Dynamic safety interval setting method and device for low-altitude vertical take-off and landing aircraft, medium and product

Abstract

The invention discloses a dynamic safety interval setting method and device for a low-altitude vertical take-off and landing aircraft, a medium and a product, and relates to the technical field of aircraft safety. The method comprises the steps that an inner layer of a protection area is determined according to the fuselage size and the safety redundancy coefficient of the aircraft; determining the outer layer of the protection area according to the maximum positioning error in the x-axis or y-axis direction caused by airborne communication, navigation and monitoring systems of the aircraft; a safety area of each aircraft is obtained; the standard deviation of the first performance standard deviation of the two aircrafts in the longitudinal direction, the lateral direction and the vertical direction is calculated according to the first performance standard deviation, the minimum interval of the two aircrafts is calculated according to the standard deviation, finally, optimization is conducted through a particle swarm optimization algorithm, and in the preset area, the minimum interval is obtained on the premise that the minimum interval is met. And the number of aircrafts can be accommodated. According to different performances of the aircraft, the safety area around the aircraft changes in real time, and airspace resources are utilized to the maximum extent.

Description

TECHNICAL FIELD

[0001] The application relates to the technical field of aircraft safety, in particular to a low-altitude vertical take-off and landing aircraft dynamic safety interval setting method, device, medium and product. BACKGROUND

[0002] The low-altitude vertical take-off and landing aircraft refers to an aircraft capable of vertical take-off and landing in low-altitude airspace (usually below 1000 meters) without a long runway. The safety region of the existing low-altitude vertical take-off and landing aircraft is fixed and cannot be changed.

[0003] In order to overcome the limitations of the existing three-dimensional interval protection region technology, the field urgently needs a safety region that can be changed to maximize the use of airspace resources. The present study proposes a dynamic three-dimensional interval protection region design scheme. The scheme can adjust the size of the three-dimensional interval protection region in real time, ensure that the aircraft is always in a safe state during flight, and maximize the use of airspace resources, thereby meeting the future needs of civil aviation in aircraft safety supervision. SUMMARY

[0004] The purpose of the present application is to provide a low-altitude vertical take-off and landing aircraft dynamic safety interval setting method, device, medium and product, which can change the safety region around the aircraft in real time according to the different performance of the aircraft, and can maximize the use of airspace resources.

[0005] To achieve the above-mentioned purpose, the present application provides the following scheme:

[0006] In a first aspect, the present application provides a low-altitude vertical take-off and landing aircraft dynamic safety interval setting method, comprising:

[0007] According to the fuselage size and safety redundancy coefficient of the aircraft, the inner layer of the protection zone of each aircraft is determined;

[0008] According to the maximum positioning error in the x-axis or y-axis direction caused by the onboard communication, navigation and surveillance system of the aircraft, the outer layer of the protection zone of each aircraft is determined;

[0009] The inner layer of the protection zone and the outer layer of the protection zone are superimposed to obtain the safety region of each aircraft;

[0010] According to the first performance standard deviation of each aircraft, the standard deviation of the first performance standard deviation of two aircrafts in the longitudinal, lateral and vertical directions is calculated respectively; the first performance standard deviation is the standard deviation of the communication performance, navigation performance, monitoring performance and obstacle avoidance performance of the aircraft;

[0011] Based on the standard deviations of the first performance standard deviations of the two aircraft in the longitudinal, lateral, and vertical directions, the minimum intervals between the two aircraft in the longitudinal, lateral, and vertical directions are calculated using the following formulas: Where, d x d y and d z These are the minimum intervals between the two aircraft in the longitudinal, lateral, and vertical directions, respectively; σ x σ y and σ z denoted as the standard deviations of the first performance standard deviations of the two aircraft in the longitudinal, lateral, and vertical directions, respectively; 'a' indicates that when the actual longitudinal distance is less than 'a', the safety zones of the two aircraft overlap longitudinally; 'b' indicates that when the actual lateral distance is less than 'b', the safety zones of the two aircraft overlap laterally; 'c' indicates that when the actual vertical distance is less than 'c', the safety zones of the two aircraft overlap vertically.

[0012] The spatial distance between several aircraft is represented by a relative distance vector; the relative distance vector is: D = {d ij ,i、j=1,2,...n,i≠j}, where d ij The spatial distance between the i-th and j-th aircraft is calculated using the following formula: In the formula, (x i ,x j (x) represents the position coordinates of the two aircraft along the x-axis; (y) represents the position coordinates of the two aircraft along the y-axis. i ,y j () represents the coordinates of the two aircraft along the y-axis, and (z) represents the coordinates of the two aircraft along the z-axis. i ,z j ) represent the heights of the two aircraft along the z-axis;

[0013] by Let S be the objective function. The particle swarm optimization algorithm is used to optimize this function, yielding the number of aircraft that can be accommodated within a preset region while satisfying the minimum spacing requirement; where S... min (C) represents the standard deviation of the minimum spacing between two aircraft in the longitudinal, lateral, and vertical directions; Ω is the set of airspace geometric and topological constraints; α and β are weighting coefficients that control the importance of safety spacing and aircraft capacity in the overall optimization, respectively.

[0014] Optionally, the inner layer of the protection zone for each aircraft is determined based on the aircraft's fuselage size and safety redundancy coefficient, using the following formula:

[0015] R inner =1.1R span ;

[0016] wherein R inner is the radius of the inner layer of the protection zone, R span is the radius of the fuselage size of the aircraft.

[0017] Optionally, the maximum positioning error in the x-axis or y-axis direction caused by the onboard communication, navigation and surveillance system of the aircraft is used to determine the outer layer of the protection zone of each aircraft, and specifically comprises:

[0018] The positioning error in the x-axis direction caused by the onboard communication, navigation and surveillance system of the aircraft is calculated according to the following formula: wherein δ Cx , δ Nx and δ Sx respectively represent the communication capability error, the navigation capability error and the surveillance capability error in the x-axis direction;

[0019] The positioning error in the y-axis direction caused by the onboard communication, navigation and surveillance system of the aircraft is calculated according to the following formula: wherein δ Cy , δ Ny and δ Sy respectively represent the communication capability error, the navigation capability error and the surveillance capability error in the y-axis direction;

[0020] The outer layer of the protection zone is determined according to the following formula: R exterior = max(δ x , δ y ); wherein R exterior represents the radius of the outer layer of the protection zone.

[0021] Optionally, the inner layer of the protection zone and the outer layer of the protection zone are superimposed to obtain the calculation formula of the safety area of each aircraft as follows:

[0022] R = R inner + R exterior ;

[0023] wherein R represents the radius of the safety area; R inner represents the radius of the inner layer of the protection zone; and R exterior represents the radius of the outer layer of the protection zone.

[0024] Optionally, the calculation formula of the standard deviation of the first performance standard deviation in the longitudinal direction of two aircrafts is as follows:

[0025]

[0026] wherein σ xa standard deviation of the standard deviations of the first performance standard deviations of the two aircrafts in the longitudinal direction, σ1 represents the first performance standard deviation of the first aircraft in the longitudinal direction, and σ2 represents the first performance standard deviation of the second aircraft in the longitudinal direction.

[0027] Optionally, after the minimum separation distances of the two aircrafts in the longitudinal direction, the lateral direction and the vertical direction are respectively calculated according to the standard deviations of the standard deviations of the first performance standard deviations of the two aircrafts in the longitudinal direction, the lateral direction and the vertical direction, the method further comprises:

[0028] The minimum separation distances of the two aircrafts in the longitudinal direction, the lateral direction and the vertical direction are respectively divided by the obstacle avoidance accuracy values.

[0029] Optionally, when the optimization is performed by using the particle swarm optimization algorithm, the following is performed:

[0030] Each particle represents a three-dimensional separation configuration scheme;

[0031] The population represents a group of parallel evaluated separation configuration schemes;

[0032] The corresponding position vector x i = [S X , S Y , S Z ], S X , S Y , S Z respectively represent the minimum safety separation distances of the particle in the longitudinal direction, the lateral direction and the vertical direction.

[0033] In a second aspect, the present application provides a computer device, comprising a memory, a processor, and a computer program stored in the memory and executable on the processor, and the processor executes the computer program to implement the low-altitude vertical take-off and landing aircraft dynamic safety separation setting method in any one of the above.

[0034] In a third aspect, the present application provides a computer readable storage medium, which stores a computer program, and the computer program is executed by a processor to implement the low-altitude vertical take-off and landing aircraft dynamic safety separation setting method in any one of the above.

[0035] In a fourth aspect, the present application provides a computer program product, comprising a computer program, and the computer program is executed by a processor to implement the low-altitude vertical take-off and landing aircraft dynamic safety separation setting method in any one of the above.

[0036] According to the embodiments provided in the present application, the following technical effects are disclosed:

[0037] The application provides a low-altitude vertical take-off and landing aircraft dynamic safety interval setting method, equipment, medium and product, the method comprising: determining an inner layer of a protection zone of each aircraft according to a fuselage size of the aircraft and a safety redundancy coefficient; determining an outer layer of the protection zone of each aircraft according to maximum positioning errors in x-axis or y-axis directions caused by an onboard communication, navigation and surveillance system of the aircraft; superimposing the inner layer of the protection zone and the outer layer of the protection zone to obtain a safety area of each aircraft; calculating standard deviations of first performance standard deviations of two aircrafts in longitudinal, lateral and vertical directions respectively according to the first performance standard deviation of each aircraft; the first performance standard deviation is a standard deviation of communication performance, navigation performance, monitoring performance and obstacle avoidance performance of the aircraft; and calculating minimum intervals of the two aircrafts in the longitudinal, lateral and vertical directions respectively according to the standard deviations of the first performance standard deviations of the two aircrafts in the longitudinal, lateral and vertical directions, and the calculation formula is: wherein d x , d y and d z are minimum intervals of two aircrafts in longitudinal, lateral and vertical directions respectively; σ x , σ y and σ z respectively represent standard deviations of first performance standard deviations of the two aircrafts in longitudinal, lateral and vertical directions respectively; a represents that when an actual distance in the longitudinal direction is less than a, safety areas of the two aircrafts are overlapped in the longitudinal direction; b represents that when an actual distance in the lateral direction is less than b, the safety areas of the two aircrafts are overlapped in the lateral direction; and c represents that when an actual distance in the vertical direction is less than c, the safety areas of the two aircrafts are overlapped in the vertical direction; a relative distance vector is used to represent spatial distances between a plurality of aircrafts; the relative distance vector is D={d ij , i, j=1, 2,..., n, i≠j}, wherein d ij is a spatial distance between an i-th aircraft and a j-th aircraft, and the calculation formula is wherein (x i , x j ) respectively represent position coordinates of two aircrafts in the x-axis direction; (y i , y j ) respectively represent coordinates of the two aircrafts in the y-axis direction; (z i , z j ) respectively represent heights of the two aircrafts in the z-axis direction; and (z i , z j ) represent heights of the two aircrafts in the z-axis direction; and For the objective function, the particle swarm optimization algorithm is used for optimization, and the number of aircrafts that can be accommodated in the preset area under the premise of meeting the minimum interval is obtained; wherein, S min (C) represents the standard deviation of the minimum interval of two aircrafts in the longitudinal, lateral and vertical directions; Ω is the airspace geometry and topology constraint set; α and β are weight coefficients, respectively controlling the importance of safety distance and aircraft capacity in comprehensive optimization. According to the different performances of the aircrafts, the safety area around the aircrafts can change in real time, and the particle swarm optimization is performed according to the calculated minimum interval, so as to maximize the use of airspace resources. BRIEF DESCRIPTION OF DRAWINGS

[0038] In order to more clearly illustrate the technical solutions in the embodiments of the present application or the prior art, the drawings needed in the embodiments will be briefly introduced as follows. Obviously, the drawings in the following description are only some embodiments of the present application, and other drawings can also be obtained by those skilled in the art without creative labor.

[0039] Figure 1 A flowchart of a low-altitude vertical take-off and landing aircraft dynamic safety interval setting method provided by an embodiment of the present application.

[0040] Figure 2 A protection zone schematic diagram provided by an embodiment of the present application.

[0041] Figure 3 A process diagram for determining a protection zone provided by an embodiment of the present application.

[0042] Figure 4 A relationship diagram between the protection zone and the safety interval provided by an embodiment of the present application.

[0043] Figure 5 A timeline analysis diagram of the collision avoidance maneuver and system reaction of two aircrafts in the final approach phase provided by an embodiment of the present application.

[0044] Figure 6 A two-aircraft collision area analysis process diagram provided by an embodiment of the present application.

[0045] Figure 7 An obstacle avoidance distance diagram provided by an embodiment of the present application.

[0046] Figure 8 A collision interval and protection zone determination diagram provided by an embodiment of the present application.

[0047] Figure 9 A three-dimensional distribution diagram of an aircraft provided by an embodiment of the present application.

[0048] Figure 10 A cross-sectional view of a three-dimensional distribution of aircrafts is provided for an embodiment of the present application.

[0049] Figure 11 A flowchart of a solution process of a particle swarm optimization algorithm is provided for an embodiment of the present application.

[0050] Figure 12 A structural diagram of a computer device is provided for an embodiment of the present application. DETAILED DESCRIPTION

[0051] The technical solutions in the embodiments of the present application will be described clearly and completely below with reference to the drawings in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, rather than all the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without creative work fall within the scope of protection of the present application.

[0052] In order to cope with the limitations of the existing three-dimensional interval protection area technology, a dynamic three-dimensional interval protection area design scheme is proposed in the present application. The scheme can adjust the size of the three-dimensional interval protection area in real time, ensure that the aircraft is always in a safe state during flight, and maximize the use of airspace resources, thereby meeting the needs of future civil aviation field for aircraft safety supervision.

[0053] The safety area in the prior art is fixed and cannot change with CNS (Communication Navigation Surveillance). According to the different CNS capabilities, the safety area around the aircraft can change in real time in the present application. For example, when the navigation accuracy fluctuates, the safety area can also be changed through calculation.

[0054] The above-mentioned purposes, features and advantages of the present application can be more obvious and easy to understand. The present application will be described in further detail below with reference to the drawings and specific embodiments.

[0055] In an exemplary embodiment, as shown in Figure 1 A low-altitude vertical take-off and landing aircraft dynamic safety interval setting method is provided, including the following steps S1 to S7. Wherein:

[0056] S1, according to the fuselage size of the aircraft and the safety redundancy coefficient, the inner layer of the protection zone of each aircraft is determined.

[0057] In the present embodiment, a protection zone model of the vertical take-off and landing aircraft is established; and the safety area of the aircraft, i.e., the determination of the protection zone, is obtained.

[0058] Based on the double-layer protection zone of the aircraft dynamics characteristics, as followsFigure 2 and Figure 3 is shown, wherein the outer layer of the protection zone is the conflict alert layer, and the reachable range of the flight path of the intruder is determined by simulating the flight path of the intruder in different motion modes; the inner layer of the protection zone is the collision layer, and the aircraft specification parameters and the performance of the airborne equipment are referred to to meet the need of the aircraft body collision prevention under the condition of position uncertainty.

[0059] The aircraft collision avoidance process is divided into three stages: situation awareness, conflict prediction, and collision avoidance maneuver.

[0060] Based on the above stages, the aircraft double-layer protection zone is designed to simulate the collision avoidance process, and the outer layer of the protection zone is used for collision avoidance decision-making to prevent the distance from continuing to decrease to the inner layer of the protection zone. In view of the characteristics of the random flight speed and direction of the aircraft and the great flexibility of avoidance, the aircraft double-layer protection zone is designed, which specifically includes the outer conflict alert layer representing the reachable area of the flight path and the inner collision layer representing the position uncertainty of the aircraft. When the aircraft in the detection range perceives the real-time flight state information of the intruder (position, heading, speed, etc. are obtained through a trusted system such as an airborne sensor), the flight path of the intruder will be tracked, and when the intruder and the aircraft further approach to a certain distance (i.e. the outer layer of the protection zone), the aircraft will take flight measures to prevent the distance between the two aircrafts from further decreasing (i.e. the inner layer of the protection zone) to cause the aircraft body collision.

[0061] The outer layer of the protection zone is determined by predicting the reachable area of the flight path of the intruder. The reachable area of the flight path of the intruder represents the threat range that can be covered by the intruder within a given time, which changes dynamically with the maneuvering performance (such as turning speed, tilt angle) of the intruder. By reasonably predicting the reachable range of the intruder, the avoidance action can be triggered in time when the aircraft touches the outer layer of the protection zone, which can reduce the possibility of subsequent collision.

[0062] Design of the inner layer of the protection zone:

[0063] During the approach of the aircraft and the intruder, the relative position can be quickly calculated by the monitoring device. Due to the delay of the device, there will be positioning errors in the flight process. Therefore, the inner layer of the protection zone is set to R inner , which is multiplied by the safety redundancy coefficient to ensure that the actual position of the aircraft is still located in the inner layer of the protection zone in the worst case. The calculation formula is: span

[0064] R inner = 1.1R span ;

[0065] In the formula, R inner is the radius of the inner layer of the protection zone, and R span ​R is the radius of the fuselage size of the aircraft. In the formula, the coefficient of the reference aircraft fuselage size is set to 1.1 (safety redundancy coefficient), aiming to provide additional safety margin for meteorological factors, operation margin and other error factors.

[0066] S2, the maximum positioning error in the x-axis or y-axis direction caused by the airborne communication, navigation and surveillance system of the aircraft, determines the outer layer of the protection zone of each aircraft.

[0067] The embodiment is based on the existing performance-based communication navigation surveillance (CNS, Communication Navigation Surveillance) concept. The position errors caused by communication, navigation, surveillance and other factors are independent of each other and subject to a Gaussian distribution with a mean of 0. Taking performance-based navigation as an example, the required navigation performance (RNP) RNP-q represents the probability that the aircraft deviation error is less than q meters is 95%. The required navigation performance RNP-q, the required communication performance RCP-w and the required surveillance performance RSP-r (the meaning of w and r is less than w meters and less than r meters) satisfy: C N S (C is communication, N is navigation, and S is surveillance) respectively:

[0068]

[0069] The positioning error δ x in the x-axis direction caused by the airborne communication, navigation and surveillance system is:

[0070]

[0071] In the formula, δ Cx , δ Nx and δ Sx represent the communication capability error, navigation capability error and surveillance capability error in the x-axis direction respectively.

[0072] The positioning error δ y in the y-axis direction is:

[0073]

[0074] In the formula, δ Cy , δ Ny and δ Sy represent the communication capability error, navigation capability error and surveillance capability error in the y-axis direction respectively. The CNS capabilities of the aircraft in different directions are different, so here the x and y axes are distinguished.​​

[0075] Can be calculated

[0076] R exterior =max(δ x ,δ y );

[0077] In the formula, R exterior This indicates the radius of the outer layer of the protected area.

[0078] S3. Superimpose the inner layer and the outer layer of the protected area to obtain the safe zone for each aircraft.

[0079] Overall protected area (safe zone):

[0080] R = R inner +R exterior ;

[0081] Where R represents the radius of the safe zone; R inner R represents the inner radius of the protected area. exterior This indicates the radius of the outer layer of the protected area.

[0082] For example:

[0083] The route positioning accuracy (i.e., the navigation performance accuracy expected to be achievable 95% of the time is q meters) is defined as q = 15, 10, and 5, corresponding to low, medium, and high accuracy, respectively. The parameters of the EHang 216-S model are selected as shown in Table 1 below:

[0084] Table 1. Parameters of EHang 216-S Model

[0085]

[0086] Based on the safety zone (total protected area) obtained above, the collision risk between aircraft is determined; that is, what distance is acceptable between two aircraft. The collision probability is required to be below 5%, and then the safe separation distance is calculated. Figure 4 As shown, Figure 4 In the middle, d represents the safety interval.

[0087] 1. Determining obstacle avoidance accuracy (determining the 95% parameter).

[0088] The RAP (Requirement Avoidance Performance) definition requires that the aircraft achieve the expected obstacle avoidance accuracy for at least 95% of its flight time, based on the following precise calculations and verifications.

[0089] ① Collision area:

[0090] By analyzing the timeline of the collision avoidance maneuvers and system reactions performed by the two aircraft during the final approach phase, it can be roughly divided into the following categories: Figure 5 The four parts shown.

[0091] The safe distance required from detecting a conflict to successfully avoiding it is:

[0092] d = d avoid +c(t tracking +t sep +t auto );

[0093] d avoid d is the distance the two aircraft should be separated at the start of the collision avoidance maneuver, such that the separation when they reach their closest point of impact (PCA) is greater than the radius of the combined collision zone; d is the safety separation; c is the relative speed between the two aircraft; t auto The time required for the autonomous driving system to process; t sep t represents the interval service response time; tracking The time required for detection and tracking.

[0094] The collision zone considers the worst-case scenario (180° oncoming flight) and the required clearance, i.e., it calculates the safe clearance that the collision zone can satisfy any remaining conditions, such as... Figure 6 As shown, V1 and V2 represent the velocities of the two aircraft, respectively, and d min This indicates the minimum interval.

[0095] Considering the accuracy standard of the aircraft's positioning method, and assuming that the above influencing factors follow a normal distribution, the total error is:

[0096]

[0097] Where σ avoid The standard deviation of the distance required for collision avoidance maneuvers; σ tracking The standard deviation of the time required for detection and tracking; σ sep σ is the standard deviation of the interval service response time; pilot The standard deviation of the time required for the driver or autonomous driving system to process.

[0098] Since the safety distance used here is the one obtained using the combined collision zone, the intruding aircraft is still considered a point mass. When the point mass enters the collision volume, it is considered that a collision has occurred between the two aircraft. Therefore, the instantaneous collision volume is:

[0099]

[0100] Wherein, X, Y, and Z are the conflict distances in the horizontal, vertical, and longitudinal directions, respectively (in this embodiment, the conflict distance is the safety interval).

[0101] 2. Accuracy calculation:

[0102] Next, the obstacle avoidance accuracy is confirmed, so as to reduce the collision space on the basis of the CNS performance, so that more aircrafts can be accommodated in the same airspace, and the airspace efficiency and traffic are improved.

[0103] S4, according to the first performance standard deviation of each aircraft, the standard deviation of the first performance standard deviation of the two aircrafts in the longitudinal, lateral and vertical directions is calculated respectively; the first performance standard deviation is the standard deviation of the communication performance, navigation performance, monitoring performance and obstacle avoidance performance of the aircraft.

[0104] S5, according to the standard deviation of the first performance standard deviation of the two aircrafts in the longitudinal, lateral and vertical directions, the minimum separation of the two aircrafts in the longitudinal, lateral and vertical directions is calculated, and the calculation formula is: Wherein, d x , d y and d z are the minimum separation of the two aircrafts in the longitudinal, lateral and vertical directions; σ x , σ y and σ z respectively represent the standard deviation of the first performance standard deviation of the two aircrafts in the longitudinal, lateral and vertical directions; a represents that when the actual distance in the longitudinal direction is less than a, the safety area of the two aircrafts is overlapped in the longitudinal direction; b represents that when the actual distance in the lateral direction is less than b, the safety area of the two aircrafts is overlapped in the lateral direction; c represents that when the actual distance in the vertical direction is less than c, the safety area of the two aircrafts is overlapped in the vertical direction.

[0105] According to the above obstacle avoidance accuracy (i.e. the above obtained 95%), PBA (Performance based on avoidance) is proposed on the basis of PBC / PBN / PBS, which is a standard based on obstacle avoidance performance, so as to obtain the final dx_final, dy_final and dz_final (the minimum separation in three directions), as shown in the following formula: Figure 7

[0106] RCP, RNP, RSP and RAP define that the aircraft can achieve the expected communication, navigation, monitoring and obstacle avoidance accuracy for at least 95% of the flight time. Based on the parameters of CNSA (National Space Agency), the following formula is satisfied:

[0107]

[0108] Wherein, σ C , σ N ​, σ S , σ A respectively represent the standard deviation of communication, navigation, surveillance, obstacle avoidance, q, w, r, e respectively represent the RCP, RNP, RSP, RAP value, v represents the aircraft speed.

[0109] The square of the surveillance, communication, navigation, obstacle avoidance can obtain the first performance standard deviation σ1, σ2 of two aircraft respectively (the subscript 1 represents aircraft 1, and the subscript 2 represents aircraft 2), as follows:

[0110]

[0111] The International Civil Aviation Organization (ICAO) stipulates that the safety target level of collision of aircraft in any one direction in the longitudinal, lateral and vertical directions in the airspace is 5x10 -9 / flight hour. The different situations of the collision risk change corresponding to the interval change in the three directions under different navigation accuracy are studied.

[0112] Under the CNSA capability:

[0113] The following formula is satisfied, and the minimum longitudinal, lateral and vertical intervals d x , d y , d z are calculated; wherein d x is the minimum interval of two aircraft along the x-axis (longitudinal), d y is the minimum interval of two aircraft along the y-axis (lateral), and d z is the minimum interval of two aircraft along the z-axis (vertical).

[0114]

[0115] wherein σ represents the standard deviation of the first performance standard deviation of two aircraft in the longitudinal direction, and σ y , σ z respectively represent the standard deviation of the first performance standard deviation of two aircraft in the lateral direction and the standard deviation of the first performance standard deviation of two aircraft in the vertical direction. The formulas of the three parameters are the same, but the difference is that there are different σ C , σ N , σ S , σ P values in the XYZ three different axes.

[0116] When the navigation accuracy q=15, 10, 5, according to , the corresponding standard deviation is σ y =7.65, 5.1, 2.55, and according to , when d y =0, Py (0) = 0.5382, 0.7304, 0.9739. 0.5382 (low accuracy), 0.7304 (medium accuracy), 0.9739 (high accuracy). P y (0) is the probability when the lateral distance d y between two aircrafts is 0, that is, the probability of lateral overlap.

[0117] Similarly, P x (0), P z (0) can be obtained. According to three different accuracies, the safety region R under three accuracies can be obtained.

[0118] Set both aircrafts as Yihang 216-s model, whose data table is as above, the standard deviation σ1 of aircraft 1 = 5m, the standard deviation σ2 of aircraft 2 = 2m, the speed standard deviation σ v = 2km / h. Under different accuracies, σ x , σ y , σ z can be obtained.

[0119] Under the low accuracy (q = 15m) navigation condition, the minimum longitudinal, lateral and vertical intervals are 45.2m, 68.0m and 15.8m respectively.

[0120] Under the medium accuracy (q = 10m) navigation condition, the minimum longitudinal, lateral and vertical intervals are 45.5m, 47.2m and 16m respectively.

[0121] Under the high accuracy (q = 5m) navigation condition, the minimum longitudinal, lateral and vertical intervals are 45.9m, 26.4m and 16.1m respectively.

[0122] Consider the obstacle avoidance capability:

[0123] Since the obstacle avoidance accuracy is 95%, it can be considered that 95% is expanded on the basis of the original safety interval to ensure that the aircraft can safely avoid:

[0124] d x_final = d x ÷ 0.95

[0125] d y_final = d y ÷ 0.95

[0126] d z_final = d z ÷ 0.95

[0127] Therefore, under the high accuracy (q = 5m) navigation condition, the minimum longitudinal, lateral and vertical intervals are 43.605m, 25.08m and 15.295m respectively.

[0128] Based on the collision risk obtained from the above steps, the safe zone capacity can be calculated; such as Figure 8 As shown, under high-precision navigation conditions, the minimum longitudinal, lateral, and vertical spacings are 43.605m, 25.08m, and 15.295m, respectively. It should be noted that these spacings refer to the spacing between the outer layers of the aircraft's protected zone.

[0129] Within an ellipsoidal region measuring 44.41m in length, 41.86m in height, and 39.31m in width, the longitudinal, lateral, and vertical distances between any two aircraft are 43.605m, 25.08m, and 15.295m, respectively. Consider how many aircraft can be placed in a 1km x 1km x 1km area. Using MATLAB, the result is 2970 aircraft. A visualization is shown below. Figure 9 and Figure 10 As shown.

[0130] S6. Use a relative distance vector to represent the spatial distance between several aircraft; the relative distance vector is: D = {d ij ,i、j=1,2,...n,i≠j}, where d ij The spatial distance between the i-th and j-th aircraft is calculated using the following formula: In the formula, i and j represent two aircraft, for example, (x i ,x j (x) represents the position coordinates of the two aircraft along the x-axis; (y) represents the position coordinates of the two aircraft along the y-axis. i ,y j () represents the coordinates of the two aircraft along the y-axis, and (z) represents the coordinates of the two aircraft along the z-axis. i ,z j ) represent the heights of the two aircraft along the z-axis.

[0131] S7, with Let S be the objective function. The particle swarm optimization algorithm is used to optimize this function, yielding the number of aircraft that can be accommodated within a preset region while satisfying the minimum spacing requirement; where S... min (C) represents the standard deviation of the minimum spacing between two aircraft in the longitudinal, lateral, and vertical directions; Ω is the set of airspace geometric and topological constraints; α and β are weighting coefficients that control the importance of safety spacing and aircraft capacity in the overall optimization, respectively.

[0132] This embodiment optimizes the aircraft distance based on the aforementioned safety capacity, and further enhances the obstacle avoidance capability in the safe area based on this distance.

[0133] Based on the aforementioned safe capacity, further consideration is given to obstacle avoidance accuracy and airspace constraints to calculate a more accurate airspace capacity, thereby improving the obstacle avoidance capability in safe areas.

[0134] Let the relative distance vector of any aircraft be: D = {d ij , i, j = 1, 2,..., n, i≠j}, where d ij is the spatial distance between the ith and jth aircraft, and is calculated by

[0135] A capacity-distance mapping function C = f(D) is established to represent the maximum safe capacity under the current distance configuration. The main purpose is to convert the distance configuration D between each aircraft into a quantifiable "safe capacity" indicator C, which can quantitatively assess how many aircraft this airspace can accommodate at most without violating the minimum safety distance under the given distance configuration. The aircraft protection zone is an ellipsoid, and this method is a theoretical maximum capacity estimation, considering the dense packing of aircraft without gaps (which is not realistic in practice).

[0136] A packing coefficient η can be considered to modify f(D) 实际 = f(D)·η; and an optimization objective function is constructed:

[0137]

[0138] where S min (C) is the lower limit of the safe separation distance in this airspace (considering the obstacle avoidance accuracy), which can be obtained from the safe separation table or calculation (where Sx = dx_final, Sy = dy_final, and Sz = dz_final), and Ω is the set of airspace geometry and topology constraints, including airspace boundaries, flight altitude layers, and other restriction conditions.

[0139] α and β are weight coefficients that control the importance of the two objectives (safe distance and aircraft capacity) in the comprehensive optimization. α is the weight coefficient of the "minimum separation" term, and the larger the value, the more the optimization favors increasing the minimum separation, emphasizing obstacle avoidance safety; the smaller the value, the less attention is paid to safety redundancy. β is the weight coefficient of the "capacity" term, and the larger the value, the more the optimization favors improving the formation capacity C, emphasizing high throughput or dense formation; the smaller the value, the more it values maximizing the minimum separation.

[0140] The function can be solved using a particle swarm optimization algorithm for this problem, and the core iterative formula is:

[0141]

[0142] where D k and v k are the distance configuration and velocity vector of the kth generation, p k is the individual optimal solution, g k is the global optimal solution, w, c1, and c2 are algorithm parameters, and r1 and r2 are uniformly distributed in (0, 1).

[0143] The "population" in PSO refers to a set of all candidate solutions (particles), each particle representing a three-dimensional spacing configuration scheme D, and the population is a set of parallel evaluated spacing configuration schemes; each "individual" in the population, i.e., a particle, carries the position of the current solution and the historical optimal information, which corresponds to the position vector x in the present application i X Y Z X Y Z respectively represent the longitudinal, lateral and vertical minimum safety spacing corresponding to the particle, and the individual optimal is p i ; for each dimension, S X Y Z The upper and lower bounds need to be set to ensure physical feasibility and safety requirements, and the position x i (0) of each particle in each dimension adopts a uniform random distribution in the above boundary interval; the velocity v i determines the position change of the next generation of particles, and when the velocity is set, the inertia weight w represents the ability to control the particle to search in the current velocity direction, and a velocity boundary is also set to prevent the particle from flying out of the solution space.

[0144] The solution flowchart is shown in Figure 11 , and the optimal spacing configuration D between the aircrafts can be obtained through calculation.

[0145] Compared with the traditional CNS and collision method, the present embodiment has the following three aspects of improvement:

[0146] ① Safety is improved:

[0147] By dynamically adjusting the size of the three-dimensional spacing protection area according to the flight state and environment, the aircraft can always be in a safe state. Compared with the traditional fixed three-dimensional spacing protection area, this scheme can respond to complex and changing flight environments in real time, avoiding waste of airspace resources. When flying in an open area, the three-dimensional spacing protection area is reduced, improving airspace utilization; when encountering potential risks, the range of the three-dimensional spacing protection area is timely expanded, effectively protecting flight safety. In addition, the scheme introduces a flight method based on 4D trajectory and performance evaluation mark (PBC / PBN / PBS / PBA), ensuring that the aircraft realizes trajectory consistency and safe separation during flight, reducing the risk of collision.

[0148] ② Flight capacity is increased:

[0149] ​​​​​​​​The scheme realizes the quantification of collision risk by dynamically adjusting the risk volume. When the risk area appears, the collision avoidance measures can be triggered immediately to ensure the accuracy and reliability of the flight mission. In the open area, the three-dimensional interval protection area is reduced to improve the airspace utilization rate and thus increase the flight capacity. Meanwhile, considering the communication delay, environmental interference and other factors, the scheme can more accurately reflect the uncertainty in flight and provide a reliable basis for collision risk assessment.

[0150] ③Adaptive enhancement:

[0151] The scheme combines the sensors, navigation system and collision avoidance function of the aircraft organically, can adjust the flight strategy in real time according to the information fed back by the sensors, and enhances the adaptability of the aircraft in complex environment. When facing different flight environments and potential risks, the flight path and collision avoidance strategy can be flexibly adjusted to improve the initiative and accuracy of flight control.

[0152] In an exemplary embodiment, a computer device, which can be a server or a terminal, is provided, and an internal structure diagram thereof can be as shown in Figure 12 The computer device includes a processor, a memory, an input / output interface (I / O) and a communication interface. The processor, the memory and the input / output interface are connected through a system bus, and the communication interface is connected to the system bus through the input / output interface. The processor of the computer device is used to provide computing and control capabilities. The memory of the computer device includes a non-volatile storage medium and an internal memory. The non-volatile storage medium stores an operating system, a computer program and a database. The internal memory provides an environment for the operation of the operating system and the computer program in the non-volatile storage medium. The input / output interface of the computer device is used to exchange information between the processor and external devices. The communication interface of the computer device is used to communicate with external terminals through network connection. The computer program is executed by the processor to implement a method for dynamically setting a safety interval of a low-altitude vertical take-off and landing aircraft.

[0153] Those skilled in the art can understand that Figure 12 The structure shown in the figure is only a block diagram of part of the structure related to the scheme of the present application, and does not constitute a limitation on the computer device to which the scheme of the present application is applied. The specific computer device can include more or fewer components than those shown in the figure, or combine certain components, or have a different arrangement of components.

[0154] In an exemplary embodiment, a computer device is also provided, including a memory and a processor, the memory storing a computer program, and the processor executing the computer program to implement the steps in the above method embodiments.

[0155] In an exemplary embodiment, a computer readable storage medium storing a computer program is provided, the computer program, when executed by a processor, implements the steps in the above method embodiments.

[0156] In an exemplary embodiment, a computer program product is provided, comprising a computer program, which, when executed by a processor, implements the steps in the above method embodiments.

[0157] It should be noted that the user information (including but not limited to user equipment information, user personal information, etc.) and data (including but not limited to data for analysis, stored data, displayed data, etc.) involved in the present application are all information and data authorized by the user or authorized by all parties, and the collection, use and processing of related data need to comply with relevant regulations.

[0158] It can be understood by those skilled in the art that all or part of the processes in the above embodiments can be completed by a computer program instructing related hardware. The computer program can be stored in a non-volatile computer readable storage medium. When the computer program is executed, it can include the processes of the above embodiments. Any reference to memory, database or other medium used in the embodiments provided by the present application can include at least one of non-volatile and volatile memory. Non-volatile memory can include read-only memory (ROM), magnetic tape, floppy disk, flash memory, optical memory, high-density embedded non-volatile memory, resistive memory (ReRAM), magnetoresistive random access memory (MRAM), ferroelectric memory (FRAM), phase change memory (PCM), graphene memory, etc. Volatile memory can include random access memory (RAM) or external cache memory, etc. As an illustration but not limitation, RAM can be in various forms, such as static random access memory (SRAM) or dynamic random access memory (DRAM), etc.

[0159] The database involved in each of the embodiments provided in the present application can include at least one of a relational database and a non-relational database. The non-relational database can include a distributed database based on a blockchain, and the like, without being limited thereto. The processor involved in each of the embodiments provided in the present application can be a general-purpose processor, a central processing unit, a graphics processing unit, a digital signal processor, a programmable logic device, a data processing logic device based on quantum computing, and the like, without being limited thereto.

[0160] The technical features of the above embodiments can be combined in any manner. To make the description concise, all possible combinations of the technical features in the above embodiments are not described, but it should be considered that any combination of the technical features is within the scope of the present disclosure, as long as there is no contradiction.

[0161] The principles and implementation manners of the present application are described by using specific examples herein, and the above embodiments are only used to help understand the method of the present application and its core idea. Meanwhile, for those skilled in the art, the specific implementation manners and application ranges can be changed according to the idea of the present application. In summary, the content of the present description should not be understood as a limitation of the present application.

Claims

1. A method for setting dynamic safety separations for low-altitude vertical takeoff and landing aircraft, the method comprising: The application comprises the following steps: According to the fuselage size of the aircraft and the safety redundancy coefficient, the inner layer of the protection zone of each aircraft is determined; According to the maximum positioning error in the x-axis or y-axis direction caused by the onboard communication, navigation and surveillance system of the aircraft, the outer layer of the protection zone of each aircraft is determined; The inner layer of the protection zone and the outer layer of the protection zone are superimposed to obtain the safety area of each aircraft; According to the first performance standard deviation of each aircraft, the standard deviation of the first performance standard deviation of the two aircrafts in the longitudinal, lateral and vertical directions is calculated respectively; The first performance standard deviation is the standard deviation of the communication performance, navigation performance, surveillance performance and obstacle avoidance performance of the aircraft; According to the standard deviation of the first performance standard deviation of the two aircrafts in the longitudinal, lateral and vertical directions, the minimum separation of the two aircrafts in the longitudinal, lateral and vertical directions is calculated respectively, and the calculation formula is: where d x , d y , and d z are the minimum separation of two aircrafts in longitudinal, lateral, and vertical directions, respectively; σ x , σ y , and σ z are the standard deviations of the first performance standard deviations of two aircrafts in longitudinal, lateral, and vertical directions, respectively; a indicates that the safety regions of two aircrafts have longitudinal overlap when the actual longitudinal distance is less than a; b indicates that the safety regions of two aircrafts have lateral overlap when the actual lateral distance is less than b; and c indicates that the safety regions of two aircrafts have vertical overlap when the actual vertical distance is less than c. The spatial distance between several aircrafts is represented by a relative distance vector D = {d ij ,i,j = 1,2,..., n, i ≠ j}, wherein d ij is the spatial distance between the ith and jth aircrafts, and the calculation formula is wherein (x i , x j ) represent the position coordinates of the two aircrafts in the x-axis direction, respectively; (y i , y j ) represent the coordinates of the two aircrafts in the y-axis direction, respectively; and (z i , z j ) represent the heights of the two aircrafts in the z-axis direction, respectively. To The particle swarm optimization algorithm is used for optimization with the target function, to obtain the number of aircrafts that can be accommodated in the preset area under the premise of meeting the minimum interval; wherein, S min (C) represents the standard deviation of the minimum interval of two aircrafts in the longitudinal, lateral and vertical directions; Ω is the airspace geometry and topology constraint set; and α and β are weight coefficients, respectively controlling the importance of safety interval and aircraft capacity in comprehensive optimization.

2. The low-voidage VTOL aircraft dynamic safety separation setting method according to claim 1, characterized in that, According to the fuselage size of the aircraft and the safety redundancy coefficient, the inner layer of the protection zone of each aircraft is determined, and the calculation formula is: R inner = 1.1R span ; where R inner is the radius of the inner layer of the protected zone, and R span is the radius of the fuselage size of the aircraft.

3. The method of claim 1, wherein, According to the maximum positioning error in the x-axis or y-axis direction caused by the onboard communication, navigation and surveillance system of the aircraft, the outer layer of the protection zone of each aircraft is determined, which specifically comprises: The positioning error in the x-axis direction caused by the onboard communication, navigation and surveillance system of the aircraft is calculated, and the calculation formula is: where δ Cx , δ Nx , and δ Sx respectively represent the communication capability error, the navigation capability error, and the monitoring capability error in the x-axis direction; The positioning error in the y-axis direction caused by the onboard communication, navigation and surveillance system of the aircraft is calculated, and the calculation formula is: where δ Cy , δ Ny , and δ Sy represent the communication capability error, the navigation capability error, and the surveillance capability error in the y-axis direction, respectively. The outer layer of the protection zone is determined, and the calculation formula is: R exterior = max(δ x , δ y ); in the formula, R exterior represents the radius of the outer layer of the protection zone.

4. The method of claim 1, wherein, The calculation formula for superimposing the inner layer of the protection zone and the outer layer of the protection zone to obtain the safety area of each aircraft is: R = R inner + R exterior ; where R represents the radius of the safety zone; R inner represents the inner radius of the protection zone; R exterior represents the outer radius of the protection zone.

5. The method of claim 1, wherein, The calculation formula for calculating the standard deviation of the first performance standard deviation of the two aircrafts in the longitudinal direction is: where σ x denotes the standard deviation of the standard deviations of the first performance in the longitudinal direction of the two aircraft, σ1 denotes the standard deviation of the first performance in the longitudinal direction of the first aircraft, and σ2 denotes the standard deviation of the first performance in the longitudinal direction of the second aircraft.

6. The method of claim 1, wherein, After the minimum separation of the two aircrafts in the longitudinal, lateral and vertical directions is calculated according to the standard deviation of the first performance standard deviation of the two aircrafts in the longitudinal, lateral and vertical directions, the minimum separation of the two aircrafts in the longitudinal, lateral and vertical directions is calculated respectively, and the calculation formula is: The minimum separation of the two aircrafts in the longitudinal, lateral and vertical directions is divided by the obstacle avoidance accuracy value respectively.

7. The method of claim 1, wherein, When the particle swarm optimization algorithm is used for optimization: Each particle represents a three-dimensional spacing configuration scheme; The population represents a group of parallel evaluated spacing configuration schemes; corresponding position vector x i = [S X , S Y , S Z ], S X , S Y , S Z respectively represent the minimum safety distance of the longitudinal, lateral, and vertical direction corresponding to the particle.

8. A computer device comprising: The memory, the processor and the computer program stored in the memory and capable of running on the processor, characterized in that the processor executes the computer program to realize the low-altitude vertical take-off and landing aircraft dynamic safety interval setting method of any one of claims 1-7.

9. A computer-readable storage medium having stored thereon a computer program, characterized in that, The computer program is executed by the processor to realize the low-altitude vertical take-off and landing aircraft dynamic safety interval setting method of any one of claims 1-7.

10. A computer program product comprising a computer program, characterized in that, The computer program is executed by the processor to realize the low-altitude vertical take-off and landing aircraft dynamic safety interval setting method of any one of claims 1-7.

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