A method and system for controlling a UAV cluster based on trajectory parameters

Abstract

The application provides a kind of unmanned aerial vehicle cluster control method and system based on trajectory parameter communication, first, the trajectory is divided by the navigation unmanned aerial vehicle and the current segment trajectory parameter is calculated;Second, the navigation unmanned aerial vehicle encapsulates the current segment trajectory parameter according to the set communication message format, and publishes the trajectory parameter message to the follower unmanned aerial vehicle in its communication range;Then, the follower unmanned aerial vehicle subscribes the trajectory parameter message from the navigation unmanned aerial vehicle, and forwards the trajectory parameter message to the follower unmanned aerial vehicle outside the communication range of the navigation unmanned aerial vehicle;Finally, the follower unmanned aerial vehicle calculates the flight trajectory according to the received trajectory parameter;And travels according to the flight trajectory.The application can not only reduce the data volume of communication, but also reduce the frequency of information exchange by transferring flight path parameters.After the follower unmanned aerial vehicle receives the information of the navigation unmanned aerial vehicle, it only needs to perform simple calculation to complete the path planning within a period of time, and realizes formation control in a distributed manner to maintain the consistency of cluster trajectory.

Description

Technical Field

[0001] This invention relates to the fields of unmanned aerial vehicle (UAV) communication technology and swarm control, and specifically to a UAV swarm control method and system based on trajectory parameter communication. Background Technology

[0002] With the increasing demand for drone applications across various fields, the limited computing power and flight range of a single drone can no longer meet the needs of large-scale missions, leading to the emergence of multi-drone systems. Since the actions of drone swarms are typically mission-driven, swarms usually move in formation to ensure consistency in the trajectories of the drones within the swarm. Based on different communication methods, drone swarm control methods can be categorized into centralized control methods, distributed control methods, and decentralized control methods.

[0003] Among multi-UAV control methods, the centralized "leader-follower" control method is the most common. Its advantage lies in the fact that complex problems involving multiple individuals can be transformed into studies of the movement of a single individual, effectively reducing the number of individual studies. However, this method also has drawbacks: the stability of the entire UAV swarm system is determined by the leader, making it highly dependent. If the leader malfunctions, the entire system will collapse. Furthermore, due to the limited computing and communication resources of UAVs, excessively frequent information or communication exchanges between UAVs can easily lead to network congestion, loss of real-time information, and delayed responses from UAVs to the leader's commands, thus affecting the consistency of the UAV swarm's actions.

[0004] Chinese patent CN110825116B discloses a UAV formation method based on time-varying network topology, belonging to the field of UAV control technology. It includes the following steps: S1, a UAV sends its velocity and position at time t to its neighboring UAVs and receives the position and velocity at time t from its neighboring UAVs; S2, based on the position and velocity of the UAV and all its neighboring UAVs at time t, calculates the output ui(t) of the UAV formation controller; S3, based on the UAV's output ui(t), velocity, and position at time t, calculates the UAV's velocity and position at the next time step and adjusts the UAV accordingly; S4, determines whether the UAV's velocity and position at time t+1 meet the set conditions. If they do, formation is completed; otherwise, t = t+1, and the process returns to step S1. This patent's formation method solves the problem that in poor communication environments where multiple communication links cannot be maintained effectively, UAVs struggle to form a predetermined formation to reach their destination. Summary of the Invention

[0005] This invention takes into account factors such as the limited communication bandwidth, limited computing power, and influence of external communication conditions of UAVs, and proposes a UAV swarm control method and system based on trajectory parameter communication.

[0006] The first aspect of the present invention provides a method for controlling a swarm of unmanned aerial vehicles (UAVs) based on trajectory parameter communication, the method comprising:

[0007] Step 1: The navigator drone divides the trajectory and calculates the parameters of the current segment trajectory, including trajectory type, current position coordinates of the navigator drone, auxiliary parameters, and driving direction.

[0008] Step 2: The lead drone encapsulates the current segment trajectory parameters according to the set communication message format and publishes the trajectory parameter messages to the follower drones within its communication range.

[0009] Step 3: The follower drone subscribes to trajectory parameter messages from the lead drone and forwards the trajectory parameter messages to follower drones outside the lead drone's communication range.

[0010] Step 4: Follow the drone to calculate the flight path of the drone based on the received trajectory parameters; and drive according to the flight path, while preparing to resubscribe to the next segment of trajectory information.

[0011] A second aspect of the present invention provides a drone swarm control system based on trajectory parameter communication, comprising:

[0012] The segmented trajectory parameter calculation module is used to divide the trajectory of the navigation drone and calculate the current segmented trajectory parameters.

[0013] The trajectory parameter message publishing module is used by the lead drone to encapsulate the current segment trajectory parameters according to the set communication message format and publish the trajectory parameter messages to the follow drones within its communication range.

[0014] Trajectory parameter message forwarding module: used to subscribe to trajectory parameter messages from the lead drone and forward trajectory parameter messages to follow drones outside the communication range of the lead drone;

[0015] The local flight trajectory calculation module is used to calculate the local flight trajectory based on the received trajectory parameters of the drone; and to drive according to the flight trajectory, while preparing to resubscribe to the next segment of trajectory information.

[0016] The beneficial effects of this invention are as follows:

[0017] 1) This invention overcomes the problems of excessively high information exchange frequency and excessively high data volume in centralized UAV swarm control systems. Compared with the traditional "leader-follower" topology swarm control method, the proposed solution can optimize the communication bandwidth resources used in formation control, leaving more communication and computing resources for swarm tasks.

[0018] 2) This invention distributes formation control tasks across individual follower drones, reducing the central role of the lead drone and effectively mitigating swarm control failures caused by the failure of the lead drone. By transmitting critical parameters, it reduces the reliance on a single lead drone in traditional tandem flight.

[0019] If a single point of failure occurs during flight, since each drone is guided only by its own calculation results while flying along the current trajectory, and the parameter information is transmitted in the form of broadcast, and each follower drone does not have a fixed lead drone, the failure of any lead drone will not immediately have an adverse effect on the subsequent behavior of the other drones.

[0020] 3) This invention enables swarm control of drones under conditions of limited communication. Since this invention does not require drones to maintain a long-term communication connection, but only transmits a small amount of data at the beginning of each flight segment, it can complete the flight trajectory calculation for each drone. Therefore, this invention demonstrates certain advantages in environments with limited communication or resources. Attached Figure Description

[0021] Figure 1 This is a flowchart of the invention;

[0022] Figure 2 This is a flowchart of the trajectory parameter processing of the navigation drone of the present invention;

[0023] Figure 3 This is a flowchart of the trajectory parameter processing for the drone in this invention. Detailed Implementation

[0024] To make the objectives, technical solutions, and advantages of this invention clearer, the invention will be further described in detail below with reference to the accompanying drawings and embodiments.

[0025] Implementation Column 1:

[0026] Please refer to Figure 1 As shown, Figure 1 This is a flowchart of a UAV swarm control method based on trajectory parameter communication according to the present invention. This embodiment includes the following steps:

[0027] Step 1: Design the communication message format for cluster control under DDS communication mode, including: trajectory type field (uint8 type), navigator current position coordinate field ([double,double], a pair of variables), auxiliary parameter field ([double,double], a pair of variables), and driving direction field (double type).

[0028] Step 2: The lead drone divides the trajectory and calculates the parameters of the current segment trajectory, including trajectory type, current position coordinates of the lead drone, auxiliary parameters (center coordinates of the circle containing the trajectory curve / straight-line travel distance), and travel direction.

[0029] Step 3: The lead drone encapsulates the trajectory parameters according to the DDS custom message format and publishes the trajectory parameter messages to the follower drones within its communication range.

[0030] Step 4: The follower drone subscribes to trajectory parameter messages from the lead drone and forwards the trajectory parameter messages to follower drones outside the lead drone's communication range.

[0031] Step 5: Follow the drone to calculate the flight trajectory of the drone based on the received trajectory parameters.

[0032] Step 6: Follow the drone along the calculated trajectory and prepare to resubscribe to the next segment of trajectory information.

[0033] Implement Column 2:

[0034] Please refer to Figure 2 As shown, Figure 2 This is a flowchart illustrating the trajectory parameter processing of the navigation drone in Embodiment 2 of the present invention. This method is implemented in step 2 of Embodiment 1, and includes the following steps:

[0035] Step 2.1: Determine the trajectory type based on the starting position of the navigation drone, the ending position of the current trajectory segment, and any waypoint. When the starting point, ending point, and waypoint are on the same straight line, the trajectory is a straight line (type code 0); otherwise, it is a curve (type code 1).

[0036] Step 2.2: Determine the content of the auxiliary parameter field based on the trajectory type. If the trajectory type is linear, the auxiliary parameter field is the travel distance; if the trajectory type is curved, based on the mathematical principle that three points not on the same straight line determine a circle, calculate the coordinates of the intersection of the perpendicular bisectors of the three sides of a triangle with the three points as vertices: the starting position of the navigating drone, the ending position of the current trajectory segment, and any path point. That is, calculate the coordinates of the center of the circle containing the curve, and fill this value into the auxiliary parameter field.

[0037] Step 2.3: Determine the driving direction. If the trajectory type is straight, the driving direction is the direction indicated by the magnetic compass; if the trajectory type is curved, the driving direction is calculated using the arc length formula based on the expected trajectory length. If the driving direction is clockwise along the trajectory circle, the driving direction is positive; otherwise, it is negative.

[0038] Implement column 3:

[0039] Please refer to Figure 3 As shown, Figure 3 This is a flowchart of the trajectory parameter processing for following the UAV in Embodiment 3 of the present invention. This method is implemented in step 5 of Embodiment 1, and includes the following steps:

[0040] Step 5.1: Parse the trajectory type. If the type code is 0, it is a straight trajectory; if the type code is 1, it is a curved trajectory.

[0041] Step 5.2: If the trajectory is a straight line, the trajectory of the drone can be determined based on the direction and distance traveled. If the trajectory is a curve, the center coordinates of the trajectory circle of the drone following the drone are determined by the position of the lead drone, the position of the drone itself, and the center position of the circle on which the lead drone is located, according to the parallelogram law. At the same time, if the direction of travel is positive, the drone travels clockwise along the circular trajectory by the corresponding arc; otherwise, it travels counterclockwise along the circular trajectory by the corresponding arc.

[0042] The drone swarm control method provided in this application can be applied to a terminal, a server, or software running on either a terminal or a server. In some embodiments, the terminal can be a smartphone, tablet, laptop, desktop computer, etc.; the server can be configured as an independent physical server, a server cluster or distributed system composed of multiple physical servers, or a cloud server providing basic cloud computing services such as cloud services, cloud databases, cloud computing, cloud functions, cloud storage, network services, cloud communication, middleware services, domain name services, security services, CDN, and big data and artificial intelligence platforms, but is not limited to the above forms.

[0043] In summary, the embodiments of this application, by transmitting flight path parameters in formation control and maintenance, not only reduce the amount of data communicated but also the frequency of information exchange. After receiving information from the lead drone, the following drone only needs simple calculations to complete path planning for a period of time, achieving distributed formation control and maintaining the consistency of the cluster trajectory. Compared with the patents involved in the background art, this application has lower computational complexity, fewer communication frequencies, higher efficiency, and is less affected by the delays of multiple communication sessions, thus achieving better formation maintenance during flight.

[0044] The embodiments described in this application are for the purpose of more clearly illustrating the technical solutions of the embodiments of this application, and do not constitute a limitation on the technical solutions provided by the embodiments of this application. As those skilled in the art will know, with the evolution of technology and the emergence of new application scenarios, the technical solutions provided by the embodiments of this application are also applicable to similar technical problems. It is understood that the technical solutions shown in the figures do not constitute a limitation on the embodiments of this application, and may include more or fewer steps than shown, or combine certain steps, or different steps.

Claims

1. A method for controlling a UAV swarm based on trajectory parameter communication, characterized in that The method includes the following steps: Step 1: The navigator drone divides the trajectory and calculates the parameters of the current segment trajectory, including trajectory type, current position coordinates of the navigator drone, auxiliary parameters, and direction of travel; Step 2: The lead drone encapsulates the current segment trajectory parameters according to the set communication message format and publishes the trajectory parameter messages to the follower drones within its communication range; Step 3: The follower drone subscribes to trajectory parameter messages from the lead drone and forwards the trajectory parameter messages to follower drones outside the lead drone's communication range; Step 4: Follow the drone to calculate the flight path of the drone based on the received trajectory parameters; and drive according to the flight path, while preparing to resubscribe to the next segment of trajectory information.

2. The UAV swarm control method based on trajectory parameter communication according to claim 1, characterized in that, The communication message format includes a trajectory type field, a navigator current position coordinate field, an auxiliary parameter field, and a driving direction field.

3. The UAV swarm control method based on trajectory parameter communication according to claim 2, characterized in that, The communication message format is based on the DDS communication method.

4. The UAV swarm control method based on trajectory parameter communication according to claim 1, characterized in that, Step 1 is as follows: Step 1.1: Determine the trajectory type based on the starting position of the navigation drone, the ending position of the current trajectory segment, and any waypoint; when the starting point, ending point, and waypoint are on the same straight line, the trajectory is a straight line; otherwise, it is a curve. Step 1.2: Determine the contents of the auxiliary parameter field based on the trajectory type; If the trajectory type is linear, then the auxiliary parameter field is the travel distance; If the trajectory type is a curve, calculate the coordinates of the center of the circle containing the curve; Step 1.3: Determine the driving direction; If the trajectory type is straight, then the direction of travel is the direction indicated by the magnetic compass. If the trajectory type is curved, the driving direction is calculated using the arc length formula based on the expected trajectory length.

5. The UAV swarm control method based on trajectory parameter communication according to claim 4, characterized in that, If the vehicle travels clockwise along the trajectory circle, the direction of travel is positive; otherwise, it is negative.

6. The UAV swarm control method based on trajectory parameter communication according to claim 1, characterized in that, Step 4 specifically involves: analyzing the trajectory type. If the trajectory is a straight line, the travel trajectory of the drone can be determined based on the travel direction and travel distance. If the trajectory is a curve, the coordinates of the center of the trajectory circle of the drone following the drone are determined by the position of the lead drone, the position of the drone itself, and the center position of the trajectory circle of the lead drone, according to the parallelogram law.

7. The UAV swarm control method based on trajectory parameter communication according to claim 6, characterized in that, If the driving direction value is positive, then travel clockwise along the circular trajectory by the corresponding arc; otherwise, travel counterclockwise along the circular trajectory by the corresponding arc.

8. A drone swarm control system based on trajectory parameter communication, characterized in that, include: The segmented trajectory parameter calculation module is used to divide the trajectory of the navigation drone and calculate the current segmented trajectory parameters. The trajectory parameter message publishing module is used by the lead drone to encapsulate the current segment trajectory parameters according to the set communication message format and publish the trajectory parameter messages to the follow drones within its communication range. Trajectory parameter message forwarding module: used to subscribe to trajectory parameter messages from the lead drone and forward trajectory parameter messages to follow drones outside the communication range of the lead drone; The local flight trajectory calculation module is used to calculate the local flight trajectory based on the received trajectory parameters of the drone; and to drive according to the flight trajectory, while preparing to resubscribe to the next segment of trajectory information.

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