmanned aerial vehicles numbered as other known numbers are uniformly arranged on a certain circumference, the unmanned aerial vehicle located at the center of circle and the other two unmanned aerial vehicles on the circumference are selected to transmit signals, the other unmanned aerial vehicles are used as devices for passively receiving signals, when the unmanned aerial vehicles numbered as 00 and 01 in the formation of unmanned aerial vehicles cluster send signals with any unmanned aerial vehicle on the circumference, the triangular shape taking the three unmanned aerial vehicles as fixed points is obtained due to the different relative positions of the two unmanned aerial vehicles on the circumference, the unmanned aerial vehicles numbered as 00 and 01 are respectively the unmanned aerial vehicles on the center of circle and the unmanned aerial vehicles with the determined positions and the known numbers on the circumference, and the number is 01, the unmanned aerial vehicle is fixedly used for transmitting signals; let the signal included angle that the unmanned aerial vehicle of unknown serial number and the unmanned aerial vehicle of serial number 00 provide be the contained angle

；

Abstracting the model of the unmanned aerial vehicle into a plane geometric model, and solving an included angle according to different triangular shapes

The value range of (a) is known, in a rectangular coordinate system,

is taken as the origin of the coordinates,

，

，

，

in a manner that

As the center of a circle, the radius is

Is moved within the range of (a) to (b),

radius of unmanned aerial vehicle cluster, connection

，

，

Make a triangle

The center of the inscribed circle of (2)

Easy to obtain

Is located at

On the perpendicular bisector of (a). Because of the fact that

Therefore, it is

Should be matched with

Point on straight line

The same side of the circular arc is in the same circle, the circumferential angle of the same chord length is half of the central angle,

to

Is a distance from

Is inversely proportional to the size of (c), i.e. to

Is inversely proportional to the value of (a); is provided with

To

A distance of

Thus, it is possible to

；

According to the Pythagorean theorem:

from

，

Can obtain the product

Coordinates of (2)

And then further on

(ii) a Due to the fact that

In a manner that

Is a center with a radius of

Within the circle of (c), then:

(ii) a Due to the fact that

In a manner that

Is a circle of centers, and, therefore,

. According to the coordinate relationship, obtaining an inequality:

solving the inequality to obtain

Into the value range of

To obtain

The value range of (2) is not overlapped because the angle ranges received by different relative positions of the unmanned aerial vehicle are not overlapped based on the included angle

Is located at

Within the range of (1). Thus, it can be judged

The range of (2) can only narrow the unmanned aerial vehicle of position number in the range of two solutions, can not confirm specific position, still need according to the angle information that the unmanned aerial vehicle of number 00, 01 sent, obtain final solution.

It should be noted that, because the number of the unmanned aerial vehicles on the circumference is small, all possible results can be traversed, all the position interval relationships are traversed according to the unmanned aerial vehicles on the circumference in the unmanned aerial vehicle cluster formation and are collected into a table, the azimuth information is determined in the table by reading the angle relationship of the signals sent by the unknown signal source and the angle relationships of the signals sent by the unmanned aerial vehicles with the numbers of 00 and 01, and the numbers of the unmanned aerial vehicles with the unknown numbers are obtained; substituting the coordinates and the angles of the three unmanned aerial vehicles sending signals into an unmanned aerial vehicle positioning model to realize the accurate positioning of the unmanned aerial vehicles receiving signals passively.

It should be noted that, as can be seen from the geometric relationship, when the unmanned aerial vehicle located at the center of a circle and one unmanned aerial vehicle in the formation transmit a signal, an angle signal can be provided for the other unmanned aerial vehicle. According to the angle signal and the positions of the two unmanned aerial vehicles which emit signals, the unmanned aerial vehicle can determine that the unmanned aerial vehicle is positioned on the circumcircle of a triangle which takes the three unmanned aerial vehicles as fixed points, but the accurate coordinate position of the unmanned aerial vehicle can not be positioned. Therefore, one more drone is required to transmit the signal. Two sets of unmanned aerial vehicle cluster formation devices exist on the circumferenceMan-machine

The circle center of the unmanned plane is

For unmanned aerial vehicles to be positioned

Providing a signal; wherein, unmanned aerial vehicle

The position information of the unmanned aerial vehicle is known

Is unknown;

with unmanned aerial vehicle

As a point of origin of the coordinates,

in the direction of

Respectively have the coordinates of

，

Is provided with

Has the coordinates of

Due to unmanned plane

The position has no deviation and the serial number is known, and the radius of the unmanned aerial vehicle group is set

Unmanned plane

Are numbered respectively

Then, then

，

，

；

Unmanned plane

Receive from unmanned aerial vehicle

In which

；

Is provided with

Are respectively unmanned aerial vehicles

And

，

and with

，

And

，

and with

，

And

The cosine value of (2) is calculated by the formula:

deducing and establishing Unmanned Aerial Vehicle (UAV) station by using the theorem of the relationship between the corners of a circle and a triangle in a planeA bit model, wherein coordinates of unmanned aerial vehicles with numbers 00 and 01 and unmanned aerial vehicles with unknown numbers are respectively set as

Unmanned aerial vehicle in unmanned aerial vehicle positioning model

The cosine values and the calculation are a group of complicated implicit equations, the solution is difficult through a general method, the solution can be faster through a gradient descent method to position the unmanned aerial vehicle, and the method specifically comprises the following steps:

The coordinate position of (a);

Passing through a loss function

Obtaining

Partial derivatives of

，

Setting an initial learning rate

And updating the parameters through iterative learning, wherein the parameter updating formula is as follows:

stopping optimization when the loss function obtains a preset minimum value, and outputting the coordinate position of the unmanned aerial vehicle receiving the signal

Wherein said loss function

The calculation formula of (2) is as follows:

The straight line of unmanned planes numbered 00 and 01 is

The shaft is set up into a rectangular coordinate system with the number of

The target adjusting position of the unmanned aerial vehicle is as follows:

the home position of the drone, known by the number i, is

Converting the position of the unmanned aerial vehicle into rectangular coordinates by the conversion relation between polar coordinates and rectangular coordinates

It is shown that,

let the initial position of the drone be

The target of the unmanned aerial vehicle is adjusted to be

；

Such that the overall lateral adjustment amplitude is minimized.

Because there is interference noise in the external environment, for example wind speed, atmospheric pressure etc. can lead to unmanned aerial vehicle to adjust the route and take place the skew. Thus, assume a drone perAfter the traveling step length is one third of the deviation between the traveling step length and the target position, the self direction of the moving object needs to be recalculated, and the adjustment strategy is changed timely. In order to accelerate the adjustment speed of the unmanned aerial vehicle, two unmanned aerial vehicles with the minimum deviation from the target position are found out again after each adjustment, a three-signal-source positioning system is formed by the two unmanned aerial vehicles and the circle center unmanned aerial vehicle, position information is provided for adjustment of the rest 7 unmanned aerial vehicles, and the steps are continuously circulated, so that the unmanned aerial vehicle finally returns to the correct position. Setting noise to follow normal distribution with the mean value of 0 and the variance of one fifth of the position deviation value, simulating the process of gradually adjusting to the correct position when the unmanned aerial vehicle group is influenced by external factors in the high-speed running process, and when the square sum of the offset of the unmanned aerial vehicle is less than 0.1m ² When the adjustment is finished, the adjustment is determined.

In the several embodiments provided in the present application, it should be understood that the disclosed apparatus and method may be implemented in other ways. The above-described device embodiments are merely illustrative, for example, the division of the unit is only a logical functional division, and there may be other division ways in actual implementation, such as: multiple units or components may be combined, or may be integrated into another system, or some features may be omitted, or not implemented. In addition, the coupling, direct coupling or communication connection between the components shown or discussed may be through some interfaces, and the indirect coupling or communication connection between the devices or units may be electrical, mechanical or in other forms.

The units described as separate parts may or may not be physically separate, and parts displayed as units may or may not be physical units; can be located in one place or distributed on a plurality of network units; some or all of the units can be selected according to actual needs to achieve the purpose of the solution of the embodiment.

In addition, all the functional units in the embodiments of the present invention may be integrated into one processing unit, or each unit may be separately regarded as one unit, or two or more units may be integrated into one unit; the integrated unit can be realized in a form of hardware, or in a form of hardware plus a software functional unit.

Those of ordinary skill in the art will understand that: all or part of the steps for realizing the method embodiments can be completed by hardware related to program instructions, the program can be stored in a computer readable storage medium, and the program executes the steps comprising the method embodiments when executed; and the aforementioned storage medium includes: a mobile storage device, a Read-only memory (ROM), a Random Access Memory (RAM), a magnetic disk, an optical disk, or other various media capable of storing program codes.

Alternatively, the integrated unit of the present invention may be stored in a computer-readable storage medium if it is implemented in the form of a software functional module and sold or used as a separate product. Based on such understanding, the technical solutions of the embodiments of the present invention may be essentially implemented or a part contributing to the prior art may be embodied in the form of a software product, which is stored in a storage medium and includes several instructions for causing a computer device (which may be a personal computer, a server, or a network device) to execute all or part of the methods described in the embodiments of the present invention. And the aforementioned storage medium includes: a removable storage device, a ROM, a RAM, a magnetic or optical disk, or various other media that can store program code.

The above description is only for the specific embodiments of the present invention, but the scope of the present invention is not limited thereto, and any person skilled in the art can easily conceive of the changes or substitutions within the technical scope of the present invention, and all the changes or substitutions should be covered within the scope of the present invention. Therefore, the protection scope of the present invention shall be subject to the protection scope of the appended claims.

Claims

1. A pure azimuth passive positioning method for an unmanned aerial vehicle cluster is characterized by comprising the following steps:

acquiring a positioning result of the unmanned aerial vehicle, adjusting the position of the unmanned aerial vehicle according to the positioning result of the unmanned aerial vehicle, extracting direction information of the unmanned aerial vehicle with deviation according to the received signal, and adjusting the corresponding position;

when the unmanned aerial vehicle of fixed but unknown serial number in a certain position and the unmanned aerial vehicle in the centre of a circle send signal to the unmanned aerial vehicle of passive received signal, through the fluctuation range of signal angle when the unmanned aerial vehicle of analysis receives the unmanned aerial vehicle signal of different relative position, find out the relation between two unmanned aerial vehicle relative position and the signal angle, specifically do:

set up signal clamp of unknown serial number unmanned aerial vehicle and serial number be unmanned aerial vehicle's of 00 provisionThe angle is an included angle

The unmanned aerial vehicle model is abstracted into a plane geometric model, and the included angle is solved according to different triangular shapes>

The value range of (a);

based on the angle

The value range of the signal is judged, and the interval range of the included angle between the signal sent by the unmanned aerial vehicle with unknown number and the signal sent by the unmanned aerial vehicle with 00 number, which is received by the unmanned aerial vehicle passively receiving the signal, is used for determining the position interval relationship between the unknown signal source and the unmanned aerial vehicle;

by utilizing the theorem of the relationship between the plane middle circle and the triangle corner, an unmanned aerial vehicle positioning model is deduced and established, and the method specifically comprises the following steps:

The unmanned plane at the circle center is>

For the unmanned aerial vehicle whose position is to be determined->

Providing a signal; wherein unmanned aerial vehicle->

The position information of is known, unmanned plane->

Is unknown;

with unmanned aerial vehicle

As the origin of coordinates, is taken>

Direction is>

A rectangular coordinate system is established in the positive direction of the axis, and then>

Respectively in the coordinates of->

，

Is set based on>

Has the coordinate of->

Due to unmanned plane->

No deviation in position and known number, and the radius of the unmanned aerial vehicle group>

Unmanned plane>

Are respectively numbered>

Then->

，

，

；

Unmanned plane

Receives the signal from the unmanned aerial vehicle>

The included angle formed by the direction information of the three electromagnetic waves is acquired>

Wherein->

；

Is provided with

Are respectively unmanned aerial vehicle->

And/or>

，

And &>

，

And &>

，

And/or>

，

And/or>

The distance is obtained by a distance formula of an Euclidean coordinate system, and the distance calculation formula is as follows: />

；

The cosine value of (a) is calculated by the formula:

；

deducing and establishing an unmanned aerial vehicle positioning model by using the theorem of corner relation between a circle in a plane and a triangle, and respectively setting the coordinates of unmanned aerial vehicles with the numbers of 00 and 01 and unmanned aerial vehicles with unknown numbers as

Unmanned aerial vehicle in unmanned aerial vehicle positioning model>

Solving the coordinate and the angle information received by the passive signal receiving unmanned aerial vehicle through the distance calculation formula and the cosine value calculation formula to obtain the coordinate position of the passive signal receiving unmanned aerial vehicle;

positioning the unmanned aerial vehicle by a gradient descent method specifically comprises the following steps:

The coordinate position of (a);

Taken by the loss function->

Wherein the loss function +>

The calculation formula of (2) is as follows:

。

2. the pure azimuth passive positioning method of the unmanned aerial vehicle cluster according to claim 1, wherein the number of the opposite unmanned aerial vehicle is quickly known in a table look-up manner, and the unmanned aerial vehicle which receives signals passively is accurately positioned by transmitting signals from two other unmanned aerial vehicles which are located at the circle center and the circumference and have known numbers without deviation in position, specifically:

substituting the coordinates and the angles of the three unmanned aerial vehicles sending signals into the unmanned aerial vehicle positioning model to realize the accurate positioning of the unmanned aerial vehicles receiving signals passively.

3. The pure orientation passive positioning method of the unmanned aerial vehicle cluster according to claim 1, wherein a positioning result of the unmanned aerial vehicle is obtained, a position of the unmanned aerial vehicle is adjusted according to the positioning result of the unmanned aerial vehicle, the unmanned aerial vehicle with a deviation in position extracts direction information according to the received signal, and performs corresponding position adjustment, specifically:

let the target radius of the UAV cluster be

The straight line of the unmanned aerial vehicles with the numbers 00 and 01 is ^ 5>

The shaft is set up into a rectangular coordinate system and numbered as ^ greater than or equal to>

The target adjustment position of the unmanned aerial vehicle is as follows: />

；

The home position of the drone, known by the number i, is set

And the position of the unmanned aerial vehicle is converted into the rectangular coordinate based on the conversion relation between the polar coordinate and the rectangular coordinate>

Indicating that the initial position of the unmanned aerial vehicle is->

Unmanned aerial vehicle target adjustment the setting position is->

And defining the horizontal adjustment amplitude of the single-frame unmanned aerial vehicle as>

；

Such that the overall lateral adjustment amplitude is minimized.

4. An omnidirectional passive positioning system for a cluster of unmanned aerial vehicles, the system comprising: the pure orientation passive positioning method program of the unmanned aerial vehicle cluster is executed by the processor to realize the following steps:

acquiring a positioning result of the unmanned aerial vehicle, adjusting the position of the unmanned aerial vehicle according to the positioning result of the unmanned aerial vehicle, extracting direction information of the unmanned aerial vehicle with the position deviation according to the received signal, and adjusting the corresponding position;

when unmanned aerial vehicles numbered 00 and 01 in the unmanned aerial vehicle cluster formation send signals with any unmanned aerial vehicle on the circumference, a triangular shape taking three unmanned aerial vehicles as fixed points is obtained due to different relative positions of the two unmanned aerial vehicles on the circumference, wherein the unmanned aerial vehicles numbered 00 and 01 are respectively an unmanned aerial vehicle on the circle center and an unmanned aerial vehicle with a known number and determined position on the circumference;

let the signal included angle that the unmanned aerial vehicle of unknown serial number and the unmanned aerial vehicle of serial number 00 provide be the contained angle

The value range of (a);

based on the angle

it has two unmanned aerial vehicles on the circumference of unmanned aerial vehicle cluster formation to establish

And the unmanned plane at the circle center is->

For the unmanned aerial vehicle whose position is to be determined->

Providing a signal; wherein, unmanned aerial vehicle->

Has known position information, the unmanned plane->

Is unknown; />

With unmanned aerial vehicle

As the origin of coordinates, is taken>

Direction is->

Respectively is->

，

Is set based on>

Has the coordinate of->

Due to the fact that the unmanned plane is on or off>

Is No. 1Man-machine>

Are respectively numbered as->

Then->

，

，

；

Unmanned plane

Receive from unmanned aerial vehicle>

The included angle formed by the direction information of the three electromagnetic waves is obtained>

In which>

；

Is provided with

Are respectively unmanned aerial vehicle->

And/or>

，

And/or>

，

And/or>

，

And &>

，

And &>

；

The cosine value of (a) is calculated by the formula:

；

And is regarded as the unmanned plane in the unmanned plane positioning model>

Solving the coordinates and the angle information received by the passive signal receiving unmanned aerial vehicle through the distance calculation formula and the cosine value calculation formula to obtain the coordinate position of the passive signal receiving unmanned aerial vehicle;

The coordinate position of (a);

Taken by the loss function->

Wherein the loss function +>

The calculation formula of (2) is as follows:

。

5. a computer-readable storage medium, characterized in that: the computer-readable storage medium comprises a pure orientation passive positioning method program of a cluster of drones, which when executed by a processor, carries out the steps of a pure orientation passive positioning method of a cluster of drones according to any one of claims 1 to 3.