Low-altitude aircraft detection real-time analysis method based on three-dimensional space data

Abstract

The invention discloses a low-altitude aircraft detection real-time analysis method based on three-dimensional space data, and the method comprises the following steps: S1, setting the number of stages of an earth space grid, carrying out the grid division of a region, and storing the predicted basic altitude data in a divided bottom grid; s2, acquiring flight parameters of the low-altitude aircraft by using a low-altitude detection device; s3, calculating the real-time basic altitude of the low-altitude aircraft according to the real-time latitude and longitude of the unmanned aerial vehicle S4, judging whether the low-altitude aircraft flies normally or abnormally according to flight supervision requirements of the low-altitude aircraft; and S5, executing a low-altitude aircraft supervision program according to the judgment result of normal flight or abnormal flight. The three-dimensional space data-based low-altitude aircraft detection real-time analysis method has the characteristics of data space saving, rapid calculation response and real-time comprehensive supervision.

Description

Technical Field

[0001] The invention relates to a low-altitude aircraft detection method, in particular to a low-altitude aircraft detection real-time analysis method based on three-dimensional spatial data. Background Art

[0002] According to the Interim Regulations on the Management of Unmanned Aerial Vehicle Flights, the flight altitude of low-altitude aircraft in suitable airspace is limited to a "true altitude" of 120 meters, that is, the vertical height between the low-altitude aircraft and the ground does not exceed 120 meters. If the low-altitude aircraft operator flies a low-altitude aircraft on high ground such as buildings or mountains, this "true altitude" is calculated relative to the surface altitude of the take-off point.

[0003] Suitable airspace refers to areas that are not designated as controlled airspace. Micro, light, and small low-altitude aircraft (such as agricultural low-altitude aircraft) are allowed to fly within a true altitude of no more than 120 meters without prior application or approval. However, flying in airspace above 120 meters or in controlled airspace requires approval from the air traffic management department. Controlled airspace includes special sensitive areas such as airport perimeters and military restricted areas, as well as all airspace with a true altitude of more than 120 meters. Flying in such airspace is not allowed without permission.

[0004] Under the existing technology, low-altitude aircraft detection methods can sometimes only detect the aircraft's altitude or relative height to the remote control, and cannot detect the aircraft's true height in real time. Or the algorithm requires too much storage data and the calculation complexity is high, which brings some difficulties to the real-time supervision and precise implementation of the "Interim Regulations on Unmanned Aircraft Flight Management". Therefore, a new type of real-time analysis method for low-altitude aircraft detection is needed. Summary of the invention

[0005] In order to strengthen the supervision of low-altitude aircraft, the present invention provides a low-altitude aircraft detection real-time analysis method based on three-dimensional spatial data, comprising the following steps: S1. Set the geospatial grid level, divide the area into grids, and store the predicted basic altitude data in the divided bottom grids; S2. Use low-altitude detection equipment to obtain flight parameters of low-altitude aircraft; S3. Calculate the real-time basic altitude of low-altitude aircraft based on the real-time latitude and longitude of the UAV; S4. Determine whether the flight of a low-altitude aircraft is normal or abnormal according to the flight supervision requirements of low-altitude aircraft; S5. Execute low-altitude aircraft supervision procedures based on the judgment results of normal or abnormal flight.

[0006] Preferably, the step S1 further comprises: using a quadtree to store the earth space grid.

[0007] Preferably, step S2 comprises: 1) Use interactive methods to establish communication connections with low-altitude aircraft and obtain flight parameters of low-altitude aircraft; 2) Use non-interactive methods to obtain flight parameters of low-altitude aircraft; The flight parameters include basic flight parameters and extended flight parameters; the basic flight parameters include low-altitude aircraft identification code, low-altitude aircraft position latitude, low-altitude aircraft position longitude, and low-altitude aircraft altitude; the extended flight parameters include: low-altitude aircraft type, take-off status, heading angle, low-altitude aircraft horizontal speed, low-altitude aircraft vertical speed, low-altitude aircraft pressure altitude, operator position latitude, and operator position longitude.

[0008] Preferably, the interaction is achieved through a remote identification (Remote ID) protocol.

[0009] Preferably, step S3 comprises: 1) Based on the longitude and latitude of the low-altitude aircraft, the quadtree query method is used to recursively search the nodes of the quadtree to find the bottom-level blocks; 2) Use the Euclidean distance formula to calculate the distance between the longitude and latitude of the low-altitude aircraft and each longitude and latitude data in the bottom block to find the point with the shortest distance; 3) The real-time basic altitude of low-altitude aircraft is obtained through the mapping of longitude and latitude to basic altitude.

[0010] Preferably, the non-interactive method includes: 1) Radar measurement method: Use radar to transmit radar waves to low-altitude aircraft and receive the reflected signals. By calculating the time difference or phase difference of the round-trip radar waves, the aircraft's flight altitude and flight longitude and latitude can be calculated; 2) Multi-point positioning method: multiple low-altitude detection devices are set up on the ground, and the aircraft's flight altitude and flight longitude and latitude are determined by measuring the signal propagation time difference or phase difference between the low-altitude detection device and the aircraft.

[0011] Preferably, step S4 comprises: S41. Determine whether the flight is abnormal based on the low-altitude aircraft identification code; S42. Determine whether the low-altitude aircraft belongs to the control area based on its longitude and latitude; S43. Calculate the true flight altitude based on the flight latitude and longitude and the flight altitude of the low-altitude aircraft; S44. When the true flight altitude exceeds the true altitude limit, a flight check is performed.

[0012] Preferably, the flight anomaly includes unregistered identification code, flight in a controlled area, unreported flight at excessive altitude, abnormal flight reporting time, and abnormal flight reporting altitude; The flight verification includes: 1) For low-altitude aircraft with known identification codes, check whether the flight has been reported; for low-altitude aircraft with unknown identification codes, check whether there is a flight report in the area; 2) If there is no flight report, it is judged as flight abnormality and the reason value is "over-altitude flight not reported"; if there is a flight report, check whether the current flight time is within the flight report time range. If not, it is judged as flight abnormality and the reason value is "flight report time abnormality"; if the flight report time is normal, check whether the flight longitude and latitude and true flight altitude are within the flight report space range. If they are beyond the range, it is judged as flight abnormality and the reason value is "flight report altitude abnormality".

[0013] Preferably, step S5 comprises: S51, recording the flight data of the low-altitude aircraft and storing it in a database; S52. In case of abnormal flight, issue a warning to the operator of low-altitude aircraft to inform him of the abnormal flight; S53. If the abnormal behavior of a low-altitude aircraft poses a serious safety hazard, it shall be immediately restricted or prohibited from continuing to fly.

[0014] The present invention has the following beneficial effects: 1) The national standard method is used to establish the correspondence between the earth space grid code and the basic altitude, which has good versatility and transplantability.

[0015] 2) A quadtree is used to store the correspondence between the earth's spatial grid code and the basic altitude, which greatly compresses the storage space.

[0016] 3) Based on quadtree index query and Euclidean distance formula, the true height of the nearest point is quickly calculated.

[0017] 4) The low-altitude detection device is used to obtain the identification code, flight longitude and latitude of low-altitude aircraft, and based on the calculation of the true height of the low-altitude aircraft, the flight and flight reporting verification are judged, which is fast, efficient and widely applicable.

[0018] The present invention discloses a real-time analysis method for low-altitude aircraft detection based on three-dimensional spatial data, which has the characteristics of saving data space, rapid calculation response and real-time comprehensive supervision. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Figure 1 This is a step diagram of a real-time analysis method for low-altitude aircraft detection based on three-dimensional spatial data according to an embodiment of the present invention; Figure 2This is a calculation logic diagram of a real-time analysis method for low-altitude aircraft detection based on three-dimensional spatial data in an embodiment of the present invention when the identification code is known. DETAILED DESCRIPTION

[0020] In order to further understand the present invention, preferred embodiments of the present invention are described below in conjunction with examples. However, it should be understood that these descriptions are only for further illustrating the features and advantages of the present invention, rather than limiting the claims of the present invention.

[0021] The present invention provides a real-time analysis method for low-altitude aircraft detection based on three-dimensional spatial data, such as Figure 1 As shown, the following steps are included: S1. Set the earth space grid level, divide the area into grids, and store the predicted basic altitude data in the divided bottom grids.

[0022] According to the "Earth Space Grid Coding Rules" (GB / T 40087-2001) (hereinafter referred to as the "Coding Rules"), an upper-level grid is divided into four lower-level grids according to longitude and latitude. In an embodiment of the present invention, the area is gridded according to the set earth space grid level. Selecting a grid with a higher level can obtain more accurate calculation results, but the storage space and calculation speed will also deteriorate rapidly. The grid of the last layer of division is called the bottom grid. The predicted basic altitude data is a mapping pair of longitude and latitude and the basic altitude, which is stored in the bottom grid after division. In order to optimize the storage space and increase the calculation speed, one bottom grid is used to store multiple mapping pairs.

[0023] According to the Coding Rules, since each upper-level geospatial grid can be divided into four lower-level geospatial grids, it is preferred to use a quadtree to store geospatial grids, and the bottom-level grid stores mapping pairs including basic altitudes.

[0024] S2. Obtain the flight parameters of low-altitude aircraft through low-altitude detection devices.

[0025] There are many flight parameters for low-altitude aircraft, which can be divided into basic flight parameters and extended flight parameters. Basic flight parameters include identification code, low-altitude aircraft position latitude, low-altitude aircraft position longitude, and low-altitude aircraft altitude. Extended flight parameters include: low-altitude aircraft type, take-off status, heading angle, low-altitude aircraft horizontal speed, low-altitude aircraft vertical speed, low-altitude aircraft pressure altitude, operator position latitude, operator position longitude, etc. Basic flight parameters are very important for subsequent calculations. Extended flight parameters can be used for further precise calculations and analysis.

[0026] This step can obtain the flight parameters of low-altitude aircraft using interactive or non-interactive methods, including: 1) Use interactive methods to establish communication connections with low-altitude aircraft and obtain the flight parameters of low-altitude aircraft.

[0027] Low-altitude detection devices can use the communication protocols and standards disclosed by low-altitude aircraft, such as the Remote ID protocol. These protocols and standards ensure that both parties can correctly send and receive information and achieve effective communication. After selecting the appropriate communication band, frequency and technology, the communication link can be established between the low-altitude detection device and the low-altitude aircraft. After the communication link is successfully established, both parties can start transmitting data. This data can include location identification code, location information and status information.

[0028] According to the "Several Provisions on the Management of the Production of Civil Unmanned Aerial Vehicles", each low-altitude aircraft is equipped with a unique identification code. The management department can use the identification code to more effectively supervise low-altitude aircraft and prevent illegal operations such as illegal flying and disrupting flights. The identification code usually contains the manufacturer's name code, product model code and serial number (SN). The combination of these codes ensures that each low-altitude aircraft has a unique identity. The manufacturer needs to report the unique product identification code information to the management department before the product is put on the market or before the first flight to ensure the accuracy and traceability of the information.

[0029] It should be noted that for low-altitude aircraft that do not support or close public communication protocols and standards, the low-altitude detection device cannot establish a communication connection with them, nor can it use interactive methods to obtain the low-altitude aircraft's identification code, flight altitude, flight longitude and latitude and other information.

[0030] 2) Use non-interactive methods to obtain the flight altitude, latitude and longitude of low-altitude aircraft.

[0031] Use non-interactive methods to obtain the flight altitude, latitude and longitude of low-altitude aircraft, without establishing a communication connection with the low-altitude aircraft, to obtain the flight altitude, latitude and longitude of low-altitude aircraft. The methods that can be used include: 1) Radar measurement method. Use radar to send radar waves to low-altitude aircraft and receive the reflected signals. By calculating the time difference or phase difference of the round trip of the radar waves, the aircraft's flight altitude and flight longitude and latitude can be calculated.

[0032] 2) Multi-point positioning method. Multiple low-altitude detection devices can be set up on the ground to determine the aircraft's flight altitude and longitude and latitude by measuring the signal propagation time difference or phase difference between the low-altitude detection device and the aircraft.

[0033] S3. Calculate the real-time basic altitude of low-altitude aircraft based on the real-time latitude and longitude of the UAV.

[0034] The specific steps are as follows: 1) Based on the longitude and latitude of the low-altitude aircraft, the quadtree query method is used to recursively search the nodes of the quadtree to find the bottom-level blocks; 2) Use the Euclidean distance formula to calculate the distance between the longitude and latitude of the low-altitude aircraft and each longitude and latitude data in the bottom block to find the point with the shortest distance; 3) The real-time basic altitude of low-altitude aircraft is obtained through the mapping of longitude and latitude to basic altitude.

[0035] S4. Determine whether the flight of a low-altitude aircraft is normal or abnormal based on the flight supervision requirements for low-altitude aircraft.

[0036] Low-altitude aircraft flight anomalies can be divided into multiple categories, including unregistered identification code, flight in a controlled area, unreported flight at excessive altitude, abnormal flight reporting time, abnormal flight reporting altitude, etc. This step includes the following sub-steps: S41. Determine whether the flight is abnormal based on the low-altitude aircraft identification code.

[0037] If the low-altitude aircraft identification code can be obtained in step S2, the calculation logic is as follows: Figure 2 As shown, according to the Interim Regulations on Unmanned Aircraft Flight Management, the low-altitude aircraft identification code must complete real-name registration. If the real-name registration is not completed, it will be judged as a flight abnormality and the reason value will be "Identification code not registered".

[0038] S42. Determine whether the low-altitude aircraft belongs to the controlled area based on its latitude and longitude.

[0039] Determine whether the real-time latitude and longitude of the low-altitude aircraft belongs to the controlled area. If it is in the controlled area, it is judged as a flight abnormality and the reason value is "flight in controlled area".

[0040] The following method can be used to determine whether it belongs to the control area by judging the longitude and latitude: 1) Compare the real-time longitude and latitude of the low-altitude aircraft with the longitude and latitude of the control area to determine whether it belongs to the control area.

[0041] 2) Alternatively, follow the steps in step S1 to establish the geospatial grid code of the control area. According to the "Coding Rules", convert the longitude and latitude into the geospatial grid code to determine whether it belongs to the geospatial grid code of the control area.

[0042] S43. Calculate the true flight altitude based on the real-time basic altitude of the low-altitude aircraft.

[0043] The true flight height is the flight altitude minus the base altitude corresponding to the latitude and longitude of this place. Determine whether the true flight height of the low-altitude aircraft is greater than the true height limit. If it is less than or equal to the true height limit, it is judged that the flight is normal. If it is greater than the true height limit, further flight verification is performed. According to the "Interim Regulations on the Flight Management of Unmanned Aerial Vehicles", the true height limit is 120 meters.

[0044] S44. When the true flight altitude exceeds the true altitude limit, a flight check is performed.

[0045] The flight reporting of low-altitude aircraft refers to the process of reporting and approving the flight plan to the relevant departments in accordance with relevant regulations and requirements before an organization or individual uses a low-altitude aircraft for flight activities. Through flight reporting, relevant departments can understand the flight plan and ensure that the flight activities are carried out within the specified airspace and time to avoid conflicts with other aircraft. Relevant departments can also monitor and control the flight activities throughout the process to ensure that the flight activities comply with the requirements of laws and regulations.

[0046] When applying for a flight, you need to fill out a flight plan application form, including the identification code, flight time, location, altitude, route and other information. The approval department will make a comprehensive consideration of factors such as the content of the flight plan and the use of airspace to decide whether to approve the flight. If the flight plan is approved, the unit or individual needs to carry out the flight activities in accordance with the approved content.

[0047] The flight verification is performed according to the following steps: 1) For low-altitude aircraft with known identification codes, check whether the flight has been reported. For low-altitude aircraft with unknown identification codes, check whether there is any flight reported in this area.

[0048] 2) If there is no flight report, it is judged as flight abnormality, and the reason value is "over-altitude flight not reported". If there is a flight report, check whether the current flight time is within the flight report time range. If not, it is judged as flight abnormality, and the reason value is "flight report time abnormality". If the flight report time is normal, check whether the flight latitude and longitude and flight true altitude are within the flight report space range. If they are beyond the range, it is judged as flight abnormality, and the reason value is "flight report altitude abnormality".

[0049] It should be noted that when conducting flight verification on low-altitude aircraft with unknown identification codes, since it is impossible to uniquely identify the low-altitude aircraft through the identification code and certain coincidences cannot be completely ruled out, misjudgments may occur in the flight verification, but the probability of such misjudgments is relatively low.

[0050] S5. Execute the supervision procedure according to the result of the normal or abnormal flight judgment. This step includes the following sub-steps: S51, record the flight data of the low-altitude aircraft and store it in a database. The flight data includes identification code, flight altitude, flight longitude and latitude, etc. These stored flight data can be used for filing, evidence collection or other further analysis.

[0051] S52: In case of flight anomalies, a warning is issued to the operator of the low-altitude aircraft to inform him of the flight anomaly. According to the type of anomaly, corresponding emergency measures are taken. For example, if the low-altitude aircraft deviates from the prescribed route, it can be guided back to the correct route; if the altitude exceeds the limit, it is required to lower the altitude.

[0052] S53. If the abnormal behavior of a low-altitude aircraft constitutes a serious safety hazard, it may be immediately restricted or prohibited from continuing to fly. The abnormal flight incident will be investigated later, and the operator of the low-altitude aircraft and / or the relevant responsible parties will be punished or other measures will be taken based on the investigation results.

[0053] Through the above steps, the embodiment of the present invention can realize a real-time analysis method for low-altitude aircraft detection based on three-dimensional spatial data, and effectively manage low-altitude aircraft flying in the area.

[0054] The above embodiments are only used to help understand the method and core idea of ​​the present invention. It should be noted that, for those skilled in the art, several improvements and modifications can be made to the present invention without departing from the principles of the present invention, and these improvements and modifications also fall within the scope of protection of the claims of the present invention.

Claims

1. A real-time analysis method for low-altitude aircraft detection based on three-dimensional spatial data, characterized in that: The following steps are involved: S1. Set the geospatial grid level, divide the area into grids, and store the predicted basic altitude data in the divided bottom grids; S2. Use low-altitude detection equipment to obtain flight parameters of low-altitude aircraft; S3. Calculate the real-time basic altitude of low-altitude aircraft based on the real-time latitude and longitude of the UAV; S4. Determine whether the flight of a low-altitude aircraft is normal or abnormal according to the flight supervision requirements of low-altitude aircraft; S5. Execute low-altitude aircraft supervision procedures based on the judgment results of normal or abnormal flight.

2. The method for real-time analysis of low-altitude aircraft detection based on three-dimensional spatial data according to claim 1, characterized in that: The step S1 also includes: using a quadtree to store the earth space grid.

3. The real-time analysis method for low-altitude aircraft detection based on three-dimensional spatial data according to claim 1 is characterized in that: The step S2 comprises: 1) Use interactive methods to establish communication connections with low-altitude aircraft and obtain flight parameters of low-altitude aircraft; 2) Use non-interactive methods to obtain the flight parameters of low-altitude aircraft; The flight parameters include basic flight parameters and extended flight parameters; the basic flight parameters include low-altitude aircraft identification code, low-altitude aircraft position latitude, low-altitude aircraft position longitude, and low-altitude aircraft altitude; the extended flight parameters include: low-altitude aircraft type, take-off status, heading angle, low-altitude aircraft horizontal speed, low-altitude aircraft vertical speed, low-altitude aircraft pressure altitude, operator position latitude, and operator position longitude.

4. The method for real-time analysis of low-altitude aircraft detection based on three-dimensional spatial data according to claim 3 is characterized in that: The interaction method is implemented through a remote identification protocol.

5. The method for real-time analysis of low-altitude aircraft detection based on three-dimensional spatial data according to claim 1, characterized in that: The step S3 comprises: 1) Based on the longitude and latitude of the low-altitude aircraft, the quadtree query method is used to recursively search the nodes of the quadtree to find the bottom-level blocks; 2) Use the Euclidean distance formula to calculate the distance between the longitude and latitude of the low-altitude aircraft and each longitude and latitude data in the bottom block to find the point with the shortest distance; 3) The real-time basic altitude of low-altitude aircraft is obtained through the mapping of longitude and latitude to basic altitude.

6. The method for real-time analysis of low-altitude aircraft detection based on three-dimensional spatial data according to claim 3 is characterized in that: The non-interactive method includes: 1) Radar measurement method: Use radar to transmit radar waves to low-altitude aircraft and receive the reflected signals. By calculating the time difference or phase difference of the round-trip radar waves, the aircraft's flight altitude and flight longitude and latitude can be calculated; 2) Multi-point positioning method: multiple low-altitude detection devices are set up on the ground, and the aircraft's flight altitude and flight longitude and latitude are determined by measuring the signal propagation time difference or phase difference between the low-altitude detection device and the aircraft.

7. The method for real-time analysis of low-altitude aircraft detection based on three-dimensional spatial data according to claim 1, characterized in that: The step S4 comprises: S41. Determine whether the flight is abnormal based on the low-altitude aircraft identification code; S42. Determine whether the low-altitude aircraft belongs to the control area based on its flight latitude and longitude; S43. Calculate the true flight altitude based on the flight latitude and longitude and the flight altitude of the low-altitude aircraft; S44. When the true flight altitude exceeds the true altitude limit, a flight check is performed.

8. The method for real-time analysis of low-altitude aircraft detection based on three-dimensional spatial data according to claim 7, characterized in that: The flight anomalies include unregistered identification code, flight in a controlled area, failure to report over-altitude flight, abnormal flight reporting time, and abnormal flight reporting altitude; The flight verification includes: 1) For low-altitude aircraft with known identification codes, check whether the flight has been reported; for low-altitude aircraft with unknown identification codes, check whether there is a flight report in the area; 2) If there is no flight report, it is judged as flight abnormality, and the reason value is "over-altitude flight not reported"; if there is a flight report, check whether the current flight time is within the flight report time range. If not, it is judged as flight abnormality, and the reason value is "flight report time abnormality"; if the flight report time is normal, check whether the flight latitude and longitude and flight true altitude are within the flight report space range. If they are beyond the range, it is judged as flight abnormality, and the reason value is "flight report altitude abnormality".

9. A method for real-time analysis of low-altitude aircraft detection based on three-dimensional spatial data according to any one of claims 1 to 8, characterized in that: The step S5 comprises: S51, recording the flight data of the low-altitude aircraft and storing it in a database; S52. In case of abnormal flight, issue a warning to the operator of low-altitude aircraft to inform him of the abnormal flight; S53. If the abnormal behavior of a low-altitude aircraft poses a serious safety hazard, it shall be immediately restricted or prohibited from continuing to fly.

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