WO2017024673A1

WO2017024673A1 - Target positioning system and method based on radio frequency and binocular vision

Info

Publication number: WO2017024673A1
Application number: PCT/CN2015/091893
Authority: WO
Inventors: 李志强; 高少波; 桂小琰
Original assignee: 西安斯凯智能科技有限公司
Priority date: 2015-08-12
Filing date: 2015-10-14
Publication date: 2017-02-16
Also published as: CN105182319A

Abstract

A target positioning system and a target positioning method. The system comprises a target coarse positioning module (1) and a target precise positioning module (2). The target coarse positioning module (1) is provided with a signal generation unit (11) and a signal receiving unit (12). The target coarse positioning module (1) acquires the transmission time of a related signal in the air according to the time at which the signal generation unit (11) sends the related signal and the time at which the signal receiving unit (12) receives the related signal, and determines the search range of a target based on the transmission time. The target precise positioning module (2) determines coordinates of a precise location of the target according to the search range of the target.

Description

Target positioning system and method based on radio frequency and binocular vision

Technical field

The present invention relates to the field of target positioning, and in particular to a system and method for precise positioning of targets based on radio frequency and binocular vision.

Background technique

At present, the existing navigation and target tracking methods are mainly based on manual real-time control methods or GPS-based methods for target tracking or navigation. The accuracy of these navigation, positioning and tracking methods is low, and in the absence of GPS signals, such as These methods will be difficult to play an effective role in densely populated areas or indoors. In view of the above situation, the navigation and target tracking method based on monocular vision came into being. This method mainly aims to meet the needs of different tasks by setting up a camera to capture video and then processing the video. However, monocular vision lacks the spatial depth information of the target, and the accuracy of navigation, positioning and tracking is difficult to guarantee. Binocular vision can accurately determine the spatial position of the target, but the amount of calculation for the dual purpose is large, and it is difficult to meet the requirements of real-time. Therefore, there is a need to develop positioning techniques that combine real-time and accuracy to improve the accuracy of navigation and target tracking.

Summary of the invention

In order to solve the above problems, the present invention provides a target positioning system, including a target coarse positioning module and a target precise positioning module; wherein the target coarse positioning module has a signal generating unit and a signal receiving unit; Transmitting and receiving the signal-related time of the signal generating unit and the signal receiving unit to acquire a transmission time of the signal in the air, and determining a search range of the target based on the transmission time; the target precise positioning module according to the target The search range determines the exact position coordinates of the target.

Preferably, the signal generating unit is capable of transmitting an interrogation signal to the signal receiving unit and receiving a first response signal from the signal receiving unit; the signal receiving unit is capable of receiving the interrogation signal from the signal generating unit Transmitting the first response signal to the signal generating unit based on the received query signal; the target coarse positioning module is capable of recording a first time and receipt of the signal generating unit to transmit the interrogation signal a second time of the first response signal of the signal receiving unit and a third time when the signal receiving unit receives the interrogation signal and a fourth time when the signal receiving unit sends the first response signal; The target coarse positioning module acquires a first transmission time by subtracting a difference between the second time and the first time by a difference between the fourth time and the third time, and based on the Determining, by the first transmission time, a first distance between the signal generating unit and the target, and determining the target based on the acquired first distance Cable range.

Preferably, the signal generating unit is further capable of transmitting a second response signal to the signal receiving unit; The receiving unit is further capable of receiving the second response signal from the signal generating unit; the target coarse positioning module is further capable of recording a fifth time when the signal generating unit transmits the second response signal, and the signal receiving unit a sixth time at which the second response signal is received; wherein the target coarse positioning module further subtracts the fifth time and the second by subtracting the difference between the sixth time and the fourth time Obtaining a second transmission time according to the difference of time, and acquiring a second distance between the signal generating unit and the target based on the second transmission time, adding the first distance and the second distance Dividing by 2 to obtain an average distance of the signal generating unit from the target, and determining a search range of the target based on the average distance.

Preferably, the signal generating unit has a first timing unit capable of recording the first time, the second time, and the fifth time; the signal receiving unit has a second timing unit The second timing unit is capable of recording the third time, the fourth time, and the sixth time.

Preferably, the target precise positioning module comprises a binocular camera and a video processing unit; the binocular camera comprises a first camera and a second camera, capable of taking pictures within a search range of the target from different orientations and perspectives; The video processing unit is capable of processing the picture to obtain precise position coordinates of the target.

Preferably, the video processing unit controls the first camera and the second camera to capture a picture containing a target according to a search range of the target.

Preferably, the video processing unit acquires three-dimensional coordinates of one of the coordinate systems in which the first camera and the second camera are referenced by using the target-containing picture in a triangular relationship.

Preferably, the target precise positioning module further comprises a displacement sensor capable of acquiring a spatial transformation matrix between the camera coordinate system and a coordinate system of the flying device in which the target positioning system is located.

Preferably, the video processing unit is capable of converting the three-dimensional coordinates of the target in the camera coordinate system into three-dimensional coordinates of the target in the coordinate system of the flying device by using the spatial transformation matrix.

Preferably, the signal transmitting unit is disposed on the flying device, and the signal receiving unit is disposed on the target.

Another invention of the present invention provides a target positioning method, comprising: a target coarse positioning step of acquiring a transmission time of a signal in the air according to a time at which the signal is transmitted and received, and determining a search range of the target based on the transmission time. a target precise positioning step of determining a precise position coordinate of the target based on the search range of the target.

Preferably, the target coarse positioning step includes: the signal generating unit transmits an inquiry signal to the signal receiving unit; recording a first time at which the inquiry signal is transmitted; the signal receiving unit receives the inquiry signal; and recording and receiving the inquiry signal a third time; the signal receiving unit transmits a first response signal to the signal generating unit based on the received query signal, the third time, and the recorded fourth of transmitting the first response signal Time; the signal occurs Receiving, by the unit, the first response signal, the third time, and the fourth time; recording a second time of receiving the first response signal; based on the first time, the second time, the first Calculating, by the third time and the fourth time, a first distance of the signal generating unit from the target; determining a search range of the target based on the first distance; wherein, by using the second time and the first time And subtracting the difference between the fourth time and the third time to obtain the transmission time, and acquiring the first distance based on the first transmission time.

Preferably, the target coarse positioning step further comprises: the signal generating unit transmitting a second response signal to the signal receiving unit; recording a fifth time for transmitting the second response signal, and recording the second time sum Transmitting the fifth time to the signal receiving unit; the signal receiving unit receiving the second response signal, the second time, and the fifth time from the signal generating unit; a sixth time of the second response signal; obtaining a second transmission time by subtracting the difference between the sixth time and the fourth time by the difference between the fifth time and the second time, and based on the a second transmission time multiplied by a second distance between the signal generating unit and the target; adding the first distance and the second distance and dividing by 2 to obtain the distance of the signal generating unit An average distance of the target; a search range of the target is determined based on the average distance.

Preferably, the target precise positioning step further includes: a picture acquiring step, the first camera and the second camera take a picture in the target search range from different orientations and perspectives; and the video processing step processes the picture to obtain The exact position coordinates of the target.

Preferably, in the picture obtaining step, the first camera and the second camera are controlled to capture a picture containing the target according to the search range of the target.

Preferably, in the video processing step, the three-dimensional one of the coordinate systems in which the target is referenced by the first camera and the second camera is acquired by a triangular relationship using the picture containing the target. coordinate.

Preferably, the video processing step further comprises a spatial transformation matrix acquisition step of acquiring a spatial transformation matrix between a coordinate system of the first camera and the second camera and a coordinate system of a flight device in which the target positioning system is located.

Preferably, in the video processing step, the three-dimensional coordinates of the target in the coordinate system of the first camera and the second camera are converted into targets on the flying device by using the space conversion matrix. The three-dimensional coordinates in the coordinate system to obtain the precise position coordinates of the target.

The invention firstly uses the radio frequency positioning technology to realize fast search and detection of the target, and determines the search range of the target. Then, the binocular vision positioning method is used to capture the target within the determined target search range, and the target is accurately positioned to improve the positioning speed. At the same time, the system of the present invention processes only the image of the No. 1 camera, detects whether the target exists, and saves the image of the No. 2 camera, that is, only relies on the camera taken by the No. 2 camera to perform target retrieval and judgment, and completes the precise positioning of the target, so that It can greatly reduce the amount of calculation and improve the positioning efficiency.

DRAWINGS

1 is a schematic structural diagram of a target positioning system based on radio frequency and binocular vision according to the present invention;

2 is a schematic structural diagram of a signal generating unit according to the present invention;

3 is a schematic structural diagram of a signal receiving unit according to the present invention;

4 is a flow chart of positioning of a target positioning system based on radio frequency and binocular vision according to the present invention;

FIG. 5 is a flowchart of a method for coarse positioning based on a radio frequency positioning module according to the present invention; FIG.

6 is a schematic diagram of the operation of the radio frequency positioning module according to the present invention;

7 is a flow chart of a method for accurately positioning a binocular positioning module according to the present invention;

FIG. 8 is a schematic diagram of a dual target model with positioning targets according to the present invention.

detailed description

The invention is illustrated below in accordance with the embodiments shown in the drawings. The disclosed embodiments are to be considered in all respects as illustrative and not restrictive. The scope of the present invention is defined by the scope of the claims, and the scope of the claims and the scope of the claims.

FIG. 1 is a schematic structural diagram of a target positioning system based on radio frequency and binocular vision according to an embodiment of the present invention. As shown in FIG. 1, the system includes a radio frequency positioning module 1, a binocular positioning module 2, and a control module 3. The radio frequency positioning module 1 includes a signal generating unit 11, a signal receiving unit 12, a core processing unit 13, and an input and output unit. The binocular positioning module 2 includes a binocular camera unit 21, a video processing unit 22, a displacement sensor unit 23, and an input and output unit 24. The signal generating unit 11, the core processing unit 13 and the input and output unit 14 of the radio frequency positioning module 1 and the binocular camera unit 21, the video processing unit 22, the displacement sensor unit 23 and the input and output unit 24 of the binocular positioning module 2 They are all disposed on the flying device, and the above units can be connected by data lines for data transmission. The signal receiving unit 12 of the radio frequency positioning module 1 is disposed on the target, and the signal receiving unit 12 and the input and output unit 14 can be communicably connected by wireless communication, thereby implementing the signal receiving unit 12 and the radio frequency positioning module. The communication connection between the other units of 1. The control module 3 can be located on the ground and controlled by an operator. The radio frequency positioning module 1 and the binocular positioning module 2 can communicate with the control module 3 by wireless communication.

The input/output unit 14, the signal generating unit 11, and the core processing unit 13 of the radio frequency positioning module 1 are disposed on the flying device, and can communicate with each other through the data bus 15; the radio frequency positioning module 1 and the binocular The positioning modules 2 can be connected by means of data lines or the like. The control module 3 performs wireless communication with the radio frequency positioning module 1 through the input and output unit 14 of the radio frequency positioning module 1 and exchanges information. The wireless communication may include wireless communication such as Bluetooth or wifi.

FIG. 2 is a schematic diagram showing the configuration of a signal generation unit according to the embodiment. As shown in Figure 2, the signal occurs The unit 11 comprises a wireless signal transmitting device 111, a timing unit 112, a processing unit 113 and a storage unit 114, wherein the wireless signal transmitting device 111 is capable of transmitting a radio signal (i.e., an interrogation signal), and the processing unit 113 is capable of generating the signal The data information received by the unit 11 is processed, and the wireless signal transmitting apparatus 111 is controlled to transmit a radio signal, and the timing unit 112 has a timing function capable of transmitting time information of the radio signal and the signal to the wireless signal transmitting apparatus 111. The generating unit 11 receives the time information of the response signal sent by the signal receiving unit 12, and the storage unit 114 can store the time information recorded by the timing unit 112 and other data or information, etc., while the timing Unit 112 may also send the recorded time information to the core processing unit 13. Preferably, the radio transmitting device 111 is a UWB signal transmitting device capable of transmitting a UWB signal. The UWB signal is an ultra-wideband signal, and has the advantages of multi-channel, high bandwidth, low power, and the like, and operates from 3.1 GHz to 10.6 GHz.

FIG. 3 is a schematic diagram showing the configuration of a signal receiving unit according to the embodiment. As shown in FIG. 3, the signal receiving unit 12 includes a wireless signal receiving device 121, a timing unit 122, a processing unit 123, and a storage unit 124, wherein the wireless signal receiving device 121 is capable of receiving a radio from the signal generating unit 11. a signal, the processing unit 123 is capable of processing the radio signal and the data information received by the signal receiving unit 12, generating a response signal, and transmitting the response signal to the signal generating unit 11 and the core processing unit 13, The timing unit 122 has a timing function capable of recording time information of the radio signal receiving means 121 receiving the radio signal from the signal generating unit 11 and time information of the response signal transmitted by the processing unit 123, the storage unit 124 may store time information recorded by the timing unit 122, as well as other data or information, etc., while the timing unit 122 may also transmit the recorded time information to the core processing unit 13.

Returning to FIG. 1, the core processing unit 13 is capable of calculating a search range of a target by using the time information of transmitting and receiving a radio signal and transmitting and receiving related data information by the signal generating unit 11 and the signal receiving unit 12, and calculating the search range. The information is sent to the binocular positioning module 2. At the same time, the core processing unit 13 is capable of receiving information transmitted by the control module 3 and controlling the operation of the signal generating unit 11 and the signal receiving unit 12 to transmit or receive radio signals and to transmit and receive related data information, such as controlling the frequency of radio signal transmission, Channel, clock, etc.

The binocular camera unit 21 of the binocular positioning module 2 includes cameras No. 1 and No. 2. The orientation and viewing angle of the two cameras can be different, and the target can be photographed simultaneously for a specific area, and the captured picture is sent to Video processing unit 22. The video processing unit 22 internally provides a storage device (not shown), stores an image processing algorithm and can store a picture captured by a binocular camera; the video processing unit 22 can process the received picture using a stored image processing algorithm. And obtaining the precise coordinates of the target captured by the binocular camera unit 21; at the same time, the video processing unit 22 can control the binocular camera unit 21 to have a target within the search range according to the target search range information sent by the radio frequency positioning module 1. Take pictures in the area. The displacement sensor unit 23 is capable of acquiring the binocular camera unit 21 sitting A spatial transformation matrix between the calibration system and the coordinate system of the flight device, and the matrix is sent to the video processing unit 22. The input/output unit 24, the binocular camera unit 21, the video processing unit 22, and the displacement sensor unit 23 of the binocular positioning module 2 are communicably connected to each other via a data bus 25. At the same time, the binocular positioning module 2 can perform wireless communication with the control module 3 and exchange information. The wireless communication may include wireless communication such as Bluetooth or wifi.

The control module 3 has a wireless communication component such as Bluetooth or wifi (not shown), and can receive the target search range information sent by the radio frequency positioning module 1 and the target precise location information sent by the binocular positioning module 2, and display the received information in the un The illustrated display provides a reference for the operator; the operator sends control information to the RF positioning module 1 and the binocular positioning module 2 via a display or other input device (not shown).

In addition, the target positioning system further has a storage module (not shown) capable of storing information such as a positioning record of the target positioning system, the binocular positioning module 2 being communicably connected to the storage module, and capable of calling the storage. The information stored by the module.

4 is a flow chart of positioning of a target positioning system based on radio frequency and binocular vision according to the embodiment. As shown in FIG. 4, the operator energizes the target positioning system, and initializes the hardware chip of the system and the control information of the radio signal transmission through the control module 3, for example, the interface of the initialization input/output unit 14, and the radio signal. Information such as frequency, channel, clock, etc. transmitted (step S1). The operator sends a positioning task to the radio frequency positioning module 1 and the binocular positioning module 2 on the flight device through the control module 3, and the core processing unit 13 of the radio frequency positioning module 1 of the flight device determines whether a positioning task is received (step S2). The core processing unit 13 of the radio frequency positioning module 1 of the flight device determines that the positioning task has not been received (NO in step S2), and continues to wait for receiving the positioning task. If the core processing unit 13 of the radio frequency positioning module 1 determines that the positioning task is received (YES in step S2), the target is searched by the radio frequency positioning module 1 to determine the target search range (step S3), and the target search range is determined. It is sent to the binocular positioning module 2 and the control module 3 (step S4).

FIG. 5 is a flowchart of determining the target search range by the radio frequency positioning module 1 in step S3 according to the embodiment. FIG. 6 is a schematic diagram of the operation of the radio frequency positioning module 1 according to the embodiment. The process of target coarse positioning will be specifically described based on FIGS. 5 and 6. After the core processing unit 13 of the radio frequency positioning module 1 determines that the positioning task is received, the core processing unit 13 instructs the processing unit 113 of the signal generating unit 11 to cause the wireless signal transmitting device 111 to transmit with an ID. The radio signal (Poll signal) of the information, and the timing unit 112 of the signal generation unit 11 record the time T _{a at} which the above-mentioned Poll signal is transmitted and store the time T _a in the storage unit 114 of the signal generation unit 11 (step S31) ). The ID information may be a specific number of the flight device or a specific code information that the signal receiving unit 12 can recognize the signal generating unit 11. The Poll signal transmitted by the signal generating unit 11 is received by the signal receiving unit 12 on the target. The processing unit 123 of the signal receiving unit 12 determines whether the signal receiving device 121 receives the Poll signal from the signal generating unit 11 based on the ID information (step S32). If the processing unit 123 of the signal receiving unit 12 determines that the Poll signal is not received (NO in step S32), it continues to wait. If the processing unit 123 determines the signal receiving unit 12 receives the Poll signal (step S32), the timing unit 122 of the recording signal receiving unit 12 receives the time T _b of the Poll signal and stores the The storage unit 124 of the signal receiving unit 12 is described (step S33). The processing unit 123 of the signal receiving unit 12 performs an acknowledgement process on the received Poll signal and generates a corresponding response signal (step S34), and transmits the response signal with the ID information and the response signal. transmitting the transmission time and the recording time T _d T _b together with other information to the signal generation unit 11 (step S35). After receiving the information sent by the signal receiving unit 12, the processing unit 113 of the signal generating unit 11 determines whether the response signal sent in step S35 and the time T _d and the time T _b are received according to the ID information. (Step S36). If the processing unit 113 of the signal generation unit 11 determines that the response signal or the like is not received (step S36: NO), it continues to wait. If the signal generating unit 11 receives the response information (Step S36: YES) signals, the timing signal generating unit 11 of the recording unit 112 receives the response time T _c signal to the signal generating and storing The storage unit 114 of the unit 11 (step S37), while the signal generation unit 11 performs a confirmation process on the received response signal. The signal generation unit 11 transmits all of the above-described time information T _a , T _b , T _c , T _d to the core processing unit 13, which calculates a wireless signal (Poll signal) and a response signal to fly in the air. The sum of the times used is T ₁ =(T _c -T _a )-(T _d -T _b ). Meanwhile, since the flying speed of the signal in the air can be regarded as equivalent to the speed of light, it is possible to measure the distance between the flying device and the target as d ₁ = (T ₁ × light speed) / 2 (step S38).

Since the clocks of the signal receiving unit 12 and the signal generating unit 11 may be out of synchronization, that is, there is a clock difference, if the time T ₁ in which the wireless signal is directly used to fly in the air is received by the signal receiving unit 12 The time T _{b of} the signal is subtracted from the time T _{a of} the signal transmitted by the signal generating unit 11, that is, (T _b -T _a ), because the signal receiving unit 12 and the signal generating unit 11 The existence of a clock difference between the above results in an inaccurate flight time of the above calculated signal in the air. However, with the method provided by the present embodiment, the adverse effects caused by the out-of-synchronization of the clocks of the signal receiving unit 12 and the signal generating unit 11 are eliminated. In addition, since (T _d -T _b ) is a time interval from the reception of the wireless signal from the signal generating unit 11 by the signal receiving unit 12 to the signal receiving unit 12 transmitting the response signal, at the time interval Internally, the wireless signal does not fly in the air and therefore needs to be subtracted to more accurately calculate the time during which the wireless signal is flying in the air.

In order to further eliminate the clock difference between the signal generating unit 11 and the signal receiving unit 12, the signal generating unit 11 issues another response signal with the ID information, the transmitting station, while receiving the response signal of the signal receiving unit 12. Information such as the time T _{e of the} other response signal and the time information T _{c is} sent to the signal receiving unit 12 (step S39). The processing unit 123 of the signal receiving unit 12 determines whether the received signal is the information transmitted in step S39 based on the ID information (step S10), if the processing unit 123 of the signal receiving unit 12 determines that the other response signal is not received, The information such as the time T _e and the time information T _c (NO in step S310) continues to wait. If the signal receiving unit 12 receives the information such as the other response signal, the time T _e, and the time information T _c (YES in step S310), the timing unit 122 of the signal receiving unit 12 records the time T at which the information is received. _f is stored in the storage unit 124 of the signal receiving unit 12 (step S311). The signal receiving unit 12 then transmits the time information T _e , T _f , T _c , T _{d in} steps S35 to S311 to the core processing unit 13, which calculates the response signal and the other The sum of the flight times of the response signals in the air is T ₂ =(T _f -T _d )-(T _e -T _c ), and the distance between the flying device and the target is measured d ₂ =(T ₂ ×speed of light)/ 2 (step S312). The core processing unit 13 averages the two distances in the above steps S38 and S312, that is, the distance between the flying device and the target: d = (d ₁ + d ₂ )/2 (step S313). The core processing unit 13 obtains the target search range (d-d _σ , d+d _σ ) based on the distance between the flying device and the target and according to the radio transmission chip self error σ (where d _σ is the distance error; the chip itself has an error The unit is a unit of time such as nanoseconds, milliseconds, etc. (step S314).

Returning to Fig. 4, the above search range is transmitted to the binocular positioning module 2 and the control module 3 (step S4).

After the radio positioning module performs coarse positioning on the target, the binocular positioning module 2 accurately locates the target according to the target search range information sent by the radio frequency positioning module (step S5).

7 is a flow chart of a method for precise positioning based on a binocular positioning module according to the present invention. FIG. 8 is a schematic diagram of a dual target model with positioning targets according to the present invention. As shown in FIG. 7, first, the video processing unit 22 controls the cameras No. 1 and No. 2 of the binocular camera unit 21 to capture the regions having targets in the search range from different perspectives and orientations, respectively, through the received target search range information. The captured picture is transmitted to the video processing unit 22 (step S51). The video processing unit 22 performs a target search on the received picture, and determines whether or not the picture having the target is retrieved (step S52). If the video processing unit 22 does not retrieve the picture containing the target (NO in step S52), the search is continued. If the video processing unit 22 retrieves the picture containing the target (YES in step S52), the video processing unit 22 processes the picture containing the target, as shown in FIG. 8, respectively, in the No. 1 camera and the No. 2 camera. The two-dimensional image coordinates P ₁ (u, v) and P ₂ (u', v') of the target in the captured picture (step S53).

Then, the three-dimensional coordinates (X, Y, Z) of the target center in the No. 1 camera coordinate system C or the No. 2 camera coordinate system C' are obtained. In the present embodiment, the No. 1 camera coordinate system C is used as a reference system for calculation and description. (Step S54); specifically, as shown in FIG. 8, the optical axis 1 of the No. 1 camera is parallel to the optical axis 2 of the No. 2 camera, and the target can be obtained in the coordinate system C with reference to the No. 1 camera by the triangular relationship. The three-dimensional coordinates P(X, Y, Z):

(k is the length of the pixel)

In the above formula, f is the focal length of the camera, L is the distance between the two cameras, d=u-u' is the parallax, and (u ₀ , v ₀ ) is the coordinate of the central pixel point of the imaging plane of the camera. Finally, according to the space conversion matrix, the three-dimensional coordinates (X _O , Y _O , Z _O ) of the target center in the coordinate system of the flying device are obtained (indicated as O) (step S55); specifically, the displacement sensor installed in the flying device The unit 23 measures the space conversion matrix T(X _x , Y _y between the (X, Y, Z) of the camera coordinate system C in the No. 1 and the coordinate system O (X _O , Y _O , Z _O ) of the flying device in real time. Z _z) of the parameters _{_{_{X x, Y y, Z z}}} , the three-dimensional coordinates of the center of the target by the number 1 may refer to the camera coordinate system C is converted to the aircraft coordinate system:

After acquiring the three-dimensional coordinates O(X _O , Y _O , Z _O ) of the target center in the coordinate system of the flying device, that is, the precise position coordinates of the target, the position coordinate information is transmitted to the control module 3 (step S6).

Thereafter, after acquiring any target, through the above calculation steps, the target space coordinates can be converted into the flight device coordinates to achieve spatially accurate positioning of the target relative to the aircraft coordinate system.

Claims

A target positioning system includes a target coarse positioning module and a target precise positioning module; wherein

The target coarse positioning module has a signal generating unit and a signal receiving unit;

The target coarse positioning module acquires a transmission time of the relevant signal in the air according to the time at which the signal generating unit and the signal receiving unit transmit and receive the relevant signals, and determines a search range of the target based on the transmission time;

The target precise positioning module determines the precise position coordinates of the target according to the search range of the target.
The target positioning system of claim 1 wherein:

The signal generating unit is capable of transmitting an interrogation signal to the signal receiving unit and receiving a first response signal from the signal receiving unit;

The signal receiving unit is capable of receiving the interrogation signal from the signal generating unit, and transmitting the first response signal to the signal generating unit based on the received interrogation signal;

The target coarse positioning module is capable of recording a first time when the signal generating unit transmits the inquiry signal and a second time of receiving the first response signal of the signal receiving unit, and the signal receiving unit receives the a third time of the inquiry signal and a fourth time when the signal receiving unit sends the first response signal;

The target coarse positioning module acquires the first transmission time by subtracting the difference between the second time and the first time by the difference between the fourth time and the third time, based on the Determining, by the first transmission time, a first distance between the signal generating unit and the target, and determining a search range of the target based on the acquired first distance.
The target positioning system according to claim 2, wherein:

The signal generating unit is further capable of transmitting a second response signal to the signal receiving unit;

The signal receiving unit is further capable of receiving the second response signal from the signal generating unit;

The target coarse positioning module is further configured to record a fifth time when the signal generating unit sends the second response signal, and a sixth time when the signal receiving unit receives the second response signal;

The target coarse positioning module further acquires a second transmission time by subtracting a difference between the sixth time and the fourth time by a difference between the fifth time and the second time, and based on the Determining, by the second transmission time, a second distance between the signal generating unit and the target,

Adding the first distance and the second distance and dividing by 2 to obtain an average distance of the signal generating unit from the target,

A search range of the target is determined based on the average distance.
The target positioning system according to claim 3, wherein:

The signal generating unit has a first timing unit, and the first timing unit is capable of recording the first time, the second time, and the fifth time;

The signal receiving unit has a second timing unit capable of recording the third time, the fourth time, and the sixth time.
The target positioning system according to any one of claims 1 to 4, characterized in that:

The target precise positioning module includes a binocular camera and a video processing unit;

The binocular camera includes a first camera and a second camera capable of taking pictures within a search range of the target from different orientations and angles of view;

The video processing unit is capable of processing the picture to obtain precise position coordinates of the target.
The target positioning system according to claim 5, wherein:

The video processing unit controls the first camera and the second camera to capture a picture containing a target according to a search range of the target.
The target positioning system according to claim 6, wherein:

The video processing unit acquires three-dimensional coordinates of one of the coordinate systems in which the first camera and the second camera are referenced by using the target-containing picture in a triangular relationship.
The target positioning system according to claim 7, wherein:

The target precision positioning module further includes a displacement sensor capable of acquiring a spatial transformation matrix between the camera coordinate system and a coordinate system of the flying device in which the target positioning system is located.
The target positioning system of claim 8 wherein:

The video processing unit is capable of converting, by the spatial transformation matrix, three-dimensional coordinates of the target in the camera coordinate system into three-dimensional coordinates of the target in a coordinate system of the flying device.
The target positioning system according to any one of claims 1 to 4, characterized in that the signal transmitting unit is disposed on the flying device, and the signal receiving unit is disposed on the target.
A target location method includes:

a target coarse positioning step of acquiring a transmission time of the relevant signal in the air according to a time at which the signal is transmitted and received, and determining a search range of the target based on the transmission time;

The target precise positioning step determines the precise position coordinates of the target according to the search range of the target.
The target positioning method according to claim 11, wherein the target coarse positioning step comprises:

The signal generating unit transmits an interrogation signal to the signal receiving unit;

Recording a first time when the interrogation signal is transmitted;

The signal receiving unit receives the inquiry signal;

Recording a third time of receiving the inquiry signal;

The signal receiving unit transmits a first response signal, the third time, and a recorded fourth time of transmitting the first response signal to the signal generating unit based on the received query signal;

The signal generating unit receives the first response signal, the third time, and the fourth time;

Recording a second time of receiving the first response signal;

Acquiring a first distance between the signal generating unit and the target based on the first time, the second time, the third time, and the fourth time;

Determining a search range of the target based on the first distance;

The first transmission time is obtained by subtracting the difference between the second time and the first time by the difference between the fourth time and the third time, and acquiring the location based on the first transmission time. Said the first distance.
The target positioning method according to claim 12, wherein the target coarse positioning step further comprises:

The signal generating unit sends a second response signal to the signal receiving unit;

Recording a fifth time of transmitting the second response signal, and transmitting the second time and the fifth time to the signal receiving unit;

The signal receiving unit receives the second response signal, the second time, and the fifth time from the signal generating unit;

Recording a sixth time when the second response signal is received;

Obtaining a second transmission time by subtracting a difference between the sixth time and the fourth time by a difference between the fifth time and the second time, and acquiring the signal based on the second transmission time a second distance between the generating unit and the target;

Adding the first distance and the second distance and dividing by 2 to obtain an average distance of the signal generating unit from the target;

A search range of the target is determined based on the average distance.
The target positioning method according to any one of claims 11 to 13, wherein the target precise positioning step further comprises:

a picture acquisition step, the first camera and the second camera take pictures from the target search range from different orientations and angles of view; the video processing step processes the picture to obtain the precise position coordinates of the target.
The target positioning method according to claim 14, wherein:

In the picture acquisition step, the first camera and the second camera are controlled to capture a picture containing the target according to the search range of the target.
The target positioning method according to claim 15, wherein:

In the video processing step, acquiring the target by the triangular relationship using the picture containing the target in the first A camera and the second camera are three-dimensional coordinates of one of the reference coordinate systems.
The target positioning method according to claim 16, wherein:

The video processing step further includes a spatial transformation matrix acquisition step of acquiring a spatial transformation matrix between a coordinate system of the first camera and the second camera and a coordinate system of a flying device in which the target positioning system is located.
The target positioning method according to claim 17, wherein:

In the video processing step, using the space conversion matrix, converting the three-dimensional coordinates of the target in the coordinate system of the first camera and the second camera into the target in the flying device The three-dimensional coordinates in the coordinate system are used to obtain the precise position coordinates of the target.