Method and apparatus for four-dimensional trajectory prediction with multiple required time of arrival constraints

Abstract

The application relates to a multi-point required time of arrival limited four-dimensional track prediction method and device, wherein the method comprises the following steps: determining a speed adjustable range of different flight stages; acquiring an initial time window of a time of arrival of each waypoint; reserving a required time of arrival limit of a waypoint in the initial time window, and calculating a shrinked time window under each reserved required time of arrival limit; reserving a constraint required time of arrival limit on a waypoint which can be simultaneously realized according to the input priority according to the shrinked time window; and generating a track satisfying the constraint required time of arrival limit on the waypoint. Thus, the problems in the prior art that the arrival time limit on multiple waypoints in different flight stages is rarely considered, the optimization method cannot effectively solve the situation that the arrival time limits of multiple input waypoints cannot be simultaneously realized, and the solving of the optimization problem usually requires a long calculation time are solved.

Description

Technical Field

[0001] This application relates to the field of air traffic management technology, and in particular to a four-dimensional trajectory prediction method and device for multi-point arrival time constraints. Background Technology

[0002] With increasing airspace congestion and rising air traffic volume, trajectory-based operations are becoming the next generation of air traffic management. This requires advanced flight management systems to predict the four-dimensional trajectory of an aircraft based on the flight plan provided by air traffic control. According to the ARINC 702A standard, the trajectory prediction function in a flight management system can be described as: generating a flyable trajectory that conforms to aircraft dynamics and airspace restrictions based on the input flight plan (including horizontal plan and some vertical parameters) and real-time airspace restrictions issued by air traffic control. Furthermore, when required time of arrival (RTA) constraints are imposed at waypoints, the arrival times at waypoints on the trajectory can be controlled to generate a trajectory that meets the required arrival time constraints.

[0003] In related technologies, arrival time constraints at a single waypoint within a specific flight phase (such as the descent phase) are typically considered, or arrival time constraints at multiple waypoints during the cruise phase are considered, and optimization methods are used to generate tracks that meet the time constraints.

[0004] However, related technologies rarely consider the situation where there are arrival time constraints at multiple waypoints in different flight phases, and the optimization methods cannot effectively solve the situation where the arrival time constraints of multiple waypoints cannot be met simultaneously. Moreover, solving optimization problems usually requires a long computation time, which urgently needs to be improved. Summary of the Invention

[0005] This application provides a four-dimensional trajectory prediction method and apparatus for multiple waypoint arrival time constraints, in order to solve the limitations of related technologies when dealing with the problem of arrival time constraints of multiple waypoints at different flight stages, which cannot handle the situation where multiple waypoint RTA constraints cannot be achieved simultaneously.

[0006] The first aspect of this application provides a four-dimensional trajectory prediction method for multiple required arrival time constraints, comprising the following steps: determining the adjustable speed range for different flight stages; based on the adjustable speed range for different flight stages, calculating the earliest and latest arrival times for each waypoint using the fastest and slowest speed schemes for each flight stage to obtain an initial time window for the arrival time of each waypoint; retaining the required arrival time constraints for waypoints within the initial time window, and calculating a contracted time window for each retained required arrival time constraint; retaining the required arrival time constraints for waypoints that can be simultaneously achieved according to the input priority based on the contracted time window; and generating a trajectory that satisfies the required arrival time constraints for waypoints.

[0007] Optionally, in one embodiment of this application, determining the adjustable speed range for different flight phases includes: obtaining the maximum climb rate, minimum climb rate, maximum climb Mach number, minimum climb Mach number, maximum cruise Mach number, minimum cruise Mach number, maximum descent Mach number, minimum descent Mach number, maximum descent rate, and minimum descent rate based on aircraft performance limitations and air traffic control limitations.

[0008] Optionally, in one embodiment of this application, after retaining the required arrival time limit for waypoints within the initial time window, the method further includes: returning to air traffic control to constrain the required arrival time limit for waypoints outside the initial time window.

[0009] Optionally, in one embodiment of this application, the calculation of the contraction time window under each required arrival time constraint includes: calculating the contraction of arrival time windows at other waypoints when the required arrival time at one waypoint is satisfied, and determining the contraction time window.

[0010] Optionally, in one embodiment of this application, generating a track that satisfies the arrival time limit required by waypoint constraints includes: calculating the speed between every two waypoint constraint arrival time points from front to back based on the simultaneously achievable waypoint constraint arrival time limit, in order to generate the track.

[0011] A second aspect of this application provides a four-dimensional trajectory prediction device for multiple required arrival time constraints, comprising: a determination module for determining the adjustable speed range for different flight stages; an acquisition module for calculating the earliest and latest arrival times at each waypoint based on the adjustable speed range for each flight stage, using the fastest and slowest speed schemes for each flight stage, to obtain an initial time window for the arrival time of each waypoint; a calculation module for retaining the required arrival time constraints of waypoints within the initial time window, and calculating a contracted time window for each retained required arrival time constraint; a retention module for retaining the required arrival time constraints of waypoints that can be simultaneously achieved according to the input priority based on the contracted time window; and a generation module for generating a trajectory that satisfies the required arrival time constraints of waypoints.

[0012] Optionally, in one embodiment of this application, the determining module is further configured to obtain the maximum climb rate, minimum climb rate, maximum climb Mach number, minimum climb Mach number, maximum cruise Mach number, minimum cruise Mach number, maximum descent Mach number, minimum descent Mach number, maximum descent rate, and minimum descent rate based on aircraft performance limitations and air traffic control limitations.

[0013] Optionally, in one embodiment of this application, it further includes: a return module for returning to air traffic control the required arrival time limit for constrained waypoints outside the initial time window.

[0014] Optionally, in one embodiment of this application, the calculation module includes: a determining unit, configured to calculate the situation where the arrival time window at other waypoints shrinks when the required arrival time at a waypoint is satisfied, and to determine the shrinking time window.

[0015] Optionally, in one embodiment of this application, the generation module includes: a generation unit, used to calculate the speed between the required arrival times of constraints on every two waypoints from front to back based on the arrival time limits required for constraints on waypoints that can be simultaneously achieved, so as to generate the track.

[0016] A third aspect of this application provides an electronic device, including: a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein the processor executes the program to implement a four-dimensional trajectory prediction method for multi-point arrival time constraints as described in the above embodiments.

[0017] A fourth aspect of this application provides a computer-readable storage medium storing a computer program that, when executed by a processor, implements the four-dimensional trajectory prediction method for multi-point arrival time constraints as described above.

[0018] This application's embodiments can calculate a contraction time window when setting RTA constraints at multiple points along a flight path, and retain the arrival time constraints required for constraints at waypoints that can be simultaneously met according to the input priority. This generates a track that satisfies the arrival time constraints at waypoints, enabling the handling of situations with arrival time constraints at multiple waypoints, thus offering greater applicability and faster processing speed. This solves the problems in related technologies, such as the lack of consideration for arrival time constraints at multiple waypoints in different flight phases, the inability of optimization methods to effectively address situations where the arrival time constraints of multiple waypoints cannot be met simultaneously, and the typically long computation time required to solve optimization problems.

[0019] Additional aspects and advantages of this application will be set forth in part in the description which follows, and in part will be obvious from the description, or may be learned by practice of this application. Attached Figure Description

[0020] The above and / or additional aspects and advantages of this application will become apparent and readily understood from the following description of the embodiments taken in conjunction with the accompanying drawings, wherein:

[0021] Figure 1 This is a flowchart of a four-dimensional trajectory prediction method for multi-point arrival time constraints provided in an embodiment of this application;

[0022] Figure 2 This is a flowchart illustrating the retention and speed adjustment of multiple waypoint RTA limits in a four-dimensional trajectory prediction method for multiple point arrival time constraints according to an embodiment of this application.

[0023] Figure 3 This is a schematic diagram of time window contraction for a four-dimensional trajectory prediction method with multi-point arrival time constraints according to an embodiment of this application;

[0024] Figure 4 A simplified time window shrinkage diagram of a four-dimensional trajectory prediction method for multi-point arrival time constraints according to an embodiment of this application;

[0025] Figure 5 This diagram illustrates four relationships between RTAs based on a contracted time window in a four-dimensional trajectory prediction method for multi-point required arrival time constraints according to embodiments of this application.

[0026] Figure 6 A flowchart illustrating the method for predicting four-dimensional tracks with multiple required arrival time constraints according to embodiments of this application, which preserves RTA constraints according to their importance;

[0027] Figure 7 This is a flowchart illustrating a four-dimensional trajectory prediction method for multi-point time-of-arrival constraints according to embodiments of this application, predicting trajectories from front to back under multi-point RTA constraints.

[0028] Figure 8 This is a flowchart illustrating the velocity iteration between two RTAs in a four-dimensional trajectory prediction method for multi-point required arrival time constraints according to embodiments of this application;

[0029] Figure 9 This is a schematic diagram of the velocity update direction between the climb and cruise two RTA points according to the four-dimensional trajectory prediction method for multi-point required arrival time constraints in accordance with the embodiments of this application.

[0030] Figure 10 This is an example diagram of a four-dimensional trajectory prediction device for multi-point arrival time constraints according to an embodiment of this application;

[0031] Figure 11 This is a schematic diagram of the structure of an electronic device according to an embodiment of this application. Detailed Implementation

[0032] The embodiments of this application are described in detail below. Examples of these embodiments are shown in the accompanying drawings, wherein the same or similar reference numerals denote the same or similar elements or elements having the same or similar functions throughout. The embodiments described below with reference to the accompanying drawings are exemplary and intended to explain this application, and should not be construed as limiting this application.

[0033] The following describes a four-dimensional trajectory prediction method and apparatus for multiple waypoint arrival time constraints according to embodiments of this application, with reference to the accompanying drawings. Addressing the issues raised in the background section regarding related technologies, which rarely consider situations where multiple waypoints have arrival time constraints at different flight phases, and where optimization methods cannot effectively resolve situations where the arrival time constraints of multiple input waypoints cannot be simultaneously met, and where solving optimization problems typically requires long computation times, this application provides a four-dimensional trajectory prediction method for multiple waypoint arrival time constraints. In this method, when setting RTA constraints at multiple points along the route, a contracted time window is calculated, and the arrival time constraints of waypoints that can be simultaneously met are retained according to the input priority. This generates a trajectory that satisfies the arrival time constraints of waypoints, enabling the handling of situations where multiple waypoints have arrival time constraints, offering greater applicability and faster processing speed. This solves the problems of related technologies, such as rarely considering situations where multiple waypoints have arrival time constraints at different flight phases, the inability of optimization methods to effectively resolve situations where the arrival time constraints of multiple input waypoints cannot be simultaneously met, and the typically long computation time required to solve optimization problems.

[0034] Specifically, Figure 1 This is a flowchart illustrating a four-dimensional trajectory prediction method for multi-point arrival time constraints provided in an embodiment of this application.

[0035] like Figure 1As shown, the four-dimensional trajectory prediction method for the multi-point arrival time constraint includes the following steps:

[0036] In step S101, the adjustable speed range for different flight phases is determined.

[0037] It is understandable that, in order to reduce the pilot's workload and ensure safety, the RTA adjustment method proposed in this application embodiment can adjust the speed of the aircraft during the flight phase of a smooth configuration.

[0038] Specifically, the adjustable speeds in the embodiments of this application include climb airspeed, climb Mach number, cruise Mach number, descent Mach number, and descent airspeed. The speeds during the initial takeoff acceleration and flap retraction, and during the approach deceleration and flap deployment, do not need to be adjusted.

[0039] Optionally, in one embodiment of this application, determining the adjustable speed range for different flight phases includes: obtaining the maximum climb rate, minimum climb rate, maximum climb Mach number, minimum climb Mach number, maximum cruise Mach number, minimum cruise Mach number, maximum descent Mach number, minimum descent Mach number, maximum descent rate, and minimum descent rate based on aircraft performance limitations and air traffic control limitations.

[0040] In actual implementation, the embodiments of this application can obtain the maximum climb rate V based on aircraft performance limitations and air traffic control restrictions. cl_max Minimum climb rate V cl_min Maximum climb Mach number M cl_max Minimum climb Mach number M cl_min Maximum cruising Mach number M cr_max Minimum cruise Mach number M cr_min Maximum Mach number M de_max Minimum Mach number M de_min Maximum descent speed V de_max Minimum descent speed V de_min .

[0041] In step S102, based on the adjustable speed range of different flight phases, the earliest and latest arrival times at each waypoint are calculated using the fastest and slowest speed schemes for each flight phase, so as to obtain the initial time window for the arrival time of each waypoint.

[0042] For example, in this embodiment of the application, the arrival time of a waypoint on the track predicted using the fastest speed scheme is the fastest arrival time of that waypoint; the arrival time of a waypoint on the track predicted using the slowest speed scheme is the slowest arrival time of that waypoint. The fastest and slowest arrival times of a waypoint represent the range of arrival times to that waypoint in the flight plan, i.e., the initial time window.

[0043] In step S103, the required arrival time limits for waypoints within the initial time window are retained, and the contraction time windows under each retained required arrival time limit are calculated.

[0044] It is understandable that the initial time window of a waypoint describes the limit range of the waypoint's arrival time. Therefore, if the RTA of a waypoint is limited to outside the initial time window, it means that within the speed limit range, it cannot be achieved by adjusting the speed.

[0045] The method for calculating the contraction time window will be explained in detail below.

[0046] Optionally, in one embodiment of this application, after retaining the required arrival time limit for waypoints within the initial time window, the method further includes: returning to air traffic control the constraint of the required arrival time limit on waypoints outside the initial time window.

[0047] For example, embodiments of this application may retain RTA restrictions within the initial time window and return RTA restrictions outside the initial time window to air traffic control or the pilot.

[0048] Optionally, in one embodiment of this application, calculating the contraction time window under each retained required arrival time constraint includes: calculating the contraction of arrival time windows at other waypoints when the required arrival time at one waypoint is satisfied, and determining the contraction time window.

[0049] Understandably, the initial time window represents the maximum arrival time range for each waypoint along the entire route when there are no RTA restrictions. When there is one RTA waypoint on the route, the arrival time windows for other waypoints will shrink if the RTA for that waypoint is met. The shrunken time window represents the earliest and latest arrival times for subsequent waypoints if the aircraft arrives on time at a waypoint with RTA restrictions at a certain speed, then accelerates or decelerates to its maximum or minimum speed.

[0050] Here, a method for calculating at least one contraction time window is described in detail. For example... Figure 3 As shown, the outermost black solid line represents the initial time window calculated from takeoff using the maximum and minimum speeds. The RTAs (Recovery Time Abilities) of waypoints A, B, and C all fall within this time window. When the aircraft in the trajectory prediction meets the RTA limit at point A at a certain speed, it can be accelerated / decelerated to the maximum and minimum speeds to calculate the time windows at subsequent waypoints after the RTA contraction at point A. Figure 3The blue solid line in the figure shows that the RTA constraint at point B is within the contraction time window, indicating that the RTA constraint at point B can be achieved simultaneously with the RTA constraint at point A; while the RTA constraint at point C is outside the contraction time window, indicating that the RTA constraint at point C cannot be achieved simultaneously with the RTA constraint at point A, and the two conflict with each other.

[0051] For each RTA constraint, when determining the subsequent contraction time window, this embodiment of the application can call a trajectory prediction program to calculate the trajectory at the maximum and minimum speeds. When there are many RTA constraints on the route, this process needs to be repeated multiple times, thus increasing the calculation time. After acceleration / deceleration, the subsequent velocity profile is basically the same shape as the velocity profile when calculating the initial time window, and the change in flight time with flight distance is also similar. Therefore, if the impact of brief acceleration and deceleration on time is ignored, the maximum time window can be proportionally shifted to the RTA as the contraction time window after satisfying the RTA. Figure 4 As shown, shifting the maximum speed flight time curve upwards to pass through point A yields the earliest time for each waypoint after satisfying the RTA at point A; shifting the minimum speed flight time curve downwards to pass through point A yields the latest time for the waypoint after satisfying the RTA at point A.

[0052] In step S104, the arrival time limits required for waypoint constraints that can be simultaneously achieved are retained according to the input priority based on the shrinking time window.

[0053] For example, in embodiments of this application, after calculating the contraction time window, the relationship between the input RTAs can be obtained. For a given RTA point, the relationship between other RTA constraints and that RTA point can be categorized into four types. Figure 5 For example, for an RTA constraint point F, point C is an RTA constraint that can be satisfied after it, point D is an RTA constraint that cannot be satisfied after it, point A is an RTA constraint that can be achieved before it, and point B is an RTA constraint that cannot be achieved before it. By analyzing the relationships between multiple RTA points, different RTA constraints can be retained for subsequent speed adjustments based on the importance of the input RTA points to the pilot or air traffic control. The process is as follows: Figure 6 As shown.

[0054] In this embodiment, when retaining RTA points, the input RTA points are first arranged from highest to lowest importance. The first RTA point in the sequence is extracted. Then, based on the relationship between RTA points obtained from the contracted time window, subsequent RTA points in the sequence are sequentially checked to see if they conflict with the first RTA point. If a conflict exists, it means that the RTA point cannot be simultaneously realized with a higher-importance RTA point, and it is removed from the sequence. After processing the first RTA point, the other RTA points in the sequence are processed sequentially. Finally, the sequence will be arranged according to importance, showing the RTA points that can be realized simultaneously.

[0055] In step S105, a track is generated that satisfies the arrival time limit required by the waypoint constraints.

[0056] The method for generating a track that satisfies the arrival time constraints at waypoints will be described in detail below.

[0057] Optionally, generating a track that satisfies the arrival time constraints at waypoints includes: calculating the speed between each pair of waypoints from front to back based on the arrival time constraints at waypoints that can be simultaneously met, in order to generate the track.

[0058] Understandably, determining the speed plan between two RTA points requires first calculating an initial speed plan and initiating iterations. The arrival time of the RTA point under this speed plan is then calculated by calling the trajectory prediction program. The speed plan is further refined based on the error between the arrival time and the RTA, until the RTA constraint is met. Since RTA trajectory prediction does not modify the track before a satisfied RTA point, each call to the trajectory prediction function only needs to calculate the track from the current point to the next RTA point, rather than calculating the entire track, thus reducing computation time.

[0059] Specifically, in this application embodiment, after retaining the simultaneously achievable RTA constraints according to air traffic control priorities, the velocity between two RTA points is calculated from front to back to generate a track that satisfies multi-point RTA constraints. The overall process is as follows: Figure 7 As shown.

[0060] according to Figure 7The process, determining the speed plan between two RTA points from beginning to end, can be divided into six different scenarios based on the different stages the two RTA points are in. Iterative speed calculations can be performed in all of these scenarios, with different methods for determining the initial speed and updating the speed in each iteration for each scenario. Specific scenarios can include: from one cruise segment RTA point to the next cruise segment RTA point; from one climb segment RTA point to the next climb segment RTA point; from one descent segment RTA point to the next descent segment RTA point; from one climb segment RTA point to the next cruise segment RTA point; from one cruise segment RTA point to the next descent segment RTA point; and from one climb segment RTA point to the next descent segment RTA point.

[0061] Combination Figures 2 to 9 As shown, an embodiment is used to illustrate in detail the working principle of the four-dimensional trajectory prediction method for multi-point arrival time constraints of this application.

[0062] like Figure 2 As shown, the four-dimensional trajectory prediction method for multi-point arrival time constraints in this application embodiment specifically includes the following steps:

[0063] Step S201: Determine the speed range for different flight phases.

[0064] To reduce the pilot's workload and ensure safety, the RTA adjustment method proposed in this application only adjusts the aircraft's speed during the flight phase in a smooth configuration. Therefore, the adjustable speeds include climb airspeed, climb Mach number, cruise Mach number, descent Mach number, and descent airspeed. The speeds during the initial takeoff acceleration and flap retraction, and during the approach deceleration and flap deployment, are not adjusted.

[0065] In actual implementation, the embodiments of this application can obtain the maximum climb rate V based on aircraft performance limitations and air traffic control restrictions. cl_max Minimum climb rate V cl_min Maximum climb Mach number M cl_max Minimum climb Mach number M cl_min Maximum cruising Mach number M cr_max Minimum cruise Mach number M cr_min Maximum Mach number M de_max Minimum Mach number M de_min Maximum descent speed V de_max Minimum descent speed V de_min .

[0066] Step S202: Calculate the arrival time window of the waypoint using the maximum and minimum speeds.

[0067] For example, embodiments of this application can invoke the trajectory prediction function of the flight management system to predict the flight trajectory of the entire process when flying at the fastest speed or the minimum speed.

[0068] In this embodiment, the arrival time of a waypoint on the track predicted using the fastest speed scheme is the fastest arrival time of that waypoint; the arrival time of a waypoint on the track predicted using the slowest speed scheme is the slowest arrival time of that waypoint. The fastest and slowest arrival times of a waypoint represent the range of arrival times to that waypoint in the flight plan, i.e., the initial time window.

[0069] Step S203: Retain the RTA limit point within the initial time window.

[0070] Specifically, embodiments of this application can retain RTA limits within the initial time window and return RTA limits outside the initial time window to air traffic control or the pilot. As described in step S202, the initial time window of a waypoint describes the limit range of the waypoint's arrival time. Therefore, if the RTA limit of a waypoint is outside the initial time window, it means that within the speed limit range obtained in step S201, it cannot be achieved by adjusting the speed.

[0071] Step S204: Calculate the time window for contraction after each RTA is satisfied.

[0072] Understandably, the initial time window represents the maximum arrival time range for each waypoint along the entire route when there are no RTA restrictions. When there is one RTA waypoint on the route, the arrival time windows for other waypoints will shrink if the RTA at that waypoint is met. The shrunken time window represents the earliest and latest arrival times for subsequent waypoints if the aircraft arrives on time at a waypoint with RTA restrictions at a certain speed, then accelerates or decelerates to its maximum or minimum speed. Figure 3 As shown, the outermost black solid line represents the initial time window calculated from takeoff using the maximum and minimum speeds. The RTAs (Recovery Time Abilities) for waypoints A, B, and C all fall within this time window. When the aircraft in the trajectory prediction meets the RTA limit at point A at a certain speed, it can be accelerated / decelerated to the maximum and minimum speeds to calculate the time windows for subsequent waypoints after the RTA at point A has contracted. Figure 3 The blue solid line in the figure shows that the RTA constraint at point B is within the contraction time window, indicating that the RTA constraint at point B can be achieved simultaneously with the RTA constraint at point A; while the RTA constraint at point C is outside the contraction time window, indicating that the RTA constraint at point C cannot be achieved simultaneously with the RTA constraint at point A, and the two conflict with each other.

[0073] Furthermore, for each RTA constraint, when determining the subsequent contraction time window, this embodiment of the application can call a trajectory prediction program to calculate the trajectory at the maximum and minimum speeds. When there are many RTA constraints on the route, this process needs to be repeated multiple times, thereby increasing the calculation time. After acceleration / deceleration, the subsequent velocity profile is basically the same shape as the velocity profile when calculating the initial time window, and the change law of flight time with flight distance is also similar. Therefore, if the impact of brief acceleration and deceleration on time is ignored, the maximum time window can be proportionally shifted to the RTA as the contraction time window after satisfying the RTA. Figure 4 As shown, shifting the maximum speed flight time curve upwards to pass through point A yields the earliest time for each waypoint after satisfying the RTA at point A; shifting the minimum speed flight time curve downwards to pass through point A yields the latest time for the waypoint after satisfying the RTA at point A.

[0074] This simplified method inevitably contains some errors compared to methods that estimate arrival times of subsequent waypoints through simulation calculations. These errors mainly stem from the following four points:

[0075] (1) The acceleration and deceleration process after point A was ignored;

[0076] (2) The flight pattern before point A is not considered. During the climb or descent phase, different flight patterns will result in different altitudes to point A. Due to the different winds at different altitudes and the different vacuum speeds corresponding to the indicated air speeds at different altitudes, this simplification method will also introduce errors.

[0077] (3) The different turning radii at different speeds cause errors due to changes in horizontal distance;

[0078] (4) The mass of the aircraft will vary depending on the speed scheme used.

[0079] These errors affect the accuracy of the time window boundaries calculated by the simplified method. Since the time window is narrower for points closer to point A, this effect is greater for points closer to A. Because the simplified method calculates time windows with some error at the boundaries, RTAs outside the time window but close to the boundaries might be achievable through some speed adjustment method. However, the speed adjustment strategy for such boundary-near RTAs may be critical to aircraft performance and place high demands on aircraft control; therefore, this application does not study the satisfaction strategy for such RTAs. Similarly, due to the existence of errors, RTAs within the time window but close to the boundaries, although temporarily considered achievable, may not be achievable in subsequent iterative speed adjustment schemes. Therefore, the time window calculated here serves as a reference for whether the RTA can be satisfied and for speed adjustment; the retained RTAs are not the final achievable RTAs. The subsequent speed adjustment module will verify whether these retained RTAs can be satisfied through trajectory prediction simulation and obtain the corresponding speed scheme; for RTAs that cannot be achieved through simulation, the speed adjustment module will output the trajectory closest to the RTA limit of that point.

[0080] Step S205: Retain the RTA points that need to be satisfied based on the relationship between RTAs.

[0081] Specifically, in this embodiment, when retaining RTA points, the input RTA points are first arranged from highest to lowest importance. The first RTA point in the sequence is extracted. Then, based on the relationship between RTA points obtained from the contracted time window, subsequent RTA points in the sequence are sequentially checked to see if they conflict with the first RTA point. If a conflict exists, it means that the RTA point cannot be simultaneously realized with a higher-importance RTA point, and it is removed from the sequence. After processing the first RTA point, the other RTA points in the sequence are processed sequentially. Finally, the sequence will be arranged according to importance, listing the RTA points that can be realized simultaneously.

[0082] Step S206: Calculate the velocity between every two RTA points from front to back.

[0083] Specifically, after preserving the simultaneously achievable RTA constraints according to air traffic control priorities, the embodiments of this application can calculate the velocity between two RTA points from front to back to generate a track that satisfies multi-point RTA constraints. The overall process is as follows: Figure 7 As shown.

[0084] When determining the speed plan between two RTA points, this embodiment of the application can first calculate an initial speed plan and start iterations. The arrival time of the RTA point under this speed plan is calculated by calling the trajectory prediction program. The speed plan is then further revised based on the error between the arrival time and the RTA, until the RTA constraint is met. Since RTA trajectory prediction does not modify the track before a satisfied RTA point, each call to the trajectory prediction function only needs to calculate the track between the current point and the next RTA point, not the entire track, thus reducing computation time. The overall process is as follows: Figure 8 As shown.

[0085] according to Figure 7 The process, determining the speed plan between two RTA points from front to back, can be divided into six different scenarios based on the different stages the two RTA points are in. All of these can be adopted. Figure 8 The process iteratively calculates the speed for different scenarios. Figure 8 The methods for determining the initial velocity and updating the velocity in each iteration are different.

[0086] (1) From one cruise segment RTA point to the next cruise segment RTA point;

[0087] (2) From one climb RTA point to the next climb RTA point;

[0088] (3) From one descending segment RTA point to the next descending segment RTA point;

[0089] (4) From one climb RTA point to the next cruise RTA point;

[0090] (5) From one cruise segment RTA point to the next descent segment RTA point;

[0091] (6) From one climb RTA point to the next descent RTA point.

[0092] The following sections will introduce the six forms of speed iteration methods mentioned above.

[0093] S1: From one cruise segment RTA point to the next cruise segment RTA point.

[0094] During cruise, the aircraft maintains a certain Mach number for level flight; the adjustable speed is the cruise Mach number. The initial value for speed iteration is the theoretical ground speed, calculated by dividing the distance difference between two RTA points by the time difference. This can then be converted to the cruise Mach number at the corresponding altitude. However, due to acceleration / deceleration processes and the influence of weather conditions (temperature, wind), the theoretically calculated cruise Mach number may not guarantee on-time passage through the target RTA waypoint. Let the initial speed value be M. c_0 The first iteration can calculate M c_0The expected time of arrival (ETA) at the target RTA waypoint during cruise. c_0 If ETA c_0 If the RTA requirements are not met, a new target cruise speed needs to be calculated for a second iteration.

[0095] Let ETA be the earliest expected arrival time of the contraction time window calculated in step S204. max and ETA min That is, accelerate from the current position to M cr_max And the estimated earliest time to reach the target RTA waypoint (ETA) max and decelerate to M cr_min And the estimated latest time (ETA) to reach the target RTA waypoint. min .

[0096] The arrival time varies with cruise speed in a relatively smooth, continuous process. A linear interpolation method is used to calculate the target cruise speed for the next iteration. The calculation formula is:

[0097]

[0098] The expected arrival time (ETA) calculated in each subsequent iteration c_n If the RTA requirements are not met, the target cruise speed M for the next iteration needs to be calculated based on the time error. c_n+1 A similar linear formula can be used, and the calculation formula is as follows:

[0099]

[0100] ETA c_n For M c_n Estimated arrival time of cruise; ETA c_max M is the estimated arrival time in the current iteration that is faster than RTA and has the smallest time difference. c_max For the corresponding cruising speed; ETA c_min This is the result of the iteration that is slower than RTA and has the smallest time difference in the current iteration, and the corresponding cruising speed is M. c_min The iteration ends when the arrival time meets the required tolerance.

[0101] S2: From one climb RTA point to the next climb RTA point.

[0102] The architecture of the speed iteration method between two RTA points in the climb phase can be referenced from the cruise phase. However, during the climb, the aircraft usually maintains constant indicated airspeed, and the speed that can be adjusted is the climb airspeed.

[0103] Since the climb phase is part of the terminal zone, higher RTA accuracy is required; and because the climb and descent phases are much shorter than the cruise phase, the simulation time required is less, allowing for more iterations to improve accuracy. Therefore, to more accurately calculate the RTA adjustment speed, the program can first calculate the acceleration from the already implemented RTA point to V. cl_max and decelerate to V cl_min And by using the track of the target RTA point, the earliest arrival time (ETA) through the target RTA point is obtained. max And latest arrival time ETA min This is to correct the error of the time window contracted using the simplified method. If the required arrival time of the target waypoint is within the ETA... max -ETA min In addition, it indicates that the RTA limit of the target waypoint cannot be met through simulation calculations, and the extreme time to reach the target waypoint and the corresponding track are returned to air traffic control as a reference for adjusting the RTA limit.

[0104] If the required arrival time at the destination waypoint is within the ETA max -ETA min Within this range, the corresponding climb rate needs to be calculated to achieve the RTA limit. At this point (V cl_min ETA min ) and (V cl_max ETA max These are all precise results from simulation calculations, describing the relationship between the aircraft's climb airspeed and arrival time during the climb phase. Initial values ​​for an iteration can be calculated based on these values.

[0105]

[0106] Calculate the climb rate V at arrival time RTA. c_1 After calculating the initial velocity for the iteration, this is used as the new climb velocity. The trajectory prediction module is then invoked to calculate the acceleration / deceleration from the current waypoint to V. c_1 Then wait for the speedometer to complete the climb phase, and obtain the result using V. c_1 Time of Arrival (ETA) when passing the target waypoint during climb c_1 Since the arrival time and apparent velocity are not linearly related, the arrival time ETA calculated in the first iteration is... c_1 It is usually impossible to meet the RTA requirements and needs to be based on the ETA. c_1 Calculate a new velocity V c_2 The process is iterated. Starting from the second iteration, the velocity update formula becomes:

[0107]

[0108] ETA c_n For Vc_n Estimated arrival time of cruise; ETA c_max V is the estimated arrival time in the current iteration that is faster than RTA and has the smallest time difference. c_max For the corresponding cruising speed; ETA c_min This is the result of the iteration that is slower than RTA and has the smallest time difference in the current iteration, and the corresponding cruising speed is V. c_min .

[0109] S3: From one descending segment RTA point to the next descending segment RTA point.

[0110] During the descent phase, the aircraft flies primarily at indicated airspeed. Therefore, the speed iteration method between the two RTA points during the descent phase is similar to that between the two RTA points during the climb phase, and will not be elaborated further.

[0111] S4: From one climb RTA point to the next cruise RTA point.

[0112] After the RTA trajectory prediction completes the last RTA waypoint of the climb phase, it is necessary to adjust the climb speed and the cruise speed after entering cruise for the first RTA waypoint of the cruise phase. The method designed in this application, when iterating the speed between the climb phase RTA waypoint and the cruise phase RTA waypoint, first considers adjusting the cruise phase speed. If adjusting the cruise phase speed alone cannot meet the RTA requirements, then it further considers simultaneously adjusting the climb phase speed after the climb phase RTA waypoint.

[0113] When adjusting the cruise speed separately, this embodiment of the application requires maintaining the current climb speed to complete the climb segment: if the airspeed has not yet reached the previously input climb speed (such as the economic climb speed), then accelerate to the original climb speed and complete the climb segment according to the original climb speed plan; if the airspeed has exceeded the original climb speed when completing the last RTA point of the climb segment, in order to avoid unnecessary fuel waste, then do not decelerate and maintain the current speed to complete the climb segment.

[0114] After completing the climb segment, the climb peak can be regarded as a completed cruise segment RTA waypoint (the RTA limit is the arrival time of the current climb peak). The speed between the climb peak and the target cruise segment RTA point can be adjusted using the S1 method.

[0115] If a speed that satisfies the RTA cannot be calculated, it means that adjusting the cruise speed alone cannot achieve the target RTA, and the climb speed needs to be adjusted simultaneously. If a speed that satisfies the RTA is calculated iteratively, its value can be further checked to see if it is close to the maximum or minimum speed. If the calculated cruise speed is close to the limit speed, it means the aircraft needs to make a significant speed adjustment and cruise at a relatively high / low speed to meet the RTA constraint. If the aircraft encounters unexpected situations during the cruise phase, the RTA constraint may not be met, therefore the speed adjustment scheme may not be safe enough. The robustness of the speed adjustment scheme can be improved by adjusting the climb speed. In this embodiment, if the difference between the cruise speed and the maximum or minimum speed is greater than one-third of the cruise speed range, it is considered close to the maximum or minimum speed.

[0116] When adjusting the cruise speed alone is insufficient to achieve RTA, it's necessary to consider simultaneously adjusting the climb and cruise speeds. The adjustable variables in this case are the climb airspeed and the cruise Mach number (to reduce pilot complexity, the climb Mach number can be set equal to the cruise Mach number). To maximize the use of the adjustable speed ranges in both the climb and cruise segments, ensuring that both calculated speeds are as far from the speed limits as possible and as close as possible to the original user-input speed plan (e.g., economic speed), the following approach can be adopted: Figure 9 The speed adjustment direction is shown. The initial iteration value is taken from the original speed plan input by the user (V). cal_plan M cr_plan When acceleration is needed during iteration, the direction of the speed change is from the initial value direction to the fastest speed (V). cl_max M cr_max When deceleration is required, the direction of speed adjustment is from the initial value direction to the slowest speed (V). cl_min M cr_min ).

[0117] After a fixed direction of speed change, the method for iterating two speeds is the same as iterating one speed: in each iteration, first calculate the arrival time at the current speed. If the requirement is not met, calculate the climb speed and cruise speed for the next iteration according to the linear formulas in S1 and S2, until the arrival time meets the RTA requirement.

[0118] Since the speed update is a linear formula, the change in the climbing speed V during each iteration c_n+1 -V c_n The speed range V of the iterative reference c_max -V c_min The ratio and the change in cruise Mach number M c_n+1 -M c_n The speed range M of the iterative referencec_max -M c_min The ratios are all (RTA-ETA) c_n ) / (ETA c_max -ETA c_min Therefore, if the climb rate and cruise Mach number are updated using the linear formula described above in each iteration, the two speeds will remain constant. Figure 7 A straight line indicating acceleration or deceleration shows that the climb rate and cruise Mach number are approaching their respective limits at the same rate. Therefore, the climb rate and cruise Mach number calculated using this method provide a more balanced utilization of aircraft performance, avoiding a situation where one climb rate or cruise speed is close to its limit while the other still has considerable room for adjustment in the final adjustment result.

[0119] S5: From one cruise segment RTA point to the next descent segment RTA point.

[0120] Specifically, in this embodiment, after processing the last RTA waypoint of the cruise segment and before the first descent RTA waypoint, two speeds can be adjusted: the subsequent cruise speed and the descent speed before the target RTA waypoint. To maintain the preset speed mode of cruise (such as economy mode) as much as possible, when handling this situation, the first consideration is to adjust only the indicated airspeed during the descent segment to achieve RTA. If this is not possible, then the cruise segment speed is adjusted, similar to the approach used when handling the transition from the last climb RTA point to the first cruise RTA point.

[0121] When adjusting only the descent Mach number, after the RTA point of the last cruise segment, it is necessary to first adjust back to the pilot's preset cruise speed (such as economic speed), then predict the trajectory to the descent peak, and take the descent peak as an achieved descent segment RTA point. The speed between the descent peak and the target descent segment RTA point is adjusted using the S3 method.

[0122] If adjusting the descent speed alone is insufficient to achieve RTA, further consideration will be given to simultaneously adjusting both cruise and descent speeds. The variables to be adjusted are the descent speed and the cruise Mach number (setting the descent Mach number equal to the cruise Mach number). The method for iteratively adjusting both speeds is the same as in S4, but the direction of acceleration adjustment is from the original speed plan (V... de_plan M cr_plan ) points to the fastest speed (V) de_max M cr_max The direction of the deceleration adjustment is from the original speed plan (V). de_plan M cr_plan ) points to the slowest speed (V) de_min M cr_min The choice of initial values ​​and the speed update in each iteration are the same as in S4, so they will not be repeated here.

[0123] S6: From one climb RTA point to the next descent RTA point.

[0124] When the last RTA point of the climb phase is completed, if there is no RTA limit for the entire cruise phase, the next RTA limit will be in the descent phase. At this point, the adjustable speeds include climb, cruise, and descent speeds.

[0125] In this situation, to avoid impacting the arrival time across the entire flight path, we first consider adjusting only the descent speed to achieve the RTA limit. This requires completing the climb and cruise phases according to the original speed plan and reaching the descent peak. Treating the descent peak as a completed descent RTA point, we iteratively calculate the descent speed that can achieve the RTA using the S3 method. If adjusting only the descent speed cannot achieve the RTA limit, then we further consider adjusting the cruise speed.

[0126] When adjusting the cruise speed, the current climb peak can be regarded as the RTA point where the cruise segment has been completed. Using the S5 method, the cruise speed and descent speed that can satisfy the RTA can be calculated.

[0127] If adjusting the cruise and descent speeds still fails to meet the RTA limit, then further consideration should be given to adjusting the final speed of the climb. In this case, the climb speed, cruise Mach number, and descent speed can be adjusted simultaneously (setting the climb Mach number and descent Mach number equal to the cruise Mach number), using the same framework as when iteratively calculating the two speeds. All three speeds are iteratively adjusted simultaneously, with initial values ​​starting from (V... cl_plan V de_plan M cr_plan To begin, if acceleration is needed, move towards (V). cl_max V de_max M cr_max Adjust (V) if deceleration is required. cl_min V de_min M cr_min )adjust.

[0128] Apart from the realization of the first RTA point after takeoff, the problem of generating a track between two RTA limit points sequentially starting from the first RTA point can be decomposed into a combination of the above six cases.

[0129] The realization of the first RTA waypoint after takeoff can also be converted into one of the six cases mentioned above. In this case, it is necessary to consider the cases of the first RTA waypoint in the climb phase, cruise phase, and descent phase respectively.

[0130] Since the method designed in this application embodiment does not adjust the speed during the initial climb phase after takeoff, the first position where speed adjustment is allowed is the position where the plane becomes smooth. For the RTA speed regulation problem, the track before this point will not change, and the arrival time and speed at this point will also not change. Therefore, the problem of calculating the speed of the first RTA waypoint after takeoff can be transformed into a speed regulation problem between the point where the plane becomes smooth and the first RTA waypoint. If the point where the plane becomes smooth with a fixed arrival time and speed is considered as a completed RTA point, the problem can be transformed into a speed optimization problem between two RTA points. If the first RTA waypoint is in the climb phase, the process can be referenced from the climb phase RTA point (the point of transition to a smooth configuration) to the next climb phase RTA (the first RTA waypoint); if the first RTA waypoint is in the cruise phase, the process can be referenced from the climb phase RTA point (the point of transition to a smooth configuration) to the next cruise phase RTA (the first RTA waypoint); if the first RTA waypoint is in the descent phase, the process can be referenced from the climb phase RTA point (the point of transition to a smooth configuration) to the next descent phase RTA (the first RTA waypoint).

[0131] S7: Predict the trajectory from the start of the last RTA point to the end point.

[0132] After completing all RTA points along the route using the method described above, it is still necessary to predict the trajectory from the last RTA point to landing. This problem is unrelated to the RTA; it is only necessary to predict the trajectory from the current last RTA point to the destination. It is important to note that since the subsequent trajectory is no longer subject to RTA restrictions, the speed for each flight phase should be the speed from the original flight plan. For example, if the last RTA point is in the cruise phase, the speed needs to be adjusted back to the original cruise speed after completing the RTA point. However, from an operational and fuel perspective, there are two special cases: If the last RTA point is in the climb phase, and the indicated climb airspeed after completing the RTA point is greater than the original indicated climb airspeed or the current Mach number is greater than the planned climb Mach number, then the speed should not be adjusted back to the original speed plan; the current indicated airspeed or Mach number should be maintained for the trajectory after completion without deceleration. If the last RTA point is in the descent phase, and the indicated descent airspeed after completing the RTA point is lower than the planned descent airspeed, then it is not necessary to accelerate back to the descent airspeed.

[0133] The four-dimensional trajectory prediction method for multiple waypoint arrival time constraints proposed in this application can calculate a contracted time window when setting RTA constraints at multiple points along the way, and retain the waypoints with simultaneously achievable arrival time constraints according to the input priority, thereby generating a trajectory that satisfies the waypoint constraints. This method can handle situations with multiple waypoints having arrival time constraints, offering greater applicability and faster processing speed. It addresses the problems in related technologies, such as the lack of consideration for situations with multiple waypoints having arrival time constraints at different flight phases, the inability of optimized methods to effectively solve situations where the arrival time constraints of multiple waypoints cannot be achieved simultaneously, and the typically long computation time required to solve optimization problems.

[0134] Next, referring to the accompanying drawings, a four-dimensional trajectory prediction device for multiple point arrival time constraints proposed according to an embodiment of this application is described.

[0135] Figure 10 This is a block diagram of a four-dimensional trajectory prediction device for multi-point arrival time constraints according to an embodiment of this application.

[0136] like Figure 10 As shown, the four-dimensional trajectory prediction device 10 for multi-point arrival time constraints includes: a determination module 100, an acquisition module 200, a calculation module 300, a retention module 400, and a generation module 500.

[0137] The determining module 100 is used to determine the adjustable speed range for different flight phases.

[0138] The acquisition module 200 is used to calculate the earliest and latest arrival times at each waypoint based on the speed adjustable range of different flight phases, using the fastest and slowest speed schemes for each flight phase, so as to obtain the initial time window for the arrival time of each waypoint.

[0139] The calculation module 300 is used to retain the required arrival time limits of waypoints within the initial time window and to calculate the shrinkage time window under each retained required arrival time limit.

[0140] The retention module 400 is used to retain the arrival time limits required for waypoint constraints that can be simultaneously achieved according to the input priority within the contraction time window.

[0141] The generation module 500 is used to generate a track that meets the arrival time limit required by the constraints on waypoints.

[0142] Optionally, in one embodiment of this application, the determining module 100 includes: an acquisition unit.

[0143] The acquisition unit is used to acquire the maximum climb rate, minimum climb rate, maximum climb Mach number, minimum climb Mach number, maximum cruise Mach number, minimum cruise Mach number, maximum descent Mach number, minimum descent Mach number, maximum descent airspeed, and minimum descent airspeed based on aircraft performance limitations and air traffic control limitations.

[0144] Optionally, in one embodiment of this application, the four-dimensional trajectory prediction device 10 with multiple point arrival time constraints further includes a return module.

[0145] The return module is used to return to air traffic control the required arrival time limit for waypoints outside the initial time window.

[0146] Optionally, in one embodiment of this application, the calculation module 300 is further configured to calculate the situation where the arrival time window at other waypoints shrinks when the required arrival time at a waypoint is satisfied, and to determine the shrinking time window.

[0147] Optionally, in one embodiment of this application, the generation module 500 includes a generation unit.

[0148] The generation unit is used to calculate the speed between the arrival time points of every two waypoint constraints from front to back, based on the arrival time limits required for constraints that can be achieved simultaneously, in order to generate a track.

[0149] It should be noted that the explanation of the above-described embodiment of the four-dimensional trajectory prediction method with time constraints for multiple points also applies to the four-dimensional trajectory prediction device with time constraints for multiple points in this embodiment, and will not be repeated here.

[0150] The four-dimensional trajectory prediction device for multiple waypoint arrival time constraints proposed in this application can calculate a contracted time window when setting RTA constraints at multiple points along the way, and retain the waypoint constraints that can be simultaneously met according to the input priority, thereby generating a trajectory that satisfies the waypoint constraints. This device can handle situations with multiple waypoints having arrival time constraints, offering greater applicability and faster processing speed. It solves the problems in related technologies, such as the lack of consideration for situations with multiple waypoints having arrival time constraints at different flight phases, the inability of optimization methods to effectively address situations where the arrival time constraints of multiple waypoints cannot be met simultaneously, and the typically long computation time required to solve optimization problems.

[0151] Figure 11 A schematic diagram of the structure of an electronic device provided in an embodiment of this application. The electronic device may include:

[0152] The memory 1101, the processor 1102, and the computer program stored on the memory 1101 and executable on the processor 1102.

[0153] When the processor 1102 executes the program, it implements the four-dimensional trajectory prediction method for the multi-point arrival time limit provided in the above embodiments.

[0154] Furthermore, electronic devices also include:

[0155] Communication interface 1103 is used for communication between memory 1101 and processor 1102.

[0156] The memory 1101 is used to store computer programs that can run on the processor 1102.

[0157] The memory 1101 may include high-speed RAM memory, and may also include non-volatile memory, such as at least one disk storage device.

[0158] If the memory 1101, processor 1102, and communication interface 1103 are implemented independently, then the communication interface 1103, memory 1101, and processor 1102 can be interconnected via a bus to complete communication between them. The bus can be an Industry Standard Architecture (ISA) bus, a Peripheral Component Interconnect (PCI) bus, or an Extended Industry Standard Architecture (EISA) bus, etc. Buses can be divided into address buses, data buses, control buses, etc. For ease of representation, Figure 11 The bus is represented by a single thick line, but this does not mean that there is only one bus or one type of bus.

[0159] Optionally, in a specific implementation, if the memory 1101, processor 1102, and communication interface 1103 are integrated on a single chip, then the memory 1101, processor 1102, and communication interface 1103 can communicate with each other through an internal interface.

[0160] The processor 1102 may be a central processing unit (CPU), an application specific integrated circuit (ASIC), or one or more integrated circuits configured to implement the embodiments of this application.

[0161] This application also provides a computer-readable storage medium storing a computer program that, when executed by a processor, implements the above-described four-dimensional trajectory prediction method for multi-point arrival time constraints.

[0162] In the description of this specification, the references to terms such as "one embodiment," "some embodiments," "example," "specific example," or "some examples," etc., indicate that a specific feature, structure, material, or characteristic described in connection with that embodiment or example is included in at least one embodiment or example of this application. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples. Moreover, without contradiction, those skilled in the art can combine and integrate the different embodiments or examples described in this specification, as well as the features of different embodiments or examples.

[0163] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include at least one of that feature. In the description of this application, "N" means at least two, such as two, three, etc., unless otherwise explicitly specified.

[0164] Any process or method described in the flowchart or otherwise herein can be understood as representing a module, segment, or portion of code comprising one or N executable instructions for implementing custom logic functions or processes, and the scope of the preferred embodiments of this application includes additional implementations in which functions may be performed not in the order shown or discussed, including substantially simultaneously or in reverse order depending on the functions involved, as should be understood by those skilled in the art to which embodiments of this application pertain.

[0165] The logic and / or steps represented in the flowchart or otherwise described herein, for example, can be considered as a sequenced list of executable instructions for implementing logical functions, and can be embodied in any computer-readable medium for use by, or in conjunction with, an instruction execution system, apparatus, or device (such as a computer-based system, a processor-included system, or other system that can fetch and execute instructions from, an instruction execution system, apparatus, or device). For the purposes of this specification, "computer-readable medium" can be any means that can contain, store, communicate, propagate, or transmit programs for use by, or in conjunction with, an instruction execution system, apparatus, or device. More specific examples (a non-exhaustive list) of computer-readable media include: an electrical connection having one or more wires (electronic device), a portable computer disk drive (magnetic device), random access memory (RAM), read-only memory (ROM), erasable and editable read-only memory (EPROM or flash memory), fiber optic devices, and portable optical disc read-only memory (CDROM). Alternatively, the computer-readable medium may be paper or other suitable media on which the program can be printed, since the program can be obtained electronically by optically scanning the paper or other medium, followed by editing, interpreting, or otherwise processing as necessary, and then stored in a computer memory.

[0166] It should be understood that the various parts of this application can be implemented using hardware, software, firmware, or a combination thereof. In the above embodiments, the N steps or methods can be implemented using software or firmware stored in memory and executed by a suitable instruction execution system. If implemented in hardware, as in another embodiment, it can be implemented using any one or a combination of the following techniques known in the art: discrete logic circuits having logic gates for implementing logical functions on data signals, application-specific integrated circuits (ASICs) having suitable combinational logic gates, programmable gate arrays (PGAs), field-programmable gate arrays (FPGAs), etc.

[0167] Those skilled in the art will understand that all or part of the steps of the methods in the above embodiments can be implemented by a program instructing related hardware. The program can be stored in a computer-readable storage medium, and when executed, the program includes one or a combination of the steps of the method embodiments.

[0168] Furthermore, the functional units in the various embodiments of this application can be integrated into a processing module, or each unit can exist physically separately, or two or more units can be integrated into a module. The integrated module can be implemented in hardware or as a software functional module. If the integrated module is implemented as a software functional module and sold or used as an independent product, it can also be stored in a computer-readable storage medium.

[0169] The storage medium mentioned above can be a read-only memory, a disk, or an optical disk, etc. Although embodiments of this application have been shown and described above, it is understood that the above embodiments are exemplary and should not be construed as limiting this application. Those skilled in the art can make changes, modifications, substitutions, and variations to the above embodiments within the scope of this application.

Claims

1. A four-dimensional trajectory prediction method with multiple point arrival time constraints, characterized in that, Includes the following steps: Determine the adjustable speed range for different flight phases; Based on the adjustable speed range of the different flight phases, the earliest and latest arrival times at each waypoint are calculated using the fastest and slowest speed schemes for each flight phase, so as to obtain the initial time window for the arrival time at each waypoint. The required arrival time constraints of waypoints within the initial time window are retained, and the contraction time windows under each retained required arrival time constraint are calculated, including: calculating the contraction of arrival time windows at other waypoints when the required arrival time constraint at one waypoint is met, and determining the contraction time window, wherein the contraction time window is the earliest and latest arrival time at subsequent waypoints when the aircraft arrives on time at a waypoint with a required arrival time constraint at a certain speed, then accelerates or decelerates to the maximum or minimum speed. According to the shrinking time window, the required arrival time limits for waypoint constraints that can be simultaneously achieved are retained based on the input priority. After calculating the shrinking time window, the relationship between each input required arrival time is obtained. Specifically, for a given required arrival time, the relationship between other required arrival time constraints and that required arrival time point is categorized as: those that can be satisfied after it, those that cannot be satisfied after it, those that can be achieved before it, and those that cannot be achieved before it. When retaining required arrival time points, the input required arrival time points are first arranged from highest to lowest importance. The first required arrival time point in the sequence is extracted. Then, based on the relationship between the required arrival time points obtained from the shrinking time window, subsequent required arrival time points in the sequence are sequentially checked against the first required arrival time point. If a conflict occurs, it indicates that the required arrival time point cannot be simultaneously achieved with a higher-importance required arrival time point, and it is removed from the sequence. After processing the first required arrival time point, the other required arrival time points in the sequence are processed sequentially. Finally, the sequence will be arranged according to importance, with required arrival time points that can be simultaneously achieved arranged accordingly. Generate a track that satisfies the arrival time constraints at waypoints.

2. The method according to claim 1, characterized in that, The determination of the adjustable speed range for different flight phases includes: Based on aircraft performance limitations and air traffic control restrictions, obtain the maximum climb rate, minimum climb rate, maximum climb Mach number, minimum climb Mach number, maximum cruise Mach number, minimum cruise Mach number, maximum descent Mach number, minimum descent Mach number, maximum descent airspeed, and minimum descent airspeed.

3. The method according to claim 1, characterized in that, After retaining the required arrival time limits for waypoints within the initial time window, the following is also included: The air traffic controller returns to the waypoint outside the initial time window to constrain the required arrival time limit.

4. The method according to claim 1, characterized in that, The generation of a track that satisfies the arrival time constraints at waypoints includes: Based on the arrival time constraints required for the simultaneous waypoint constraints, the speed between the arrival time constraints of every two waypoints is calculated from front to back to generate the trajectory.

5. A four-dimensional trajectory prediction device with multi-point arrival time constraints, characterized in that, The apparatus comprising the method as described in any one of claims 1-4, wherein the apparatus includes: The determination module is used to determine the adjustable speed range for different flight phases; The acquisition module is used to calculate the earliest and latest arrival times at each waypoint based on the adjustable speed range of the different flight phases, using the fastest and slowest speed schemes for each flight phase, so as to obtain the initial time window for the arrival time of each waypoint. The calculation module is used to retain the required arrival time limits for waypoints within the initial time window and to calculate the contraction time window for each retained required arrival time limit; The retention module is used to retain the arrival time limits required for waypoint constraints that can be simultaneously achieved according to the input priority within the contraction time window; and The generation module is used to generate tracks that meet the arrival time constraints required by waypoints.

6. The apparatus according to claim 5, characterized in that, The determining module is further used to obtain the maximum climb rate, minimum climb rate, maximum climb Mach number, minimum climb Mach number, maximum cruise Mach number, minimum cruise Mach number, maximum descent Mach number, minimum descent Mach number, maximum descent rate, and minimum descent rate based on aircraft performance limitations and air traffic control limitations.

7. The apparatus according to claim 5, characterized in that, Also includes: The return module is used to return to air traffic control the required arrival time limit for waypoints outside the initial time window.

8. An electronic device, characterized in that, include: The memory, the processor, and the computer program stored in the memory and executable on the processor, the processor executing the program to implement the four-dimensional trajectory prediction method for multi-point arrival time constraints as described in any one of claims 1-4.

9. A computer-readable storage medium having a computer program stored thereon, characterized in that, The program is executed by the processor to implement the four-dimensional trajectory prediction method for multi-point arrival time constraints as described in any one of claims 1-4.

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