Overload area detection system and detection method applied to low-altitude airspace

Abstract

The system comprises a public information service provider CISP, an unmanned aerial vehicle air traffic management service provider UTMSP, a ground control station GCS and an unmanned aerial vehicle. According to the invention, the occupation condition of the airspace unit can be quickly updated along with the updating of the flight path of the unmanned aerial vehicle in the airspace unit, and the overload area detection system applied to the low-altitude airspace serves as a part of the unmanned aerial vehicle non-overload area flight path planning system and is responsible for overload area detection; according to the method, rapid overload area detection of the low-altitude airspace unmanned aerial vehicle in consideration of flight time uncertainty is realized, a currently used rasterized low-altitude airspace model can be effectively compatible, and the calculation time of the rasterized low-altitude airspace model is not remarkably increased along with the increase of the traffic density of the unmanned aerial vehicle in the low-altitude airspace; and the calculation amount of overload area discrimination calculation is simplified based on the non-overload area discrimination condition of the airspace unit.

Description

Technical Field

[0001] The present invention relates to the technical field of air traffic management, and in particular to an overload area detection system and a detection method applied to low-altitude airspace. Background Art

[0002] The UAV flight conflict detection system for low-altitude airspace obtains the planned flight tracks of all relevant UAVs in the airspace through the Common Information Service Provider (CISP), and identifies the overloaded areas in the low-altitude airspace by calculating the temporal and spatial position distribution relationship between them, providing a decision-making basis for UAVs to adjust their tracks to avoid entering overloaded areas or generate tracks in non-overloaded areas, thereby improving the safety and efficiency of UAV operations in low-altitude airspace. If the flight mission demand in a time window of an airspace unit exceeds its capacity, the time window of the airspace unit is called an overloaded area. The expression is:

[0003] d u,k ≤C u,k ,u∈U,k∈K

[0004] Among them, U and K are the sets of spatial units and time windows respectively, d u,k and C u,k They represent the flight mission requirements and capacity of airspace unit u in time window k. As long as the time when UAV i enters airspace unit u is within the time interval If , UAV i is recorded as a flight mission requirement of airspace unit u in time window k. Where ΔT is the width of the time window, is the flight time of UAV i in airspace unit u. The non-overload area track means that the UAV’s track does not pass through the overload area.

[0005] Compared with traditional commercial transport aircraft (such as Boeing 737), drones operating at low altitudes are generally smaller in mass and size, and their flights are more easily affected by the environment, thus having greater flight uncertainty. However, the current overload area detection methods used in low-altitude airspace usually do not take uncertainty into account, which limits the practical application potential of flight mission demand and capacity balancing operations based on them, that is, the use of deterministic flight mission demand calculations will result in poor ability to characterize actual conditions and easily lead to waste of airspace resources.

[0006] In addition, when considering flight uncertainty, calculating the occupancy of airspace units is a complex combined probability calculation model. In large-scale scenarios, it is very time-consuming to update the occupancy of each relevant airspace unit in the airspace for each new drone track, which greatly limits the calculation speed of the pre-takeoff no-overload area track planning based on this. This makes it more challenging to generate no-overload area tracks for drones performing temporary tasks (takeout, rescue, etc., which need to quickly obtain tracks and perform flight missions after receiving flight missions). Summary of the invention

[0007] In view of the above problems, the present invention provides an overload area detection system and detection method applied to low-altitude airspace, which can quickly update the occupancy status of the airspace unit as the drone track in the airspace unit is updated. The overload area detection system applied to low-altitude airspace is a part of the drone no-overload area track planning system, and is responsible for overload area detection.

[0008] One object of the present invention is to provide an overload area detection system applied to low-altitude airspace. The overload area detection system applied to low-altitude airspace is a part of a UAV non-overload area trajectory planning system and is responsible for overload area detection.

[0009] The overload area detection system applied to low-altitude airspace includes: a public information service provider CISP, an unmanned aerial vehicle air traffic management service provider UTMSP, a ground control station GCS and unmanned aerial vehicles.

[0010] The ground control station GCS sends a trajectory planning request to the UAV air traffic management service provider UTMSP according to its flight mission requirements; the public information service provider CISP sends the current occupancy status of the airspace unit to UTMSP so that it can plan a hotspot-free trajectory.

[0011] The UAV air traffic management service provider UTMSP is used to contact the ground control station to verify the role of the UTMSP, such as flight missions, aircraft performance and planned trajectory, user provision of flight-related services, and detection services for non-overloaded area track planning of pre-flight planned trajectory;

[0012] The ground control station GCS controls the UVA flight according to the service information provided by the UAV air traffic management service provider UTMSP.

[0013] Furthermore, the no-overload area trajectory planning is performed by the UAV air traffic management service provider UTMSP, which obtains the planned trajectory information of all UAVs in the low-speed airspace from CISP and performs no-overload area trajectory planning for the UAVs controlled by the ground control station GCS it serves.

[0014] Another object of the present invention is to provide a detection method for an overload area detection system applied to low-altitude airspace, comprising:

[0015] Step 1: rasterize the low-altitude airspace of the UAV flight track to obtain multiple airspace units;

[0016] Preferably, the low-altitude airspace is from the ground to an altitude of 1000 meters;

[0017] Step 2: Establish the time relationship between the drone entering and exiting the airspace unit;

[0018] Let h = 1. When h = 1, it is the first airspace unit; i and j both represent drones;

[0019] Based on the time relationship between drones entering and exiting airspace units, the probability of drone i entering the hth airspace unit at time k is obtained;

[0020] Preferably, the time relationship between the drone entering and exiting the airspace unit is expressed as:

[0021]

[0022] in, represents the time when UAV i enters the hth airspace unit. Let the coordinates of the hth airspace unit be (m, n), where m is the horizontal coordinate index of the airspace unit and n is the vertical coordinate index of the airspace unit; represents the time when UAV i exits the hth airspace unit, represents the flight time of UAV i in the hth airspace unit.

[0023] Furthermore, the probability of the UAV i entering the hth airspace unit at time k is expressed as:

[0024]

[0025] in, is the probability that UAV i enters the hth airspace unit at time k; ΔT is the time window length; f(t,h,i) is the time probability that UAV i enters the hth airspace unit, N(·) represents the distribution function, represents the time when UAV i plans to enter the hth airspace unit, as the mean of the distribution function, represents the flight time before UAV i enters the hth airspace unit, σ 2 (·) represents the variance function.

[0026] Step 3: Obtain the probability that the qth flight mission requirement of UAV i at time k is to enter the hth airspace unit, and obtain the probability that the hth airspace unit is not overloaded at time k based on the probability that the qth flight mission requirement of UAV i at time k is to enter the hth airspace unit;

[0027] Preferably, the probability expression that the h-th airspace unit is not overloaded at the time k is:

[0028]

[0029] in, is the probability that the number of drones entering the h-th airspace unit at time k is less than or equal to the number of drones that the airspace unit can accommodate, that is, the probability that the h-th airspace unit is not overloaded at time k, is the number of drones that can be accommodated by the h-th airspace unit at time k, is the flight mission requirement of drone i at time k, q is the probability of entering the hth airspace unit, and the flight mission requirement is whether to enter the airspace unit;

[0030] Preferably, the expression for the probability that the qth flight mission requirement of the drone i at time k is to enter the airspace unit is:

[0031]

[0032] in, is the probability that the qth flight mission requirement of UAV i at time k is to enter the airspace unit, is the number of drones that can be accommodated by the h-th airspace unit at time k, is the number of combinations, indicating that the qth flight mission requirement is selected from the number of drones that can be accommodated by the hth airspace unit at time k, and the rest of the events do not occur, λ i is the occurrence index of drone i, which takes 1 when drone i occurs, otherwise it takes 0.

[0033] Step 4, define the overload tolerance ζ∈[0,1) of the airspace unit; the overload tolerance of the airspace unit ensures that the probability of overload of the airspace unit at time k is less than or equal to the overload tolerance;

[0034] The constraint condition that the hth airspace unit is not overloaded is set based on the probability that the hth airspace unit is not overloaded at time k and the overload tolerance of the airspace unit;

[0035] Preferably, the h-th airspace unit has no overload constraint, and the expression is:

[0036]

[0037] Step 5: Obtain the probability that UAV j enters the hth airspace unit at time k;

[0038] Based on the probability of UAV j entering the hth airspace unit at time k, the probability of the hth airspace unit not being overloaded at time k is updated to obtain the updated probability of the hth airspace unit not being overloaded at time k;

[0039] Step 6: Based on the updated non-overload probability of the h-th airspace unit at the time k, the probability of no overload area in the h-th airspace unit at the time k is obtained;

[0040] Preferably, the updated non-overload probability of the h-th airspace unit at the time k is expressed as:

[0041]

[0042] when Right now When

[0043]

[0044] in, is the updated non-overload probability of the h-th spatial unit at time k, is the probability that UAV j enters the hth airspace unit at time k.

[0045] Step 7: Based on the constraint condition that the hth airspace unit has no overload and the probability that the hth airspace unit has no overload area at time k;

[0046] Obtain the constraints for UAV j to enter the hth airspace unit at time k;

[0047] The constraint condition that UAV j enters the h-th airspace unit at time k is used to obtain the remaining maximum occupancy probability of UAV j for the h-th airspace unit at time k;

[0048] Preferably, the remaining maximum occupancy probability expression of the drone j at time k for the hth airspace unit is:

[0049]

[0050] in, is the remaining maximum occupancy probability of UAV j at time k for the hth airspace unit.

[0051] Step 8: Based on the probability of UAV j entering the hth airspace unit at time k and the remaining maximum occupancy probability of UAV j for the hth airspace unit at time k, establish the judgment condition of the hth airspace unit without overload area;

[0052] Using the h-th airspace unit no-overload area judgment condition, the h-th airspace unit of the UAV track is judged to obtain the judgment results of the h airspace units and record them; the judgment result is whether the h-th airspace unit is a no-overload area;

[0053] Step 9, determine whether h is greater than or equal to H, where H is the number of airspace units of the UAV track. If not, set h=h+1 and return to step 2; if so, obtain the judgment results of multiple airspace units. If each airspace unit meets the corresponding airspace unit no-overload area judgment condition, it means that the UAV track is a no-overload area track. If not, it means that the UAV track is an overload area track.

[0054] Compared with the prior art, the present invention has at least the following beneficial effects:

[0055] The present invention realizes the rapid overload area detection of UAVs in low-altitude airspace taking into account the uncertainty of flight time, can effectively be compatible with the currently used rasterized low-altitude airspace model, and makes its calculation time not significantly increase with the increase of UAV traffic density in low-altitude airspace; based on the non-overload area judgment condition of airspace unit, the calculation amount of overload area judgment calculation is simplified. BRIEF DESCRIPTION OF THE DRAWINGS

[0056] The drawings are only for the purpose of illustrating particular embodiments and are not to be construed as limiting the invention.

[0057] Figure 1 It is a schematic diagram of the structure and flow chart of the UAV no-overload area trajectory planning system in an embodiment of the present invention. DETAILED DESCRIPTION

[0058] In order to more clearly understand the above-mentioned purpose, features and advantages of the present invention, the present invention is further described in detail below in conjunction with the accompanying drawings and specific embodiments. It should be noted that, in the absence of conflict, the embodiments of the present invention and the features in the embodiments can be combined with each other. In addition, the present invention can also be implemented in other ways different from those described herein, and therefore, the protection scope of the present invention is not limited by the specific embodiments disclosed below.

[0059] A specific embodiment of the present invention, as Figure 1 , discloses an overload area detection system and detection method for low-altitude airspace.

[0060] In order to illustrate the effectiveness of the method proposed in the present invention, the above technical solution of the present invention is described in detail below through a specific embodiment, and the specific implementation steps are as follows:

[0061] One object of the present invention is to provide an overload area detection system applied to low-altitude airspace. The overload area detection system applied to low-altitude airspace is a part of a UAV non-overload area trajectory planning system and is responsible for overload area detection.

[0062] The overload area detection system applied to low-altitude airspace includes: a public information service provider CISP, an unmanned aerial vehicle air traffic management service provider UTMSP, a ground control station GCS and unmanned aerial vehicles.

[0063] The ground control station GCS sends a trajectory planning request to the UAV air traffic management service provider UTMSP according to its flight mission requirements; the public information service provider CISP sends the current occupancy status of the airspace unit to UTMSP so that it can plan a hotspot-free trajectory.

[0064] The UAV air traffic management service provider UTMSP is used to contact the ground control station to verify the role of the UTMSP, such as flight missions, aircraft performance and planned trajectory, user provision of flight-related services, and detection services for non-overloaded area track planning of pre-flight planned trajectory;

[0065] The ground control station GCS controls the UVA flight according to the service information provided by the UAV air traffic management service provider UTMSP.

[0066] Furthermore, the no-overload area trajectory planning is performed by the UAV air traffic management service provider UTMSP, which obtains the planned trajectory information of all UAVs in the low-speed airspace from CISP and performs no-overload area trajectory planning for the UAVs controlled by the ground control station GCS it serves.

[0067] Another object of the present invention is to provide a detection method for an overload area detection system applied to low-altitude airspace, comprising:

[0068] Step 1: rasterize the low-altitude airspace of the UAV flight track to obtain multiple airspace units;

[0069] Preferably, the low-altitude airspace is from the ground to an altitude of 1000 meters;

[0070] Step 2: Establish the time relationship between the drone entering and exiting the airspace unit;

[0071] Let h = 1. When h = 1, it is the first airspace unit; i and j both represent drones;

[0072] Based on the time relationship between drones entering and exiting airspace units, the probability of drone i entering the hth airspace unit at time k is obtained;

[0073] Preferably, the time relationship between the drone entering and exiting the airspace unit is expressed as:

[0074]

[0075] in, represents the time when UAV i enters the hth airspace unit. Let the coordinates of the hth airspace unit be (m, n), where m is the horizontal coordinate index of the airspace unit and n is the vertical coordinate index of the airspace unit; represents the time when UAV i exits the hth airspace unit, represents the flight time of UAV i in the hth airspace unit.

[0076] Furthermore, the probability of the UAV i entering the hth airspace unit at time k is expressed as:

[0077]

[0078] in, is the probability that UAV i enters the hth airspace unit at time k; ΔT is the time window length; f(t,h,i) is the time probability that UAV i enters the hth airspace unit, N(·) represents the distribution function, represents the time when UAV i plans to enter the hth airspace unit, as the mean of the distribution function, represents the flight time before UAV i enters the hth airspace unit, σ 2 (·) represents the variance function.

[0079] Step 3: Obtain the probability that the qth flight mission requirement of UAV i at time k is to enter the hth airspace unit, and obtain the probability that the hth airspace unit is not overloaded at time k based on the probability that the qth flight mission requirement of UAV i at time k is to enter the hth airspace unit;

[0080] Preferably, the probability expression that the h-th airspace unit is not overloaded at the time k is:

[0081]

[0082] in, is the probability that the number of drones entering the h-th airspace unit at time k is less than or equal to the number of drones that the airspace unit can accommodate, that is, the probability that the h-th airspace unit is not overloaded at time k, is the number of drones that can be accommodated by the h-th airspace unit at time k, is the flight mission requirement of drone i at time k, q is the probability of entering the hth airspace unit, and the flight mission requirement is whether to enter the airspace unit;

[0083] Preferably, the expression for the probability that the qth flight mission requirement of the drone i at time k is to enter the airspace unit is:

[0084]

[0085] in, is the probability that the qth flight mission requirement of UAV i at time k is to enter the airspace unit, is the number of drones that can be accommodated by the h-th airspace unit at time k, is the number of combinations, indicating that the qth flight mission requirement is selected from the number of drones that can be accommodated by the hth airspace unit at time k, and the rest of the events do not occur, λ i is the occurrence index of drone i, which takes 1 when drone i occurs, otherwise it takes 0.

[0086] Step 4, define the overload tolerance ζ∈[0,1) of the airspace unit; the overload tolerance of the airspace unit ensures that the probability of overload of the airspace unit at time k is less than or equal to the overload tolerance;

[0087] The constraint condition that the hth airspace unit is not overloaded is set based on the probability that the hth airspace unit is not overloaded at time k and the overload tolerance of the airspace unit;

[0088] Preferably, the h-th airspace unit has no overload constraint, and the expression is:

[0089]

[0090] Step 5: Obtain the probability that UAV j enters the hth airspace unit at time k;

[0091] Based on the probability of UAV j entering the hth airspace unit at time k, the probability of the hth airspace unit not being overloaded at time k is updated to obtain the updated probability of the hth airspace unit not being overloaded at time k;

[0092] Step 6: Based on the updated non-overload probability of the h-th airspace unit at the time k, the probability of no overload area in the h-th airspace unit at the time k is obtained;

[0093] Preferably, the updated non-overload probability of the h-th airspace unit at the time k is expressed as:

[0094]

[0095] when Right now When

[0096]

[0097] in, is the updated non-overload probability of the h-th spatial unit at time k, is the probability that UAV j enters the hth airspace unit at time k.

[0098] Step 7: Based on the constraint condition that the hth airspace unit has no overload and the probability that the hth airspace unit has no overload area at time k;

[0099] Obtain the constraints for UAV j to enter the hth airspace unit at time k;

[0100] The constraint condition that UAV j enters the h-th airspace unit at time k is used to obtain the remaining maximum occupancy probability of UAV j for the h-th airspace unit at time k;

[0101] Preferably, the remaining maximum occupancy probability expression of the drone j at time k for the hth airspace unit is:

[0102]

[0103] in, is the remaining maximum occupancy probability of UAV j at time k for the hth airspace unit.

[0104] Step 8: Based on the probability of UAV j entering the hth airspace unit at time k and the remaining maximum occupancy probability of UAV j for the hth airspace unit at time k, establish the judgment condition of the hth airspace unit without overload area;

[0105] Using the h-th airspace unit no-overload area judgment condition, the h-th airspace unit of the UAV track is judged to obtain the judgment results of the h airspace units and record them; the judgment result is whether the h-th airspace unit is a no-overload area;

[0106] Step 9, determine whether h is greater than or equal to H, where H is the number of airspace units of the UAV track. If not, set h=h+1 and return to step 2; if so, obtain the judgment results of multiple airspace units. If each airspace unit meets the corresponding airspace unit no-overload area judgment condition, it means that the UAV track is a no-overload area track. If not, it means that the UAV track is an overload area track.

[0107] The above description is only a preferred specific implementation manner of the present invention, but the protection scope of the present invention is not limited thereto. Any changes or substitutions that can be easily conceived by any technician familiar with the technical field within the technical scope disclosed by the present invention should be covered within the protection scope of the present invention.

Claims

1. A detection method for an overload area detection system applied to low-altitude airspace, characterized in that: Step 1: rasterize the low-altitude airspace of the UAV flight track to obtain multiple airspace units; Step 2: Establish the time relationship between the drone entering and exiting the airspace unit; Let h = 1. When h = 1, it is the first spatial unit; Based on the time relationship between drones entering and exiting airspace units, the probability of drone i entering the hth airspace unit at time k is obtained; Step 3: Obtain the probability that the qth flight mission requirement of UAV i at time k is to enter the hth airspace unit, and obtain the probability that the hth airspace unit is not overloaded at time k based on the probability that the qth flight mission requirement of UAV i at time k is to enter the hth airspace unit; Step 4, define the overload tolerance of the airspace unit; set the constraint condition that the hth airspace unit is not overloaded based on the probability that the hth airspace unit is not overloaded at time k and the overload tolerance of the airspace unit; Step 5: Obtain the probability that UAV j enters the hth airspace unit at time k; Based on the probability of UAV j entering the hth airspace unit at time k, the probability of the hth airspace unit not being overloaded at time k is updated to obtain the updated probability of the hth airspace unit not being overloaded at time k; Step 6: Based on the updated non-overload probability of the h-th airspace unit at the time k, the probability of no overload area in the h-th airspace unit at the time k is obtained; Step 7: Based on the constraint condition that the hth airspace unit is not overloaded and the probability of the hth airspace unit not having an overloaded area at time k, obtain the remaining maximum occupancy probability of the hth airspace unit by UAV j at time k; Step 8: Based on the probability of UAV j entering the hth airspace unit at time k and the remaining maximum occupancy probability of UAV j for the hth airspace unit at time k, establish the judgment condition of the hth airspace unit without overload area; Using the h-th airspace unit no-overload area judgment condition to judge the h-th airspace unit of the UAV track, obtain the judgment results of h airspace units, and record them; Step 9, determine whether h is greater than or equal to H, where H is the number of airspace units of the drone track. If not, set h=h+1 and return to step 2; if so, obtain the judgment results of multiple airspace units, and judge whether the drone track is an overload area track based on the judgment results.

2. The detection method of the overload area detection system applied to low-altitude airspace according to claim 1 is characterized in that: The time relationship between the drone entering and exiting the airspace unit is expressed as: in, represents the time when UAV i enters the hth airspace unit; represents the time when UAV i exits the hth airspace unit, represents the flight time of UAV i in the hth airspace unit.

3. The detection method of the overload area detection system applied to low-altitude airspace according to claim 2 is characterized in that: The probability that the UAV i enters the hth airspace unit at time k is expressed as: in, is the probability that UAV i enters the hth airspace unit at time k; ΔT is the time window length; f(t,h,i) is the time probability that UAV i enters the hth airspace unit, N(·) represents the distribution function, represents the time when UAV i plans to enter the hth airspace unit, as the mean of the distribution function, represents the flight time before UAV i enters the hth airspace unit, σ 2 (·) represents the variance function.

4. The detection method of the overload area detection system applied to low-altitude airspace according to claim 3 is characterized in that: The probability expression that the h-th airspace unit is not overloaded at the time k is: in, is the probability that the number of drones entering the hth airspace unit at time k is less than or equal to the number of drones that the airspace unit can accommodate, is the number of drones that can be accommodated by the h-th airspace unit at time k, is the probability that the qth flight mission requirement of UAV i at time k is to enter the hth airspace unit, where the flight mission requirement is whether to enter the airspace unit.

5. The detection method of the overload area detection system applied to low-altitude airspace according to claim 4 is characterized in that: The expression for the probability that the qth flight mission requirement of the UAV i at time k is to enter the airspace unit is: in, is the probability that the qth flight mission requirement of UAV i at time k is to enter the airspace unit, is the number of drones that can be accommodated by the h-th airspace unit at time k, represents the requirement to select the qth flight mission from the number of drones that can be accommodated by the hth airspace unit at time k, λ i Indicators for drone i.

6. The detection method of the overload area detection system applied to low-altitude airspace according to claim 5 is characterized in that: The expression of the remaining maximum occupancy probability of the drone j at time k for the hth airspace unit is: in, is the remaining maximum occupancy probability of UAV j at time k for the hth airspace unit.

7. The detection method of the overload area detection system applied to low-altitude airspace according to claim 1 is characterized in that: Step 7: Based on the h-th no-overload area constraint and the probability of no-overload area in the h-th airspace unit at time k; Obtain the constraints for UAV j to enter the hth airspace unit at time k; The constraint condition that UAV j enters the h-th airspace unit at time k is used to obtain the remaining maximum occupancy probability of UAV j for the h-th airspace unit at time k.

8. The detection method of the overload area detection system applied to low-altitude airspace according to claim 1 is characterized in that: The specific steps of determining whether the drone track is an overload area track according to the determination result in step 9 include: The judgment results of multiple airspace units are obtained. If each airspace unit meets the corresponding airspace unit non-overload area judgment condition, it means that the UAV track is a non-overload area track. If not, it means that the UAV track is an overload area track.

9. The detection method of the overload area detection system applied to low-altitude airspace according to claim 1 is characterized in that: The overload tolerance of the airspace unit ensures that the probability of overload of the airspace unit at time k is less than or equal to the overload tolerance.

10. An overload area detection system applied to low-altitude airspace, using the detection method described in any one of claims 1 to 9, characterized in that: It includes a public information service provider CISP, an unmanned aerial vehicle air traffic management service provider UTMSP, a ground control station GCS and unmanned aerial vehicles; the overload area detection system applied to low-altitude airspace is used for overload area detection.

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