Unmanned aerial vehicle formation landing control method, device, equipment and storage medium

Abstract

The application discloses a UAV formation landing control method, device, equipment and storage medium, relates to the technical field of UAV control, and the method comprises the following steps: listening to the homeward signal periodically broadcasted by the long machine in the UAV formation; when the homeward signal is received, or the listening time exceeds the preset time threshold and the preset autonomous landing trigger condition is met, a control instruction is generated, the control instruction is used for switching the flight mode of the UAV from the fixed wing mode to the multi-rotor mode and controlling the UAV to move horizontally to the preset landing reference point, when the UAV reaches the preset landing reference point, the timing is started, and the accumulated waiting time is obtained; a target landing order is acquired, and the target waiting time is determined according to the target landing order; when the accumulated waiting time reaches the target waiting time, the UAV is controlled to complete landing. The application can improve the landing success rate of the UAV formation.

Description

Technical Field

[0001] This application relates to the field of unmanned aerial vehicle (UAV) control technology, and in particular to a method, apparatus, device, and storage medium for controlling the landing of UAV formations. Background Technology

[0002] With the development of electric vertical take-off and landing (eVTOL) compound-wing UAV swarm flight technology, multi-aircraft coordinated landing has become a key aspect to be addressed. Currently, ground stations are used to centrally coordinate UAV swarms to complete landings. However, this method is overly reliant on communication links; if ground station communication fails, UAVs cannot land successfully. Therefore, improving the landing success rate of UAV swarms remains a problem to be solved. Summary of the Invention

[0003] The main objective of this application is to provide a landing control method, apparatus, device, and storage medium for unmanned aerial vehicle (UAV) formations, aiming to solve the technical problem of improving the landing success rate of UAV formations.

[0004] To achieve the above objectives, this application proposes a landing control method for unmanned aerial vehicle (UAV) formations, the method comprising: Listen to the return-to-home signal periodically broadcast by the lead drone in the drone formation. The return-to-home signal is periodically broadcast by the lead drone after it detects that its flight mode has changed from fixed-wing mode to multi-rotor mode, until the preset broadcast duration is reached or the lead drone completes landing. When the return signal is received, or when the listening time exceeds a preset time threshold and the preset autonomous landing trigger condition is met, a control command is generated. The control command is used to switch the UAV's flight mode from fixed-wing mode to multi-rotor mode and control the UAV to move horizontally to a preset landing reference point. When the UAV reaches the preset landing reference point, a timer is started to obtain the cumulative waiting time. Obtain the target landing order and determine the target waiting time based on the target landing order; When the cumulative waiting time reaches the target waiting time, the drone is controlled to descend vertically from the landing reference point until landing is completed.

[0005] In one embodiment, the step of determining the target waiting time based on the target landing order includes: Get the preset unit of staggered peak duration; The target waiting time is obtained based on the preset unit staggered peak time and the target landing order.

[0006] In one embodiment, the step of determining the target waiting time based on the target landing order includes: Get the preset unit of staggered peak duration; The initial waiting time is obtained based on the preset unit staggered peak time and the target landing order; Acquire current wind speed data, altitude difference data with adjacent drones, and descent depth data of preceding drones; The initial waiting time is corrected based on the current wind speed data, the height difference data, and the descent depth data to obtain the target waiting time.

[0007] In one embodiment, the step of controlling the UAV to descend vertically from the landing reference point to complete the landing when the accumulated waiting time reaches the target waiting time includes: When the cumulative waiting time reaches the target waiting time, the current altitude of the preceding UAV is obtained; Determine whether the current altitude of the preceding drone is lower than a preset safe altitude threshold; When the current altitude of the preceding UAV is lower than a preset safe altitude threshold, the UAV is controlled to descend vertically from the landing reference point until landing is completed.

[0008] In one embodiment, the step of obtaining the target landing order includes: The leader receives the order correction information sent by the leader aircraft. The order correction information is generated by the leader aircraft after reordering the drone wingmen in the current list of valid members. The list of valid members is maintained and updated by the leader aircraft based on the heartbeat signals of the drone wingmen. The ranking correction information is determined as the target landing ranking.

[0009] In one embodiment, when the monitoring duration exceeds a preset duration threshold and a preset autonomous landing trigger condition is met, the step of generating a control command includes: When the monitoring duration exceeds the preset duration threshold, obtain the current flight status and the duration of flight of the local machine; Determine whether the current flight status is a cruise state and whether the flight duration exceeds the rated mission duration; When the current flight state is cruise state and the flight time exceeds the rated mission time, it is determined that the preset autonomous landing trigger condition is met, and a control command is generated.

[0010] In one embodiment, before the step of monitoring the return-to-home signal periodically broadcast by the lead drone in the drone formation, the method further includes: Receive configuration messages sent by the primary server; In response to the configuration message, a response confirmation message is sent to the primary machine, the response confirmation message indicating that the configuration message has been successfully received.

[0011] Furthermore, to achieve the above objectives, this application also proposes a landing control device for a drone formation, the drone formation landing control device comprising: The monitoring module is used to monitor the return-to-home signal periodically broadcast by the lead aircraft in the UAV formation. The return-to-home signal is periodically broadcast by the lead aircraft after it detects that its flight mode has changed from fixed-wing mode to multi-rotor mode, until the preset broadcast duration is reached or the lead aircraft completes landing. The generation module is used to generate control commands when the return signal is received, or when the listening time exceeds a preset time threshold and the preset autonomous landing trigger conditions are met. The control commands are used to switch the UAV's flight mode from fixed-wing mode to multi-rotor mode and control the UAV to move horizontally to a preset landing reference point. When the UAV reaches the preset landing reference point, the timing is started to obtain the cumulative waiting time. The determination module is used to obtain the target landing order and determine the target waiting time based on the target landing order; The control module is used to control the UAV to descend vertically from the landing reference point until it completes landing when the cumulative waiting time reaches the target waiting time.

[0012] In addition, to achieve the above objectives, this application also proposes a landing control device for unmanned aerial vehicle (UAV) formations, 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 UAV formation landing control method described above.

[0013] 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 unmanned aerial vehicle formation landing control method described above.

[0014] In addition, to achieve the above objectives, this application also provides a computer program product, which includes a computer program that, when executed by a processor, implements the steps of the unmanned aerial vehicle (UAV) formation landing control method described above.

[0015] This application provides a landing control method for a drone formation. The method involves monitoring a return-to-home (ROW) signal periodically broadcast by the lead drone in the formation. This ROW signal is periodically broadcast by the lead drone after it detects a change in its flight mode from fixed-wing to multi-rotor mode, continuing until a preset broadcast duration is reached or the lead drone completes its landing. Upon receiving the ROW signal, or when the monitoring duration exceeds a preset threshold and a preset autonomous landing trigger condition is met, a control command is generated. This command switches the drone's flight mode from fixed-wing to multi-rotor mode and controls the drone to move horizontally to a preset landing reference point. Once the drone reaches the preset landing reference point, a timer is started to accumulate the waiting time. The target landing priority is obtained, and a target waiting time is determined based on this priority. When the accumulated waiting time reaches the target waiting time, the drone is controlled to descend vertically from the landing reference point until landing is complete. In this application, the ROW signal is sent by the lead drone in the formation, allowing wingmen to initiate the landing process without relying on ground station commands, thus avoiding the problem of the entire formation losing command when the communication link is unstable. Furthermore, when the wingman does not receive a return-to-home signal, it can autonomously trigger the landing process by monitoring for a timeout, without having to wait passively, further reducing its dependence on the communication link. This improves the landing success rate of the drone formation. 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 A flowchart illustrating an embodiment of the unmanned aerial vehicle (UAV) formation landing control method of this application; Figure 2 A schematic diagram of staggered descent of a drone formation provided for Embodiment 1 of the drone formation landing control method of this application; Figure 3 A flowchart illustrating Embodiment 2 of the unmanned aerial vehicle (UAV) formation landing control method of this application; Figure 4 A simplified flowchart illustrating the landing control method for unmanned aerial vehicle (UAV) formations provided in Embodiment 1 of this application; Figure 5 This is a schematic diagram of the module structure of the landing control device for unmanned aerial vehicle formations according to an embodiment of this application; Figure 6 This is a schematic diagram of the equipment structure of the hardware operating environment involved in the unmanned aerial vehicle formation landing 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] This application monitors the return-to-home (ROW) signals periodically broadcast by the lead drone in a swarm. These signals are broadcast periodically by the lead drone after it detects a change in its flight mode from fixed-wing to multi-rotor mode, continuing until a preset broadcast duration is reached or the lead drone completes a landing. Upon receiving the ROW signal, or when the monitoring duration exceeds a preset threshold and a preset autonomous landing trigger condition is met, a control command is generated. This command switches the drone's flight mode from fixed-wing to multi-rotor mode and controls the drone to move horizontally to a preset landing reference point. Once the drone reaches the preset landing reference point, a timer is started to accumulate the waiting time. The target landing priority is obtained, and a target waiting time is determined based on this priority. When the accumulated waiting time reaches the target waiting time, the drone is controlled to descend vertically from the landing reference point until a landing is completed.

[0023] With the development of eVTOL (eVTOL) composite-wing UAV swarm flight technology, multi-aircraft coordinated landing has become a key challenge. Currently, ground stations are used to centrally coordinate UAV swarms and complete landings. However, this method is overly reliant on communication links; if ground station communication fails, UAVs cannot land successfully. Therefore, improving the landing success rate of UAV swarms remains a problem to be solved.

[0024] In this application, the return-to-home signal is sent by the lead drone in the formation, allowing wingmen to initiate the landing process without relying on ground station commands, thus avoiding the problem of the entire formation losing command when the communication link becomes unstable. Furthermore, if a wingman does not receive the return-to-home signal, it can autonomously trigger the landing process by listening for a timeout, without passively waiting, further reducing dependence on the communication link. Therefore, this improves the landing success rate of the drone formation.

[0025] If this application involves user-related data, it was obtained with the user's permission or consent; that is, when this application is used in a specific product or technology, user permission is required to obtain and process the relevant data, and the processing of the relevant data must comply with the relevant laws, regulations and regulatory standards of the relevant countries and regions.

[0026] Based on this, embodiments of this application provide a landing control method for unmanned aerial vehicle (UAV) formations, referring to... Figure 1 , Figure 1 This is a flowchart illustrating the first embodiment of the unmanned aerial vehicle (UAV) formation landing control method of this application.

[0027] In this embodiment, the landing control method for the UAV formation includes steps S10 to S40: Step S10: Listen to the return-to-home signal periodically broadcast by the lead drone in the drone formation. The return-to-home signal is periodically broadcast by the lead drone after it detects that its flight mode has changed from fixed-wing mode to multi-rotor mode, until the preset broadcast duration is reached or the lead drone completes landing. It should be noted that the executing entity in this embodiment can be a computing service device with data processing, network communication, and program execution functions, such as a tablet computer, personal computer, or mobile phone, or an electronic device capable of performing the above functions, such as a chip for a wingman in a drone formation. The following description uses a chip for a wingman in a drone formation as an example to illustrate this embodiment and the subsequent embodiments.

[0028] It should be noted that this application pertains to eVTOL hybrid-wing UAV formations. The formation consists of a lead UAV (ID=1) and at least one wingman (ID increments from 2), which can exchange formation coordination messages via a wireless data link. The UAV formation geometry (line, wedge, lead-centered, etc.) is a parameter configuration, and this solution does not impose restrictions on it. The endpoint of the formation mission is when all UAVs uniformly switch from fixed-wing mode back to multi-rotor mode, at which point the UAVs can begin landing. The return-to-home signal is sent from the lead UAV to the wingman. During flight, the lead UAV continuously monitors its own flight mode status. When a boundary event occurs indicating a transition from fixed-wing to multi-rotor mode, it is recognized as the mission endpoint being reached. Since the lead UAV uses its own physical state change as the trigger condition, it does not need to listen for specific commands; whether the lead UAV reaches the automatic landing waypoint, triggers automatic return-to-home, or manually switches, it does not affect the lead UAV sending the return-to-home signal. To ensure that the wingman receives the return-to-home signal, the lead aircraft can continuously broadcast the signal at a fixed interval of T_period until it confirms that it has completed landing or reaches the maximum broadcast duration limit (which can be preset manually). T_period can be set to 1 to 3 seconds.

[0029] It should be noted that messages within the formation can be handled in three levels according to their importance. Configuration messages (such as landing control parameters) can use acknowledgment and timeout retransmission methods. For example, a 2-second timeout allows for 3 retransmissions; if all 3 retransmissions fail, the mission enters the return-to-base phase and is aborted. Control messages (such as return-to-base broadcasts) use redundant broadcasting and do not require acknowledgment. Status messages (crew heartbeats) are broadcast every 0.2 seconds to determine whether each aircraft is online.

[0030] In one feasible approach, prior to the step of monitoring the return-to-home signal periodically broadcast by the lead drone in the drone formation, the method further includes: receiving a configuration message sent by the lead drone; and in response to the configuration message, sending a response confirmation message to the lead drone, the response confirmation message indicating that the configuration message has been successfully received.

[0031] It should be noted that before the formation flight mission begins, the lead aircraft needs to send configuration messages to each wingman. Configuration messages are the type of message used to transmit mission parameters in a formation mission; the landing control configuration messages involved in this application may include at least one of a preset unit staggered peak duration, a preset duration threshold, and a preset safe altitude threshold. A formula for calculating the initial waiting time is provided. After receiving the configuration message from the lead aircraft, the wingman needs to send a response confirmation message to the lead aircraft. The response confirmation message is used to indicate to the lead aircraft that the wingman has successfully received the configuration message and can continue to execute subsequent tasks. Through the response confirmation mechanism of configuration messages, the formation can confirm that all members have correctly received the mission parameters before the mission begins, avoiding formation coordination failure due to missing configuration information.

[0032] Step S20: When the return signal is received, or the listening time exceeds the preset time threshold and the preset autonomous landing trigger condition is met, a control command is generated. The control command is used to switch the UAV's flight mode from fixed-wing mode to multi-rotor mode and control the UAV to move horizontally to the preset landing reference point. When the UAV reaches the preset landing reference point, the timer is started to obtain the cumulative waiting time. It should be noted that during the formation cruise phase, all aircraft are in fixed-wing mode. As the formation approaches the mission endpoint, the lead aircraft needs to switch from fixed-wing mode back to multi-rotor mode to complete the final landing. The preset landing reference point refers to the point directly above the pre-stored Home point coordinates, at the same altitude as the drone's current altitude.

[0033] It should be noted that upon receiving the return-to-home signal, the landing procedure can naturally be initiated, generating control commands to guide the drone's descent. However, there is a possibility of the lead aircraft and wingman losing contact. Therefore, the wingman can maintain a local timer. If no return-to-home signal from the lead aircraft is received within a preset timeout period T_timeout, it will no longer passively wait but will directly trigger the landing procedure.

[0034] In one feasible approach, the step of generating a control command when the return-to-home signal is received or the monitoring duration exceeds a preset duration threshold includes: when the monitoring duration exceeds the preset duration threshold, obtaining the current flight status and the flight duration of the aircraft; determining whether the current flight status is a cruise state and whether the flight duration exceeds the rated mission duration; when the current flight status is a cruise state and the flight duration exceeds the rated mission duration, determining that a preset autonomous landing trigger condition is met, and generating a control command.

[0035] It should be noted that in the case of a listening timeout, that is, when the listening duration exceeds the preset threshold, it is also necessary to determine whether the preset autonomous landing trigger conditions are met. Specifically, the wingman generates a control command only when it detects that it is still in cruise mode and the cruise duration exceeds the rated mission duration limit. In this case, T_timeout can be set to twice the longest broadcast window of the lead aircraft.

[0036] Step S30: Obtain the target landing order and determine the target waiting time based on the target landing order; It's important to note that, on a physics level, when a multi-rotor eVTOL descends near the ground, the downwash airflow directly beneath the fuselage transforms into a horizontal outwash due to ground effect. Furthermore, the downwash and outwash intensity of a typical eVTOL prototype can reach hurricane-level wind speeds. Mechanistically, the distributed configuration of a multi-rotor also creates directional high-speed airflow between adjacent rotors; this is an inherent characteristic of multi-rotor configurations and is not significant in a helicopter's single large rotor. When multiple aircraft descend simultaneously, the downwash and outwash airfields of adjacent aircraft push against each other horizontally, generating nonlinear disturbances. The lateral radius of this airflow interaction is much larger than the aircraft's scale and is amplified by ground effect with decreasing altitude. Even with a large horizontal distance between aircraft on the ground, the airflows will still collide if they descend simultaneously at low altitude. Therefore, staggered landing times are necessary to separate the downwash airfields of adjacent aircraft over time. Thus, even with a flat landing site and sufficient initial horizontal spacing between aircraft, simultaneous multi-aircraft descent is not suitable. Therefore, staggered landing times are recommended for drones.

[0037] It should be noted that the target landing order can be determined based on the ID number of each wingman. The ID number is initially assigned, with the lead aircraft's ID number being 1, and the wingmen's ID numbers starting from 2 and sequentially increasing. The target waiting time refers to how long the wingman needs to wait before it can begin its descent. To ensure staggered drone landings, the target waiting time for each wingman can be calculated based on its target landing order.

[0038] In one feasible approach, the step of obtaining the target landing order includes: receiving order correction information issued by the lead aircraft, wherein the order correction information is generated by the lead aircraft after reordering the drone wingmen in the current effective member list, and the effective member list is maintained and updated by the lead aircraft based on the heartbeat signals of the drone wingmen; and determining the order correction information as the target landing order.

[0039] It should be noted that when all members of the drone formation are functioning normally, using the ID number as the target landing order is fine. However, if a wingman loses contact, for example, if drone number 3 in the formation loses contact midway, drone number 4 will still take a considerable amount of time to begin its descent, and drone number 3 will essentially no longer be able to reappear, meaning drone number 4 has essentially wasted some time.

[0040] Therefore, in this embodiment, the lead aircraft can maintain a "list of valid members," which can be updated in real time based on member heartbeats. Members that fail to respond for several consecutive cycles can be marked as out of contact and removed from the list. After removal, the descent order of the remaining aircraft in the list can be recounted to ensure continuity and eliminate gaps. For example, in a 5-aircraft formation with original IDs 1 to 5, if aircraft number 3 loses contact midway, the system can remove it from the list, and the remaining aircraft (1, 2, 4, and 5) can be recounted. Aircraft number 1 remains in the first position, aircraft number 2 in the second, aircraft number 4 moves to the third, and aircraft number 5 moves to the fourth. At this time, the wingman's ID number is not modified; instead, a new wingman's descent order number is assigned as the target landing order. This way, the descent window originally occupied by aircraft number 3 is filled sequentially by the following aircraft, preventing invalid waiting and ensuring the total formation landing time is not unnecessarily extended.

[0041] In one feasible approach, the step of determining the target waiting time based on the target landing order includes: obtaining a preset unit staggered peak time; and obtaining the target waiting time based on the preset unit staggered peak time and the target landing order.

[0042] It should be noted that the target landing order can be multiplied by the preset unit staggered peak time to obtain the target waiting time for each wingman. The formula is: T_wait(i) = T_unit × (i 1) Where T_wait(i) is the waiting time (in seconds) for the i-th aircraft from completing its homing to initiating its vertical descent, i is the target landing priority used for peak-shifting waiting calculations, and T_unit is the preset unit peak-shifting time, which can be 3 seconds. (See reference...) Figure 2 , Figure 2 This is a diagram illustrating staggered descents of drone formations. Figure 2 In the diagram, 1, 2, 3, and 4 represent the target landing order of the drone. This means the target waiting time for the drone is 0, 3, 6, and 9 seconds respectively.

[0043] Step S40: When the accumulated waiting time reaches the target waiting time, control the UAV to descend vertically from the landing reference point until landing is completed.

[0044] It should be noted that when the cumulative waiting time reaches the target waiting time, the previous drone has already landed for a considerable period of time, and the drone can be controlled to descend vertically from the landing reference point until it completes the landing.

[0045] In one feasible approach, the step of controlling the UAV to descend vertically from the landing reference point to complete the landing when the accumulated waiting time reaches the target waiting time includes: obtaining the current altitude of the preceding UAV when the accumulated waiting time reaches the target waiting time; determining whether the current altitude of the preceding UAV is lower than a preset safe altitude threshold; and controlling the UAV to descend vertically from the landing reference point to complete the landing when the current altitude of the preceding UAV is lower than the preset safe altitude threshold.

[0046] It should be noted that, in addition to the cumulative waiting time reaching the target waiting time, an additional restriction can be added: determining the current altitude of the preceding drone. If the current altitude of the preceding drone is lower than a preset safe altitude threshold, the drone is controlled to descend vertically from the landing reference point until landing is completed. This completely separates the time interval between drone landings. The preceding drone refers to the drone that lands before the target drone in the landing sequence, i.e., the drone that lands before this drone.

[0047] This embodiment monitors the return-to-home (ROW) signals periodically broadcast by the lead drone in a formation. These signals are periodically broadcast by the lead drone after it detects a change in its flight mode from fixed-wing to multi-rotor mode, continuing until a preset broadcast duration is reached or the lead drone completes its landing. Upon receiving the ROW signal, or when the monitoring duration exceeds a preset threshold and a preset autonomous landing trigger condition is met, a control command is generated. This command switches the drone's flight mode from fixed-wing to multi-rotor mode and controls the drone to move horizontally to a preset landing reference point. Once the drone reaches the reference point, a timer is started to accumulate the waiting time. The target landing priority is obtained, and the target waiting time is determined based on this priority. When the accumulated waiting time reaches the target waiting time, the drone is controlled to descend vertically from the landing reference point until landing is complete. In this embodiment, the ROW signal is sent by the lead drone in the formation, allowing wingmen to initiate the landing process without relying on ground station commands, thus avoiding the problem of the entire formation losing command when the communication link is unstable. Furthermore, when the wingman does not receive a return-to-home signal, it can autonomously trigger the landing process by monitoring for a timeout, without having to wait passively, further reducing its dependence on the communication link. This improves the landing success rate of the drone formation.

[0048] Based on the first embodiment of this application, in the second embodiment of this application, the content that is the same as or similar to that in the first embodiment described above can be referred to the above description, and will not be repeated hereafter. Based on this, please refer to... Figure 3 Step S30 also includes steps S301 to S303: Step S301: Obtain the preset unit staggered peak duration; It should be noted that the preset unit staggered time is a basic fixed time. Each drone can obtain a waiting time based on the target landing order and the preset unit staggered time.

[0049] Step S302: Obtain the initial waiting time based on the preset unit staggered peak time and the target landing order; It should be noted that the formula for calculating the initial waiting time is: T_wait(i) = T_unit × (i 1) Where T_wait(i) is the waiting time from the completion of the homing of the i-th aircraft to the initiation of vertical descent, i is the target landing order used for peak waiting calculation, and T_unit is the preset unit peak waiting time, which can be 3 seconds.

[0050] Step S303: Obtain current wind speed data, altitude difference data with adjacent drones, and descent depth data of preceding drones; It should be noted that using a fixed delay of only one unit of staggered waiting time (e.g., 3 seconds) may not be suitable for environmental influences. For example, in windy conditions, the downwash airflow is dispersed quickly, making 3 seconds too conservative, while in calm conditions, 3 seconds may not be sufficient. Therefore, current wind speed data can be used to adjust the initial waiting time. Additionally, the altitude difference data with adjacent drones and the descent depth data of preceding drones can be used as correction factors to obtain a more reasonable waiting time.

[0051] Step S304: Correct the initial waiting time based on the current wind speed data, the height difference data, and the descent depth data to obtain the target waiting time.

[0052] It should be noted that the formula for calculating the target waiting time is: T_wait(i)=α(i 1)+β·f_wind+γ·f_alt+δ·f_lead f_wind= k1·v_wind f_alt= k2·Δh f_lead= k3·(h_init h_lead) Where T_wait(i) is the waiting time for the i-th drone from completing its homing to initiating its vertical descent, i is the target landing order used for peak-shifting waiting calculation, α is the basic peak-shifting coefficient, typically ranging from 2 to 5 seconds. β, γ, and δ are dimensionless weighting coefficients. f_wind is the wind speed correction term, f_alt is the altitude difference correction term with adjacent drones, and f_lead is the descent depth correction term for the preceding drone. v_wind represents the wind speed value; the larger v_wind is, the faster the downwash airflow is dispersed, allowing for an earlier descent; Δh is the altitude difference between the drone and adjacent drones; the larger the altitude difference, the greater the natural staggered time, and the less additional peak-shifting time is required; (h_init h_lead is the initial altitude of the preceding drone minus the current altitude, which is the altitude already descended. The deeper the preceding drone descends, the safer the current drone is, and the earlier it can descend. α, β, γ, δ and k1, k2, k3 are all empirical coefficients that can be determined based on the specific drone model, safety interval requirements, and preset safety margins, and can be calibrated through simulation or experimentation.

[0053] This embodiment obtains a preset unit staggered peak time; it then calculates an initial waiting time based on the preset unit staggered peak time and the target landing order; it acquires current wind speed data, altitude difference data with adjacent drones, and descent depth data of the preceding drone; and it corrects the initial waiting time based on the current wind speed data, the altitude difference data, and the descent depth data to obtain the target waiting time. This embodiment adaptively adjusts the fixed staggered peak time by introducing three environmental correction terms: current wind speed, adjacent altitude difference, and preceding drone descent depth. This allows the target waiting time to dynamically change according to the real-time environment, avoiding efficiency losses caused by excessively long fixed waiting times while ensuring safety.

[0054] For example, to help understand the implementation flow of the UAV formation landing control method obtained by combining this embodiment with the above embodiment one, please refer to... Figure 4 , Figure 4A simplified flowchart of a landing control method for a UAV formation is provided. Specifically: During formation flight, the lead UAV (ID=1) periodically broadcasts a return-to-home signal when its flight mode changes from fixed-wing to multi-rotor. The lead UAV, as the first-order UAV, participates in a unified staggered landing sequence and executes landing according to the landing control strategy corresponding to its first order. In this implementation where the lead UAV participates in the unified staggered landing sequence, the target waiting time for the lead UAV is the waiting time corresponding to its first order. Meanwhile, the wingman UAV (ID=i, i is greater than or equal to 2), upon receiving the lead UAV's return-to-home signal, changes its flight mode from fixed-wing to multi-rotor, returns to its horizontal position at the landing reference point, and starts timing. It calculates the target waiting time based on its target landing order, and when the actual waiting time reaches the target waiting time, it initiates a vertical descent control command and begins vertical descent.

[0055] It should be noted that the above examples are only for understanding this application and do not constitute a limitation on the landing control method of the UAV formation in this application. Any simple modifications based on this technical concept are within the protection scope of this application.

[0056] This application also provides a landing control device for drone formations; please refer to... Figure 5 The landing control device for the drone formation includes: The monitoring module 10 is used to monitor the return-to-home signal periodically broadcast by the lead aircraft in the UAV formation. The return-to-home signal is periodically broadcast by the lead aircraft after it detects that its flight mode has changed from fixed-wing mode to multi-rotor mode, until the preset broadcast duration is reached or the lead aircraft completes landing. The generation module 20 is used to generate a control command when the return signal is received, or when the listening time exceeds a preset time threshold and the preset autonomous landing trigger condition is met. The control command is used to switch the UAV's flight mode from fixed-wing mode to multi-rotor mode and control the UAV to move horizontally to a preset landing reference point. When the UAV reaches the preset landing reference point, the timer is started to obtain the cumulative waiting time. The determination module 30 is used to obtain the target landing order and determine the target waiting time based on the target landing order; The control module 40 is used to control the UAV to descend vertically from the landing reference point until it completes landing when the cumulative waiting time reaches the target waiting time.

[0057] This application monitors the periodic broadcast return-to-home (RTW) signals from the lead drone in a formation. The RWT signals are periodically broadcast by the lead drone after it detects a change in its flight mode from fixed-wing to multi-rotor mode, continuing until a preset broadcast duration is reached or the lead drone completes its landing. Upon receiving the RWT signal, or when the monitoring duration exceeds a preset threshold and a preset autonomous landing trigger condition is met, a control command is generated. This control command switches the drone's flight mode from fixed-wing to multi-rotor mode and controls the drone to move horizontally to a preset landing reference point. Once the drone reaches the preset landing reference point, a timer is started to accumulate the waiting time. The target landing priority is obtained, and the target waiting time is determined based on this priority. When the accumulated waiting time reaches the target waiting time, the drone is controlled to descend vertically from the landing reference point until landing is complete. In this application, the RWT signal is sent by the lead drone in the formation, allowing wingmen to initiate the landing process without relying on ground station commands, thus avoiding the problem of the entire formation losing command when the communication link is unstable. Furthermore, when the wingman does not receive a return-to-home signal, it can autonomously trigger the landing process by monitoring for a timeout, without having to wait passively, further reducing its dependence on the communication link. This improves the landing success rate of the drone formation.

[0058] In one embodiment, the determining module 30 is further configured to obtain a preset unit staggered peak duration; and to obtain the target waiting time based on the preset unit staggered peak duration and the target landing order.

[0059] In one embodiment, the determining module 30 is further configured to obtain a preset unit staggered peak time; obtain an initial waiting time based on the preset unit staggered peak time and the target landing order; obtain current wind speed data, altitude difference data with adjacent UAVs, and descent depth data of preceding UAVs; and correct the initial waiting time based on the current wind speed data, the altitude difference data, and the descent depth data to obtain the target waiting time.

[0060] In one embodiment, the control module 40 is further configured to: obtain the current altitude of the preceding UAV when the accumulated waiting time reaches the target waiting time; determine whether the current altitude of the preceding UAV is lower than a preset safe altitude threshold; and control the UAV to descend vertically from the landing reference point to complete the landing when the current altitude of the preceding UAV is lower than the preset safe altitude threshold.

[0061] In one embodiment, the determining module 30 is further configured to receive priority correction information issued by the lead aircraft, the priority correction information being generated by the lead aircraft after reordering the drone wingmen in the current effective member list, the effective member list being maintained and updated by the lead aircraft based on the heartbeat signals of the drone wingmen; and to determine the priority correction information as the target landing priority.

[0062] In one embodiment, the generation module 20 is further configured to, when the monitoring duration exceeds a preset duration threshold, obtain the current flight status and the flight duration of the local machine; determine whether the current flight status is a cruise state and whether the flight duration exceeds the rated mission duration; when the current flight status is a cruise state and the flight duration exceeds the rated mission duration, determine that the preset autonomous landing trigger condition is met, and generate control commands.

[0063] In one embodiment, the monitoring module 10 is further configured to receive a configuration message sent by the primary machine; and in response to the configuration message, send an acknowledgment message to the primary machine, the acknowledgment message indicating that the configuration message has been successfully received.

[0064] The drone formation landing control device provided in this application, employing the drone formation landing control method in the above embodiments, can solve the technical problem of improving the landing success rate of drone formations. Compared with the prior art, the beneficial effects of the drone formation landing control device provided in this application are the same as those of the drone formation landing control method provided in the above embodiments, and other technical features in the drone formation landing control device are the same as those disclosed in the methods of the above embodiments, and will not be repeated here.

[0065] This application provides a landing control device for a drone formation, comprising: 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, the instructions being executed by the at least one processor to enable the at least one processor to perform the drone formation landing control method of the above embodiment 1.

[0066] The following is for reference. Figure 6 The diagram illustrates a structural schematic of a landing control device suitable for implementing the drone formations in the embodiments of this application. The landing control device for drone formations 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), PADs (Portable Application Description), PMPs (Portable Media Players), in-vehicle terminals (e.g., in-vehicle navigation terminals), and fixed terminals such as digital TVs and desktop computers. Figure 6 The landing control device for the drone formation shown is merely an example and should not impose any limitations on the functionality and scope of use of the embodiments of this application.

[0067] like Figure 6 As shown, the landing control equipment for a drone formation 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 a program stored in ROM (Read Only Memory) 1002 or a program 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 drone formation landing control equipment. 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 landing control equipment of the drone formation to communicate wirelessly or wiredly with other equipment to exchange data. While the figure shows a landing control equipment for a drone formation with various systems, it should be understood that implementation or possession of all the systems shown is not required. More or fewer systems may be implemented alternatively.

[0068] 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.

[0069] The drone formation landing control device provided in this application, employing the drone formation landing control method in the above embodiments, can solve the technical problem of improving the landing success rate of drone formations. Compared with the prior art, the beneficial effects of the drone formation landing control device provided in this application are the same as those of the drone formation landing control method provided in the above embodiments, and other technical features in the drone formation landing control device are the same as those disclosed in the previous embodiment method, and will not be repeated here.

[0070] 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.

[0071] 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.

[0072] 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 unmanned aerial vehicle formation landing control method in the above embodiments.

[0073] 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.

[0074] The aforementioned computer-readable storage medium may be included in the landing control equipment of the UAV formation; or it may exist independently and not be assembled into the landing control equipment of the UAV formation.

[0075] The aforementioned computer-readable storage medium carries one or more programs. When these programs are executed by the landing control equipment of the UAV formation, the landing control equipment of the UAV formation performs the following actions: It listens to the return-to-home signal periodically broadcast by the lead UAV in the formation. This return-to-home signal is periodically broadcast by the lead UAV after it detects that its flight mode has changed from fixed-wing mode to multi-rotor mode, until a preset broadcast duration is reached or the lead UAV completes landing. When the return-to-home signal is received, or when the listening duration exceeds a preset duration threshold and a preset autonomous landing trigger condition is met, the equipment generates a control command. This control command switches the UAV's flight mode from fixed-wing mode to multi-rotor mode and controls the UAV to move horizontally to a preset landing reference point. After the UAV reaches the preset landing reference point, it starts a timer to obtain the cumulative waiting time. It obtains the target landing priority and determines the target waiting time based on the target landing priority. When the cumulative waiting time reaches the target waiting time, it controls the UAV to descend vertically from the landing reference point until landing is completed.

[0076] 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).

[0077] 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.

[0078] 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.

[0079] The readable storage medium provided in this application is a computer-readable storage medium that stores computer-readable program instructions (i.e., computer programs) for executing the above-described unmanned aerial vehicle (UAV) formation landing control method, which can solve the technical problem of improving the landing success rate of UAV formations. Compared with the prior art, the beneficial effects of the computer-readable storage medium provided in this application are the same as the beneficial effects of the UAV formation landing control method provided in the above embodiments, and will not be repeated here.

[0080] This application also provides a computer program product, including a computer program that, when executed by a processor, implements the steps of the above-described unmanned aerial vehicle (UAV) formation landing control method.

[0081] The computer program product provided in this application can solve the technical problem of improving the landing success rate of drone formations. Compared with the prior art, the beneficial effects of the computer program product provided in this application are the same as those of the drone formation landing control method provided in the above embodiments, and will not be repeated here.

[0082] 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 landing control method for unmanned aerial vehicle (UAV) formations, characterized in that, The method includes: Listen to the return-to-home signal periodically broadcast by the lead drone in the drone formation. The return-to-home signal is periodically broadcast by the lead drone after it detects that its flight mode has changed from fixed-wing mode to multi-rotor mode, until the preset broadcast duration is reached or the lead drone completes landing. When the return signal is received, or when the listening time exceeds a preset time threshold and the preset autonomous landing trigger condition is met, a control command is generated. The control command is used to switch the UAV's flight mode from fixed-wing mode to multi-rotor mode and control the UAV to move horizontally to a preset landing reference point. When the UAV reaches the preset landing reference point, a timer is started to obtain the cumulative waiting time. Obtain the target landing order and determine the target waiting time based on the target landing order; When the cumulative waiting time reaches the target waiting time, the UAV is controlled to descend vertically from the landing reference point until landing is completed.

2. The method as described in claim 1, characterized in that, The step of determining the target waiting time based on the target landing order includes: Get the preset unit of staggered peak duration; The target waiting time is obtained based on the preset unit staggered peak time and the target landing order.

3. The method as described in claim 1, characterized in that, The step of determining the target waiting time based on the target landing order includes: Get the preset unit of staggered peak duration; The initial waiting time is obtained based on the preset unit staggered peak time and the target landing order; Acquire current wind speed data, altitude difference data with adjacent drones, and descent depth data of preceding drones; The initial waiting time is corrected based on the current wind speed data, the height difference data, and the descent depth data to obtain the target waiting time.

4. The method as described in claim 1, characterized in that, The step of controlling the UAV to descend vertically from the landing reference point to complete the landing when the accumulated waiting time reaches the target waiting time includes: When the cumulative waiting time reaches the target waiting time, obtain the current altitude of the preceding UAV; Determine whether the current altitude of the preceding drone is lower than a preset safe altitude threshold; When the current altitude of the preceding UAV is lower than a preset safe altitude threshold, the UAV is controlled to descend vertically from the landing reference point until landing is completed.

5. The method as described in claim 1, characterized in that, The step of obtaining the target landing order includes: The leader receives the order correction information sent by the leader aircraft. The order correction information is generated by the leader aircraft after reordering the drone wingmen in the current list of valid members. The list of valid members is maintained and updated by the leader aircraft based on the heartbeat signals of the drone wingmen. The target landing order is determined based on the aforementioned order correction information.

6. The method as described in claim 1, characterized in that, When the monitoring duration exceeds a preset duration threshold and the preset autonomous landing trigger condition is met, the step of generating a control command includes: When the monitoring duration exceeds the preset duration threshold, obtain the current flight status and the duration of flight of the local machine; Determine whether the current flight status is a cruise state and whether the flight duration exceeds the rated mission duration; When the current flight state is cruise state and the flight time exceeds the rated mission time, it is determined that the preset autonomous landing trigger condition is met, and a control command is generated.

7. The method as described in claim 1, characterized in that, Before the step of monitoring the return-to-home signal periodically broadcast by the lead drone in the drone formation, the method further includes: Receive configuration messages sent by the primary server; In response to the configuration message, a response confirmation message is sent to the primary machine, the response confirmation message indicating that the configuration message has been successfully received.

8. A landing control device for unmanned aerial vehicle (UAV) formations, characterized in that, The device includes: The monitoring module is used to monitor the return-to-home signal periodically broadcast by the lead aircraft in the UAV formation. The return-to-home signal is periodically broadcast by the lead aircraft after it detects that its flight mode has changed from fixed-wing mode to multi-rotor mode, until the preset broadcast duration is reached or the lead aircraft completes landing. The generation module is used to generate control commands when the return signal is received, or when the listening time exceeds a preset time threshold and the preset autonomous landing trigger conditions are met. The control commands are used to switch the UAV's flight mode from fixed-wing mode to multi-rotor mode and control the UAV to move horizontally to a preset landing reference point. When the UAV reaches the preset landing reference point, the timing is started to obtain the cumulative waiting time. The determination module is used to obtain the target landing order and determine the target waiting time based on the target landing order; The control module is used to control the UAV to descend vertically from the landing reference point until it completes landing when the cumulative waiting time reaches the target waiting time.

9. A landing control device for unmanned aerial vehicle (UAV) formations, 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 unmanned aerial vehicle formation landing 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 unmanned aerial vehicle formation landing control method as described in any one of claims 1 to 7.

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