Unmanned aerial vehicle positioning method and system based on aviation obstruction beacon

Abstract

The invention discloses an unmanned aerial vehicle positioning method and system based on an aviation obstruction beacon, the unmanned aerial vehicle positioning system comprises a parameter configuration platform, a light subsystem and an unmanned aerial vehicle subsystem, and the method comprises the steps that the parameter configuration platform sends aviation obstruction beacon information to the light subsystem and the unmanned aerial vehicle subsystem; wherein the aviation obstruction beacon information comprises serial number information and position information of aviation obstruction beacons; the light subsystem controls the aviation obstruction lights to flicker and code according to the number information; the unmanned aerial vehicle subsystem carries out video stream acquisition on the aviation obstruction beacon; decoding processing is carried out based on the collected video stream so as to obtain the number information of the aviation obstruction beacon; and determining corresponding position information according to the number information, and obtaining positioning information of the unmanned aerial vehicle according to the position information. According to the method, the aviation obstruction beacon is used as the positioning beacon, so that the method is not interfered by the environment, and high positioning precision can be provided.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of unmanned aerial vehicle positioning, and particularly relates to an unmanned aerial vehicle positioning method and system based on an aviation obstruction light. BACKGROUND

[0002] With the development of low-altitude economy, the contradiction between the limited low-altitude airspace resources and the explosive growth of low-altitude flight volume in the future will become the main contradiction of the development of low-altitude economy. To address this challenge, the airspace route needs to be densified and the flight interval needs to be compressed, thereby causing the management and control problem of large-scale dense integration flight, and further highlighting the problem of accurate positioning of unmanned aerial vehicles, especially the accurate positioning of flight height. The height of unmanned aerial vehicle low-altitude flight is not the altitude, but the true height, which is significantly affected by ground undulations and buildings, resulting in poor accuracy of low-altitude route elevation and flight height measurement, which seriously affects the safety of dense flight of aircraft groups.

[0003] At the same time, the low-altitude large-scale commercial flight has very high requirements for operational safety and reliability, at least 99.999% (i.e. "5 nines"), or even "6 nines", and if it involves manned flight, it needs to reach "10 nines". If only relying on limited sensing and positioning means such as satellite positioning and 5G+ positioning, it is difficult to meet this requirement, and more diversified positioning modes need to be explored.

[0004] At present, accurate positioning of low-altitude unmanned aerial vehicles is an important technical problem. Existing unmanned aerial vehicle positioning methods mainly include satellite navigation positioning, radio positioning, inertial navigation positioning, visual positioning, and combined positioning of the above methods. However, these traditional positioning methods have the following problems: first, low positioning accuracy, such as conventional visual positioning, inertial navigation positioning, satellite navigation positioning, etc.; second, susceptible to interference, such as radio positioning, satellite navigation positioning, etc. When a large number of unmanned aerial vehicles simultaneously perform wireless communication in the airspace, network congestion and same-frequency interference of other communication equipment can cause delay or even disconnection; even if satellite navigation is used, satellite disconnection, multipath effect, or malicious electromagnetic interference may occur due to building obstruction.

[0005] Therefore, how to propose an unmanned aerial vehicle positioning method that is not affected by environmental interference, has high positioning accuracy, and has controllable cost on the basis of existing positioning methods has become a key requirement for ensuring the safe development of low-altitude economy. SUMMARY

[0006] Embodiments of the present application provide an unmanned aerial vehicle positioning method and system based on an aviation obstruction light, aiming to improve the positioning accuracy of unmanned aerial vehicles.

[0007] Embodiments of the present application provide an unmanned aerial vehicle positioning method based on an aviation obstruction light, applied to an unmanned aerial vehicle positioning system, the unmanned aerial vehicle positioning system comprising a parameter configuration platform, a light subsystem, and an unmanned aerial vehicle subsystem, the method comprising: The parameter configuration platform sends the obstruction light information to the light subsystem and the unmanned aerial vehicle subsystem respectively; wherein, the obstruction light information comprises the number information and the position information of the obstruction light; The light subsystem controls the obstruction light to perform the flashing coding according to the number information; The unmanned aerial vehicle subsystem collects the video stream of the obstruction light; The decoding processing is performed based on the collected video stream to obtain the number information of the obstruction light; The corresponding position information is determined according to the number information, and the positioning information of the unmanned aerial vehicle is obtained according to the position information.

[0008] Further, it further comprises: The timing synchronization control is performed on the flashing coding and the video stream collection based on the PPS signal.

[0009] Further, the light subsystem controls the obstruction light to perform the flashing coding control according to the number information, comprising: The rate of the video stream collection of the unmanned aerial vehicle subsystem is obtained, and the rate of the flashing coding is set according to the rate of the video stream collection; The per-second coding data is equally divided based on the rate of the flashing coding, and a plurality of time slots are obtained correspondingly; The first n bytes of the per-second coding data are set as the fixed coding bits, the last m bytes of the per-second coding data are set as the check bits, and the remaining bytes are set as the number information of the obstruction light, so as to control the obstruction light to perform the flashing coding control.

[0010] Further, the decoding processing is performed based on the collected video stream to obtain the number information of the obstruction light, comprising: The image color space transformation is performed on the collected video stream through the transformation algorithm; Based on the result of the image color space transformation, the segmentation algorithm is adopted to perform the segmentation processing on the video stream, so as to screen the candidate obstruction light matched with the preset light-emitting color; The IMU data of the flight control module of the unmanned aerial vehicle is obtained, and the candidate obstruction light is calibrated and fused in combination with the IMU data, so as to aggregate the light point set and the corresponding light point trajectory.

[0011] Further, the decoding processing is performed based on the collected video stream to obtain the number information of the obstruction light, further comprising: The decoding processing is performed on the video stream to obtain the coding information of the obstruction light in the video stream; According to the encoding information of the aviation obstruction light in the video stream, a target aviation obstruction light with the encoding information is extracted from the light point set.

[0012] Further, the corresponding position information is determined according to the number information, and the positioning information of the unmanned aerial vehicle is acquired according to the position information, including: The number of light point positions of the target aviation obstruction light is acquired. When the number of light point positions is 1, the positioning information calculation of the unmanned aerial vehicle is performed based on the position information by using the aperture ranging method. When the number of light point positions is 2, the positioning information calculation of the unmanned aerial vehicle is performed based on the position information by using the binocular ranging method. When the number of light point positions is greater than 2, the positioning information calculation of the unmanned aerial vehicle is performed based on the position information by using the three-point positioning method.

[0013] Further, it further includes: Based on the positioning information, the flight trajectory of the unmanned aerial vehicle is regulated and controlled by the EKL processing algorithm.

[0014] The embodiment of the application also provides an unmanned aerial vehicle positioning system based on aviation obstruction lights, which is suitable for the unmanned aerial vehicle positioning method based on aviation obstruction lights according to any one of the above, and the system includes a parameter configuration platform, a light subsystem and an unmanned aerial vehicle subsystem, wherein: The parameter configuration platform is used for sending aviation obstruction light information to the light subsystem and the unmanned aerial vehicle subsystem respectively; wherein the aviation obstruction light information includes number information and position information of the aviation obstruction light; The light subsystem is used for controlling the aviation obstruction light to flash code according to the number information. The unmanned aerial vehicle subsystem is used for collecting video streams of the aviation obstruction light; decoding processing is performed based on the collected video streams to obtain the number information of the aviation obstruction light; the corresponding position information is determined according to the number information, and the positioning information of the unmanned aerial vehicle is acquired according to the position information.

[0015] Further, the light subsystem includes: A communication module is used for communicating with the parameter configuration platform. A light control module is connected with the communication module and the aviation obstruction light respectively, and is used for data transmission with the communication module and control of the aviation obstruction light to flash code. A GPS module is connected with the light control module, and is used for timing control of the light control module.

[0016] Further, the unmanned aerial vehicle subsystem includes: The video acquisition module is configured to acquire a video stream of the aeronautical obstacle light. The positioning module is connected to the video acquisition module and configured to perform positioning calculation on the unmanned aerial vehicle based on the acquired video stream.

[0017] The embodiment of the present application provides a positioning method and system for an unmanned aerial vehicle based on an aeronautical obstacle light. The method is applied to an unmanned aerial vehicle positioning system, which comprises a parameter configuration platform, a light subsystem and an unmanned aerial vehicle subsystem. The method comprises the following steps: the parameter configuration platform sends aeronautical obstacle light information to the light subsystem and the unmanned aerial vehicle subsystem respectively; the aeronautical obstacle light information comprises number information and position information of the aeronautical obstacle light; the light subsystem controls the aeronautical obstacle light to perform flashing coding according to the number information; the unmanned aerial vehicle subsystem acquires a video stream of the aeronautical obstacle light; decoding processing is performed based on the acquired video stream to obtain the number information of the aeronautical obstacle light; the corresponding position information is determined according to the number information, and the positioning information of the unmanned aerial vehicle is obtained according to the position information. In the embodiment of the present application, the parameter configuration platform sends the number information to the light subsystem first, and the light subsystem controls the aeronautical obstacle light to perform flashing coding according to the received number information. At the same time, the unmanned aerial vehicle subsystem acquires a video stream of the flashing of the aeronautical obstacle light, and performs decoding processing on the acquired video stream, so as to extract the number information of the aeronautical obstacle light. Then, the corresponding position information is determined based on the decoded number information, and the positioning of the unmanned aerial vehicle is realized according to the position information. In this way, the problems of low positioning accuracy and easy interference in the traditional positioning method can be effectively avoided. The aeronautical obstacle light is used as a positioning beacon, which is not affected by environmental interference such as building shielding and electromagnetic interference, and can provide high positioning accuracy. At the same time, the method has controllable cost and is suitable for large-scale commercial flight scenarios, which provides a strong guarantee for the safe development of low-altitude economy. BRIEF DESCRIPTION OF DRAWINGS

[0018] In order to more clearly illustrate the technical solutions of the embodiments of the present application, the following will briefly introduce the drawings needed to be used in the embodiment description. Obviously, the drawings in the following description are some embodiments of the present application, and other drawings can also be obtained by those skilled in the art without creating laborious work.

[0019] Figure 1 A flowchart of a positioning method for an unmanned aerial vehicle based on an aeronautical obstacle light is provided for the embodiment of the present application. Figure 2 A frame structure example diagram of a positioning method for an unmanned aerial vehicle based on an aeronautical obstacle light is provided for the embodiment of the present application. Figure 3Another flowchart of a method for positioning a UAV based on an aviation obstruction light according to an embodiment of the present application is provided. Figure 4 A system architecture diagram of a UAV positioning system based on an aviation obstruction light according to an embodiment of the present application is provided. Figure 5 A subsystem architecture diagram of a UAV positioning system based on an aviation obstruction light according to an embodiment of the present application is provided. Figure 6 Another subsystem architecture diagram of a UAV positioning system based on an aviation obstruction light according to an embodiment of the present application is provided. DETAILED DESCRIPTION

[0020] The technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the drawings in the embodiments of the present application. Obviously, the described embodiments are only some of the embodiments of the present application, rather than all the embodiments of the present application. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without creative efforts fall within the scope of the present application.

[0021] It should be understood that, when used in the specification and the appended claims, the terms "comprise" and "include" indicate the presence of the described features, integers, steps, operations, elements, and / or components, but do not exclude one or more other features, integers, steps, operations, elements, components, and / or groups thereof.

[0022] It should also be understood that the terms used in the present application specification are only for the purpose of describing particular embodiments and are not intended to limit the present application. As used in the present application specification and the appended claims, the singular forms "a", "an" and "the" are intended to include the plural forms unless the context clearly indicates otherwise.

[0023] It should be further understood that the term "and / or" used in the present application specification is intended to refer to any combination of one or more of the associated listed items and all possible combinations thereof.

[0024] Please see Figure 1 The method for positioning a UAV based on an aviation obstruction light provided by the embodiments of the present application is applied to a UAV positioning system, the UAV positioning system comprises a parameter configuration platform, a light subsystem and a UAV subsystem, and the method comprises steps S101-S105.

[0025] In step S101, the parameter configuration platform sends aviation obstruction light information to the light subsystem and the UAV subsystem respectively; wherein the aviation obstruction light information comprises number information and position information of the aviation obstruction light. Step S102, the light subsystem controls the aviation obstruction light to flash code according to the numbering information; Step S103, the unmanned aerial vehicle subsystem collects video stream of the aviation obstruction light; Step S104, decodes the collected video stream to obtain the numbering information of the aviation obstruction light; Step S105, determines the corresponding position information according to the numbering information, and obtains the positioning information of the unmanned aerial vehicle according to the position information.

[0026] In this embodiment, first, the parameter configuration platform sends numbering information to the light subsystem, and the light subsystem controls the aviation obstruction light to flash code according to the received numbering information. At the same time, the unmanned aerial vehicle subsystem collects the video stream of the aviation obstruction light flashing, and decodes the collected video stream to extract the numbering information of the aviation obstruction light. Then, based on the decoded numbering information, the corresponding position information can be determined according to the numbering information, and the positioning of the unmanned aerial vehicle can be realized according to the position information. In this way, the problems of low positioning accuracy and easy interference in traditional positioning methods can be effectively avoided. Using aviation obstruction lights as positioning beacons not only avoids environmental interference such as building obstruction and electromagnetic interference, but also provides high positioning accuracy. At the same time, the method is cost controllable and suitable for large-scale commercial flight scenarios, providing a strong guarantee for the safe development of low-altitude economy.

[0027] This embodiment is based on visible light visual positioning technology (VLP), and uses aviation obstruction lights on high-rise buildings and obstacles in cities as positioning beacons. The aviation obstruction light emits light-carrying coded information, and the unmanned aerial vehicle provides a low-cost redundant high-precision positioning method through visual communication and visual positioning technology, AI target recognition technology, and multi-modal perception and positioning tracking fusion technology, greatly improving the safety and reliability of flight. Compared with traditional satellite navigation or radio positioning technology, the high-precision visual positioning technology based on light guidance relies on positioning indicator lights arranged in advance at specific positions on the ground. The positioning method provided in this embodiment can effectively avoid the problem of satellite navigation being blocked by buildings in a specific environment, and eliminates the complexity of competing for frequency bands with wireless communication. Even if it encounters accidental or malicious radio interference, this technology is not affected. In addition, the visual positioning of light guidance also integrates visual visible light communication technology, thereby significantly improving the positioning accuracy and meeting the positioning needs of low-altitude flight.

[0028] In an embodiment, the unmanned aerial vehicle positioning method based on aviation obstruction lights further comprises: Timing synchronization control of the flash code and video stream collection based on PPS signals.

[0029] The embodiment synchronizes the flashing encoding process of the aviation obstruction light and the video stream acquisition process of the UAV subsystem based on the high-precision timing characteristics of the PPS (Pulse Per Second) signal. Specifically, the PPS signal is introduced into the light subsystem and the UAV subsystem as a unified time reference: in the light subsystem, the PPS signal triggers the starting time of the flashing encoding, ensuring that the generation of the encoding data per second is strictly aligned with the second pulse; in the UAV subsystem, the starting time of frame capture is calibrated according to the PPS signal, so that the acquisition time of each frame of video is accurately synchronized with the time slot boundary of the flashing encoding. Through this timing synchronization mechanism, the misalignment problem of encoding and acquisition caused by system clock deviation or transmission delay can be effectively eliminated, such as avoiding the encoding data across time slot disorder caused by clock drift, or the complete encoding period missing caused by acquisition delay.

[0030] Here, since there is no direct communication between the light subsystem and the UAV subsystem described in the embodiment, the starting point of the time slot decoding is set to PPS (Pulse Per Second). Therefore, it is required to calculate the first frame starting from the integer second of PPS each time. For a 240 frame / s camera, the duration of each frame is 4.2 ms, and this signal is accurate enough for synchronization.

[0031] In an embodiment, the light subsystem controls the aviation obstruction light to perform flashing encoding control according to the numbering information, including: Obtaining the rate of video stream acquisition of the UAV subsystem, and setting the rate of flashing encoding according to the rate of video stream acquisition; Based on the rate of flashing encoding, the encoding data per second is equally divided to obtain a plurality of time slots; Setting the first n bytes of the encoding data per second as fixed encoding bits, setting the last m bytes of the encoding data per second as check bits, and setting the remaining bytes as the numbering information of the aviation obstruction light, so as to control the aviation obstruction light to perform flashing encoding control.

[0032] The embodiment dynamically adjusts the flashing coding rate of the aeronautical obstacle light by the rate of the video stream collected by the unmanned aerial vehicle subsystem, and ensures that the coding information is strictly matched with the video collection frame rate. In the specific operation, the light subsystem first receives the real-time collection frame rate parameter fed back by the unmanned aerial vehicle subsystem. For example, when the video stream is transmitted at 30 frames per second, the system splits the coding period per second into 30 equal time slots, and each time slot corresponds to a collection window of one frame of video. In the coding structure design, a three-section coding framework of "fixed bit + data bit + check bit" is adopted: the first n bytes are used as fixed coding bits to identify the light control protocol version and the system working mode; the middle byte carries the unique number information of the aeronautical obstacle light; and the last m bytes are set as check (CRC) bits to detect data errors in the video transmission. This dynamic time slot allocation mechanism not only solves the time sequence misalignment problem of coding and collection in the high-speed motion scene, but also significantly improves the reliability of data transmission through the check bit design, and provides a structured data basis for subsequent accurate decoding.

[0033] For example, it is assumed that the camera of the unmanned aerial vehicle collects images at a speed of 240 frames, and the corresponding light subsystem flashes at a rate of 240 bits / s. Generally, it is assumed that the light subsystem is on when it represents 1, and the light subsystem is off when it represents 0. Figure 2 For 240 bits of data per second, it can be split into 10 equal parts, each of which is called a time slot. That is, 24 bits of data can be sent every 100 ms, of which the first 6 bits are fixed as 101010, which is used as the leading data of the frame. That is, the light flashes three times at the beginning of each time slot, which can exclude most irrelevant light interference. The next 16 bits are used to store the number information of the light subsystem, and the last two bits are used for checking, which can use CRC-2 algorithm or other checking algorithm in actual application.

[0034] Based on this, the unmanned aerial vehicle can obtain the number information of the ground light within 100 milliseconds in each time slot if the decoding is successful. The number corresponding to the light position information has been pre-collected and stored in the parameter configuration platform after the system is installed. Each subsystem can obtain these information from the platform through communication means. These basic information includes three-dimensional coordinate information, true height information and ID number information (x, y, z, h, id) of the light, wherein x, y and z represent the position in the world coordinate system, and h represents the true height information of the light. In other words, when the unmanned aerial vehicle successfully decodes the data in a time slot, the position information of the corresponding light can be obtained. If the data of three lights can be obtained at any time point, the position information of the camera of the unmanned aerial vehicle at this time can be calculated.

[0035] In an embodiment, the decoding processing based on the collected video stream to obtain the number information of the aeronautical obstacle light comprises: The collected video stream is subjected to image color space transformation through a transformation algorithm; Based on the result of image color space transformation, a segmentation algorithm is used to segment the video stream, so as to screen the candidate aviation obstruction light matching the preset light-emitting color; IMU data of the flight control module of the unmanned aerial vehicle are acquired, and the candidate aviation obstruction light is calibrated and fused in combination with the IMU data, so as to aggregate the light point set and the corresponding light point trajectory.

[0036] Further, the collected video stream is subjected to decoding processing to obtain the number information of the aviation obstruction light, and the method further comprises: The video stream is subjected to decoding processing to obtain the coding information of the aviation obstruction light in the video stream; The target aviation obstruction light with coding information is extracted from the light point set according to the coding information of the aviation obstruction light in the video stream.

[0037] The embodiment needs to quickly process each frame of image of the collected video stream, generally through HSV image color space transformation (if performance needs to be improved, a special chip can be directly used to realize the transformation), and through a segmentation algorithm such as filtering binarization to find the candidate aviation obstruction light matching the preset light-emitting color, for example, a red light-emitting point. Then, the calibration and fusion are performed in combination with the IMU data of the flight control to aggregate into a light point set {L i}, and form a light point trajectory {T i}.

[0038] Here, when the GPS signal is disturbed and invalid, the flight control module can calculate the PPS time by means of the self-crystal oscillator, output a pseudo-PPS signal in a short time, and maintain the accuracy of the system. In this way, the on-off information of the light can be strictly calculated, and each bit can be solved. Since the unmanned aerial vehicle is continuously in a motion state, the on-off relationship is determined through the following algorithm.

[0039] Suppose the aviation obstruction light is red, the unmanned aerial vehicle is located about 100 meters above the light, and the image resolution collected is 1920x1080, that is, 2 million pixels, and the focal length is about 40 millimeters. According to this, each pixel corresponds to about 0.1 meters. Assuming that the flight speed of the unmanned aerial vehicle is 10 meters per second, the position of the next frame of image basically remains unchanged under high-speed collection of 240 frames per second.

[0040] In the light point trajectory calculation, if the predetermined position detects the light point, it is marked as 1 at this time. When the next frame image is acquired, since the flight control attitude information (such as Euler angle, position, flight speed and direction) can be acquired from the flight control module, it can be calibrated to the position of the previous frame, and only needs to search in the area near the last light point. If the light point cannot be detected, it is considered that the light point has been extinguished, and it is marked as 0. In actual application, assuming that the height of the aviation obstruction light is about 100 meters, the adjacent area of the aviation obstruction light can be simply defined as a circular area with a radius of 20 pixels near the current point. A more optimized method is to set the adjacent area as a semi-ellipse along the flight direction, for example, the major axis radius of the ellipse is 20 pixels, and the minor axis radius is 10 pixels. This way can effectively reduce the calculation amount and improve the processing speed.

[0041] For the generated light point trajectory Where i represents the ith light, j represents the jth flashing time, and in a time slot, the flashing code is calculated by the time difference .

[0042] As described above, the frame structure design can effectively screen out the real candidate light points after 6 frames of processing. Since the interference light sources (such as car taillights, upward shining flashlights, laser pens and background light lamps) in real life are almost impossible to flash according to a specific rule at the time point of PPS synchronization, therefore at this stage, most of the interference light points have been excluded.

[0043] In an embodiment, the position information corresponding to the number information is determined according to the number information, and the positioning information of the unmanned aerial vehicle is acquired according to the position information, including: The number of light point positions of the target aviation obstruction light is acquired; When the number of light point positions is 1, the positioning information of the unmanned aerial vehicle is calculated based on the position information by using the aperture ranging method; When the number of light point positions is 2, the positioning information of the unmanned aerial vehicle is calculated based on the position information by using the binocular ranging method; When the number of light point positions is greater than 2, the positioning information of the unmanned aerial vehicle is calculated based on the position information by using the three-point positioning method.

[0044] ​The embodiment adopts a differentiated positioning strategy based on the number of light points of the target aviation obstacle light. When only a single light point is detected, a light circle ranging mode is adopted to realize positioning. The mode reverses the straight-line distance between the unmanned aerial vehicle and the light by analyzing the light halo radius formed by the light in the image, combining the known actual physical size of the light and the focal length parameter, and using the geometric projection principle. Specifically, by measuring the distance from the halo edge pixel to the center point, and combining the pixel-angle mapping table established by the camera calibration parameters, the line-of-sight angle can be accurately calculated, and then the spatial distance can be calculated by the trigonometric function.

[0045] When two light points are detected, a binocular ranging mode is adopted to realize positioning. The mode calculates the relative height of the unmanned aerial vehicle and the light plane by comparing the position offset of the two lights in the image, combining the known baseline distance of the two lights (obtained through the parameter configuration platform), and using the parallax ranging principle. In actual calculation, the synchronization acquisition time sequence of the two cameras can be calibrated first to ensure the validity of the parallax data; then the accurate coordinates of the two lights in their respective images are determined through a feature point matching algorithm; finally, the spatial position of the unmanned aerial vehicle is calculated by constructing a three-dimensional coordinate system according to the stereo vision principle.

[0046] When three or more light points are detected, a three-point positioning mode is adopted to realize positioning. The mode uses the least squares method to optimize and fit multiple light points, and solves the optimal spatial coordinates of the unmanned aerial vehicle by constructing an over-determined equation set. In specific implementation, the three light points with the strongest signal strength can be selected as the reference first; then a spatial geometric relationship model is established according to the known three-dimensional coordinates (x, y, z) of each light and the relative angle observed by the unmanned aerial vehicle; finally, the error between the observed value and the predicted value is minimized through an iterative optimization algorithm (such as the Levenberg-Marquardt algorithm), and the accurate position of the unmanned aerial vehicle is finally determined.

[0047] This multi-source data fusion positioning method not only significantly improves the positioning accuracy, but also enhances the anti-interference ability of the system through redundancy design. Even if individual lights are blocked or fail, the remaining lights can still complete the positioning calculation.

[0048] For example, taking the three-point positioning method as an example: Camera model: Establish a pinhole camera model, and the conversion relationship between the three-dimensional coordinates of the light source and the image coordinates is: wherein, is the camera intrinsic matrix (which needs to be calibrated in advance, including focal length, principal point coordinates, etc.), is the camera extrinsic matrix (rotation and translation, representing the pose of the camera in the world coordinate system). ​​​

[0049] The positioning step comprises: firstly knowing the world coordinates of at least 3 light sources And the corresponding image coordinates The origin of the general world coordinate system is set at the airport take-off point. Then a linear equation set is established, and the world coordinates of the camera optical center , that is, the user's own position.

[0050] Assuming that there is only one light point, and the reference point true height is , then the true height is .

[0051] Here, if the reference point found by the light is 2, the weighted average of the two reference points is calculated , and the true height is ; if the number of reference points found is greater than 3, the nearest three reference points are selected, and the weighted average is calculated + , and the true height is .

[0052] In an embodiment, the unmanned aerial vehicle positioning method based on the aviation obstruction light further comprises: Based on the positioning information, the flight trajectory of the unmanned aerial vehicle is regulated by an EKL processing algorithm.

[0053] After the positioning of the unmanned aerial vehicle is realized, the flight trajectory of the unmanned aerial vehicle can be dynamically regulated by the EKL processing algorithm. Specifically, Figure 3 After the positioning information is obtained based on the aviation obstruction light, the IMU data of the flight control module and other positioning results, such as satellites, base stations, etc., are combined and input into the EKL model, and the corresponding flight trajectory prediction result is output by the EKL model, so as to regulate the flight trajectory of the unmanned aerial vehicle.

[0054] Figure 4 A system architecture diagram of an unmanned aerial vehicle positioning system based on an aviation obstruction light is provided for the embodiment of the present application. The system is suitable for the unmanned aerial vehicle positioning method based on the aviation obstruction light as described above. The system comprises a parameter configuration platform 100, a light subsystem 200 and an unmanned aerial vehicle subsystem 300, wherein: The parameter configuration platform 100 is used to send aviation obstruction light information to the light subsystem 200 and the unmanned aerial vehicle subsystem 300 respectively; wherein the aviation obstruction light information comprises number information and position information of the aviation obstruction light; The light subsystem 200 is used to control the aviation obstruction light to flash code according to the number information; The UAV subsystem 300 is used to acquire video streams of the aviation obstruction lights; decode the acquired video streams to obtain the numbering information of the aviation obstruction lights; determine the corresponding location information based on the numbering information; and obtain the UAV's positioning information based on the location information.

[0055] The UAV positioning system described in this embodiment includes a parameter configuration platform 100, a lighting subsystem 200, and a UAV subsystem 300. In application, the parameter configuration platform 100 first sends a numbering information to the lighting subsystem 200. The lighting subsystem 200 then controls the aviation obstruction lights to flash according to the received numbering information. Simultaneously, the UAV subsystem 300 captures a video stream of the flashing aviation obstruction lights and decodes the stream to extract the numbering information. Based on this decoded information, the UAV's positioning information is obtained. This effectively avoids the problems of low positioning accuracy and susceptibility to interference found in traditional positioning methods. Using aviation obstruction lights as positioning beacons is not only unaffected by environmental interference such as building obstructions and electromagnetic interference, but also provides high positioning accuracy. Furthermore, this method is cost-effective and suitable for large-scale commercial flight scenarios, providing strong support for the safe development of the low-altitude economy. Here, the parameter configuration platform 100 is the central hub of the UAV positioning system, and it can interact with the lighting subsystem 200 and the UAV subsystem 300 through communication interfaces. The parameter configuration platform 100 can simultaneously send information such as the lighting system's ID, location (x, y, z), true altitude h, encryption key K, and encryption algorithm A to both the lighting subsystem 200 and the UAV subsystem 300. Encryption algorithm A is global information; the entire system uses the same encryption algorithm mechanism.

[0056] In one embodiment, such as Figure 5 As shown, the lighting subsystem 200 includes: A communication module is used to communicate and interact with the parameter configuration platform 100. The lighting control module is connected to the communication module and the aviation obstruction lights respectively, and is used to transmit data with the communication module and control the aviation obstruction lights to perform flashing encoding; The GPS module is connected to the lighting control module and is used for timing control of the lighting control module.

[0057] The lighting subsystem 200 described in this embodiment includes a lighting control module, a GPS module, LED lights (i.e., aviation obstruction lights), and a communication module. The lighting subsystem 200 communicates with the parameter configuration platform via the communication module. The lighting control module is the core of the lighting subsystem 200; it operates according to predetermined parameters sent by the parameter configuration platform 100. These parameters mainly include the module's identification number. This number is uniformly assigned by the parameter configuration platform to ensure that each lighting subsystem 200 has a unique identification number. The lighting control module controls the LED lights to flash in a coded manner, which is synchronized based on the PPS pin information of the GPS module. Furthermore, the GPS module can periodically provide information such as time and location. For example, location information can be used to determine whether the lighting subsystem 200 is fixed in its original position; if the device moves, an alarm signal can be sent. Time information can be used for further encryption of the coded information, such as periodically changing the coded data according to time, thereby improving system security and preventing malicious actors from forging the lighting system.

[0058] In one embodiment, such as Figure 6 As shown, the unmanned aerial vehicle (UAV) subsystem 300 includes: The video acquisition module is used to acquire video streams from the aviation obstruction lights; The positioning module, connected to the video acquisition module, is used to perform positioning calculations on the drone based on the acquired video stream.

[0059] The UAV subsystem 300 mainly includes a video acquisition module and a positioning module. Under the control of the positioning module, the video acquisition module is responsible for synchronously acquiring video streams from aviation obstruction lights; the positioning module processes the video streams to obtain real-time UAV positioning information. A key aspect of this process for the UAV subsystem 300 is communication with the flight control module to obtain real-time attitude control information for the UAV. Furthermore, information from the parameter configuration platform 100 also needs to be transmitted to the positioning module via the flight control module. To achieve synchronous acquisition by the video acquisition module, it is necessary to obtain the PPS pin signal from the flight control module. Since most UAVs use GPS as their reference positioning method, and the GPS module is a built-in device, the flight control module can obtain the PPS signal from the GPS module.

[0060] The various embodiments in this specification are described in a progressive manner, with each embodiment focusing on its differences from other embodiments. Similar or identical parts between embodiments can be referred to interchangeably. For the systems disclosed in the embodiments, since they correspond to the methods disclosed in the embodiments, the descriptions are relatively simple; relevant parts can be referred to in the method section. It should be noted that those skilled in the art can make various improvements and modifications to this application without departing from the principles of this application, and these improvements and modifications also fall within the protection scope of the claims of this application.

[0061] It should also be noted that, in this specification, relational terms such as "first" and "second" are used only to distinguish one entity or operation from another, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Furthermore, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or apparatus. Without further limitations, an element defined by the phrase "comprising one..." does not exclude the presence of other identical elements in the process, method, article, or apparatus that includes said element.

Claims

1. A UAV positioning method based on aviation obstruction lights, applied to a UAV positioning system, the UAV positioning system comprising a parameter configuration platform, a lighting subsystem, and a UAV subsystem, characterized in that, The method includes: The parameter configuration platform sends aviation obstruction light information to the lighting subsystem and the UAV subsystem respectively; wherein, the aviation obstruction light information includes the number and location information of the aviation obstruction light; The lighting subsystem controls the aviation obstruction lights to flash according to the numbering information; The unmanned aerial vehicle subsystem acquires video streams of the aviation obstruction lights; The acquired video stream is decoded to obtain the numbering information of the aviation obstruction light; The corresponding location information is determined based on the number information, and the drone's positioning information is obtained based on the location information.

2. The UAV positioning method based on aviation obstruction lights according to claim 1, characterized in that, Also includes: Timing synchronization control of the flicker encoding and video stream acquisition is performed based on the PPS signal.

3. The UAV positioning method based on aviation obstruction lights according to claim 1, characterized in that, The lighting subsystem controls the aviation obstruction lights to perform flashing code control based on the numbering information, including: Obtain the video stream acquisition rate of the UAV subsystem, and set the flashing encoding rate according to the video stream acquisition rate; Based on the rate of flash coding, the coded data per second is divided into equal parts to obtain multiple time slots; The first n bytes of the encoded data per second are set as fixed encoding bits, the last m bytes of the encoded data per second are set as check bits, and the remaining bytes are set as the number information of the aviation obstruction light, thereby controlling the aviation obstruction light to perform flashing encoding control.

4. The UAV positioning method based on aviation obstruction lights according to claim 1, characterized in that, The decoding process based on the acquired video stream to obtain the numbering information of the aviation obstruction light includes: The acquired video stream is transformed using a transformation algorithm to convert its color space. Based on the results of image color space transformation, a segmentation algorithm is used to segment the video stream, thereby filtering out candidate aviation obstruction lights that match the preset emission color. The IMU data of the UAV's flight control module is acquired, and the candidate aviation obstruction lights are calibrated and fused in combination with the IMU data to obtain a set of light locations and corresponding light location trajectories.

5. The UAV positioning method based on aviation obstruction lights according to claim 4, characterized in that, The decoding process based on the acquired video stream to obtain the numbering information of the aviation obstruction light also includes: The video stream is decoded to obtain the encoded information of the aviation obstruction lights in the video stream; Based on the encoded information of the aviation obstruction lights in the video stream, target aviation obstruction lights with encoded information are extracted from the set of light locations.

6. The UAV positioning method based on aviation obstruction lights according to claim 5, characterized in that, The step of determining the corresponding location information based on the number information and obtaining the UAV's positioning information based on the location information includes: Obtain the number of light points of the target aviation obstruction light; When the number of light points is 1, the drone's positioning information is calculated using the aperture ranging method based on the location information. When the number of light points is 2, the positioning information of the UAV is calculated using a binocular ranging method based on the location information. When the number of light points is greater than 2, the three-point positioning method is used to calculate the positioning information of the UAV based on the location information.

7. The UAV positioning method based on aviation obstruction lights according to claim 1, characterized in that, Also includes: Based on the positioning information, the flight trajectory of the UAV is controlled by the EKL processing algorithm.

8. A drone positioning system based on aviation obstruction lights, applicable to the drone positioning method based on aviation obstruction lights as described in any one of claims 1-7, characterized in that, The system includes a parameter configuration platform, a lighting subsystem, and a drone subsystem, wherein: The parameter configuration platform is used to send aviation obstruction light information to the lighting subsystem and the UAV subsystem respectively; wherein, the aviation obstruction light information includes the number and location information of the aviation obstruction light; The lighting subsystem is used to control the aviation obstruction lights to flash according to the numbering information; The UAV subsystem is used to acquire video streams of the aviation obstruction lights; decode the acquired video streams to obtain the numbering information of the aviation obstruction lights; determine the corresponding location information based on the numbering information; and obtain the UAV's positioning information based on the location information.

9. The UAV positioning system based on aviation obstruction lights according to claim 8, characterized in that, The lighting subsystem includes: A communication module is used for communication and interaction with the parameter configuration platform; The lighting control module is connected to the communication module and the aviation obstruction lights respectively, and is used to transmit data with the communication module and control the aviation obstruction lights to perform flashing encoding; The GPS module is connected to the lighting control module and is used for timing control of the lighting control module.

10. The UAV positioning system based on aviation obstruction lights according to claim 8, characterized in that, The unmanned aerial vehicle (UAV) subsystem includes: The video acquisition module is used to acquire video streams from the aviation obstruction lights; The positioning module, connected to the video acquisition module, is used to perform positioning calculations on the drone based on the acquired video stream.

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