Compound wing unmanned aerial vehicle formation cooperative control method, device, equipment and medium

Abstract

The application discloses a composite wing unmanned aerial vehicle formation cooperative control method and device, equipment and medium, relates to the composite wing unmanned aerial vehicle technical field, and includes: receiving the state information and formation switching instruction broadcast by the long machine; determining the offset vector relative to the long machine according to the formation switching instruction corresponding formation geometry configuration; converting the offset vector into a theoretical target point according to the state information; according to the judgment result that the theoretical target point is located in the preset forward flyable sector, gradually iteratively extrapolate and update the long machine current position and the long machine ground heading angle in the state information, and obtain the target update point; obtain the feedforward wind speed component, calculate the target airspeed according to the state information, the longitudinal error of the target update point projected along the heading angle of the long machine and the feedforward wind speed component; when the longitudinal error is greater than the negative preset deceleration margin, the target airspeed is set to the preset minimum cruising airspeed, and the target airspeed is limited in the preset airspeed range, so as to form the airspeed setting value of the wingman during the formation switching period.

Description

Technical Field

[0001] This application relates to the field of compound-wing unmanned aerial vehicle (UAV) technology, and in particular to methods, devices, equipment and media for coordinated control of compound-wing UAV formations. Background Technology

[0002] Multi-UAV formation collaborative control is widely used in scenarios such as formation performance, collaborative surveying and mapping, collaborative inspection and emergency search and rescue. Among them, compound wing UAV formations often need to perform formation switching tasks in fixed-wing cruise mode, so they need to have the ability to locate target points in the transient process.

[0003] Some schemes that directly generate target points based on the lead aircraft's current state do not fully consider the changes in target points caused by the lead aircraft's continuous forward flight. The generated target point may fall to the side or rear of the wingman, requiring the fixed-wing wingman to make a significant turn. When the wingman is ahead, it is also necessary to consider the deceleration requirements and minimum safe airspeed limits. Therefore, how to improve the target point orientation during formation changes to maintain the same longitudinal position has become an urgent problem to be solved. Summary of the Invention

[0004] The main objective of this application is to provide a method, apparatus, device, and medium for coordinated control of a compound-wing unmanned aerial vehicle (UAV) formation, aiming to solve the technical problem of how to improve the orientation of the target point during formation switching in order to maintain the same longitudinal position.

[0005] To achieve the above objectives, this application proposes a cooperative control method for formation control of a compound-wing unmanned aerial vehicle (UAV), the method comprising: Receive status information and formation switching instructions broadcast by the lead aircraft; Based on the formation geometry configuration corresponding to the formation switching command, determine the offset vector relative to the lead aircraft; Based on the lead aircraft's current position and ground heading angle in the status information, the offset vector is converted into a theoretical target point; Based on the judgment result that the theoretical target point is located in the preset forward flyable sector, the current position of the lead aircraft and the heading angle of the lead aircraft to the ground in the status information are iteratively updated step by step until the preset termination condition is met, and the target update point is obtained. Obtain the feedforward wind speed component, and calculate the target airspeed based on the state information, the longitudinal error of the target update point projected along the heading angle of the lead aircraft, and the feedforward wind speed component. When the longitudinal error is greater than the negative preset deceleration margin, the target airspeed is set to the preset minimum cruise airspeed, and the target airspeed is limited between the preset minimum cruise airspeed and the preset maximum cruise airspeed. Based on the limited target airspeed, the airspeed setting value of the wingman during formation switching is generated.

[0006] In one embodiment, the step of determining the offset vector relative to the lead aircraft based on the formation geometry configuration corresponding to the formation switching command includes: According to the target formation number corresponding to the formation switching command, the corresponding formation geometry configuration is searched from the preset formation parameter library. The formation geometry configuration includes the relative positional relationship of each wingman in the formation. An offset vector relative to the lead aircraft is determined based on the formation geometry, the offset vector including a longitudinal offset component and a lateral offset component.

[0007] In one embodiment, the step of converting the offset vector into a theoretical target point based on the lead aircraft's current position and ground heading angle in the state information includes: Using the current position of the lead aircraft in the status information as a reference, the offset vector is rotated and transformed according to the lead aircraft's heading angle to the ground in the status information to obtain the offset coordinate increment; The offset coordinate increment is superimposed on the current position of the lead aircraft in the status information to obtain the theoretical target point.

[0008] In one embodiment, the step of iteratively updating the lead aircraft's current position and ground heading angle in the state information based on the judgment result that the theoretical target point is located in a preset forward flyable sector, until a preset termination condition is met, to obtain the target update point includes: Obtain the current position, velocity vector, and preset sector half-angle of each wingman; Calculate the normalized inner product of the direction vector from the current position of each wingman to the theoretical target point and the velocity vector; When the normalized inner product is greater than the cosine of the preset sector half-angle, the theoretical target point is determined to be located within the preset forward flyable sector, and the theoretical target point is determined as the target update point. When the normalized inner product is not greater than the cosine of the preset sector half angle, starting from the preset initial prediction duration, the target prediction duration is incremented by the preset step size, and the predicted position and predicted heading of the lead aircraft are iteratively extrapolated based on the current position of the lead aircraft, the lead aircraft's heading angle to the ground, and the target prediction duration to obtain the target update point.

[0009] In one embodiment, the state information further includes the lead aircraft's ground speed and the lead aircraft's heading rate of change; the step of iteratively extrapolating the lead aircraft's predicted position and predicted heading based on the lead aircraft's current position and ground heading angle in the state information and the target prediction time to obtain the target update point includes: Based on the lead aircraft’s current position, lead aircraft’s ground speed, lead aircraft’s ground heading angle, lead aircraft’s heading change rate, and target prediction time, calculate the lead aircraft’s predicted position and the corresponding lead aircraft’s predicted heading. Based on the predicted position and predicted course of the lead aircraft, target candidate points are determined, and the forward flyable sector determination is re-executed for the target candidate points; If the target candidate point passes the forward flyable sector determination, then the target candidate point is used as the target update point; if the target candidate point fails the forward flyable sector determination and the target prediction time is less than the preset time limit, then the target prediction time is increased by the preset step size and the iteration continues; if the target candidate point fails the forward flyable sector determination and the target prediction time reaches the preset time limit, then the iteration stops, and the original theoretical target point calculated based on the current position and current heading angle of the lead aircraft is used as the target update point.

[0010] In one embodiment, the step of calculating the target airspeed based on the state information, the longitudinal error of the target update point projected along the heading angle of the lead aircraft, and the feedforward wind speed component includes: Obtain the environmental wind speed vector, project the environmental wind speed vector onto the lead aircraft's ground-to-ground heading, and obtain the feedforward wind speed component; The difference vector relative to the target update point is projected onto the lead aircraft's ground heading to obtain the longitudinal error, wherein a positive longitudinal error indicates that the wingman is ahead of the target update point, and a negative longitudinal error indicates that the wingman is behind the target update point; The target airspeed is calculated based on the lead aircraft's ground speed, the feedforward wind speed component, the preset longitudinal proportional gain, and the longitudinal error in the status information. When the longitudinal error is greater than the negative preset deceleration margin, the target airspeed is set to the preset minimum cruise airspeed; the target airspeed is limited between the preset minimum cruise airspeed and the preset maximum cruise airspeed.

[0011] In one embodiment, the compound-wing UAV formation cooperative control method further includes: Get the preset backoff distance; Based on the lead aircraft's ground heading angle, the target update point, and the preset backtracking distance in the status information, a virtual previous waypoint is determined in the opposite direction of the lead aircraft's ground heading. The target update point is used as the current waypoint, the virtual previous waypoint is used as the previous waypoint, and guidance input is provided to the fixed-wing position controller in combination with the target airspeed. Guide the wingman to approach the target update point along the lead aircraft's ground heading angle.

[0012] Furthermore, to achieve the above objectives, this application also proposes a compound-wing UAV formation cooperative control device, which includes: The receiving module is used to receive status information and formation switching instructions broadcast by the primary aircraft. The determination module is used to determine the offset vector relative to the lead aircraft based on the formation geometry configuration corresponding to the formation switching instruction; The conversion module is used to convert the offset vector into a theoretical target point based on the current position of the lead aircraft and the lead aircraft's heading angle to the ground in the status information. The update module is used to iteratively update the current position of the lead aircraft and the heading angle of the lead aircraft to the ground in the status information based on the judgment result that the theoretical target point is located in the preset forward flyable sector, until the preset termination condition is met, and the target update point is obtained. The calculation module is used to obtain the feedforward wind speed component and calculate the target airspeed based on the state information, the longitudinal error of the target update point projected along the heading angle of the lead aircraft, and the feedforward wind speed component. The execution module is used to set the target airspeed to a preset minimum cruise airspeed and limit the target airspeed between the preset minimum cruise airspeed and the preset maximum cruise airspeed when the longitudinal error is greater than a negative preset deceleration margin, and to generate the airspeed setting value of the wingman during formation switching based on the limited target airspeed.

[0013] In addition, to achieve the above objectives, this application also proposes a compound-wing UAV formation cooperative control device, the device comprising: a memory, a processor, and a computer program stored in the memory and executable on the processor, the computer program being configured to implement the steps of the compound-wing UAV formation cooperative control method described above.

[0014] In addition, to achieve the above objectives, this application also proposes a storage medium, which is a computer-readable storage medium, on which a computer program is stored, and when the computer program is executed by a processor, it implements the steps of the compound-wing UAV formation cooperative control method described above.

[0015] One or more technical solutions proposed in this application have at least the following technical effects: This application performs forward sector determination on theoretical target points, and extrapolates the lead aircraft position and heading by increasing prediction time when the determination fails, until the target candidate point passes the determination or reaches the upper limit of the prediction time; if the upper limit is reached but the target still fails, the original theoretical target point is used as a fallback, so that the search terminates within a finite number of steps and a definite target point is output. The target airspeed is generated and limited based on the longitudinal error and the wind speed component along the lead aircraft heading, which is beneficial to improving the target point orientation and longitudinal position during formation switching. Attached Figure Description

[0016] The accompanying drawings, which are incorporated in and form part of this specification, illustrate embodiments consistent with this application and, together with the description, serve to explain the principles of this application.

[0017] To more clearly illustrate the technical solutions in the embodiments of this application or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, for those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0018] Figure 1 This is a flowchart illustrating an embodiment of the compound-wing UAV formation cooperative control method of this application. Figure 2 This is a flowchart illustrating Embodiment 2 of the compound-wing UAV formation cooperative control method of this application; Figure 3 This is a schematic diagram illustrating the guidance of the composite-wing UAV formation cooperative control method of this application; Figure 4 This is a schematic diagram of the module structure of the compound-wing UAV formation cooperative control device according to an embodiment of this application; Figure 5 This is a schematic diagram of the equipment structure of the hardware operating environment involved in the compound wing UAV formation cooperative control method in the embodiments of this application.

[0019] The purpose, features, and advantages of this application will be further explained in conjunction with the embodiments and with reference to the accompanying drawings. Detailed Implementation

[0020] It should be understood that the specific embodiments described herein are merely illustrative of the technical solutions of this application and are not intended to limit this application.

[0021] To better understand the technical solution of this application, a detailed description will be provided below in conjunction with the accompanying drawings and specific implementation methods.

[0022] The main solution of this application embodiment is as follows: receiving status information and formation switching instructions broadcast by the lead aircraft; determining the offset vector relative to the lead aircraft based on the formation geometry configuration corresponding to the formation switching instructions; converting the offset vector into a theoretical target point based on the lead aircraft's current position and ground heading angle in the status information; iteratively updating the lead aircraft's current position and ground heading angle in the status information based on the judgment result that the theoretical target point is located in a preset forward flyable sector, until a preset termination condition is met, and obtaining a target update point; acquiring the feedforward wind speed component, calculating the target airspeed based on the status information, the longitudinal error of the target update point projected along the lead aircraft's heading angle, and the feedforward wind speed component; when the longitudinal error is greater than a negative preset deceleration margin, setting the target airspeed to a preset minimum cruise airspeed, and limiting the target airspeed between the preset minimum cruise airspeed and the preset maximum cruise airspeed, generating the wingman's airspeed setting value during formation switching based on the limited target airspeed.

[0023] In this embodiment, for ease of description, the following description uses a compound-wing UAV formation cooperative control device as the execution subject.

[0024] Because some schemes that generate target points directly based on the current state of the lead aircraft may not fully consider the changes in target points caused by the lead aircraft's continuous forward flight, the generated target points may fall to the side and rear of the wingman. When the wingman is ahead, it is also necessary to take into account the longitudinal deceleration requirements and the minimum safe airspeed limit.

[0025] This application provides a solution that performs forward sector determination on theoretical target points and extrapolates the lead aircraft position and heading by incrementally increasing prediction time when the determination fails, until the target candidate point passes the determination or reaches the upper limit of the prediction time; if it still fails when the upper limit is reached, the original theoretical target point is used as a fallback, so that the search terminates within a finite number of steps and a definite target point is output. The target airspeed is generated and limited based on the longitudinal error and the wind speed component along the lead aircraft heading, which is beneficial to improving the target point orientation and longitudinal position during formation switching.

[0026] Based on this, embodiments of this application provide a method for cooperative formation control of compound-wing unmanned aerial vehicles (UAVs), referring to... Figure 1 , Figure 1 This is a flowchart illustrating the first embodiment of the compound-wing UAV formation cooperative control method of this application.

[0027] In this embodiment, the compound-wing UAV formation cooperative control method includes steps S10~S60: Step S10: Receive status information and formation switching instructions broadcast by the lead aircraft; It should be noted that the status information is real-time flight status data that the lead aircraft periodically broadcasts in fixed-wing cruise mode to represent its current flight snapshot. The formation switching command is a control command issued by the lead aircraft when it needs to change the overall formation. It is used to control all wingmen to switch to the specified target formation. It is generated and broadcast only once when the mission is triggered. It is used to change the spatial configuration of the formation, such as switching from a straight line to a V-shape.

[0028] In specific embodiments, multi-UAV formation cooperative control is widely used in scenarios such as formation performances, collaborative mapping, collaborative inspection, and emergency search and rescue. Specifically, when a compound-wing UAV formation performs formation switching tasks in fixed-wing cruise mode, the lead aircraft can broadcast status information to the wingmen at a preset frequency. The status information includes the lead aircraft's current position (x_L, y_L, z_L), ground heading cog_L, ground speed v_L, and ground heading change rate cog_rate_L. Here, x_L, y_L, and z_L represent the lead aircraft's north, east, and altitude coordinates in the geographic coordinate system, respectively; the ground heading cog_L can be calculated from the eastward and northward ground speed components v_E and v_N using cog_L=atan2(v_E, v_N), and can be filtered after angle unwrapping; v_L represents the lead aircraft's ground speed; and cog_rate_L characterizes the change in the lead aircraft's ground heading over time, and its calculation or estimation method is determined based on the actual navigation status and flight control code.

[0029] When the lead aircraft responds to the mission process, it broadcasts a formation switching instruction CHANGE_SHAPE carrying the target formation number N_target to the wingman. The formation switching instruction is sent K times consecutively after being triggered, with the interval between adjacent transmissions being a preset retransmission interval, and the retransmission duration being no less than K-1 retransmission intervals; K and the retransmission interval are determined according to the actual link configuration.

[0030] Step S20: Determine the offset vector relative to the lead aircraft based on the formation geometry configuration corresponding to the formation switching command; It should be noted that the offset vector is the position increment of the wingman relative to the lead aircraft, including longitudinal and lateral offset components. It is used to describe the expected formation position of the wingman relative to the lead aircraft and can be directly obtained from the formation geometry. Its value and sign depend on the target formation number N_target. For example, in a straight line formation, the offset vector of a certain wingman is (Δx=-50 meters, Δy=0), and in a V-shape formation, Δx=-30 meters, Δy= ±20 meters.

[0031] It is understandable that the formation geometry configuration can be obtained from a preset formation parameter library. The preset formation parameter library is loaded through a configuration file or uploaded through a ground station during system initialization to ensure that the formation is consistent and repeatable. Therefore, the formation geometry configuration can include the relative position coordinates of each wingman in the formation, the sequence number of each wingman in the formation, and possible yaw angle offsets. Thus, according to the formation geometry configuration corresponding to the formation switching command, the wingman can immediately index the offset vector corresponding to itself under that formation from the formation geometry configuration.

[0032] In a specific embodiment, based on the target formation number corresponding to the formation switching command, the corresponding formation geometry configuration is searched from a preset formation parameter library. This formation geometry configuration includes the relative positions of each wingman within the formation. Based on this configuration, an offset vector relative to the lead aircraft is determined. This offset vector includes a longitudinal offset component and a lateral offset component. Specifically, after receiving the CHANGE_SHAPE command, wingman i parses the target formation number N_target and queries the preset formation parameter library for the offset vector (Δx_i, Δy_i) based on its own sequence number i within the formation. The preset formation parameter library can be indexed by the target formation number and the wingman's sequence number. Each element includes a longitudinal offset Δx_i and a lateral offset Δy_i. Each wingman queries its own offset vector locally based on the same target formation number, reducing the communication overhead required for the lead aircraft to send offset coordinates to each aircraft individually.

[0033] In one feasible implementation, step S20 may include steps A11-A12: Step A11: Based on the target formation number corresponding to the formation switching instruction, search for the corresponding formation geometry configuration from the preset formation parameter library. The formation geometry configuration includes the relative positional relationship of each wingman in the formation. It should be noted that the preset formation parameter library can be loaded via configuration file or uploaded via ground station during system initialization. Updating the parameter library can adjust the formation configuration. The specific storage structure and update method are determined based on the actual flight control software.

[0034] It is understandable that the relative positions of each wingman in the formation are static geometric positions uniquely determined by the offset vector stored in the preset formation parameter library, with the lead aircraft as the reference. For example, in a V-shaped formation, the relative position of the wingman to the right rear of the lead aircraft is expressed as 30 meters longitudinally backward and 20 meters laterally to the right relative to the lead aircraft, i.e. (Δx=-30, Δy=+20), which is equivalent to taking the direction of the lead aircraft's nose as the positive x-axis and the right side of the lead aircraft as the positive y-axis. This ensures that the position coordinates of all wingmen under the same formation number have a unique mathematical mapping relationship.

[0035] Step A12: Determine the offset vector relative to the lead aircraft based on the formation geometry configuration. The offset vector includes a longitudinal offset component and a lateral offset component.

[0036] Understandably, the longitudinal offset component and the lateral offset component are used together to determine the wingman's desired position relative to the lead aircraft. After the offset vector is converted into a target point in the geographic coordinate system, the lateral trajectory is processed by the fixed-wing position controller, and the longitudinal position coordination is processed by the target airspeed generation step.

[0037] Step S30: Based on the current position of the lead aircraft and the lead aircraft's heading angle to the ground in the status information, convert the offset vector into a theoretical target point; It should be noted that the theoretical target point is the geographical coordinates of the wingman's flight location in the current control cycle. That is, with the lead aircraft's current position as the origin and the lead aircraft's real-time broadcast heading angle as the rotation reference, the offset vector is projected onto the corresponding coordinate system through a rotation matrix, and then superimposed with the lead aircraft's geographical coordinates to obtain the theoretical target point that the wingman should fly to at this time, guiding the wingman to accurately reach the predetermined position during formation switching or maintenance.

[0038] It is understandable that the lead aircraft's current position is its current geographic coordinates, and the lead aircraft's heading angle is the angle between the lead aircraft's nose direction and geographic north. During the conversion process, the offset vector is rotated around the altitude axis by an angle equal to the heading angle, and then the rotated incremental coordinates are superimposed on the lead aircraft's position to obtain the geographic coordinates of the wingman's theoretical target point.

[0039] In a specific embodiment, using the lead aircraft's current position in the status information as a reference, the offset vector is rotated and transformed according to the lead aircraft's heading angle relative to the ground in the status information to obtain the offset coordinate increment; the offset coordinate increment is superimposed on the lead aircraft's current position in the status information to obtain the theoretical target point, that is, based on the lead aircraft's current position and current heading, the offset vector in the body coordinate system is rotated and translated to the geographic coordinate system to obtain the north coordinates fmt_sp_x and east coordinates fmt_sp_y of the theoretical target point, calculated using the following formula: fmt_sp_x=x_L-sin(cog_L)·Δy_i+cos(cog_L)·Δx_i fmt_sp_y=y_L+cos(cog_L)·Δy_i+sin(cog_L)·Δx_i Where x_L and y_L are the north and east positions of the lead aircraft in the geographic coordinate system, respectively; cog_L is the heading angle of the lead aircraft, defined as the clockwise angle between the nose direction and the geographic north; Δx_i is the longitudinal offset component of wingman i in the lead aircraft's body coordinate system; and Δy_i is the lateral offset component of wingman i in the lead aircraft's body coordinate system.

[0040] In practical applications, the theoretical target point can be input into the guidance and control process of the wingman to generate the input required for lateral trajectory and speed control; it can also filter the position and heading signals to reduce target point fluctuations caused by measurement noise.

[0041] In one feasible implementation, step S30 may include steps B11-B12: Step B11: Using the current position of the lead aircraft in the status information as a reference, rotate and transform the offset vector according to the lead aircraft's heading angle to the ground in the status information to obtain the offset coordinate increment; It should be noted that the offset coordinate increment is the component increment of the offset vector along the north and east directions after the offset vector is transformed from the long-range aircraft body coordinate system to the geographic north-east coordinate system.

[0042] Understandably, through two-dimensional rotation transformation, the local offset vector that changes with the lead aircraft's orientation can be mapped to the geographic coordinate system, allowing the theoretical target point to be updated as the lead aircraft's position and heading change.

[0043] Step B12: The offset coordinate increment is superimposed on the current position of the lead aircraft in the status information to obtain the theoretical target point.

[0044] It is understandable that by superimposing the offset coordinate increment onto the current position of the lead aircraft, the theoretical target point corresponding to the geometric relationship of the target formation can be obtained.

[0045] Step S40: Based on the judgment result that the theoretical target point is located in the preset forward flyable sector, iteratively extrapolate and update the current position of the lead aircraft and the heading angle of the lead aircraft to the ground in the status information until the preset termination condition is met, and obtain the target update point; It should be noted that the target update point is determined by the forward flyable sector or by the wingman position setting point determined according to a fallback rule after the upper limit of the prediction time has been reached. The forward flyable sector determination is used to filter the direction of the target connection and is not equivalent to proof of complete dynamic reachability, trajectory safety, or collision safety.

[0046] Understandably, the forward flyable sector is a directional filtering area formed by the wingman's current position as the vertex, the wingman's current speed direction as the center line, and the preset sector half-angle, used to determine the positional relationship of the target point relative to the wingman's current direction of movement.

[0047] In a specific embodiment, a preset initial prediction duration is obtained, which is 0.3 to 1 second, for example, 0.5 seconds. Based on the normalized inner product of the direction vector of the theoretical target point relative to the wingman's current position and the wingman's velocity vector, it is determined whether the theoretical target point is located within a preset forward flyable sector. The normalized inner product is expressed as: d=((fmt_sp_x-x_F)·v_x+(fmt_sp_y-y_F)·v_y) / (‖fmt_sp-pos_F‖·‖v‖) Where fmt_sp_x and fmt_sp_y are the north and east coordinates of the theoretical target point, x_F and y_F are the north and east coordinates of the wingman's current position, v_x and v_y are the north and east components of the wingman's velocity vector, ‖fmt_sp-pos_F‖ is the distance between the theoretical target point and the wingman's current position, and ‖v‖ is the magnitude of the wingman's velocity. When the theoretical target point coincides with the wingman's current position, the theoretical target point is directly used as the target update point; in the fixed-wing cruise state where the two do not coincide and the wingman's velocity vector magnitude is greater than zero, the normalized inner product d is calculated.

[0048] The determination condition is d>cos(α). Here, α is a preset forward sector half-angle, which can be configured in combination with the wingman's cruise speed, minimum turning radius and desired attitude adjustment time, and the value range is 30° to 60°, for example 45°.

[0049] The preset forward sector half-angle is used for direction filtering, and its specific configuration value can be determined according to the aircraft parameters and actual flight verification results.

[0050] If the theoretical target point passes the judgment, fmt_sp will be used as the wingman's position setting point pos_sp; if it fails the judgment, the lead aircraft's predicted position and predicted heading will be extrapolated from the preset initial prediction time according to the preset step size, and the sector judgment will be re-performed for the target candidate points obtained accordingly.

[0051] The above process continues until the target candidate point passes the judgment, or the target prediction time reaches the preset time limit. If the target still fails to pass even after reaching the limit, the original theoretical target point is used as a fallback output.

[0052] At this point, assuming that the lead aircraft's ground speed and rate of change of heading remain constant over a short period of time, the predicted position is approximated using the midpoint integral, and the predicted heading is calculated based on the rate of change of heading: x_L_est=x_L+v_L·cos(cog_L+0.5·cog_rate_L·dt)·dt y_L_est=y_L+v_L·sin(cog_L+0.5·cog_rate_L·dt)·dt cog_L_est=cog_L+cog_rate_L·dt Where x_L and y_L are the geographic coordinates of the lead aircraft at the current moment, v_L is the current speed of the lead aircraft, cog_L is the current heading angle of the lead aircraft, cog_rate_L is the rate of change of the current heading angle of the lead aircraft, and dt is the extrapolation duration.

[0053] The target point (fmt_sp_x_new, fmt_sp_y_new) can be recalculated based on (x_L_est, y_L_est) and cog_L_est.

[0054] For the new target candidate point fmt_sp_new, determine if it is a duplicate sector and check if d>cos(α): If the determination is successful, fmt_sp_new is set as the wingman's position setpoint pos_sp, the iteration is exited and subsequent control is executed; If the judgment fails and the current prediction duration is less than the preset duration limit, then let dt = dt + Δdt, and recalculate the lead aircraft's predicted position, predicted course, and target candidate points; If the target candidate point fails to pass the judgment when dt reaches the preset time limit dt_max, the iteration stops, and the original theoretical target point is used as pos_sp. dt_max can be configured in the range of 0.5 to 5 seconds, for example, 2 seconds.

[0055] When 0 < Δdt ≤ dt_max, the upper limit of the number of iterations for the discrete step size search is determined by the ratio of dt_max to Δdt and whether the dt_max endpoint is tested separately; the iteration stops after reaching the termination endpoint, thus ensuring that the search terminates within a finite number of steps.

[0056] The aforementioned sector determination and finite-step search are used to improve the positional relationship of the target point relative to the current direction of movement of the wingman, and to provide a definite fallback output when the search fails.

[0057] In one feasible implementation, step S40 may include steps C11-C14: Step C11: Obtain the current position, velocity vector, and preset sector half-angle of each wingman; It should be noted that the current position of each wingman is the spatial coordinate calculated by the wingman within the current control cycle. The velocity vector is the velocity vector of the wingman relative to the ground at the current moment, including the magnitude and direction of the velocity, representing the actual movement trend of the wingman. The preset sector half angle is a pre-set angle threshold, which represents the half angle formed by extending this angle to the left and right of the current velocity direction of the wingman. It is used to filter the target direction that the wingman can fly directly to without large-scale maneuvers. The larger the preset half angle, the greater the angle of deviation of the target point from the current heading.

[0058] Step C12: Calculate the normalized inner product of the direction vector from the current position of each wingman to the theoretical target point and the velocity vector; It should be noted that the judgment result is used to characterize whether the theoretical target point is within a preset angle range relative to the current speed direction of the wingman.

[0059] It is understood that the normalized inner product of the direction vector of the theoretical target point and the velocity vector is the dot product calculated by normalizing the direction vector of the wingman's current position pointing to the theoretical target point and the wingman's current velocity vector, respectively. It can be expressed as the cosine of the angle between the target point direction and the wingman's current velocity direction.

[0060] Step C13: When the normalized inner product is greater than the cosine of the preset sector half-angle, determine that the theoretical target point is located within the preset forward flyable sector, and determine the theoretical target point as the target update point. It is understandable that when the normalized inner product is greater than the cosine of the preset sector half-angle, it means that the angle between the direction of the theoretical target point and the direction of the wingman's current speed is less than the sector half-angle. That is, the target point falls within the range that can be flown directly with the wingman's current heading as the center. At this time, the wingman does not need to make a large turn or detour and can fly directly to the target point under the existing maneuverability constraints. Therefore, the theoretical target point can be directly determined as the target update point and used as the position setting point of the current control cycle.

[0061] Step C14: When the normalized inner product is not greater than the cosine of the preset sector half angle, starting from the preset initial prediction duration, the target prediction duration is incremented by the preset step size, and the predicted position and predicted heading of the lead aircraft are iteratively extrapolated based on the current position of the lead aircraft, the heading angle of the lead aircraft to the ground, and the target prediction duration in the status information to obtain the target update point.

[0062] It should be noted that the initial prediction duration is the starting time step of the iterative extrapolation process, usually set to the minimum response time of fixed-wing attitude adjustment, typically 0.5 seconds. Setting a reasonable initial prediction duration can avoid frequent invalid iterations due to too small a step size, or a decrease in extrapolation accuracy due to too large a step size. The target prediction duration is the prediction duration value that finally meets the sector determination conditions after iterative search, thereby gradually extrapolating to pull the target point into the flyable sector, thus obtaining a feasible prediction duration that meets the maneuver constraints.

[0063] Understandably, when the normalized inner product is not greater than the cosine of the half-angle of the preset sector, it indicates that the theoretical target point falls outside the wingman's forward flyable sector. If the wingman were to fly directly to this point, it would need to make a sharp turn or even circle, which does not meet the maneuver constraints and rapid formation switching requirements of fixed-wing UAVs. Since the lead aircraft continues to fly forward, the target point will also change continuously with the lead aircraft's position and heading. Therefore, the target point can be recalculated by predicting the lead aircraft's position and heading some time in the future, gradually bringing the candidate point into the wingman's directly flyable sector.

[0064] In one feasible implementation, the state information also includes the lead aircraft's ground speed and the lead aircraft's heading change rate. The lead aircraft's ground speed is the velocity vector of the lead aircraft relative to the ground coordinate system, used to predict the lead aircraft's position change over a future period of time. The lead aircraft's heading change rate is the rate of change of the lead aircraft's heading angle over time, characterizing the lead aircraft's current maneuvering trend, such as whether it is turning, the direction of the turn, and the speed, used to predict the lead aircraft's heading angle at the end of the prediction period, so that the extrapolated predicted heading is closer to the lead aircraft's actual motion state.

[0065] Step C14 may include steps D11 to D13: Step D11: Calculate the predicted position and corresponding predicted heading of the lead aircraft based on its current position, ground speed, ground heading angle, heading change rate, and target prediction duration. It should be noted that the predicted position of the lead aircraft is the predicted position of the lead aircraft at a certain future moment, and the predicted heading of the lead aircraft is the heading predicted by linear extrapolation of the heading angle of the lead aircraft along the current heading rate of change.

[0066] Step D12: Determine the target candidate point based on the predicted position and predicted heading of the lead aircraft, and re-perform the forward flyable sector determination for the target candidate point; It should be noted that when a target candidate point passes the sector determination, it is used as the target update point. If a target candidate point fails the determination and the current target prediction time is less than the preset time limit, the target prediction time is increased and the iteration continues.

[0067] Step D13: If the target candidate point passes the forward flyable sector determination, then the target candidate point is used as the target update point; if the target candidate point fails the forward flyable sector determination and the target prediction time is less than the preset time limit, then the target prediction time is increased by the preset step size and the iteration continues; if the target candidate point fails the forward flyable sector determination and the target prediction time reaches the preset time limit, then the iteration stops, and the original theoretical target point calculated based on the current position and current heading angle of the lead aircraft is used as the target update point.

[0068] Understandably, the aforementioned mutually exclusive branches ensure that each search yields a unique target update point output; the failover point may be located outside the forward sector, and subsequent guidance will still be provided by the fixed-wing position controller.

[0069] Step S50: Obtain the feedforward wind speed component, and calculate the target airspeed based on the state information, the longitudinal error of the target update point projected along the heading angle of the lead aircraft, and the feedforward wind speed component. It should be noted that the feedforward wind speed component is the projection component of the environmental wind speed vector onto the current heading direction of the lead aircraft. When the northward and eastward components represent the air mass velocity blowing in the corresponding direction, the positive projection represents the downwind component, which is subtracted in the target airspeed calculation to reduce the required airspeed; the negative projection represents the headwind component, which is subtracted to increase the required airspeed.

[0070] It is understood that the target airspeed is the wingman's desired speed of motion relative to the air in order to propel the wingman to fly at a suitable airspeed.

[0071] Additionally, the longitudinal error is the projection of the difference vector between the wingman's current position and the target update point onto the lead aircraft's ground-to-the-heading direction. A positive longitudinal error indicates that the wingman is ahead of the target position along the lead aircraft's ground-to-the-heading direction, while a negative longitudinal error indicates that the wingman is behind the target position along the lead aircraft's ground-to-the-heading direction.

[0072] In a specific embodiment, the current position coordinates (x_F, y_F) of the wingman and the preset longitudinal scaling gain Kp_lon are obtained.

[0073] The preset longitudinal proportional gain is used to determine the strength of the longitudinal error's effect on the target airspeed correction.

[0074] The preset longitudinal proportional gain is an adjustable parameter configured before flight.

[0075] Its specific value and dimensions are determined based on the error unit, normalization method, airspeed range of the aircraft model, and longitudinal response requirements in the actual software.

[0076] The acceleration and deceleration processes of a fixed-wing platform are both constrained by the flight envelope, with the deceleration process also subject to a minimum safe airspeed limit.

[0077] The difference information is calculated based on the wingman's position information and the target update point, that is, the difference between the wingman's position and the target update point (pos_sp_x, pos_sp_y) is calculated, and then projected along the lead aircraft's heading angle to obtain the longitudinal error, which is expressed as: lon_err=(x_F-pos_sp_x)·cos(cog_L)+(y_F-pos_sp_y)·sin(cog_L) Where lon_err > 0 indicates that the wingman is ahead of the target position, and lon_err < 0 indicates that the wingman is behind. The ambient wind speed vector (wind_e, wind_n) can be obtained from the wind speed estimation results of the wingman's flight control; when its components represent the air mass blowing eastward and northward, the feedforward wind speed components are obtained by projecting the ambient wind speed along the lead aircraft's heading towards the ground: wind_spd_proj=wind_e·sin(cog_L)+wind_n·cos(cog_L) Orthogonal projection represents the downwind component, which is subtracted from the target airspeed calculation; negative projection represents the headwind component, which increases the target airspeed after subtracting the negative value.

[0078] The target airspeed is calculated based on the longitudinal error of the projection of the difference information along the heading angle of the lead aircraft, the feedforward wind speed component, and the gain information. target_spd=v_L-wind_spd_proj-Kp_lon·lon_err Where v_L is the ground speed of the lead aircraft.

[0079] This leads to the formation of longitudinal airspeed settings for wingmen, which helps improve longitudinal position coordination during formation switching under wind disturbance and maneuvering conditions.

[0080] In one feasible implementation, step S50 may include steps E11 to E14: Step E11: Obtain the ambient wind speed vector, project the ambient wind speed vector onto the lead aircraft's ground heading direction, and obtain the feedforward wind speed component. It should be noted that the environmental wind speed vector can be obtained from the wind speed estimation results provided by the wingman flight control, including north and east wind speed components.

[0081] Step E12: Project the difference vector relative to the target update point onto the lead aircraft's ground heading to obtain the longitudinal error, wherein a positive longitudinal error indicates that the wingman is ahead of the target update point, and a negative longitudinal error indicates that the wingman is behind the target update point; It should be noted that a positive longitudinal error indicates that the wingman is ahead, while a negative longitudinal error indicates that the wingman is behind.

[0082] Step E13: Calculate the target airspeed based on the lead aircraft's ground speed, the feedforward wind speed component, the preset longitudinal proportional gain, and the longitudinal error in the status information; Understandably, the target airspeed correction is formed based on the longitudinal position deviation and wind speed projection, and then the minimum and maximum cruise airspeeds need to be combined for amplitude limiting.

[0083] Step E14: When the longitudinal error is greater than a negative preset deceleration margin, the target airspeed is set to a preset minimum cruise airspeed; the target airspeed is limited between the preset minimum cruise airspeed and the preset maximum cruise airspeed.

[0084] Understandably, the preset minimum cruise airspeed is a lower limit set below which further deceleration is not permitted. This ensures that the wingman can maintain stable level flight at all times and has the ability to effectively respond to target speed commands. When the longitudinal error indicates that the wingman has over-consumed the deceleration requirement and no further significant deceleration is needed, the target airspeed is directly set to this minimum value to avoid entering the low-speed danger zone. The preset maximum cruise airspeed, on the other hand, is an upper limit set within the cruise envelope allowed for formation flight. This prevents the wingman from exceeding the safe flight envelope due to blind pursuit or excessive acceleration. It is used to saturate and constrain the target airspeed, ensuring that the output target airspeed always falls within a safe, reasonable, and controllable range.

[0085] Step S60: When the longitudinal error is greater than the negative preset deceleration margin, the target airspeed is set to the preset minimum cruise airspeed, and the target airspeed is limited between the preset minimum cruise airspeed and the preset maximum cruise airspeed. Based on the limited target airspeed, the airspeed setting value of the wingman during formation switching is generated.

[0086] It should be noted that a positive value of the longitudinal error indicates that the wingman is ahead, and a negative value indicates that the wingman is behind; the preset deceleration margin is a positive value, used to limit the longitudinal error range for triggering the preset minimum cruise airspeed.

[0087] In a specific embodiment, the target airspeed is first calculated based on the longitudinal error, wind speed projection, and a preset longitudinal proportional gain; when the longitudinal error is greater than a negative preset deceleration margin, the target airspeed is set to a preset minimum cruise airspeed. if(lon_err>-decel_margin) then target_spd=arspd_min The decel_margin can be set to 5 to 30 meters, with 10 meters being the preferred value.

[0088] If the above conditions are not met, retain the target airspeed calculated in step S50; then uniformly limit the target airspeed.

[0089] At this point, airspeed saturation can be achieved, which is represented as: target_spd=constrain(target_spd, arspd_min, arspd_max) Among them, arspd_min is typically 15m / s to 20m / s, and arspd_max is typically 25m / s to 35m / s.

[0090] In one feasible implementation, the target update point, virtual previous waypoint, and target airspeed can be provided to the fixed-wing position controller through a customized wingman guidance interface; the specific message fields and decoding relationships are determined according to the actual flight control software interface.

[0091] The fixed-wing position controller performs lateral guidance and longitudinal speed control based on the received current waypoint, previous waypoint, and target airspeed; the data paths for each control variable to enter the actual guidance and speed control modules are based on the customized flight control code.

[0092] Furthermore, the extrapolation method can employ other bounded prediction methods, and the search method can employ other bounded discrete search methods; when using binary search, the decision quantity, search interval, and termination condition with monotonicity should be predefined. Command retransmission and message interfaces for different flight control platforms can be configured according to the actual link and software architecture.

[0093] This embodiment proposes a formation cooperative control method for compound-wing UAVs. This application performs forward sector determination on theoretical target points, and extrapolates the position and heading of the lead aircraft by increasing the prediction time when the determination fails, until the target candidate point passes the determination or reaches the upper limit of the prediction time. If the target still fails when the upper limit is reached, the original theoretical target point is used as a fallback, so that the search terminates within a finite number of steps and a definite target point is output. The target airspeed is generated and limited based on the longitudinal error and the wind speed component along the heading of the lead aircraft, which is beneficial to improving the direction and longitudinal position of the target point during formation switching.

[0094] Based on the first embodiment of this application, in the second embodiment of this application, the same or similar content as the first embodiment can be referred to the above description, and will not be repeated hereafter.

[0095] In this embodiment, refer to Figure 2 , Figure 2 The flowchart provided for Embodiment 2 of the compound-wing UAV formation cooperative control method of this application also includes steps S70~S100: Step S70: Obtain the preset backtracking distance; The preset backoff distance is used to construct a virtual previous waypoint in the opposite direction of the lead aircraft's current heading, based on the target update point. This backoff distance is a parameter configured before flight or preset in the program, and is not generated online by the proportional or integral component of the longitudinal error, nor is it used to modify the target update point or target airspeed.

[0096] Understandably, the preset backoff distance is used to determine the geometric interval between the virtual previous waypoint and the target update point.

[0097] In a specific embodiment, using the target update point pos_sp as a reference, the aircraft reverses its current heading by a preset distance d_back to obtain the virtual previous waypoint prev_wp. d_back can be configured within the range of 5 to 50 meters, for example, 20 meters; the specific value is determined based on the aircraft's turning characteristics and approach route requirements.

[0098] Step S80: Based on the lead aircraft's ground heading angle, the target update point, and the preset backtracking distance in the status information, determine the virtual previous waypoint set in the opposite direction of the lead aircraft's ground heading; It should be noted that the virtual previous waypoint is set in the opposite direction of the lead aircraft's current heading, based on the target update point, and is used to provide the fixed-wing position controller with the route direction from the previous waypoint to the current target point.

[0099] In a specific embodiment, using the target update point pos_sp as a reference, and based on the lead aircraft's current heading angle cog_L and the preset backoff distance d_back, the virtual previous waypoint prev_wp is generated through the following geometric transformation: prev_wp_x=pos_sp_x-cos(cog_L)·d_back prev_wp_y=pos_sp_y-sin(cog_L)·d_back Where prev_wp_x and prev_wp_y are the north and east coordinates of the virtual previous waypoint, respectively, and pos_sp_x and pos_sp_y are the north and east coordinates of the target update point, respectively; the target update point is the wingman position setting point determined after formation offset transformation, forward sector determination and necessary iterative extrapolation; d_back is the preset back-off distance.

[0100] This embodiment constructs a virtual previous waypoint in the opposite direction of the lead aircraft's heading from the target update point. This provides the fixed-wing position controller with an approach route direction consistent with the lead aircraft's heading, which helps reduce the likelihood of wingmen cutting in from the side to the target point. The virtual previous waypoint does not change the target update point or the target airspeed.

[0101] Step S90: The target update point is used as the current waypoint, the virtual previous waypoint is used as the previous waypoint, and guidance input is provided to the fixed-wing position controller in combination with the target airspeed. Understandably, the virtual previous waypoint is used to define the route direction approaching the target update point, and is not used as the target point for continuous tracking by the wingman. The fixed-wing position controller performs guidance and speed control based on the current waypoint, the previous waypoint, and the target airspeed.

[0102] Step S100: Guide the wingman to approach the target update point along the lead aircraft's ground heading angle.

[0103] This embodiment proposes a formation cooperative control method for compound-wing UAVs. This application obtains a preset backtracking distance, uses the target update point as a reference, and constructs a virtual previous waypoint in the opposite direction of the lead aircraft's ground heading. The target update point is used as the current waypoint, and the virtual previous waypoint is used as the previous waypoint. Guidance input is provided to the fixed-wing position controller in combination with the target airspeed. The virtual previous waypoint is used to define the route direction approaching the target update point. It is not used as the target point for continuous tracking by the wingman, nor does it change the target update point or the target airspeed.

[0104] It is understandable that, such as Figure 3 As shown, Figure 3 This is a guidance diagram of the formation cooperative control method for compound-wing UAVs in this application. When the original theoretical target point fails the forward sector judgment, the system extrapolates the lead aircraft's position and heading by increasing the prediction time, and recalculates the target candidate points based on the lead aircraft's predicted state, until the target candidate points pass the judgment or the upper limit of the prediction time is reached. This judgment is a target connection direction screening and is not equivalent to complete dynamic reachability or trajectory safety proof.

[0105] This application also provides a compound-wing UAV formation cooperative control device, please refer to... Figure 4 The composite-wing UAV formation coordination control device includes: Receiver module 10 is used to receive status information and formation switching instructions broadcast by the primary aircraft; The determination module 20 is used to determine the offset vector relative to the lead aircraft based on the formation geometry configuration corresponding to the formation switching instruction; The conversion module 30 is used to convert the offset vector into a theoretical target point based on the current position of the lead aircraft and the lead aircraft's heading angle to the ground in the status information. The update module 40 is used to iteratively update the current position of the lead aircraft and the heading angle of the lead aircraft to the ground in the status information according to the judgment result that the theoretical target point is located in the preset forward flyable sector, until the preset termination condition is met, and the target update point is obtained. Calculation module 50 is used to obtain the feedforward wind speed component and calculate the target airspeed based on the state information, the longitudinal error of the target update point projected along the heading angle of the lead aircraft, and the feedforward wind speed component. The execution module 60 is used to set the target airspeed to a preset minimum cruise airspeed and limit the target airspeed between the preset minimum cruise airspeed and the preset maximum cruise airspeed when the longitudinal error is greater than a negative preset deceleration margin, and to generate the airspeed setting value of the wingman during formation switching based on the limited target airspeed.

[0106] The determining module 20 is further configured to search for the corresponding formation geometry configuration from the preset formation parameter library according to the target formation number corresponding to the formation switching instruction. The formation geometry configuration includes the relative positional relationship of each wingman in the formation. An offset vector relative to the lead aircraft is determined based on the formation geometry, the offset vector including a longitudinal offset component and a lateral offset component.

[0107] The conversion module 30 is further configured to use the current position of the lead aircraft in the status information as a reference to rotate and convert the offset vector according to the lead aircraft's heading angle to the ground in the status information to obtain the offset coordinate increment; The offset coordinate increment is superimposed on the current position of the lead aircraft in the status information to obtain the theoretical target point.

[0108] The update module 40 is also used to obtain the current position, velocity vector and preset sector half angle of each wingman; Calculate the normalized inner product of the direction vector from the current position of each wingman to the theoretical target point and the velocity vector; When the normalized inner product is greater than the cosine of the preset sector half-angle, the theoretical target point is determined to be located within the preset forward flyable sector, and the theoretical target point is determined as the target update point. When the normalized inner product is not greater than the cosine of the preset sector half angle, starting from the preset initial prediction duration, the target prediction duration is incremented by the preset step size, and the predicted position and predicted heading of the lead aircraft are iteratively extrapolated based on the current position of the lead aircraft, the lead aircraft's heading angle to the ground, and the target prediction duration to obtain the target update point.

[0109] The update module 40 is also used to calculate the predicted position of the lead aircraft and the corresponding predicted heading of the lead aircraft based on the lead aircraft's current position, the lead aircraft's ground speed, the lead aircraft's ground heading angle, the lead aircraft's heading change rate, and the target prediction time. Based on the predicted position and predicted course of the lead aircraft, target candidate points are determined, and the forward flyable sector determination is re-executed for the target candidate points; If the target candidate point passes the forward flyable sector determination, then the target candidate point is used as the target update point; if the target candidate point fails the forward flyable sector determination and the target prediction time is less than the preset time limit, then the target prediction time is increased by the preset step size and the iteration continues; if the target candidate point fails the forward flyable sector determination and the target prediction time reaches the preset time limit, then the iteration stops, and the original theoretical target point calculated based on the current position and current heading angle of the lead aircraft is used as the target update point.

[0110] The calculation module 50 is also used to obtain the environmental wind speed vector, project the environmental wind speed vector onto the flight direction of the lead aircraft to obtain the feedforward wind speed component; The difference vector relative to the target update point is projected onto the lead aircraft's ground heading to obtain the longitudinal error, wherein a positive longitudinal error indicates that the wingman is ahead of the target update point, and a negative longitudinal error indicates that the wingman is behind the target update point; The target airspeed is calculated based on the lead aircraft's ground speed, the feedforward wind speed component, the preset longitudinal proportional gain, and the longitudinal error in the status information. When the longitudinal error is greater than the negative preset deceleration margin, the target airspeed is set to the preset minimum cruise airspeed; the target airspeed is limited between the preset minimum cruise airspeed and the preset maximum cruise airspeed.

[0111] The execution module 60 is also used to obtain a preset back-off distance; Based on the lead aircraft's ground heading angle, the target update point, and the preset backtracking distance in the status information, a virtual previous waypoint is determined in the opposite direction of the lead aircraft's ground heading. The target update point is used as the current waypoint, the virtual previous waypoint is used as the previous waypoint, and guidance input is provided to the fixed-wing position controller in combination with the target airspeed. Guide the wingman to approach the target update point along the lead aircraft's ground heading angle.

[0112] The compound-wing UAV formation cooperative control device provided in this application, employing the compound-wing UAV formation cooperative control method in the above embodiments, can solve the technical problem of how to improve the target point orientation during formation switching to maintain the same longitudinal position. Compared with the prior art, the beneficial effects of the compound-wing UAV formation cooperative control device provided in this application are the same as those of the compound-wing UAV formation cooperative control method provided in the above embodiments, and other technical features in the compound-wing UAV formation cooperative control device are the same as those disclosed in the methods of the above embodiments, and will not be repeated here.

[0113] This application provides a compound-wing UAV formation cooperative control device, which includes: at least one processor; and a memory communicatively connected to the at least one processor; wherein the memory stores instructions executable by the at least one processor, and the instructions are executed by the at least one processor to enable the at least one processor to execute the compound-wing UAV formation cooperative control method in Embodiment 1 above.

[0114] The following is for reference. Figure 5The diagram illustrates a structural schematic suitable for implementing the compound-wing UAV formation cooperative control device in the embodiments of this application. The compound-wing UAV formation cooperative control device in the embodiments of this application may include, but is not limited to, mobile terminals such as mobile phones, laptops, digital broadcast receivers, PDAs (Personal Digital Assistants), PMPs (Portable Media Players), vehicle terminals (e.g., vehicle navigation terminals), and fixed terminals such as digital TVs and desktop computers. Figure 5 The compound-wing UAV formation cooperative control device shown is merely an example and should not impose any limitations on the functionality and scope of use of the embodiments of this application.

[0115] like Figure 5 As shown, the compound-wing UAV formation coordination control device may include a processing unit 1001 (e.g., a central processing unit, a graphics processing unit, etc.), which can perform various appropriate actions and processes according to programs stored in ROM (Read Only Memory) 1002 or programs loaded from storage device 1003 into RAM (Random Access Memory) 1004. RAM 1004 also stores various programs and data required for the operation of the compound-wing UAV formation coordination control device. The processing unit 1001, ROM 1002, and RAM 1004 are interconnected via bus 1005. Input / output (I / O) interface 1006 is also connected to the bus. Typically, the following systems can be connected to I / O interface 1006: input devices 1007 including, for example, touchscreens, touchpads, keyboards, mice, image sensors, microphones, accelerometers, gyroscopes, etc.; output devices 1008 including, for example, liquid crystal displays (LCDs), speakers, vibrators, etc.; storage devices 1003 including, for example, magnetic tapes, hard disks, etc.; and communication devices 1009. Communication device 1009 allows the compound-wing UAV formation coordination control device to communicate wirelessly or wiredly with other devices to exchange data. Although a compound-wing UAV formation coordination control device with various systems is shown in the figure, it should be understood that it is not required to implement or possess all the systems shown. More or fewer systems can be implemented alternatively.

[0116] Specifically, according to the embodiments disclosed in this application, the processes described above with reference to the flowcharts can be implemented as computer software programs. For example, embodiments disclosed in this application include a computer program product comprising a computer program carried on a computer-readable medium, the computer program containing program code for performing the methods shown in the flowcharts. In such embodiments, the computer program can be downloaded and installed from a network via a communication device, or installed from storage device 1003, or installed from ROM 1002. When the computer program is executed by processing device 1001, it performs the functions defined in the methods of the embodiments disclosed in this application.

[0117] The compound-wing UAV formation cooperative control device provided in this application, employing the compound-wing UAV formation cooperative control method in the above embodiments, can solve the technical problem of how to improve the target point orientation during formation switching to maintain the same longitudinal position. Compared with the prior art, the beneficial effects of the compound-wing UAV formation cooperative control device provided in this application are the same as those of the compound-wing UAV formation cooperative control method provided in the above embodiments, and other technical features in this compound-wing UAV formation cooperative control device are the same as those disclosed in the previous embodiment method, and will not be repeated here.

[0118] It should be understood that the various parts disclosed in this application can be implemented using hardware, software, firmware, or a combination thereof. In the description of the above embodiments, specific features, structures, materials, or characteristics can be combined in any suitable manner in one or more embodiments or examples.

[0119] The above description is merely a specific embodiment of this application, but the scope of protection of this application is not limited thereto. Any variations or substitutions that can be easily conceived by those skilled in the art within the scope of the technology disclosed in this application should be included within the scope of protection of this application. Therefore, the scope of protection of this application should be determined by the scope of the claims.

[0120] This application provides a computer-readable storage medium having computer-readable program instructions (i.e., a computer program) stored thereon, the computer-readable program instructions being used to execute the compound-wing UAV formation cooperative control method in the above embodiments.

[0121] The computer-readable storage medium provided in this application may be, for example, a USB flash drive, but is not limited to, electrical, magnetic, optical, electromagnetic, infrared, or semiconductor systems, devices, or any combination thereof. More specific examples of computer-readable storage media may include, but are not limited to: electrical connections having one or more wires, portable computer disks, hard disks, random access memory (RAM), read-only memory (ROM), erasable programmable read-only memory (EPROM or flash memory), optical fiber, portable compact disk read-only memory (CD-ROM), optical storage devices, magnetic storage devices, or any suitable combination thereof. In this embodiment, the computer-readable storage medium may be any tangible medium containing or storing a program that can be used by or in conjunction with an instruction execution system, system, or device. The program code contained on the computer-readable storage medium may be transmitted using any suitable medium, including but not limited to: wires, optical cables, RF (Radio Frequency), etc., or any suitable combination thereof.

[0122] The aforementioned computer-readable storage medium may be included in the compound-wing UAV formation coordination control device; or it may exist independently and not be assembled into the compound-wing UAV formation coordination control device.

[0123] The aforementioned computer-readable storage medium carries one or more programs that, when executed by the compound-wing UAV formation coordination control device, cause the compound-wing UAV formation coordination control device to: receive status information and formation switching instructions broadcast by the lead aircraft; determine the offset vector relative to the lead aircraft based on the formation geometry configuration corresponding to the formation switching instructions; convert the offset vector into a theoretical target point based on the lead aircraft's current position and ground heading angle in the status information; and iteratively extrapolate further based on the judgment result that the theoretical target point is located in a preset forward flyable sector. The current position of the lead aircraft and its heading angle relative to the ground in the new status information are used until a preset termination condition is met to obtain the target update point; the feedforward wind speed component is obtained, and the target airspeed is calculated based on the status information, the longitudinal error of the target update point projected along the heading angle of the lead aircraft, and the feedforward wind speed component; when the longitudinal error is greater than a negative preset deceleration margin, the target airspeed is set to a preset minimum cruise airspeed, and the target airspeed is limited between the preset minimum cruise airspeed and the preset maximum cruise airspeed. The airspeed setting value of the wingman during formation switching is generated based on the limited target airspeed.

[0124] Computer program code for performing the operations of this application can be written in one or more programming languages ​​or a combination thereof, including object-oriented programming languages ​​such as Java, Smalltalk, and C++, and conventional procedural programming languages ​​such as the "C" language or similar programming languages. The program code can be executed entirely on the user's computer, partially on the user's computer, as a standalone software package, partially on the user's computer and partially on a remote computer, or entirely on a remote computer or server. In cases involving remote computers, the remote computer can be connected to the user's computer via any type of network—including a Local Area Network (LAN) or a Wide Area Network (WAN)—or can be connected to an external computer (e.g., via the Internet using an Internet service provider).

[0125] The flowcharts and block diagrams in the accompanying drawings illustrate the architecture, functionality, and operation of possible implementations of systems, methods, and computer program products according to various embodiments of this application. In this regard, each block in a flowchart or block diagram may represent a module, segment, or portion of code containing one or more executable instructions for implementing a specified logical function. It should also be noted that in some alternative implementations, the functions indicated in the blocks may occur in a different order than those indicated in the drawings. For example, two consecutively indicated blocks may actually be executed substantially in parallel, and they may sometimes be executed in reverse order, depending on the functions involved. It should also be noted that each block in the block diagrams and / or flowcharts, and combinations of blocks in the block diagrams and / or flowcharts, can be implemented using a dedicated hardware-based system that performs the specified function or operation, or using a combination of dedicated hardware and computer instructions.

[0126] The modules described in the embodiments of this application can be implemented in software or hardware. The names of the modules do not necessarily limit the functionality of the unit itself.

[0127] The readable storage medium provided in this application is a computer-readable storage medium that stores computer-readable program instructions (i.e., a computer program) for executing the above-described compound-wing UAV formation cooperative control method. This program solves the technical problem of how to improve the target point orientation during formation switching to maintain the same longitudinal position. Compared with the prior art, the beneficial effects of the computer-readable storage medium provided in this application are the same as those of the compound-wing UAV formation cooperative control method provided in the above embodiments, and will not be repeated here.

[0128] The above description is only a part of the embodiments of this application and does not limit the scope of this application. All equivalent structural transformations made under the technical concept of this application and using the content of this application specification and drawings, or direct / indirect applications in other related technical fields, are included within the protection scope of this application.

Claims

1. A compound wing UAV formation cooperative control method, characterized in that, The method includes: Receive status information and formation switching instructions broadcast by the lead aircraft; Based on the formation geometry configuration corresponding to the formation switching command, determine the offset vector relative to the lead aircraft; Based on the lead aircraft's current position and ground heading angle in the status information, the offset vector is converted into a theoretical target point; Based on the judgment result that the theoretical target point is located in the preset forward flyable sector, the current position of the lead aircraft and the heading angle of the lead aircraft to the ground in the status information are iteratively updated step by step until the preset termination condition is met, and the target update point is obtained. Obtain the feedforward wind speed component, and calculate the target airspeed based on the state information, the longitudinal error of the target update point projected along the heading angle of the lead aircraft, and the feedforward wind speed component. When the longitudinal error is greater than the negative preset deceleration margin, the target airspeed is set to the preset minimum cruise airspeed, and the target airspeed is limited between the preset minimum cruise airspeed and the preset maximum cruise airspeed. Based on the limited target airspeed, the airspeed setting value of the wingman during formation switching is generated.

2. The method of claim 1, wherein, The step of determining the offset vector relative to the lead aircraft based on the formation geometry configuration corresponding to the formation switching command includes: According to the target formation number corresponding to the formation switching command, the corresponding formation geometry configuration is searched from the preset formation parameter library. The formation geometry configuration includes the relative positional relationship of each wingman in the formation. An offset vector relative to the lead aircraft is determined based on the formation geometry, the offset vector including a longitudinal offset component and a lateral offset component.

3. The method of claim 1, wherein, The step of converting the offset vector into a theoretical target point based on the lead aircraft's current position and ground heading angle in the status information includes: Using the current position of the lead aircraft in the status information as a reference, the offset vector is rotated and transformed according to the lead aircraft's heading angle to the ground in the status information to obtain the offset coordinate increment; The offset coordinate increment is superimposed on the current position of the lead aircraft in the status information to obtain the theoretical target point.

4. The method of claim 1, wherein, The step of iteratively updating the lead aircraft's current position and ground heading angle in the status information based on the judgment result that the theoretical target point is located in a preset forward flyable sector, until a preset termination condition is met, to obtain the target update point includes: Obtain the current position, velocity vector, and preset sector half-angle of each wingman; Calculate the normalized inner product of the direction vector from the current position of each wingman to the theoretical target point and the velocity vector; When the normalized inner product is greater than the cosine of the preset sector half-angle, the theoretical target point is determined to be located within the preset forward flyable sector, and the theoretical target point is determined as the target update point. When the normalized inner product is not greater than the cosine of the preset sector half angle, starting from the preset initial prediction duration, the target prediction duration is incremented by the preset step size, and the predicted position and predicted heading of the lead aircraft are iteratively extrapolated based on the current position of the lead aircraft, the lead aircraft's heading angle to the ground, and the target prediction duration to obtain the target update point.

5. The method as described in claim 4, characterized in that, The status information also includes the lead aircraft's ground speed and the lead aircraft's rate of change of heading; The process of iteratively extrapolating the lead aircraft's predicted position and predicted heading based on the current position and ground heading of the lead aircraft in the state information, and the target prediction time, to obtain the target update point includes: Based on the lead aircraft’s current position, lead aircraft’s ground speed, lead aircraft’s ground heading angle, lead aircraft’s heading change rate, and target prediction time, calculate the lead aircraft’s predicted position and the corresponding lead aircraft’s predicted heading. Based on the predicted position and predicted course of the lead aircraft, target candidate points are determined, and the forward flyable sector determination is re-executed for the target candidate points; If the target candidate point is determined by the forward flyable sector, then the target candidate point is used as the target update point; If the target candidate point fails to pass the forward flyable sector determination and the target prediction time is less than the preset time limit, then the target prediction time is increased by the preset step size and the iteration continues. If the target candidate point fails to pass the forward flyable sector determination and the target prediction time reaches the preset time limit, the iteration stops, and the original theoretical target point calculated based on the lead aircraft's current position and current heading angle is used as the target update point.

6. The method of claim 1, wherein, The step of calculating the target airspeed based on the state information, the longitudinal error of the target update point projected along the heading angle of the lead aircraft, and the feedforward wind speed component includes: Obtain the environmental wind speed vector, project the environmental wind speed vector onto the lead aircraft's ground-to-ground heading, and obtain the feedforward wind speed component; The difference vector relative to the target update point is projected onto the lead aircraft's ground heading to obtain the longitudinal error, wherein a positive longitudinal error indicates that the wingman is ahead of the target update point, and a negative longitudinal error indicates that the wingman is behind the target update point; The target airspeed is calculated based on the lead aircraft's ground speed, the feedforward wind speed component, the preset longitudinal proportional gain, and the longitudinal error in the status information. When the longitudinal error is greater than the negative preset deceleration margin, the target airspeed is set to the preset minimum cruise airspeed; the target airspeed is limited between the preset minimum cruise airspeed and the preset maximum cruise airspeed.

7. The method as described in claim 1, characterized in that, The compound-wing UAV formation cooperative control method further includes: Get the preset backoff distance; Based on the lead aircraft's ground heading angle, the target update point, and the preset backtracking distance in the status information, a virtual previous waypoint is determined in the opposite direction of the lead aircraft's ground heading. The target update point is used as the current waypoint, the virtual previous waypoint is used as the previous waypoint, and guidance input is provided to the fixed-wing position controller in combination with the target airspeed. Guide the wingman to approach the target update point along the lead aircraft's ground heading angle.

8. A composite-wing unmanned aerial vehicle (UAV) formation cooperative control device, characterized in that, The device includes: The receiving module is used to receive status information and formation switching instructions broadcast by the primary aircraft. The determination module is used to determine the offset vector relative to the lead aircraft based on the formation geometry configuration corresponding to the formation switching instruction; The conversion module is used to convert the offset vector into a theoretical target point based on the current position of the lead aircraft and the lead aircraft's heading angle to the ground in the status information. The update module is used to iteratively update the current position of the lead aircraft and the heading angle of the lead aircraft to the ground in the status information based on the judgment result that the theoretical target point is located in the preset forward flyable sector, until the preset termination condition is met, and the target update point is obtained. The calculation module is used to obtain the feedforward wind speed component and calculate the target airspeed based on the state information, the longitudinal error of the target update point projected along the heading angle of the lead aircraft, and the feedforward wind speed component. The execution module is used to set the target airspeed to a preset minimum cruise airspeed and limit the target airspeed between the preset minimum cruise airspeed and the preset maximum cruise airspeed when the longitudinal error is greater than a negative preset deceleration margin, and to generate the airspeed setting value of the wingman during formation switching based on the limited target airspeed.

9. A composite-wing unmanned aerial vehicle (UAV) formation coordination control device, characterized in that, The device includes: a memory, a processor, and a computer program stored in the memory and executable on the processor, the computer program being configured to implement the steps of the compound-wing UAV formation cooperative control method as described in any one of claims 1 to 7.

10. A storage medium, characterized in that, The storage medium is a computer-readable storage medium, and a computer program is stored on the storage medium. When the computer program is executed by a processor, it implements the steps of the compound-wing UAV formation cooperative control method as described in any one of claims 1 to 7.

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