A formation control method, device, equipment and storage medium for a distributed vertical take-off and fixed-wing UAV cluster

Abstract

An embodiment of this specification discloses a formation control method, device, equipment, and storage medium for a distributed vertical takeoff fixed-wing UAV cluster, which relates to the technical field of UAV formation control. The method includes: receiving topological position information of the formation, and determining a planned path; determining a first flight speed according to the current position information and the expected position information in the planned path; determining a second flight speed according to the current position information, the expected position information, and the topological position information in the formation; determining a third flight speed according to the current position information and the positional relationship with other UAVs in the formation; calculating a target flight speed based on the first flight speed, the second flight speed, and the third flight speed; and controlling the formation according to the target flight speed, effectively ensuring the stability and safety of the formation of the vertical takeoff fixed-wing UAV cluster.

Description

Technical Field

[0001] The present application relates to the technical field of UAV formation control, and in particular, to a formation control method, device, equipment and storage medium for a distributed vertical take-off and fixed-wing UAV cluster. Background Art

[0002] The vertical take-off and fixed-wing UAV can take off and land within a small range, and has the ability of fixed-point hovering, which can perform fixed-point monitoring of target points and long endurance.

[0003] Currently, when multiple vertical take-off and fixed-wing UAV clusters perform flight missions, the formation will be disrupted and the UAVs will collide with each other, resulting in the inability to ensure the formation.

[0004] Therefore, how to ensure the stability and safety of the formation of multiple vertical take-off and fixed-wing UAVs has become an urgent technical problem to be solved. Summary of the Invention

[0005] The embodiments of the present specification provide a formation control method for a distributed vertical take-off and fixed-wing UAV cluster to solve the problem in the prior art that the stability and safety of the formation of multiple vertical take-off and fixed-wing UAVs cannot be ensured.

[0006] To solve the above technical problems, the embodiments of the present specification are implemented as follows:

[0007] In a first aspect, a formation control method for a distributed vertical take-off and fixed-wing UAV cluster provided by the embodiments of the present specification is applied to any UAV in the vertical take-off and fixed-wing UAV cluster, and includes:

[0008] Receiving the topological position information of the formation, and determining the planned path;

[0009] Determining a first flight speed according to the current position information and the expected position information in the planned path;

[0010] Determining a second flight speed according to the current position information, the expected position information and the topological position information in the formation;

[0011] Determining a third flight speed according to the current position information and the position relationship with other UAVs in the formation;

[0012] Calculating a target flight speed based on the first flight speed, the second flight speed and the third flight speed;

[0013] Controlling the formation according to the target flight speed.

[0014] Second aspect, a formation control device for a distributed vertical takeoff and fixed-wing UAV cluster provided by an embodiment of this specification is applied to any UAV in the vertical takeoff and fixed-wing UAV cluster, and includes:

[0015] A planned path determination module, configured to receive topological position information of the formation, and determine a planned path;

[0016] A first flight speed determination module, configured to determine a first flight speed according to the current position information and the expected position information in the planned path;

[0017] A second flight speed determination module, configured to determine a second flight speed according to the current position information, the expected position information, and the topological position information in the formation;

[0018] A third flight speed determination module, configured to determine a third flight speed according to the current position information and the position relationship with other UAVs in the formation;

[0019] A target flight speed determination module, configured to calculate a target flight speed based on the first flight speed, the second flight speed, and the third flight speed;

[0020] A control module, configured to control the formation according to the target flight speed.

[0021] Third aspect, a formation control device for a distributed vertical takeoff and fixed-wing UAV cluster provided by an embodiment of this specification includes a memory, a processor, and a computer program stored on the memory. The processor executes the computer program to implement the formation control method for the distributed vertical takeoff and fixed-wing UAV cluster in Solution 1.

[0022] Fourth aspect, a computer-readable storage medium provided by an embodiment of this specification has a computer program stored thereon. When the computer program is executed by a processor, it implements the formation control method for the distributed vertical takeoff and fixed-wing UAV cluster in Solution 1.

[0023] An embodiment of this specification achieves the following beneficial effects: By calculating the target flight speed of each vertical takeoff and fixed-wing UAV through the first flight speed that conforms to the planned path, the second flight speed for controlling the formation, and the third flight speed for preventing collisions, and adopting a method that comprehensively considers the path planning control speed, the formation control speed, and the anti-collision control speed, the stability and safety of the formation of the vertical takeoff and fixed-wing UAV cluster are effectively guaranteed. Description of the Drawings

[0024] To more clearly illustrate the technical solutions in the embodiments of this specification or the prior art, the following will briefly introduce the drawings required for use in the description of the embodiments or the prior art. Obviously, the drawings in the following description are only some embodiments recorded in this application. For those of ordinary skill in the art, without creative efforts, other drawings can also be obtained based on these drawings.

[0025] Figure 1 Schematic flowchart of a formation control method for a distributed vertical take-off fixed-wing UAV cluster provided by an embodiment of this specification;

[0026] Figure 2 Schematic diagram of the virtual center planned path trajectory provided by an embodiment of this specification;

[0027] Figure 3 Schematic diagram of the planned path for three vertical take-off fixed-wing UAVs to perform tasks in a triangular formation provided by an embodiment of this specification;

[0028] Figure 4 Schematic diagram of the impulse function for UAV anti-collision provided by an embodiment of this specification;

[0029] Figure 5 Schematic diagram of an application scenario of a formation control method for a distributed vertical take-off fixed-wing UAV cluster provided by an embodiment of this specification;

[0030] Figure 6 Schematic diagram of an application scenario of a formation control method for three vertical take-off fixed-wing UAVs provided by an embodiment of this specification;

[0031] Figure 7 Schematic diagram of the formation error curve between every two vertical take-off fixed-wing UAVs provided by an embodiment of this specification;

[0032] Figure 8 Schematic diagram of another application scenario of a formation control method for three vertical take-off fixed-wing UAVs provided by an embodiment of this specification;

[0033] Figure 9 Schematic diagram of the relative distance curve between every two vertical take-off fixed-wing UAVs provided by an embodiment of this specification;

[0034] Figure 10 Schematic diagram of the structure of a formation control device for a distributed vertical take-off fixed-wing UAV cluster provided by an embodiment of this specification;

[0035] Figure 11 Schematic diagram of the structure of a formation control device for a distributed vertical take-off fixed-wing UAV cluster provided by an embodiment of this specification. Detailed implementation manners

[0036] To make the objectives, technical solutions, and advantages of one or more embodiments of this specification clearer, the following will clearly and completely describe the technical solutions of one or more embodiments of this specification in conjunction with the specific embodiments of this specification and the corresponding drawings. Obviously, the described embodiments are only a part of the embodiments of this specification, rather than all the embodiments. Based on the embodiments in this specification, all other embodiments obtained by those of ordinary skill in the art without creative efforts fall within the scope protected by one or more embodiments of this specification.

[0037] The following will, in conjunction with the drawings, detail the technical solutions provided by each embodiment of this specification.

[0038] A specific description will be given of the formation control method for a distributed vertical takeoff and fixed-wing UAV cluster provided in the embodiments of the specification in conjunction with the drawings.

[0039] Figure 1 This is a schematic flowchart of a formation control method for a distributed vertical takeoff and fixed-wing UAV cluster provided in the embodiments of this specification. From a program perspective, the execution subject of the process can be a program or an application client installed on an application server. On the other hand, from a hardware perspective, the execution subject of the process can be a terminal device, and the execution subject can be installed on a UAV.

[0040] As Figure 1 shown, applied to any UAV in a vertical takeoff and fixed-wing UAV cluster, this process may include the following steps:

[0041] Step 110: Receive the topological position information of the formation and determine the planned path.

[0042] In the embodiments of this specification, when a UAV is performing a flight mission, in order to effectively cover the entire reconnaissance area, multiple UAVs need to fly in accordance with a set formation.

[0043] Based on the spatial arrangement formed by UAV individuals during formation flight, clarify the position of each individual and the relative position relationship between them, and plan an optimal path for each UAV from the current position to the target position.

[0044] Step 120: Determine the first flight speed according to the current position information and the expected position information in the planned path.

[0045] In the embodiments of this specification, the current position information may include the current coordinates (longitude, latitude, altitude, etc.), speed, attitude, etc. of the UAV, and the expected position information may be the position information of the next or a series of target points that the UAV needs to reach in the planned path.

[0046] The first flight speed vector v 1,i = k1(p i,d - p i ), where p i is the current position, p i,d is the desired position, and k1 is a control parameter. The first flight speed is used to adjust the attitude or thrust of the UAV to achieve stable flight along the planned path.

[0047] In practical applications, the position information of the UAV can be obtained through sensors such as radar, lidar, and cameras.

[0048] Step 130: Determine the second flight speed according to the current position information, the desired position information, and the topological position information in the formation.

[0049] In the embodiments of this specification, based on the current position information and the desired position information, a basic flight speed is initially calculated, and the flight speed is adjusted according to the topological position information in the formation to maintain the formation. For example, if the UAV is at the front of the formation, it may need to fly slightly faster to lead other UAVs; if it is at the rear, it may need to slow down to keep the relative position unchanged.

[0050] The second flight speed can ensure the relative position of the UAV in the formation and maintain the formation.

[0051] In practical applications, during flight, the flight speed is dynamically adjusted according to the real-time position information and the formation state to ensure the coordinated flight of the UAVs. When adjusting the flight speed, the positions and speeds of other UAVs are considered to maintain the stability and consistency of the formation.

[0052] Step 140: Determine the third flight speed according to the current position information and the position relationship with other UAVs in the formation.

[0053] In the embodiments of this specification, it is necessary to comprehensively consider the current position information of the UAV and the position relationship with other UAVs in the formation to ensure that the UAV avoids collisions with other UAVs or obstacles while maintaining the formation.

[0054] The third flight speed can ensure the safety during flight and avoid collisions with other UAVs.

[0055] When adjusting the flight speed, the performance limitations of the UAV, such as the maximum speed and acceleration ability, also need to be considered to ensure that the UAV can fly stably and safely.

[0056] Step 150: Calculate the target flight speed based on the first flight speed, the second flight speed, and the third flight speed.

[0057] Step 160: Control the formation flight pattern according to the target flight speed.

[0058] In the embodiments of this specification, by comprehensively considering the first flight speed, the second flight speed, and the third flight speed, it is ensured that the flight process not only meets the requirements of the planned path and formation flight pattern but also avoids collisions, guaranteeing the safety objective of flight. The target flight speed comprehensively considers multiple factors, ensuring that the flight process is both safe and efficient.

[0059] During the flight process, parameters such as the position, speed, and heading of the UAV can be monitored in real time, as well as the stability of the formation flight pattern. According to the real-time monitored data and the changes in the target flight speed, the control parameters of the UAV are dynamically adjusted to maintain the stability and consistency of the formation flight pattern. Effectively control the formation flight pattern according to the target flight speed to ensure the safety and stability of the flight process.

[0060] It should be understood that the order of some steps in the method described in one or more embodiments of this specification can be mutually exchanged according to actual needs, or some of the steps can also be omitted or deleted.

[0061] In the embodiments of this specification, the target flight speed of each vertical takeoff and fixed-wing UAV is calculated through the first flight speed that conforms to the planned path, the second flight speed that controls the formation flight pattern, and the third flight speed that prevents collisions. By comprehensively considering the path planning control speed, the formation flight pattern control speed, and the anti-collision control speed, the stability and safety of the formation flight pattern of the vertical takeoff and fixed-wing UAV cluster are effectively guaranteed. At the same time, unified control and scheduling of the UAVs can also be achieved, improving the adaptability and efficiency of formation flight.

[0062] Based on Figure 1 the method in, the embodiments of this specification also provide some specific implementation schemes of this method, which will be described below.

[0063] Optionally, in the embodiments of this specification, the receiving of the topological position information of the formation flight pattern and the determination of the planned path may specifically include:

[0064] Receive the waypoint position information within the preset flight range, and based on the path planning algorithm, obtain the virtual center planned path;

[0065] According to the topological position information in the formation flight pattern, determine the position difference information from the virtual center planned path;

[0066] According to the position difference information, based on the path planning algorithm, obtain the planned path.

[0067] Figure 2 Schematic diagram of the virtual center planned path trajectory provided by the embodiments of this specification.

[0068] In the embodiments of this specification, according to the task requirements, the waypoint information passed by the vertical takeoff and fixed-wing UAV during the mission is obtained. For example, the waypoint information is P0, P1, P2, …, P n , and the path planning algorithm can be a B-spline curve. As Figure 2 shown, taking the waypoint P i (i = 0, 1, …, n) as the control points of the B-spline curve basis function, a smooth virtual center path with continuous curvature can be generated as the virtual center planned path. The basis function of the third-order spline curve is:

[0069] where u is the control parameter, and N i,3 (u) is the basis function of the i-th third-order B-spline curve, corresponding to the control point P i .

[0070] The third-order B-spline curve segment P i to P i+3 is expressed as: i,i+3 P

[0071] P i,i+3 (u) = P i N 0,3 (u) + P i+1 N 1,3 (u) + P i+2 N 2,3 (u) + P i+3 N 3,3 (u).

[0072] Figure 3 Schematic diagram of the planned path for three vertical takeoff and fixed-wing UAVs to perform tasks in a triangular formation provided by the embodiments of this specification.

[0073] As Figure 3 shown, the position difference information of each UAV relative to the virtual center planned path is obtained, and the relative position difference vector is mapped to the ground coordinate system. Then, the B-spline curve is used again to plan a smooth single UAV trajectory for each UAV.

[0074] Specifically, the position difference information δ i = [δ i,x δ i,y T of each UAV relative to the virtual center planned path is obtained, where T is the transpose of the matrix.

[0075] ​Map the position difference vector to the ground coordinate system for comparison and adjustment with the position information of the UAV. The heading angle θ(t) of the virtual center's planned path is

[0076] θ(t) = atan2(P c,y (t), P c,x (t)), where P c (t) = [x c (t + 1) - x c (t) y c (t + 1) - y c (t)] T is the position change vector of the virtual center's planned path at time t, and P c,x (t) and P c,y (t) are the components of P c (t) in the two-dimensional plane respectively. The rotation matrix is used to transform the relative position vector with respect to the formation center trajectory into the ground coordinate system.

[0077] The construction of the rotation matrix is as follows:

[0078] Through the rotation matrix obtain the transformed position vector where δ i,x and δ i,y are the components of δ i in the two-dimensional plane respectively, is the rotation matrix.

[0079] Use the cubic B-spline curve again with δ i as the control point of the trajectory of each vertical takeoff fixed-wing UAV to generate a smooth trajectory curve to ensure that each UAV flies along a smooth path.

[0080] Optionally, in the embodiments of this specification, determining the second flight speed according to the current position information, the desired position information, and the topological position information in the formation may specifically include:

[0081] Determine the actual relative position information according to the current position information and the current position information of other UAVs in the formation;

[0082] Determine the desired relative position information according to the desired position information, the desired position information of other UAVs in the formation, and the topological position information in the formation;

[0083] Determine the second flight speed based on the actual relative position information and the desired relative position information according to the consensus protocol.

[0084] In the embodiments of this specification, the formation control speed is designed for each drone through the consensus theory.

[0085] Specifically, also based on the heading angle of the path planned by the virtual center, the rotation matrix is calculated. The function of the rotation matrix is to convert the desired position error vector to the ground coordinate system, and the transformed position vector is obtained through the rotation matrix.

[0086] For example, the actual relative position vector between the i-th drone and the j-th drone is and the desired relative position vector is Then where p i is the actual position vector of the i-th drone; p j is the actual position vector of the j-th drone; is the desired position vector of the i-th drone; is the desired position vector of the j-th drone; is the rotation matrix, which is used to convert the relative position vector with respect to the path planned by the virtual center to the body coordinate system of the drone.

[0087] Based on the consensus protocol, the second flight speed vector is calculated. For each drone i, the vector difference between its actual relative position and the desired relative position with other drones is calculated and accumulated into v 2,i . The second flight speed vector v 2,i , can be expressed as: where k2 is the proportionality coefficient, N is the number of drones in the formation, is the vector difference between the actual relative position and the desired relative position of the i-th drone with respect to other drones j.

[0088] Optionally, in the embodiments of this specification, determining the third flight speed according to the current position information and the position relationship with other drones in the formation may specifically include:

[0089] Determine the relative distance between two adjacent drones according to the current position information, the current position information of other drones in the formation, and the position relationship with other drones in the formation;

[0090] Based on the relative distance and the obstacle function, determine the third flight speed.

[0091] In the embodiments of this specification, it is necessary to comprehensively consider the position information of the current drone, the current position information of other drones in the formation, and their position relationship to determine the third flight speed.

[0092] Adjacent can mean that there are no other drones between two drones. The obstacle function is a distance-related function used to quantify the proximity between a drone and other drones. Use GPS or other positioning technologies to obtain the precise position information of the current drone, and at the same time obtain the current position information of all other drones in the formation. According to the design of the formation, determine the adjacent drones of the current drone in the formation. Use the relative distance and the obstacle function to calculate the obstacle value between the current drone and each adjacent drone, and adjust the speed of the drone.

[0093] Further, optionally, in the embodiments of this specification, the preset anti-collision threshold includes a danger threshold and a safety threshold, and the danger threshold is less than the safety threshold. Determining the third flight speed according to the relative distance based on the obstacle function may specifically include:

[0094] Compare the relative distance with the danger threshold and the safety threshold to determine the impulse function;

[0095] Based on the impulse function and the obstacle function, determine the third flight speed.

[0096] In the embodiments of this specification, the preset anti-collision threshold may be the minimum safety distance preset according to factors such as the performance of the drone, the flight environment, and safety standards, and is used to determine whether the drone is at a potential collision risk.

[0097] Based on the obstacle function, avoid the collision between the i-th drone and the j-th drone, and prevent the third flight speed vector of the drone collision Among them, k3 is a proportionality coefficient, and σ is a continuously differentiable impulse function, which can be expressed as

[0098]

[0099] d1 is the danger threshold, d2 is the safety threshold, and x is the relative distance between two adjacent drones.

[0100] Figure 4 It is a schematic diagram of the impulse function for drone anti-collision provided by the embodiments of this specification. As Figure 4 shown, when the relative distance between two adjacent drones is less than the danger threshold d1, the value of the impulse function is 1, indicating that the distance is too close and coercive measures need to be taken to avoid collision; when the relative distance exceeds the safety threshold d2, the value of the impulse function is 0, indicating that the distance is far enough and no additional measures are required; when the relative distance is between d1 and d2, the impulse function adopts a piecewise polynomial form to ensure the continuity and smoothness of the impulse function in this interval.

[0101] Optionally, calculating the target flight speed based on the first flight speed, the second flight speed, and the third flight speed in the embodiments of this specification may specifically include:

[0102] Comparing the second flight speed with the formation control speed threshold to determine the second target flight speed;

[0103] Comparing the third flight speed with the anti-collision control speed threshold to determine the third target flight speed;

[0104] Calculating the target flight speed based on the first flight speed, the second target flight speed, and the third target flight speed.

[0105] In the embodiments of this specification, the target flight speed u is composed of the first flight speed (trajectory control amount) v 1,i , the second flight speed (formation control amount) v 2,i , and the third flight speed (anti-collision control amount) v 3,i . The target flight speed u = v 1,i + sat(sat(v 2,i , v a,i ) + v 3,i , v b,i ), where

[0106]

[0107] where v a,i is the formation control threshold of the i-th unmanned aerial vehicle, v a,i > 0, v b,i is the anti-collision control speed threshold of the i-th unmanned aerial vehicle, v b,i > 0, after saturation, ||v 2,i || ≤ v a,i , ||sat(v 2,i , v a,i ) + v 3,i || ≤ v b,i always holds, and this saturation function does not change the direction of the vector, only restricting the magnitude of the vector two-norm.

[0108] Optionally, controlling the formation according to the target flight speed in the embodiments of this specification may specifically include:

[0109] Calculating the unit vector of the target flight speed to obtain the current flight speed;

[0110] Calculating the flight speed at the previous moment according to the current yaw angle information;

[0111] Calculate the yaw angle at the next moment according to the current flight speed and the flight speed at the previous moment;

[0112] Control the formation according to the target flight speed and the yaw angle at the next moment.

[0113] In the embodiments of this specification, the current flight speed vector v is calculated from the target flight speed u now = u / ||u||, and the yaw angle ψ of the UAV at the current moment is obtained n , and the flight speed vector v of the UAV at the previous moment is calculated last = [cos(ψ) sin(ψ)] T , and the yaw angle at the next moment is calculated according to the current flight speed and the flight speed at the previous moment. The yaw angle ψ at the next moment d can be expressed as:

[0114] ψ d = ψ n + Δψ d , where Δψ d is the yaw angle control increment, and v last × v now represents the cross product of two vectors.

[0115] In practical applications, according to the formation kinematic relationship, the kinematic model of the UAV during formation flight can be expressed as: where, is the first derivative of x i , is the first derivative of y i , is the first derivative of ψ i , [x i y i T is the position information of the UAV, v i is the flight speed information of the UAV, ψ i is the yaw angle of the UAV, and w i represents the yaw angular velocity of the UAV. Considering the safety issues of the vertical takeoff and fixed-wing UAV, the following limiting conditions need to be set for the flight speed and yaw angular velocity of the UAV: where v min,i is the minimum flight speed, v max,i is the maximum flight speed, and w max,i is the maximum yaw angular velocity.

[0116] Figure 5 This is a schematic diagram of an application scenario of a formation control method for a distributed vertical takeoff and fixed-wing UAV swarm provided by the embodiments of this specification. ​

[0117] In practical applications, when a drone executes a flight mission, such as Figure 5 shown, input the mission plan (waypoint information, topological position information, preset anti-collision threshold, formation ID, etc.) and limiting factors (flight speed limit, yaw angular velocity limit) into the drone.

[0118] Step 501: Obtain waypoint position information;

[0119] Step 502: Generate a virtual center planned path and a planned path for each drone;

[0120] Step 503: Determine whether the drone is flying along the planned path. If so, execute Step 504. If not, adjust the drone according to the first flight speed, and then execute Step 504 after adjustment;

[0121] Step 504: Determine whether the drone is flying in the formation. If so, execute Step 505. If not, adjust the drone according to the second flight speed, and then execute Step 505 after adjustment;

[0122] Step 505: Determine whether the relative distance between two adjacent drones is less than the danger threshold. If so, execute Step 506. If not, adjust the drone according to the third flight speed, and then execute Step 506 after adjustment;

[0123] Step 506: Determine whether the drone has reached the last waypoint. If so, execute Step 507. If not, return to execute Step 503;

[0124] Step 507: End the mission.

[0125] In practical applications, each drone in the formation can cooperate to process tasks on different computing nodes, realize information sharing and synchronization status, so as to better adapt to complex and changeable environments and mission requirements, and improve the robustness and scalability of the system.

[0126] Figure 6 It is a schematic diagram of an application scenario of the formation control method for three vertical takeoff and fixed-wing drones provided in the embodiments of this specification.

[0127] In practical applications, such as Figure 6 shown, in the initial state, three vertical takeoff and fixed-wing drones form a triangular formation and fly along the "L" - shaped route, and set the initial waypoint P i(i = 1, 2, …, 5) is [0, 0], [0, 100], [100, 100], [200, 100], [300, 100]. According to the waypoint position information, a smooth virtual center planned path can be obtained using a B-spline curve. The position difference vectors of the three UAVs (UAV No. 1, UAV No. 2, UAV No. 3) relative to the virtual center planned path are: [30, 0], [0, -30], [0, 30]. By using the position difference vectors, the planned path of each UAV can be obtained. By setting the control parameters k1 = 1, k2 = 3, k3 = 100, the target flight speed of the UAVs can be obtained.

[0128] During the flight, at the turning point of the flight path, due to the length difference between the inner and outer trajectories, the formation will be disrupted. According to the target flight speed, the UAVs can still maintain the formation within a certain period of time after the formation reconstruction at the turning point.

[0129] Figure 7 It is a schematic diagram of the formation error curve between every two vertical takeoff and fixed-wing UAVs provided by the embodiments of this specification. From Figure 7 it can be seen that when the formation of the three UAVs is disrupted at the turning point, the UAVs can quickly restore the expected formation and keep the error between the actual distance and the expected distance of the formation within a very small range.

[0130] Figure 8 It is a schematic diagram of another application scenario of the formation control method for three vertical takeoff and fixed-wing UAVs provided by the embodiments of this specification.

[0131] In practical applications, three vertical takeoff and fixed-wing UAVs fly in a "one" formation. The relative distance between every two UAVs is d = 12 m. The dangerous threshold d1 = 15 m and the safety threshold d2 = 20 m are set. As Figure 8 shown, when the relative distance between the UAVs is less than d1, if there is no intervention by the anti-collision algorithm, they will always maintain the distance d between the aircraft. At this time, the distance between the UAVs is too close, which will increase the collision risk.

[0132] According to the target flight speed, the relative distance between every two UAVs will be maintained between d1 and d2.

[0133] Figure 9 It is a schematic diagram of the relative distance curve between every two vertical takeoff and fixed-wing UAVs provided by the embodiments of this specification.

[0134] From Figure 9It can be seen that although the relative distance between UAV No. 1 and UAV No. 2 is set to 12 m, due to the intervention of the obstacle function, the actual distance between the two UAVs still remains at about the expected distance threshold of 20 m; the same is true for UAV No. 2 and UAV No. 3; while the relative distance between UAV No. 1 and UAV No. 3 is greater than the safety threshold d2, so they fly in the expected formation.

[0135] Figure 10 FIG. is a schematic structural diagram of a formation control device for a distributed vertical takeoff and fixed-wing UAV cluster proposed in an embodiment of this specification.

[0136] Corresponding to the foregoing method embodiment, the formation control device for a distributed vertical takeoff and fixed-wing UAV cluster recorded in the embodiment of this specification may include:

[0137] A planned path determination module 1002, configured to receive topological position information of a formation and determine a planned path;

[0138] A first flight speed determination module 1004, configured to determine a first flight speed according to current position information and expected position information in the planned path;

[0139] A second flight speed determination module 1006, configured to determine a second flight speed according to the current position information, the expected position information, and topological position information in the formation;

[0140] A third flight speed determination module 1008, configured to determine a third flight speed according to the current position information and the positional relationship with other UAVs in the formation;

[0141] A target flight speed determination module 1010, configured to calculate a target flight speed based on the first flight speed, the second flight speed, and the third flight speed;

[0142] A control module 1012, configured to control the formation according to the target flight speed.

[0143] In the embodiment of this specification, the target flight speed of each vertical takeoff and fixed-wing UAV is calculated through the first flight speed that conforms to the planned path, the second flight speed for controlling the formation, and the third flight speed for preventing collisions. By comprehensively considering the path planning control speed, the formation control speed, and the anti-collision control speed, the stability and safety of the formation of the vertical takeoff and fixed-wing UAV cluster are effectively guaranteed. At the same time, unified control and scheduling of the UAVs can also be realized, improving the adaptability and efficiency of formation flight.

[0144] Based on the same idea as the foregoing method embodiment, the embodiment of this specification also provides a device corresponding to the above method.

[0145] Figure 11 This is a schematic structural diagram of a formation control device for a distributed vertical takeoff and fixed-wing UAV cluster provided in the embodiments of this specification. As Figure 11 shown, a formation control device for a distributed vertical takeoff and fixed-wing UAV cluster provided in the embodiments of this specification includes a memory 1130, a processor 1110, and a computer program 1120 stored on the memory. The processor 1110 executes the computer program 1120 to implement the formation control method for the distributed vertical takeoff and fixed-wing UAV cluster described in any of the above embodiments.

[0146] A formation control device for a distributed vertical takeoff and fixed-wing UAV cluster provided in the embodiments of this specification may include a memory, a processor, and a computer program stored on the memory. The processor executes the computer program to implement the formation control method for the distributed vertical takeoff and fixed-wing UAV cluster described in any of the above embodiments.

[0147] A computer-readable storage medium provided in the embodiments of this specification has a computer program stored thereon. When the computer program is executed by a processor, it can implement the formation control method for the distributed vertical takeoff and fixed-wing UAV cluster described in any of the above embodiments.

[0148] Each embodiment in this specification is described in a progressive manner. The same or similar parts among the embodiments can be referred to each other, and the differences between each embodiment and other embodiments are emphasized. In particular, for Figure 11 the device shown, since it is basically similar to the method embodiment, the description is relatively simple, and the relevant parts can be referred to the partial description of the method embodiment.

[0149] In the 1990s, improvements to a technology could be clearly distinguished as either hardware improvements (e.g., improvements to circuit structures such as diodes, transistors, switches, etc.) or software improvements (improvements to method flows). However, with the development of technology, many method flow improvements today can be regarded as direct improvements to hardware circuit structures. Almost all designers obtain the corresponding hardware circuit structure by programming the improved method flow into the hardware circuit. Therefore, it cannot be said that an improvement to a method flow cannot be implemented using a hardware entity module. For example, a Programmable Logic Device (PLD) (e.g., a Field Programmable Gate Array (FPGA)) is such an integrated circuit whose logical function is determined by the user programming the device. The designer programs it himself to "integrate" a digital system on a single PLD, without having to ask a chip manufacturer to design and fabricate a dedicated integrated circuit chip. Moreover, nowadays, instead of manually fabricating integrated circuit chips, this programming is mostly implemented using "logic compiler" software, which is similar to the software compiler used in program development and writing. The original code before compilation also has to be written in a specific programming language, which is called a Hardware Description Language (HDL). There is not just one type of HDL, but many, such as ABEL (Advanced Boolean Expression Language), AHDL (Altera Hardware Description Language), Confluence, CUPL (Cornell University Programming Language), HDCal, JHDL (Java Hardware Description Language), Lava, Lola, MyHDL, PALASM, RHDL (Ruby Hardware Description Language), etc. The most commonly used ones currently are VHDL (Very-High-Speed Integrated Circuit Hardware Description Language) and Verilog. Those skilled in the art should also be aware that by simply performing a little logical programming on the method flow using the above-mentioned several hardware description languages and programming it into the integrated circuit, it is easy to obtain the hardware circuit that implements the logical method flow.

[0150] The controller can be implemented in any suitable manner. For example, the controller can take the form of, for example, a microprocessor or a processor and a computer-readable medium storing computer-readable program code (such as software or firmware) executable by the (micro)processor, logic gates, switches, an application specific integrated circuit (ASIC), a programmable logic controller, and an embedded microcontroller. Examples of the controller include, but are not limited to, the following microcontrollers: ARC 625D, Atmel AT91SAM, Microchip PIC18F26K20, and Silicone Labs C8051F320. The memory controller can also be implemented as part of the control logic of the memory. Those skilled in the art also know that, in addition to implementing the controller in the form of pure computer-readable program code, it is entirely possible to make the controller implement the same function in the form of logic gates, switches, application specific integrated circuits, programmable logic controllers, and embedded microcontrollers by logically programming the method steps. Therefore, such a controller can be considered a hardware component, and the devices included therein for implementing various functions can also be regarded as the structures within the hardware component. Or even, the devices for implementing various functions can be regarded as either software modules for implementing the method or structures within the hardware component.

[0151] The systems, devices, modules, or units illustrated in the above embodiments can be specifically implemented by computer chips or entities, or by products with certain functions. A typical implementation device is a computer. Specifically, the computer can be, for example, a personal computer, a laptop computer, a cellular phone, a camera phone, a smart phone, a personal digital assistant, a media player, a navigation device, an email device, a game console, a tablet computer, a wearable device, or a combination of any of these devices.

[0152] For the convenience of description, when describing the above devices, they are described separately as various units according to their functions. Of course, when implementing the present application, the functions of each unit can be implemented in the same or multiple software and / or hardware.

[0153] Those skilled in the art should understand that the embodiments of the present invention can be provided as a method, a system, or a computer program product. Therefore, the present invention can take the form of a completely hardware embodiment, a completely software embodiment, or an embodiment combining software and hardware aspects. Moreover, the present invention can take the form of a computer program product implemented on one or more computer-usable storage media (including but not limited to disk memories, CD-ROMs, optical memories, etc.) containing computer-usable program code.

[0154] The present invention is described with reference to flowchart illustrations and / or block diagrams of methods, apparatus (systems), and computer program products according to embodiments of the invention. It should be understood that each flow and / or block of the flowchart illustrations and / or block diagrams, and combinations of flows and / or blocks in the flowchart illustrations and / or block diagrams, can be implemented by computer program instructions. These computer program instructions may be provided to the processors of a general purpose computer, special purpose computer, embedded processor, or other programmable data processing device to produce a machine, such that the instructions executed by the processors of the computer or other programmable data processing device create means for implementing the functions specified in the flowchart Figure 1 for one or more flows and / or blocks Figure 1 for one or more blocks.

[0155] These computer program instructions may also be stored in a computer-readable memory that can direct a computer or other programmable data processing device to function in a particular manner, such that the instructions stored in the computer-readable memory produce an article of manufacture including instruction means that implement the functions specified in the flowchart Figure 1 for one or more flows and / or blocks Figure 1 for one or more blocks.

[0156] These computer program instructions may also be loaded onto a computer or other programmable data processing device, such that a series of operational steps are performed on the computer or other programmable device to produce a computer-implemented process, and thus the instructions executed on the computer or other programmable device provide steps for implementing the functions specified in the flowchart Figure 1 for one or more flows and / or blocks Figure 1 for one or more blocks.

[0157] In a typical configuration, a computing device includes one or more processors (CPUs), an input / output interface, a network interface, and memory.

[0158] The memory may include non-permanent memory in the form of computer-readable media, random access memory (RAM), and / or non-volatile memory, such as read-only memory (ROM) or flash memory (flash RAM). The memory is an example of computer-readable media.

[0159] Computer readable media include permanent and non-permanent, removable and non-removable media that can be implemented by any method or technology to store information. Information can be computer readable instructions, data structures, program modules or other data. Examples of computer storage media include, but are not limited to, phase change memory (PRAM), static random access memory (SRAM), dynamic random access memory (DRAM), other types of random access memory (RAM), read-only memory (ROM), electrically erasable programmable read-only memory (EEPROM), flash memory or other memory technology, compact disk read-only memory (CD-ROM), digital versatile disk (DVD) or other optical storage, magnetic cassettes, magnetic tape disk storage or other magnetic storage devices or any other non-transmission media that can be used to store information that can be accessed by a computing device. As defined herein, computer readable media does not include temporary computer readable media (transitory media), such as modulated data signals and carrier waves.

[0160] It should also be noted that the terms "include", "comprises" or any other variations thereof are intended to cover non-exclusive inclusion, so that a process, method, commodity or device including a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such process, method, commodity or device. In the absence of more restrictions, the elements defined by the sentence "comprises a ..." do not exclude the existence of other identical elements in the process, method, commodity or device including the elements.

[0161] Those skilled in the art will appreciate that the embodiments of the present application may be provided as methods, systems or computer program products. Therefore, the present application may adopt the form of a complete hardware embodiment, a complete software embodiment or an embodiment in combination with software and hardware. Moreover, the present application may adopt the form of a computer program product implemented on one or more computer-usable storage media (including but not limited to disk storage, CD-ROM, optical storage, etc.) that contain computer-usable program code.

[0162] The present application may be described in the general context of computer-executable instructions executed by a computer, such as program modules. Generally, program modules include routines, programs, objects, components, data structures, etc. that perform specific tasks or implement specific abstract data types. The present application may also be practiced in distributed computing environments where tasks are performed by remote processing devices connected through a communication network. In a distributed computing environment, program modules may be located in local and remote computer storage media, including storage devices.

[0163] The above are only embodiments of the present application and are not intended to limit the present application. For those skilled in the art, various changes and modifications can be made to the present application. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present application shall be included within the scope of the claims of the present application.

Claims

1. A formation control method for a distributed vertical take-off fixed-wing UAV cluster, characterized in that: Applied to any UAV in a vertical take-off fixed-wing UAV cluster, the method comprises: Receive the topological position information of the formation and determine the planned path; determining a first flight speed according to current position information and expected position information in the planned path; determining a second flight speed according to the current position information, the expected position information, and the topological position information in the formation; Determining a third flight speed according to the current position information and a positional relationship with other UAVs in the formation; calculating a target flight speed based on the first flight speed, the second flight speed, and the third flight speed; Controlling the formation according to the target flight speed; The determining of the second flight speed according to the current position information, the expected position information, and the topological position information in the formation specifically includes: determining the actual relative position information according to the current position information and the current position information of other UAVs in the formation; determining the expected relative position information according to the expected position information and the expected position information of other UAVs in the formation and the topological position information in the formation; determining the second flight speed based on the consistency protocol according to the actual relative position information and the expected relative position information; Determining the third flight speed according to the current position information and the position relationship with other UAVs in the formation specifically includes: determining the relative distance between two adjacent UAVs according to the current position information, the current position information of other UAVs in the formation and the position relationship with other UAVs in the formation; determining the third flight speed according to the relative distance based on an obstacle function; The calculating of the target flight speed based on the first flight speed, the second flight speed and the third flight speed specifically includes: comparing the second flight speed with a formation control speed threshold to determine the second target flight speed; comparing the third flight speed with an anti-collision control speed threshold to determine the third target flight speed; calculating the target flight speed based on the first flight speed, the second target flight speed and the third target flight speed.

2. The method according to claim 1, characterized in that The receiving the topological position information of the formation and determining the planned path specifically includes: Receive the waypoint location information within the preset flight range, and obtain the virtual center planning path based on the path planning algorithm; Determine, based on the topological position information in the formation, position difference information with respect to the planned path of the virtual center; The planned path is obtained according to the position difference information and based on the path planning algorithm.

3. The method according to claim 1, characterized in that The preset anti-collision threshold includes a danger threshold and a safety threshold, the danger threshold is less than the safety threshold, and the determining the third flight speed according to the relative distance and based on an obstacle function specifically includes: Comparing the relative distance with the danger threshold and the safety threshold to determine an impulse function; The third flight speed is determined according to the impulse function based on an obstacle function.

4. The method according to claim 1, characterized in that: The controlling the formation according to the target flight speed specifically includes: Calculate the unit vector of the target flight speed to obtain the current flight speed; Calculate the flight speed at the last moment based on the current yaw angle information; Calculating the yaw angle at the next moment according to the current flight speed and the flight speed at the previous moment; The formation is controlled according to the target flight speed and the yaw angle at the next moment.

5. A distributed vertical take-off fixed-wing UAV cluster formation control device, characterized in that: Applicable to any UAV in a vertical take-off fixed-wing UAV cluster, including: A planning path determination module is used to receive the topological position information of the formation and determine the planning path; A first flight speed determination module, used to determine a first flight speed according to current position information and expected position information in the planned path; A second flight speed determination module, configured to determine a second flight speed according to the current position information, the expected position information, and the topological position information in the formation; A third flight speed determination module, configured to determine a third flight speed according to the current position information and a position relationship with other UAVs in the formation; a target flight speed determination module, configured to calculate a target flight speed based on the first flight speed, the second flight speed and the third flight speed; A control module, used for controlling the formation according to the target flight speed; The determining of the second flight speed according to the current position information, the expected position information, and the topological position information in the formation specifically includes: determining the actual relative position information according to the current position information and the current position information of other UAVs in the formation; determining the expected relative position information according to the expected position information and the expected position information of other UAVs in the formation and the topological position information in the formation; determining the second flight speed based on the consistency protocol according to the actual relative position information and the expected relative position information; Determining the third flight speed according to the current position information and the position relationship with other UAVs in the formation specifically includes: determining the relative distance between two adjacent UAVs according to the current position information, the current position information of other UAVs in the formation and the position relationship with other UAVs in the formation; determining the third flight speed according to the relative distance based on an obstacle function; The calculating of the target flight speed based on the first flight speed, the second flight speed and the third flight speed specifically includes: comparing the second flight speed with a formation control speed threshold to determine the second target flight speed; comparing the third flight speed with an anti-collision control speed threshold to determine the third target flight speed; calculating the target flight speed based on the first flight speed, the second target flight speed and the third target flight speed.

6. A distributed vertical take-off fixed-wing UAV swarm formation control device, comprising a memory, a processor and a computer program stored in the memory, characterized in that: The processor executes the computer program to implement the steps of the method according to any one of claims 1 to 4.

7. A computer-readable storage medium having a computer program stored thereon, characterized in that: When the computer program is executed by a processor, the steps of the method according to any one of claims 1 to 4 are implemented.

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