Self-assembled unit and combined unmanned aerial vehicle system and scheduling method

Abstract

The invention belongs to the technical field of unmanned aerial vehicles, and discloses a self-assembled unit and combined unmanned aerial vehicle system and a scheduling method, and the method comprises the steps: S1, building a mechanical structure of an unmanned aerial vehicle suitable for the connection of two or more unit unmanned aerial vehicles; s2, a variable unmanned aerial vehicle circuit system is built, and independent operation of a single-machine circuit system and combined operation of two or more unmanned aerial vehicle circuit systems are achieved; s3, establishing a communication routing system between unit unmanned aerial vehicles to realize real-time data communication between the unmanned aerial vehicles; s4, an unmanned aerial vehicle flight control system is built, and single-machine flight control and a flight control task after two or more unmanned aerial vehicles are combined are achieved; s5, establishing a unit and combination unmanned aerial vehicle scheduling system based on task allocation, and sending an instruction to the system through a built-in ground station for remote scheduling; the system solves the problems of fixed load and cruising ability and poor universality of various single unmanned aerial vehicles, and realizes self-assembly and dissociation of multiple single unmanned aerial vehicles and flight control and intelligent scheduling of single and combined unmanned aerial vehicles.

Description

Technical Field

[0001] This invention relates to the field of unmanned aerial vehicle (UAV) technology, and more specifically to a self-assembling unit and combination UAV system and a scheduling method. Background Technology

[0002] In recent years, with increasing societal emphasis on the low-altitude economy, drone technology has developed rapidly. Drones have wide applications in various fields such as aerial photography, logistics, food delivery, agricultural spraying, environmental monitoring, and emergency rescue. However, the payload and endurance of a single drone are relatively fixed, limiting its ability to perform only specific tasks and lacking flexibility and scalability. Consequently, numerous drones designed to meet diverse task requirements have been invented, but while addressing various needs, this has resulted in wasted resources and hinders the overall trend towards cleaner and lower-carbon development. To overcome the limitations of single drones, collaborative operation of multiple drones has become an industry trend. Flexible connection and cooperation between drones with different functions enable payload sharing, task division, enhanced system stability, and increased redundancy, significantly expanding the operational boundaries of drones. However, existing research on multi-drone collaborative systems largely focuses on theoretical or control algorithm levels, with complex solutions hindering large-scale implementation.

[0003] The structural design of drones affects their flight stability, payload capacity, and scalability. Most existing drone structures are designed for single-mission tasks and cannot meet the strength and stability requirements of multi-drone collaboration. Research on flexible and multi-directionally adaptable mechanical connection structures for unit and combined drones is relatively scarce. Existing structures for drone collaboration or connection generally suffer from insufficient connection stability, cumbersome assembly and disassembly, poor environmental adaptability, and difficulty in achieving multi-directional automatic docking. This results in non-scalable payload capacity for drones, necessitating the procurement of new types of drones when existing units cannot meet mission requirements within the same mission area, leading to waste.

[0004] The design of a drone's circuitry and power supply system affects its endurance. Existing drone circuits are mostly modular designs, only meeting the needs of a single drone operating independently, lacking standardized interfaces and collaborative mechanisms for multi-drone cooperation, and unable to share power among drones. This results in a relatively fixed flight range, unable to be flexibly adjusted according to actual mission conditions, and difficult to dynamically adjust operating parameters based on swarm size, lacking comprehensive status monitoring and fault warning capabilities.

[0005] The flight control and scheduling system of unmanned aerial vehicles (UAVs) is the core system for controlling UAVs to complete their missions. At the flight control level, existing UAV collaborative control strategies and communication networks are typically based on preset fixed modes, failing to achieve intelligent and seamless switching of control strategies and communication topologies when individual UAVs freely assemble and separate, severely limiting the system's flexibility and reliability. At the scheduling system level, existing scheduling systems are mostly designed for individual UAVs, lacking the ability to efficiently allocate tasks and plan real-time paths for units and self-assembling UAV swarms.

[0006] To overcome the aforementioned shortcomings, this invention aims to provide a complete solution from bottom-level control to top-level scheduling. By integrating an autonomous adaptive master-slave control strategy, a dynamic communication topology transformation strategy, and an intelligent freight scheduling system, the UAV system of this invention can not only be flexibly reconfigured to match diverse mission requirements, but also ensure that it maintains stable, efficient, and collaborative operational capabilities in any configuration, thereby greatly expanding the application boundaries and operational efficiency of UAVs. Summary of the Invention

[0007] In view of the above-mentioned defects or improvement needs of the existing technology, the present invention provides a self-assembly unit and combined UAV system and scheduling method covering structure, circuit, flight control and scheduling system, which solves the problems of fixed payload and endurance of various single UAVs and poor versatility, and realizes the self-assembly and disassembly of multiple single UAVs, as well as the flight control and intelligent scheduling of single and combined UAVs.

[0008] To achieve the above objectives, according to one aspect of the present invention, a self-assembling unit and combination unmanned aerial vehicle system is provided, comprising: The mechanical structure of the unmanned aerial vehicle (UAV) is suitable for connecting two or more unit UAVs and is used to realize the docking between unit UAVs and the stable operation after docking. It includes the UAV outer frame, the docking locking structure between unit UAVs, and the docking guide device between unit UAVs. Unmanned aerial vehicle (UAV) circuitry systems are used to enable independent operation of a single UAV circuitry system and combined operation of circuitry systems for two or more UAVs. An inter-UAV communication routing system is used to enable real-time data communication between UAVs; Unmanned aerial vehicle (UAV) flight control system, used to realize single-UAV flight control and flight control tasks when two or more UAVs are combined; The drone dispatch system allows users to quickly set the starting point, target point, and required payload information for a task on its graphical interface. It automatically allocates several drone units to perform the task based on the transportation distance, weight, and type of materials, and remotely dispatches the drones by sending instructions through the built-in ground station.

[0009] To achieve the above objectives, according to one aspect of the present invention, a method for scheduling self-assembly unit and combined unmanned aerial vehicles (UAVs) is provided, comprising the following steps: S1: Construct a mechanical structure for connecting two or more unit drones, including the drone outer frame, docking locking structure, and docking guide device required for docking between unit drones and stable operation after docking. S2: Based on step S1, build a variable UAV circuit system to enable independent operation of a single UAV circuit system and combined operation of two or more UAV circuit systems. S3: Based on steps S1 and S2, build a UAV flight control system to realize single-aircraft flight control and flight control tasks when two or more UAVs are combined. S4: Based on steps S1, S2 and S3, establish a unit and combined UAV scheduling system based on task allocation. Users can quickly set the starting point, target point and load information required for the task on the graphical interface of the system. The system will automatically allocate several unit UAVs to perform the task according to the transportation distance and the weight and type of materials, and send instructions to them through the built-in ground station for remote scheduling, so as to realize the rapid scheduling of UAVs.

[0010] Preferably, step S1 specifically includes the following steps: S101 builds the drone frame, shell, and hardware: First, build the drone's outer frame, with its lower end serving as the drone's landing legs; then, install the drone shell, which serves as the installation space for the hardware, with the lower part of the shell enclosing the space as the battery compartment; finally, install the drone hardware, including the battery, battery management system, flight control computer, motors, propellers, ESCs, and rotors. S102 Constructing the UAV docking guidance device: Install a docking guidance device on each of the UAV frames in step S101 to guide the UAVs to dock accurately when they approach each other; the docking guidance device guides the UAV to the correct docking position through a gradually narrowing guide surface, ensuring that the UAV can dock accurately and autonomously in the air flight environment. S103 Constructing the UAV docking and locking mechanism: Install a docking and locking device base on each of the UAV frames in step S101. Each docking and locking device base provides two mounting holes for the docking and locking devices. Then, install the docking and locking devices on the docking and locking device bases. The docking and locking devices are divided into a cathode device and an anode device, which are connected to each other. The docking and locking devices have a control device connected to a motor. After the UAV is aligned with the docking guide device in step S102, it automatically locks and realizes the self-assembly function.

[0011] Preferably, the locking mechanism in step S103 is equipped with a manual unlocking device to allow for quick separation of the drone in an emergency.

[0012] Preferably, in step S101, the drone frame is made of carbon fiber composite material, the drone shell is made of rigid engineering plastic, the battery is composed of several 18650 lithium-ion batteries connected in series, and the fixed position of the rotor is confirmed by hydrodynamic simulation experiments.

[0013] Preferably, in step S103, the docking locking device uses a rotational locking method and is connected to the motor via a drive shaft; in step S102, the docking guide device adopts a conical structure.

[0014] Preferably, step S2 specifically includes the following steps: S201 Establish interface module: The interface includes the interface for connecting the positive and negative contacts of the battery compartment and the power supply system of the unit UAV in step S101; S202 Establishing a power supply module: The power supply module includes a battery pack consisting of several power batteries connected in series, which is built into the battery compartment in step S101, a step-down module connected in series with the battery pack, and a parallel module connected in series with the step-down module. S203 Establish a communication module: A point-to-point communication module is built between unit UAVs using a full-duplex serial communication architecture, and the communication architecture uses the TTL serial communication protocol.

[0015] Preferably, step S3 specifically includes the following steps: S301 Master Node Establishment and Neighbor Discovery: The ground station randomly designates a UAV as the master UAV. After the master UAV is powered on, its UART physical interfaces in the front, rear, left, and right directions are in listening mode and broadcast frames are sent at a period of 0.01 seconds to discover neighboring UAVs. S302 establishes a tree-like route: When the docking mechanism of a subordinate drone to be connected is physically aligned and locked with the master drone or an already connected subordinate drone, the corresponding communication interfaces of the two are physically connected, and the subordinate drone will immediately receive a broadcast frame from the other party; at the same time, the communication middleware of the subordinate drone will perform the following steps: a. Record the drone that sent the frame as its superior communication node; b. Reply to the lower-level drone with a confirmation frame via this physical link, which includes its own ID information; c. Initialize its own routing table and set the parent node as the default gateway; Ultimately, a tree-like communication network is formed with the main UAV as the root node; S303 Topology Update and Synchronization: After a lower-level drone successfully registers with its parent node, it generates a node join message. This message is uploaded level by level along its parent nodes until it reaches the root node, i.e., the master drone. After receiving this message, the routing management module of the master drone updates its maintained global node list and triggers the reconstruction of the control matrix. Subsequently, the master drone broadcasts a topology update message to synchronize all nodes with the latest network view. When a node leaves, its parent node will detect the link interruption and trigger a similar node leave message upload and synchronization process.

[0016] Preferably, step S4 specifically includes the following steps: The S401 establishes the attitude control algorithm for the UAV: ​​the UAV reads the current UAV motor layout, calculates the position coordinates of all motors, and then calculates the current control matrix. The drone uses a control matrix to solve a quadratic programming problem in real time and calculates the lift of all motors. The drone sends lift data as analog signals to the speed controllers of each motor for motor control, in order to achieve the goal of controlling the flight attitude of the individual drone.

[0017] Preferably, step S401 specifically involves: a single quadcopter UAV adopting a standard X-shaped layout, defining the body coordinate system. The origin is located at the center of gravity of the drone. The shaft points towards the machine head. The axis points to the right. The axes follow the right-hand rule and point downwards; the four motors are located at the four vertices of the machine coordinate system, and their planar coordinates can be expressed as:

[0018] in, Motor arm length (half-wheelbase), direction factor Corresponding to the four motor positions: front left Front right , right , back left The direction of the thrust generated by the motor is along The shaft is in negative direction (upward for positive lift). The direction of rotation of each motor is determined by the propeller type, and a steering coefficient is defined. ,in It indicates counterclockwise rotation (generating both positive and negative torque). Indicates clockwise rotation; Let the first The thrust of each motor is (Scalar) then the total lift force on the drone (along Torque in the negative direction of the axis and the three axes around the fuselage The relationship between (roll, pitch, yaw) and the thrust of each motor is as follows:

[0019] Among them, the control allocation matrix for:

[0020] The anti-torque coefficient depends on the propeller's aerodynamic characteristics; substituting the motor coordinates, we get:

[0021] For a standard X-shaped layout, an alternating steering configuration is typically used: the front left and rear right motors rotate counterclockwise. The front right and rear left motors rotate clockwise. ),Right now Then the yaw moment vector is ;at this time For a full-rank square matrix, the motor thrust distribution can be obtained by directly inverting it:

[0022] in, It is the calculated motor thrust; The desired total lift and torques on each shaft are given by the upper-level controller; the calculated thrust must meet the physical limitations of the motor. If the limit is exceeded, the thrust of all motors must be proportionally limited.

[0023] S402 establishes the attitude control algorithm for the combined UAV: ​​Before the unit UAVs begin rigid connection, one of the several unit UAVs to be connected is randomly selected as the master UAV, and the rest are slave UAVs; the master UAV reads the current UAV connection structure, calculates the position coordinates of all motors in combination with step S301, and calculates the current control matrix accordingly; the master UAV uses the control matrix to solve the quadratic programming problem in real time, calculates the lift of all motors, and then packages the lift data of all motors and broadcasts it to the other slave UAVs through the communication route; The data packets are parsed from the UAV, and the lift data is sent to the motor speed controller in the form of analog signals for motor control, so as to achieve overall attitude control after the rigid connection between the unit UAVs.

[0024] Preferably, step S402 specifically involves: the assembly consisting of... It is composed of rigidly connected individual units, with a total number of motors. The main UAV learns the positions of each UAV in the assembly through connection detection, thereby transforming the local coordinates of each motor described in S401 into coordinates in the global coordinate system (with the centroid of the assembly as the origin):

[0025] in It is a translation vector, determined by the connection position of the individual unit in the assembly; Let the first The global coordinates of each motor are The lift it generates is , turning from Indicates (counterclockwise is positive), reverse torque coefficient The total lift of the assembly depends on the aerodynamic characteristics of the propeller. and triaxial torque The relationship between (roll, pitch, yaw) and the lift of each motor is as follows:

[0026] in, Control matrix for:

[0027] Note that the rolling torque is caused by... Coordinates are generated, pitch moment is generated by The coordinates are generated in accordance with conventional definitions; because Non-square matrix ( The solution cannot be directly inverted to obtain a unique solution; to optimize energy consumption while meeting control requirements, the allocation problem is modeled as a quadratic programming problem:

[0028] in, The desired total lift and torque are given by the upper-level controller. It is a positive semidefinite weight matrix. The coefficients of the linear term, To limit the thrust of the motor; The main UAV is equipped with an embedded programming solver library, which solves the above problem in real time during each control cycle to obtain the optimal lift vector. The lift commands for each motor are then packaged and sent to the corresponding slave drone via a tree-structured communication route. The drone acts as an actuator, processing the received data packets and sending the lift data in PWM format to the speed controllers of its own motors to control the lift of each brushless motor.

[0029] S403 establishes a communication routing system between UAVs: after the random selection process before connection in step S302, data transmission during the combined flight of master and slave UAVs, and automatic topology transformation of UAV communication routes during unit connection and disconnection.

[0030] As a preferred embodiment, step S403 specifically involves: when the communication interface on one side of the main drone is not connected to other drones, it will continuously send out signals to search for drones; when other drones receive the search signal from the main drone, they will become slave drones of the main drone and establish a communication route with it. Once the master drone has identified the slave drone using the above method, the slave drone will also begin to continuously send search signals to the unconnected communication port. At this time, the drone that receives the signal and successfully establishes a communication route is considered to be a subordinate slave drone of the master drone. If a drone comes into contact with two drones that already exist in the communication system when it accesses the communication system, it will establish a communication route with the drone that first sent the search signal. The message of each slave drone joining the communication system will be transmitted back layer by layer and finally conveyed to the master drone. After receiving the signal, the master drone will incorporate the new slave drone into the flight control attitude calculation and immediately recalculate the control matrix. The master drone will then perform attitude control according to the new control matrix and send it to all slave drones for cooperation.

[0031] Preferably, step S5 specifically includes the following steps: S501: The system reads the user-set transportation task start and end points and task information, automatically executes decisions, and receives execution instructions from the drone. S502: The system sends commands to the drones performing the mission, controlling them to take off and fly to the mission starting point. The drones then execute interconnection commands, connecting layer by layer and updating the communication routes and control matrix. Subsequently, the combined drones automatically pick up the cargo and fly to the mission endpoint. S503: After completing a mission, the combined drone connectors automatically disassemble and fly to their respective charging or standby locations to await the next mission.

[0032] Preferably, the flight control attitude algorithm in step S4 is developed in C language under Linux environment, and the UAV scheduling system in step S5 is developed in Python language, while the user-end graphical interface is developed in Java and HTML language.

[0033] In summary, the technical solutions conceived by this invention have the following beneficial effects compared with the prior art: This invention relates to self-assembling unit and combined UAVs, and correspondingly designed flight control and scheduling systems, which can realize the self-assembly and automatic disassembly of unit UAVs, as well as the flight control and intelligent scheduling of single and combined multi-unit UAVs.

[0034] Specifically, the mechanical structure and circuit system of the unit UAV established by the present invention can realize the mechanical structure connection, circuit connection and power sharing between unit UAVs, so that the endurance and load capacity of the combined UAV can be flexibly adjusted according to the mission requirements, thus expanding the payload range and working scenarios of the UAV.

[0035] The unit and combined UAV system and scheduling method proposed in this invention can achieve a smooth transition between single UAV operation and multi-UAV combined operation by switching UAV flight control modes. The system can uniformly schedule unit and combined UAV swarms according to task requirements, and use a visual interface to facilitate users to monitor the operation of the UAV system. This provides a scientific basis and reliable solution for the operation of self-assembling unit and combined UAV systems in various low-altitude economic scenarios. Attached Figure Description

[0036] Figure 1 This is a schematic diagram of the appearance of a unit drone in the drone system provided by the present invention.

[0037] Figure 2 This is a schematic diagram of the battery compartment of a single unit in the unmanned aerial vehicle (UAV) system provided by the present invention.

[0038] Figure 3 A schematic diagram of the base of the docking and locking device used between unit drones in the drone system provided by the present invention.

[0039] Figure 4 The front view of the base of the docking and locking device used between unit drones in the drone system provided by the present invention.

[0040] Figure 5 This is a schematic diagram of the anode docking device in the docking device used in the UAV system provided by the present invention.

[0041] Figure 6 This is a schematic diagram of the cathode docking device in the docking device used in the UAV system provided by the present invention.

[0042] Figure 7 This is a schematic diagram of the docking locking device used in the docking device of the UAV system provided by the present invention.

[0043] Figure 8 This is a schematic diagram of the docking guide device in the docking device used in the UAV system provided by the present invention.

[0044] Figure 9 This is a schematic diagram of the docking of two unit drones in the drone system provided by the present invention.

[0045] Figure 10 This is a schematic diagram of the linear docking of four drones in the drone system provided by the present invention.

[0046] Figure 11 This is a schematic diagram of four UAVs in a circular docking system provided by the present invention.

[0047] Figure 12 The circuit diagram of the parallel module in the unit drone of the UAV system provided by the present invention.

[0048] Figure 13 This is a schematic diagram of a unit UAV circuit system provided by the present invention.

[0049] Figure 14 The process of establishing communication routes for a unit UAV system provided by the present invention.

[0050] Figure 15 The working process of the drone scheduling system provided by the present invention. Detailed Implementation

[0051] 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. It should be understood that the specific embodiments described herein are merely illustrative and not intended to limit the invention. Furthermore, the technical features involved in the various embodiments of this invention described below can be combined with each other as long as they do not conflict with each other.

[0052] like Figures 1-15 As shown: This embodiment provides a self-assembling unit and combination unmanned aerial vehicle system, including: The mechanical structure of the unmanned aerial vehicle (UAV) is suitable for connecting two or more unit UAVs and is used to realize the docking between unit UAVs and the stable operation after docking. It includes the UAV outer frame, the docking locking structure between unit UAVs, and the docking guide device between unit UAVs. Unmanned aerial vehicle (UAV) circuitry systems are used to enable independent operation of a single UAV circuitry system and combined operation of circuitry systems for two or more UAVs. An inter-UAV communication routing system is used to enable real-time data communication between UAVs; Unmanned aerial vehicle (UAV) flight control system, used to realize single-UAV flight control and flight control tasks when two or more UAVs are combined; The drone dispatch system allows users to quickly set the starting point, target point, and required payload information for a task on its graphical interface. It automatically allocates several drone units to perform the task based on the transportation distance, weight, and type of materials, and remotely dispatches the drones by sending instructions through the built-in ground station.

[0053] The scheduling method based on the above-mentioned self-assembling unit and combined UAV system includes the following steps: S1: Construct a mechanical structure for connecting two or more unit drones, including the drone outer frame, docking locking structure, and docking guide device required for docking between unit drones and stable operation after docking. Step S1 specifically includes the following steps: S101 builds the drone frame, shell, and hardware: First, build the drone's outer frame, with its lower end serving as the drone's landing legs; then, install the drone shell, which serves as the installation space for the hardware, with the lower part of the shell enclosing the space as the battery compartment; finally, install the drone hardware, including the battery, battery management system, flight control computer, motors, propellers, ESCs, and rotors. like Figure 1 The outer frame of the drone is constructed, including two perpendicularly intersecting equal-length tubes 1, and four equal-length tubes 2 connected to the four ends of the tubes and perpendicular to the plane formed by the two intersecting tubes; wherein, the lower end of the tubes 2 serves as the landing legs of the drone; the tubes are made of carbon fiber composite material. The drone's outer shell is then installed. Made of rigid engineering plastic, the outer shell serves as the mounting space for the hardware and is formed by joining an upper shell 3 and a lower shell 4. The space enclosed by the lower shell serves as the battery compartment, which features an automatic battery swapping function that interacts with external mechanical devices. Figure 2 As shown, the battery compartment consists of a battery pack 41, a battery bracket 42, a slide rail 43, an electrode interface 44, a magnetic baffle 45, and a battery compartment cover 46. The battery bracket 42 has sliding structures on both sides, allowing it to slide in and out in a fixed direction after contacting the slide rail 43. After the battery bracket 42 slides into the slide rail 43, the magnetic piece on its inner side contacts and adheres to the magnetic baffle, thus securing the battery.

[0054] Finally, the drone hardware is installed, including battery 41, battery management system, flight control computer, motor 5, propellers 6, and ESC. The battery management system, flight control computer, and ESC are housed within the drone's outer shell. Motor 5 is fixed to tube 1 by clamp 100, and propellers 6 are mounted on the motor 5's shaft. Signal cables required for drone installation are routed within the hollow cavities of tubes 1 and 2. The battery consists of several 18650 lithium-ion batteries connected in series. The rotor's fixed position was confirmed through fluid dynamics simulation experiments to ensure that no flow field disturbances cause docking instability during inter-drone docking.

[0055] S102 Constructing the UAV docking guidance device: Install a docking guidance device on each of the UAV frames in step S101 to guide the UAVs to dock accurately when they approach each other; the docking guidance device guides the UAV to the correct docking position through a gradually narrowing guide surface, ensuring that the UAV can dock accurately and autonomously in the air flight environment. like Figure 1 A docking guide device 10 is installed on each of the four vertical, equal-length pipes 2 of the UAV using pipe clamps 100 to guide the UAV to dock accurately. The docking guide device 10 adopts a conical guide structure, consisting of an anode guide 101 and a cathode guide 102. Figure 8 The guiding structure guides the two drones to the correct docking position through the guide surface of the anode guide 101, which gradually shrinks as it approaches the cathode guide 102, ensuring that the drones can dock accurately in the air.

[0056] To achieve the multidirectional connectivity of the UAV unit in this invention, the docking locking device 8 is designed with the following topology: the mounting hole directions of the two docking locking device bases 7 on any diagonal direction of the UAV are the same. For example, the positions of the four docking locking devices 8 on the same diagonal are: two cathode docking devices 81 on top and two anode docking devices 82 on the bottom. Similarly, the positions of the four docking locking devices 8 arranged on the other diagonal are: two cathode docking devices 81 on the bottom and two anode docking devices 82 on top. This complementary structure enables the unit and the combined UAV to dock with other UAVs from various directions in space.

[0057] like Figure 9 In one embodiment, two drones need to dock. With one drone 1 fixed in place and the other drone 2 positioned in various directions (front, back, left, right) of drone 1, complementary docking can be achieved simply by controlling the rotation of drone 2 to make any docking surface parallel. For example... Figure 10 and Figure 11 In another embodiment, four unit drones need to dock. This can be achieved by first docking the drones in pairs, and then controlling two dual-drone assemblies to dock in the same manner as the two drones. The four-drone assembly can be either 1×4 or 2×2 in shape. Therefore, the docking combinations of four or more unit drones described in this invention are multidirectional and customizable.

[0058] S103 Constructing the UAV docking and locking mechanism: Install a docking and locking device base on each of the UAV frames in step S101. Each docking and locking device base provides two mounting holes for the docking and locking devices. Then, install the docking and locking devices on the docking and locking device bases. The docking and locking devices are divided into a cathode device and an anode device, which are connected to each other. The docking and locking devices have a control device connected to a motor. After the UAV is aligned with the docking guide device in step S102, it automatically locks and realizes the self-assembly function.

[0059] like Figure 1 and Figure 3 A docking locking device base 7 is installed on four vertical, equal-length pipes of the UAV using pipe clamps 100. The pipe clamps have threaded holes that match the threaded holes 71 on the docking locking device base 7. Each docking locking base provides two UAV docking contact planes at a 90-degree angle and four mounting holes for the docking locking device. Two of these are cathode mounting positions 72, and two are anode mounting positions 73, each with through holes for fixation.

[0060] A docking locking device 8 is installed on the base of the docking locking device, and locking is achieved by rotation. It is connected to a motor via a drive shaft. Specifically, the docking locking device consists of a cathode device 81 and an anode device 82, with one cathode device 81 and one anode device 82 installed on each docking contact surface. Figure 5 , Figure 6 The diagram illustrates the specific structures of the anode docking device 82 and the cathode docking device 81. The anode docking device consists of a bushing 821, a rotating shaft 822, an internal hexagonal hole 823, an upper crossbar 824, a lower crossbar 825, and an anode mounting hole 826. The cathode docking device 81 consists of a docking hole 811, a base 812, and a cathode mounting hole 813.

[0061] like Figure 7As shown, the docking locking device includes a mechanical locking function to ensure that the UAVs will not separate during flight and has sufficient resistance to bending moments. The upper part of the anode docking device 82 is provided with an internal hexagonal hole 823, which can match the servo motor 9 on the UAV. After engaging with the internal hexagonal hole 823, the servo motor 9 can drive the rotating shaft 822 of the anode docking device 82 to rotate. The rotating shaft 822 has two crossbars 824, which match the grooves at the bottom of the bushing 821. When the rotating shaft 822 rotates, the upper crossbar 824 rotates, achieving a limiting function. The lower crossbar 825 of the rotating shaft 822 matches the docking hole 811 of the cathode docking device 81. When the rotating shaft 822 rotates, it can achieve locking inside the anode docking device 82 and the cathode docking device 81. The anode docking device 82 and the servo motor 9 are connected through the internal hexagonal hole 823, and automatically rotate and lock after the UAVs are docked in place, improving operational convenience. The locking mechanism is equipped with a manual unlocking device for quick separation of the drone in an emergency.

[0062] S2: Based on step S1, build a variable UAV circuit system to enable independent operation of a single UAV circuit system and combined operation of two or more UAV circuit systems. Based on the PX4 open-source flight controller and MavLink protocol, and building upon the mechanical structure of drones connecting two or more unit drones as described in step S1, a system is constructed as follows: Figure 13 The unit UAV circuit system shown can realize the independent operation of a single UAV circuit system and the combined operation of two or more UAV circuit systems.

[0063] Step S2 specifically includes the following steps: S201 Establish interface module: The interface includes the positive and negative contact interface for connecting the battery compartment and the unit UAV power supply system in step S101, and a magnetic contact circuit connector between the unit UAV circuits, which is composed of protective components such as integrated fuses and Schottky diodes to prevent reverse charging, system short circuit overload, and electrostatic damage. S202 Establishing a power supply module: The power supply module includes a battery pack consisting of several power batteries connected in series, which is built into the battery compartment in step S101, a step-down module connected in series with the battery pack, and a parallel module connected in series with the step-down module. In this embodiment, the power supply module includes: a battery pack consisting of four 18650 lithium-ion batteries connected in series and built into the battery compartment; a step-down module connected in series with the battery pack, providing a stable 12V voltage with an operating range of 14V to 24V; and a Schottky diode-based adapter connected in series with the step-down module to provide a 12V voltage output. Figure 12 The parallel module shown.

[0064] S203 Establishes a Communication Module: A point-to-point communication module is built between unit UAVs using a full-duplex serial communication architecture. The communication architecture uses the TTL serial communication protocol. To support the communication hardware requirements between unit UAVs, a point-to-point communication module based on a UART interface, TTL level, and MavLink protocol is adopted.

[0065] S3: Based on steps S1 and S2, establish a communication routing system between unit UAVs to realize real-time data communication between UAVs; Step S3 specifically includes the following steps: S301 Master Node Establishment and Neighbor Discovery: The ground station randomly designates a specific UAV as the master UAV. After the master UAV is powered on, its UART physical interfaces in the four directions (front, back, left, and right) are in listening mode. For the corresponding port of the physical interface that is not connected, its driver layer will send a broadcast frame every 0.01 seconds to discover neighboring UAVs. This frame contains the master UAV ID and port number.

[0066] S302 establishes a tree-like route: When the docking mechanism of a subordinate drone to be connected is physically aligned and locked with the master drone or an already connected subordinate drone, the corresponding communication interfaces of the two are physically connected, and the subordinate drone will immediately receive a broadcast frame from the other party; at the same time, the communication middleware of the subordinate drone will perform the following steps: a. Record the drone that sent the frame as its superior communication node; b. Reply to the lower-level drone with a confirmation frame via this physical link, which includes its own ID information; c. Initialize its own routing table and set the parent node as the default gateway; This process is recursive, such as... Figure 14 As shown, a multi-machine interconnection ultimately forms a tree-like communication network with the main UAV as the root node.

[0067] S303 Topology Update and Synchronization: After a lower-level drone successfully registers with its parent node, it generates a node join message. This message is uploaded level by level along its parent nodes until it reaches the root node, i.e., the master drone. After receiving this message, the routing management module of the master drone updates its maintained global node list and triggers the reconstruction of the control matrix. Subsequently, the master drone broadcasts a topology update message to synchronize all nodes with the latest network view. When a node leaves, its parent node will detect the link interruption and trigger a similar node leave message upload and synchronization process.

[0068] S4: Based on step S3, build a UAV flight control system to realize single-aircraft flight control and flight control tasks when two or more UAVs are combined. Step S4 specifically includes the following steps: The S401 establishes the attitude control algorithm for the UAV: ​​the UAV reads the current UAV motor layout, calculates the position coordinates of all motors, and then calculates the current control matrix. The attitude control algorithm is developed in C language under Linux, meaning that a dynamic module structure tree exists in real time within the main UAV flight control system. This tree structure is updated whenever a UAV joins or leaves. Each node in the tree records the global coordinates of a UAV unit and the local coordinates of its four motors. Assuming the connected system consists of N UAVs, there are a total of 4N motors. The main UAV maintains a control matrix based on the two-dimensional coordinates of all motors. The specific elements of the control matrix are determined by the motor positions and the rotor dynamics model.

[0069] Taking a single quadcopter drone as an example, a single quadcopter drone adopts a standard X-shaped layout, defining the body coordinate system. The origin is located at the center of gravity of the drone. The shaft points towards the machine head. The axis points to the right. The axes follow the right-hand rule and point downwards; the four motors are located at the four vertices of the machine coordinate system, and their planar coordinates can be expressed as:

[0070] in, Motor arm length (half-wheelbase), direction factor Corresponding to the four motor positions: front left Front right , right , back left The direction of the thrust generated by the motor is along The shaft is in negative direction (upward for positive lift). The direction of rotation of each motor is determined by the propeller type, and a steering coefficient is defined. ,in It indicates counterclockwise rotation (generating both positive and negative torque). Indicates clockwise rotation; Let the first The thrust of each motor is (Scalar) then the total lift force on the drone (along Torque in the negative direction of the axis and the three axes around the fuselage The relationship between (roll, pitch, yaw) and the thrust of each motor is as follows:

[0071] The parameters are as follows: motor arm length

[0072] Anti-torque coefficient

[0073] Motor steering configuration: (Right front counterclockwise) (clockwise from left) (Left front clockwise) (Right rear counterclockwise) Thrust Limitation: ,

[0074] Based on the above parameters, the control allocation matrix is:

[0075] Calculate its inverse matrix:

[0076] Assume the desired control output of the current attitude controller is: Total lift

[0077] Rolling torque

[0078] Pitch moment

[0079] Yaw moment

[0080] The motor thrust command is then:

[0081] All thrust values ​​are within permissible limits. The flight controller converts these four thrust values ​​into corresponding PWM duty cycles and sends them to the electronic speed controller (ESC) to achieve the desired attitude. This algorithm executes every 2.5ms in the embedded flight controller, meeting real-time control requirements.

[0082] The UAV uses a control matrix to solve a quadratic programming problem in real time and calculates the lift of all motors; that is, within each 2.5ms control cycle, the main UAV runs the attitude controller to calculate the required output speed of each motor in the connected body to maintain the desired attitude and position of the connected body.

[0083] The master drone segments the slave drones according to their IDs, based on the calculated required output speed for each motor. This data is encapsulated in a custom MAVLink message. The message is broadcast through the communication routing tree established in S3. Upon receiving the message, each slave drone extracts its own lift data, converts it into a PWM signal, and sends it directly to the electronic speed controller.

[0084] The drone sends lift data to the speed controllers of each motor in the form of analog signals for motor control, in order to achieve the goal of controlling the flight attitude of the individual drone. S402 establishes the attitude control algorithm for the combined UAV: ​​Before the unit UAVs begin rigid connection, one of the several unit UAVs to be connected is randomly selected as the master UAV, and the rest are slave UAVs; the master UAV reads the current UAV connection structure, calculates the position coordinates of all motors in combination with step S301, and calculates the current control matrix accordingly; the master UAV uses the control matrix to solve the quadratic programming problem in real time, calculates the lift of all motors, and then packages the lift data of all motors and broadcasts it to the other slave UAVs through the communication route; For a specific case of X-shaped quadcopter drones forming a 2×2 grid, the following parameters are set: each drone adopts a standard X-shaped layout, and the motor arm length (half-wheelbase) is [not specified]. That is, the coordinates of the four motors in the UAV's body coordinate system are as follows:

[0085] The four drones are arranged in a 2×2 grid, with the center-to-center distance between adjacent drones being... The origin of the overall coordinate system is located at the geometric center of the composite structure. The center positions of each UAV are:

[0086] To ensure overall yaw controllability, the motor steering configuration of each drone employs a symmetrical design: the diagonal motors of drones 1 and 4 rotate in the same direction, while the motors of drones 2 and 3 rotate in opposite directions, achieving overall anti-torque balance. Specifically, a steering coefficient is defined. ,in It indicates counterclockwise rotation (generating both positive and negative torque). Indicates clockwise rotation. Anti-torque coefficient.

[0087] Therefore, the global coordinates of all 16 motors can be obtained by superimposing the center coordinates of the UAV with the local coordinates. For example, the global coordinates of motor 1 of UAV 1 are: And so on. Record the number... The global coordinates of each motor are The steering coefficient is Then the control matrix The column vectors are:

[0088] This matrix represents the motor thrust vector. Mapped to the desired total force and torque ,Right now:

[0089] The motor thrust distribution problem is modeled as a quadratic programming problem. With the objective of minimizing overall energy consumption, i.e., minimizing the sum of squared thrust, the optimization problem can be written as:

[0090] The upper and lower limits of thrust are taken as normalized values. , (Corresponding to the minimum and maximum thrust of the motor). This problem is a typical convex quadratic programming problem with 16 variables, 4 equality constraints, and 32 inequality constraints. An efficient solver, qpOASES, is used for online solving. The optimal motor thrust vector is obtained by calculating once every 2.5ms control cycle. This allows us to calculate the required rotational speed of each motor within the combined UAV.

[0091] The master UAV is segmented according to the ID of the slave UAVs based on the calculated required output speed of each motor. This data is encapsulated in a custom MAVLink message. The message is broadcast through the communication routing tree established in S3. After receiving the message, each slave UAV extracts its own lift data, converts it into a PWM signal, and sends it directly to the electronic speed controller. The slave UAV parses the data packet and sends the lift data as an analog signal to the motor speed controller for motor control, thereby achieving overall attitude control after the rigid connection between the unit UAVs. S403 establishes a communication routing system between UAVs: after the random selection process before connection in step S302, data transmission during the combined flight of master and slave UAVs, and automatic topology transformation of UAV communication routes during unit connection and disconnection.

[0092] When the communication interface on one side of the master drone is not connected to other drones, it will continuously send out signals to search for drones. When other drones receive the search signal from the master drone, they will become slave drones of the master drone and establish a communication route with it. Once the master drone has identified the slave drone using the above method, the slave drone will also begin to continuously send search signals to the unconnected communication port. At this time, the drone that receives the signal and successfully establishes a communication route is considered to be a subordinate slave drone of the master drone. If a drone comes into contact with two drones that already exist in the communication system when it accesses the communication system, it will establish a communication route with the drone that first sent the search signal. The message of each slave drone joining the communication system will be transmitted back layer by layer and finally conveyed to the master drone. After receiving the signal, the master drone will incorporate the new slave drone into the flight control attitude calculation and immediately recalculate the control matrix. The master drone will then perform attitude control according to the new control matrix and send it to all slave drones for cooperation.

[0093] S5: Based on step S4, establish the working process as follows: Figure 15 The unit and combined UAV scheduling system based on task allocation shown is developed using Python, while the user-end graphical interface is developed using Java and HTML. Users can quickly set the starting point, target point, and required payload information of the task on the graphical interface of the system. The system will automatically allocate several unit UAVs to perform the task according to the transportation distance, as well as the weight and type of materials, and send instructions to them through the built-in ground station for remote scheduling, so as to realize the rapid scheduling of UAVs.

[0094] Step S5 specifically includes the following steps: S501: The system reads the user-set transportation task start and end points and task information, automatically executes decisions, and receives execution instructions from the drone. If a user's ground station UI sets up task T, task T includes: origin A, destination B, and cargo weight G. The scheduling server executes the following decision-making process: a. Quantity decision: Considering redundancy and flight stability, calculate the minimum number of drones X required based on cargo weight G, starting point A and ending point B; b. Drone selection decision: Query the database to filter out X drones that are closest to point A, have a battery level greater than 50%, and are in an idle state; c. Path planning: Plan safe assembly routes for each of the X UAVs from their current location to point A, and transport routes from A to B.

[0095] S502: The system sends commands to the drones performing the mission, controlling them to take off and fly to the mission starting point. The drones then execute interconnection commands, connecting layer by layer and updating the communication routes and control matrix. Subsequently, the combined drones automatically pick up the cargo and fly to the mission endpoint. In this embodiment, the ground station randomly selects and sends detailed mission instruction packets to the master UAV via the data transmission network. Upon receiving the instructions, the master UAV establishes a temporary mission grouping communication link with the other X-1 UAVs. The X UAVs autonomously fly to point A and form a formation over point A. Subsequently, under the coordination of the master UAV, each UAV executes an autonomous aerial docking procedure guided by the docking mechanism, forming a multi-UAV connector. After successful docking, the master UAV recalculates the control matrix and controls the connector to land at point A, automatically grabbing / loading cargo of weight G using a robotic arm or hook. Finally, the connector, carrying the cargo, flies together to the destination B.

[0096] S503: After completing a mission, the combined drone connectors automatically disassemble and fly to their respective charging or standby locations to await the next mission.

[0097] In this embodiment, after reaching point B and unloading the cargo, the ground station sends a disband command to the main UAV. The connecting components separate in an orderly manner, and each UAV resumes its individual flight mode. Each UAV, based on its built-in charging station location map and remaining battery power, autonomously decides whether to return to a charging station to recharge or fly to the nearest standby area to await a new mission. Simultaneously, its status is updated back to the ground station database.

[0098] Those skilled in the art will readily understand that the above description is merely a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of the present invention should be included within the scope of protection of the present invention.

Claims

1. A self-assembling unit and combination unmanned aerial vehicle system, characterized in that, include: The mechanical structure of the unmanned aerial vehicle (UAV) is suitable for connecting two or more unit UAVs and is used to realize the docking between unit UAVs and the stable operation after docking. It includes the UAV outer frame, the docking locking structure between unit UAVs, and the docking guide device between unit UAVs. Unmanned aerial vehicle (UAV) circuitry systems are used to enable independent operation of a single UAV circuitry system and combined operation of circuitry systems for two or more UAVs. An inter-UAV communication routing system is used to enable real-time data communication between UAVs; Unmanned aerial vehicle (UAV) flight control system, used to realize single-UAV flight control and flight control tasks when two or more UAVs are combined; The drone dispatch system allows users to quickly set the starting point, target point, and required payload information for a task on its graphical interface. It automatically allocates several drone units to perform the task based on the transportation distance, weight, and type of materials, and remotely dispatches the drones by sending instructions through the built-in ground station.

2. A method for scheduling self-assembling unit and combined UAVs, characterized in that, The self-assembly unit and combined unmanned aerial vehicle system according to claim 1 includes the following steps: S1: Construct a mechanical structure for connecting two or more unit drones, including the drone outer frame, docking locking structure, and docking guide device required for docking between unit drones and stable operation after docking. S2: Based on step S1, build a variable UAV circuit system to enable independent operation of a single UAV circuit system and combined operation of two or more UAV circuit systems. S3: Based on steps S1 and S2, establish a communication routing system between unit UAVs to realize real-time data communication between UAVs; S4: Based on step S3, build a UAV flight control system to realize single-aircraft flight control and flight control tasks when two or more UAVs are combined. S5: Based on step S4, establish a unit and combined UAV scheduling system based on task allocation. Users can quickly set the starting point, target point and load information required for the task on the graphical interface of the system. The system will automatically allocate several unit UAVs to perform the task according to the transportation distance and the weight and type of materials, and send instructions to them through the built-in ground station for remote scheduling, so as to realize the quick scheduling of UAVs.

3. The self-assembly unit and combined UAV scheduling method as described in claim 2, characterized in that, Step S1 specifically includes the following steps: S101 builds the drone frame, shell, and hardware: First, build the drone's outer frame, with its lower end serving as the drone's landing legs; then, install the drone shell, which serves as the installation space for the hardware, with the lower part of the shell enclosing the space as the battery compartment; finally, install the drone hardware, including the battery, battery management system, flight control computer, motors, propellers, ESCs, and rotors. S102 Constructing the UAV docking guidance device: Install a docking guidance device on each of the UAV frames in step S101 to guide the UAVs to dock accurately when they approach each other; the docking guidance device guides the UAV to the correct docking position through a gradually narrowing guide surface, ensuring that the UAV can dock accurately and autonomously in the air flight environment. S103 Constructing the UAV docking and locking mechanism: Install a docking and locking device base on each of the UAV frames in step S101. Each docking and locking device base provides two mounting holes for the docking and locking devices. Then, install the docking and locking devices on the docking and locking device bases. The docking and locking devices are divided into a cathode device and an anode device, which are connected to each other. The docking and locking devices have a control device connected to a motor. After the UAV is aligned with the docking guide device in step S102, it automatically locks and realizes the self-assembly function.

4. The self-assembling unit and combined UAV scheduling method as described in claim 3, characterized in that, In step S101, the drone frame is made of carbon fiber composite material, the drone shell is made of rigid engineering plastic, the battery is composed of lithium-ion batteries connected in series, and the fixed position of the rotor is confirmed by fluid dynamics simulation experiments; in step S102, the docking guide device adopts a conical structure; in step S103, the docking locking device is locked by rotation and is connected to the motor through a drive shaft; and in step S103, the docking locking mechanism is equipped with a manual unlocking device so as to quickly separate the drone in an emergency.

5. A method for scheduling self-assembling unit and combined UAVs as described in claim 3 or 4, characterized in that, Step S2 specifically includes the following steps: S201 Establish interface module: The interface includes the interface for connecting the positive and negative contacts of the battery compartment and the power supply system of the unit UAV in step S101; S202 Establishing a power supply module: The power supply module includes a battery pack consisting of several power batteries connected in series, which is built into the battery compartment in step S101, a step-down module connected in series with the battery pack, and a parallel module connected in series with the step-down module. S203 Establish a communication module: A point-to-point communication module is built between unit UAVs using a full-duplex serial communication architecture, and the communication architecture uses the TTL serial communication protocol.

6. The method for scheduling self-assembling unit and combined UAVs as described in claim 5, characterized in that, Step S3 specifically includes the following steps: S301 Master Node Establishment and Neighbor Discovery: The ground station randomly designates a UAV as the master UAV. After the master UAV is powered on, its UART physical interfaces in the front, rear, left, and right directions are in listening mode and broadcast frames are sent at a period of 0.01 seconds to discover neighboring UAVs. S302 establishes a tree-like route: When the docking mechanism of a subordinate drone to be connected is physically aligned and locked with the master drone or an already connected subordinate drone, the corresponding communication interfaces of the two are physically connected, and the subordinate drone will immediately receive a broadcast frame from the other party; at the same time, the communication middleware of the subordinate drone will perform the following steps: a. Record the drone that sent the frame as its superior communication node; b. Reply to the lower-level drone with a confirmation frame via this physical link, which includes its own ID information; c. Initialize its own routing table and set the parent node as the default gateway; Ultimately, a tree-like communication network is formed with the main UAV as the root node; S303 Topology Update and Synchronization: After a lower-level drone successfully registers with its parent node, it generates a node join message. This message is uploaded level by level along its parent nodes until it reaches the root node, i.e., the master drone. After receiving this message, the routing management module of the master drone updates its maintained global node list and triggers the reconstruction of the control matrix. Subsequently, the master drone broadcasts a topology update message to synchronize all nodes with the latest network view. When a node leaves, its parent node will detect the link interruption and trigger a similar node leave message upload and synchronization process.

7. The self-assembly unit and combined UAV scheduling method as described in claim 6, characterized in that, Step S4 specifically includes the following steps: The S401 establishes the attitude control algorithm for the UAV: ​​the UAV reads the current UAV motor layout, calculates the position coordinates of all motors, and then calculates the current control matrix. The drone uses a control matrix to solve a quadratic programming problem in real time and calculates the lift of all motors. The drone sends lift data to the speed controllers of each motor in the form of analog signals for motor control, in order to achieve the goal of controlling the flight attitude of the individual drone. S402 establishes the attitude control algorithm for the combined UAV: ​​Before the unit UAVs begin rigid connection, one of the several unit UAVs to be connected is randomly selected as the master UAV, and the rest are slave UAVs; the master UAV reads the current UAV connection structure, calculates the position coordinates of all motors in combination with step S301, and calculates the current control matrix accordingly; the master UAV uses the control matrix to solve the quadratic programming problem in real time, calculates the lift of all motors, and then packages the lift data of all motors and broadcasts it to the other slave UAVs through the communication route; The data packets are parsed from the UAV, and the lift data is sent to the motor speed controller in the form of analog signals for motor control, so as to achieve overall attitude control after the rigid connection between the unit UAVs. S403 establishes a communication routing system between UAVs: after the random selection process before connection in step S302, data transmission during the combined flight of master and slave UAVs, and automatic topology transformation of UAV communication routes during unit connection and disconnection.

8. The self-assembly unit and combined UAV scheduling method as described in claim 7, characterized in that, Step S403 specifically involves: when the communication interface on one side of the main UAV is not connected to other UAVs, it will continuously send out signals to search for UAVs. When other drones receive the search signal from the master drone, they will become slave drones of the master drone and establish a communication route with it. Once the master drone has identified the slave drone using the above method, the slave drone will also begin to continuously send search signals to the unconnected communication port. At this time, the drone that receives the signal and successfully establishes a communication route is considered to be a subordinate slave drone of the master drone. If a drone comes into contact with two drones that already exist in the communication system when it accesses the communication system, it will establish a communication route with the drone that first sent the search signal. The message of each slave drone joining the communication system will be transmitted back layer by layer and finally conveyed to the master drone. After receiving the signal, the master drone will incorporate the new slave drone into the flight control attitude calculation and immediately recalculate the control matrix. The master drone will then perform attitude control according to the new control matrix and send it to all slave drones for cooperation.

9. A method for scheduling self-assembling unit and combined UAVs as described in claim 8, characterized in that, Step S5 specifically includes the following steps: S501: The system reads the user-set transportation task start and end points and task information, automatically executes decisions, and receives execution instructions from the drone. S502: The system sends commands to the drones performing the mission, controlling them to take off and fly to the mission starting point. The drones then execute interconnection commands, connecting layer by layer and updating the communication routes and control matrix. Subsequently, the combined drones automatically pick up the cargo and fly to the mission endpoint. S503: After completing a mission, the combined drone connectors automatically disassemble and fly to their respective charging or standby locations to await the next mission.

10. A method for scheduling self-assembling unit and combined UAVs as described in claim 9, characterized in that, In step S4, the flight control attitude algorithm is developed in C language under Linux environment, and in step S5, the UAV scheduling system is developed in Python language. The user-end graphical interface is developed in Java and HTML language.

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