An Unmanned Aerial Vehicle Fixed-Point Delivery Device and Operation Method

Abstract

The present invention relates to the technical field of intelligent unmanned aerial vehicles, and particularly to a fixed-point delivery device and operation method for an unmanned aerial vehicle; Technical problem: The attitude pre-adjustment of the fixed-point delivery device for an unmanned aerial vehicle in the prior art is insufficient, the delivery control is inaccurate, and the attitude feedback and adjustment mechanism is imperfect; Technical solution: A fixed-point delivery device and operation method for an unmanned aerial vehicle, including an unmanned aerial vehicle frame, an integrated sensor module, a signal transmission module, a bracket, and a delivery component; The present invention precisely pre-adjusts the attitude of the unmanned aerial vehicle through a ground control station to ensure that the unmanned aerial vehicle is in the best stable state before delivery. According to the real-time position and attitude data of the unmanned aerial vehicle, the opening and closing timing and force of the electric telescopic rod and the electromagnetic block are dynamically adjusted to improve the accuracy and reliability of delivery. When the unmanned aerial vehicle has an attitude deviation, the deviation can be corrected through the attitude feedback and adjustment mechanism to ensure that the unmanned aerial vehicle can fly stably and complete the subsequent delivery task.

Description

Technical Field

[0001] The present invention relates to the technical field of intelligent unmanned aerial vehicles, and particularly to an unmanned aerial vehicle fixed-point delivery device and an operation method thereof. Background Art

[0002] Today, with the increasing maturity of unmanned aerial vehicle technology, unmanned aerial vehicle fixed-point delivery devices have shown broad application prospects in many fields such as agricultural sowing, emergency rescue material delivery, and environmental monitoring; traditional unmanned aerial vehicle fixed-point delivery technologies mainly rely on the operation experience of pilots and the built-in navigation systems of unmanned aerial vehicles, but in actual applications, there are still a series of challenges; especially in complex environments or delivery tasks with high-precision requirements, the attitude control, delivery accuracy, and stability during the delivery process of unmanned aerial vehicles become key technical problems; specific problems include:

[0003] 1. Insufficient attitude pre-adjustment: In the existing technology, although some unmanned aerial vehicles will perform basic attitude calibration before takeoff, they often lack precise pre-adjustment for specific delivery tasks; this results in the fact that the unmanned aerial vehicle may not reach the best stable state before delivery, thereby affecting the delivery accuracy and the stability of the unmanned aerial vehicle itself; the adjustment of the pitch angle, roll angle, and yaw angle usually depends on the empirical judgment of the operator, lacking automated and precise adjustment means, making it difficult for the unmanned aerial vehicle to accurately point to the delivery target;

[0004] 2. Imprecise delivery control: When the unmanned aerial vehicle approaches the delivery point, the delivery control in the existing technology often relies on simple switch control or timing control, lacking the ability to dynamically adjust according to the real-time position and attitude of the unmanned aerial vehicle, which easily causes the delivery object to deviate from the predetermined position and affects the delivery effect;

[0005] 3. Imperfect attitude feedback and adjustment mechanism: During the delivery process, the monitoring of the attitude change of the unmanned aerial vehicle usually relies on the data of a single sensor, lacking the ability of multi-sensor fusion and real-time data analysis; the attitude feedback and adjustment mechanism has a slow response speed and the control algorithm is not precise enough, resulting in the fact that it is difficult for the unmanned aerial vehicle to correct the attitude deviation in time when the attitude deviation occurs, affecting the stability of the delivery process and the execution of subsequent tasks;

[0006] Therefore, in view of the above problems, a fixed-point delivery device and an operation method for an unmanned aerial vehicle are proposed. The ground control station precisely pre-adjusts the attitude of the unmanned aerial vehicle to ensure that the unmanned aerial vehicle is in the best stable state before delivery. According to the real-time position and attitude data of the unmanned aerial vehicle, the opening and closing timing and force of the electric telescopic rod and the electromagnetic block are dynamically adjusted to improve the delivery accuracy and reliability. When the unmanned aerial vehicle has an attitude deviation, the deviation can be corrected through the attitude feedback and adjustment mechanism to ensure that the unmanned aerial vehicle can fly stably and complete the subsequent delivery task. Summary of the Invention

[0007] To overcome the problems of insufficient attitude pre-adjustment, inaccurate delivery control, and imperfect attitude feedback and adjustment mechanism of the UAV fixed-point delivery device under the existing technology.

[0008] The technical solution of the present invention is: a UAV fixed-point delivery device, including a UAV frame, an integrated sensor module, a signal transmission module, a bracket, and a delivery component; an integrated sensor module is arranged above the UAV frame, a signal transmission module is arranged above the UAV frame, a bracket is arranged below the UAV frame, and a delivery component is arranged below the UAV frame; the delivery component includes an electric telescopic rod, an electromagnetic block, a metal connecting block, and a hanging ring; an electric telescopic rod is arranged below the UAV frame, an electromagnetic block is arranged at one end of the electric telescopic rod, a metal connecting block is arranged below the electromagnetic block, and a hanging ring is arranged below the metal connecting block.

[0009] Preferably, the integrated sensor module is used to measure and describe the attitude and heading of the UAV in real time, providing precise navigation information for fixed-point delivery; the signal transmission module is used to transmit data instruction signals between the UAV and the ground control station; the bracket is used to support the UAV during takeoff and landing; the hanging ring can hold the delivery object to be delivered; the electric telescopic rod receives a control instruction, and the electric telescopic rod expands and contracts according to the calculated expansion and contraction amount to move the delivery object to the delivery position; when the delivery object reaches the predetermined delivery position, an activation instruction is sent to the electromagnetic block to make it instantly lose magnetism and release the metal connecting block, thereby releasing the delivery object.

[0010] Preferably, the integrated sensor module includes a gyroscope, an accelerometer, and a magnetometer; the gyroscope is used to measure the angular velocity of the UAV around its three main axes, namely the roll axis, the pitch axis, and the yaw axis, so as to provide information on the change of the attitude angle of the UAV; the accelerometer is used to measure the linear acceleration of the UAV in three axial directions, namely front-back, left-right, and up-down, as well as the components of the gravitational acceleration in the UAV coordinate system; the magnetometer is used to measure the three components of the geomagnetic field in the UAV coordinate system to determine the heading angle of the UAV, that is, the yaw angle; the data of the magnetometer is combined with the data of the gyroscope and the accelerometer to describe the attitude and heading of the UAV, providing precise navigation information for fixed-point delivery.

[0011] Preferably, the signal transmission module is arranged above the UAV frame and is electrically connected to the integrated sensor module and the delivery component; the signal transmission module includes:

[0012] A data receiving unit, used to receive real-time data from the integrated sensor module, including but not limited to the angular velocity data measured by the gyroscope, the linear acceleration and gravitational acceleration data measured by the accelerometer, and the geomagnetic field data measured by the magnetometer;

[0013] A data processing unit, connected to the data receiving unit, is used to preprocess the received data, including but not limited to data verification, format conversion, and preliminary filtering, to ensure the accuracy and reliability of the data;

[0014] A wireless communication sub-module, connected to the data processing unit, is responsible for encoding the preprocessed data and the instructions from the control center, and sending them to the ground control station wirelessly. At the same time, it receives the control instructions and parameter adjustment information from the ground control station;

[0015] A control instruction decoding unit, connected to the wireless communication sub-module, is used to decode the received control instructions and convert them into operation signals executable by the dropping component, including starting / stopping the electric telescopic rod, activating / closing the electromagnetic block;

[0016] A status feedback unit is used to monitor the working status of the signal transmission module itself, including communication link quality, battery power, data transmission rate, and feedback these status information to the ground control station through the wireless communication sub-module.

[0017] An operation method for a UAV fixed-point dropping device includes the following steps:

[0018] S1: The ground control station inputs the accurate position information of the dropping target;

[0019] S2: The UAV obtains the current attitude data through the integrated sensor. The ground control station calculates the pre-dropping attitude that the UAV needs to adjust according to the target information and the current attitude data;

[0020] S3: The UAV adjusts the pitch angle, roll angle, and yaw angle of the UAV through the backstepping control method according to the calculated adjustment amount until it reaches the predetermined attitude. The UAV maintains the predetermined attitude for a period of time and verifies the stability through sensor data to ensure that the UAV is in a stable state before dropping;

[0021] S4: The UAV flies towards the dropping point according to the preset route and real-time navigation information, and monitors the distance between the UAV and the dropping point through GPS in real time. When the UAV approaches the dropping point, it gradually decelerates and hovers at the predetermined height, preparing for dropping;

[0022] S5: Make preparations for dropping, confirm that the dropping object has been correctly loaded into the dropping device, the electric telescopic rod and the electromagnetic block are in a standby state, and according to the accurate position of the dropping point, realize the dropping of the dropping object by controlling the telescopic of the electric telescopic rod and the opening and closing of the electromagnetic block;

[0023] S6: During and after the delivery process, the drone continues to monitor its own attitude changes in real time through the attitude sensor. The control system receives the sensor data and analyzes whether there is an attitude deviation. If an attitude deviation is found, the attitude feedback and adjustment mechanism is immediately activated, and the backstepping control method is used to quickly adjust the attitude of the drone to ensure stable flight;

[0024] S7: According to the requirements of the delivery task, the drone makes the next delivery or returns to the take-off point;

[0025] S8: The ground control station records and analyzes the data of the entire delivery process, including the attitude adjustment effect and the delivery accuracy; According to the mission plan, it controls the drone to return to the take-off point or the designated recovery area;

[0026] S9: Shut down the systems of the drone, disconnect the connection with the ground control station, and complete the current delivery task.

[0027] Preferably, in step S2, the drone obtains the current attitude data through the integrated sensor, and the ground control station calculates the pre-delivery attitude that the drone needs to adjust to according to the target information and the current attitude data; The specific steps are as follows:

[0028] S201: The integrated sensor on the drone measures and transmits the current attitude data to the ground control station in real time, including the roll angle, pitch angle, yaw angle, and linear acceleration and angular velocity information;

[0029] S202: The ground control station receives and stores these data, and at the same time obtains the position information of the delivery target, including longitude, latitude, altitude, and the delivery direction and angle;

[0030] S203: The ground control station converts the geographical coordinate system to the drone body coordinate system to convert the position information of the delivery target into the relative position and direction vector in the drone coordinate system;

[0031] S204: Calculate the relative distance and azimuth from the drone to the delivery target according to the current position of the drone provided by the GPS.

[0032] Preferably, in steps S203 - S204, the ground control station converts the geographical coordinate system to the drone body coordinate system to convert the position information of the delivery target into the relative position and direction vector in the drone coordinate system, and calculates the relative distance and azimuth from the drone to the delivery target according to the current position of the drone provided by the GPS; The specific steps are as follows:

[0033] S2031: Position information conversion: Convert the geographical coordinates (longitude, latitude, altitude) of the delivery target into coordinates (X, Y, Z) in a rectangular coordinate system with the center of the earth as the origin;

[0034] S2032: Rotation Matrix Calculation: Calculate the rotation matrix from the geographic coordinate system to the UAV body coordinate system based on the current attitude (roll angle, pitch angle, yaw angle) of the UAV. This matrix is used to describe the attitude of the UAV relative to the geographic coordinate system;

[0035] S2033: Coordinate Transformation: Use the rotation matrix to convert the coordinates of the dropping target in the geographic coordinate system into the relative position and direction vector in the UAV body coordinate system; the specific formula is as follows:

[0036]

[0037] where R is the rotation matrix, (X, Y, Z) are the coordinates of the dropping target in the geographic coordinate system, and (X', Y', Z') are the coordinates in the converted UAV body coordinate system;

[0038] S2041: Calculate the straight-line distance between the current position of the UAV and the position of the dropping target using the distance formula in three-dimensional space; the calculation formula is as follows:

[0039]

[0040] where (X d , Y d , Z d ) are the coordinates of the UAV in the geographic coordinate system, (X t , Y t , Z t ) are the coordinates of the dropping target in the geographic coordinate system, and d is the straight-line distance between the two;

[0041] S2042: Calculate the azimuth angle between the current position of the UAV and the position of the dropping target using the arctangent function, that is, the angle by which the UAV needs to turn to align with the target; the formula is expressed as follows:

[0042]

[0043] where θ is the azimuth angle, (X d , Y d ) are the coordinates of the UAV in the geographic coordinate system, (X t , Y t ) are the coordinates of the dropping target in the geographic coordinate system;

[0044] S2043: Calculate the required pitch angle adjustment amount based on the height difference (Z t - Z d ) between the dropping target and the horizontal distance d xy between the UAV and the target; the calculation formula is as follows:

[0045]

[0046] Among them, Δφ is the pitch angle adjustment amount, and φcurrent is the current pitch angle of the UAV;

[0047] S2044: Calculate the required roll angle adjustment amount; the calculation formula is as follows:

[0048] Δψ = ψ target - ψ current ;

[0049] Among them, Δψ is the roll angle adjustment amount, ψ target is the target roll angle, and ψ current is the current roll angle of the UAV;

[0050] S2045: According to the azimuth angle θ of the dropping target and the current yaw angle \yaw of the UAV current , calculate the yaw angle adjustment amount that the UAV needs to turn, and the calculation formula is as follows:

[0051] Δ\yaw = θ - \yaw current ;

[0052] Among them, Δ\yaw is the yaw angle adjustment amount.

[0053] Preferably, in step S3, the UAV adjusts the pitch angle, roll angle and yaw angle of the UAV according to the calculated adjustment amount through the backstepping control method until the predetermined attitude is reached; the UAV maintains the predetermined attitude for a period of time, and verifies the stability through sensor data to ensure that the UAV is in a stable state before dropping; the specific steps are as follows:

[0054] S301: Input the target values of the pitch angle, roll angle, and yaw angle of the predetermined attitude (denoted as θ target , φ target , ψ target ), and the actual values of the pitch angle, roll angle, and yaw angle of the current attitude (denoted as θ current , φ current , ψ current );

[0055] S302: Set the control period T and the attitude adjustment threshold ε. The attitude adjustment threshold is used to judge whether the predetermined attitude is reached, and the stability verification time T stable ;

[0056] S303: Calculate the attitude error, including:

[0057] Calculate the pitch angle error, and the calculation formula is: e θ = θ target - θ current ;

[0058] Calculate the roll angle error, and the calculation formula is: eφ = φ target - φ current ;

[0059] Calculate the yaw angle error, and the calculation formula is: e ψ = ψ target - ψ current；

[0060] S304: The control law u can be designed using the PID control algorithm θ such that the pitch angle error e θ approaches 0; The calculation formula is as follows:

[0061] u θ = Kp θ * e θ + Ki θ * ∫e θ dt + Kd θ * de θ / dt;

[0062] S305: Using the PID control algorithm, design the control law u φ such that the roll angle error e φ approaches 0, using the PID control algorithm, design the control law u ψ such that the yaw angle error e ψ approaches 0;

[0063] S306: Convert the control laws u θ , u φ , u ψ into the control signals of the UAV actuator and send them to the UAV. The UAV adjusts its pitch angle, roll angle, and yaw angle according to the received control signals;

[0064] S307: In each control cycle T, obtain the current attitude data of the UAV through the integrated sensor module and update θ current , φ current , ψ current ;

[0065] S308: Determine whether the predetermined attitude is reached. If |e θ | < ε, |e φ | < ε, |e ψ | < ε, it is considered that the UAV has reached the predetermined attitude; otherwise, return to step S304 to continue the adjustment;

[0066] S309: When the UAV reaches the predetermined attitude, maintain this attitude for T stable time; During this period, continuously monitor the attitude data of the UAV to ensure that the attitude error remains within the threshold ε; If within T stableIf the attitude error is always less than ε within a certain time, it is considered that the UAV is in a stable state;

[0067] S310: Output result: The UAV has reached the predetermined attitude and maintains a stable state.

[0068] Preferably, in step S4, the UAV flies towards the dropping point according to the preset flight path and real-time navigation information, and the distance between the UAV and the dropping point is monitored in real time through GPS. When the UAV approaches the dropping point, it gradually decelerates and hovers at a predetermined height, preparing for dropping; the specific steps are as follows:

[0069] S401: The ground control station loads the preset flight path data into the flight control system of the UAV, including longitude and latitude coordinate points, altitude information, and flight speed;

[0070] S402: After the UAV takes off, start the GPS to obtain the current position information of the UAV in real time;

[0071] S403: The UAV calculates the shortest path or the optimal path through the Dijkstra navigation algorithm according to the preset flight path and real-time GPS position information, calculates the flight direction and speed adjustment amount according to the current position and the target point position, calculates the next target point to fly to currently, and adjusts the flight direction of the UAV;

[0072] S404: During the flight, continuously monitor the real-time distance between the UAV and the dropping point through GPS, specifically including:

[0073] Input: Real-time position data of the UAV, position data of the dropping point;

[0074] Processing: Calculate the straight-line distance between two points and the actual distance according to the longitude and latitude;

[0075] Output: Real-time distance between the UAV and the dropping point;

[0076] S405: When the distance between the UAV and the dropping point is less than the preset threshold, calculate the deceleration rate according to the relationship between the distance and the speed; when reaching the predetermined height, output a deceleration command and a hover command to the UAV to control the UAV to hover;

[0077] S406: The UAV gradually decelerates and prepares to hover at a predetermined height;

[0078] S407: The UAV hovers at the predetermined height, ensures the position stability, prepares for dropping, monitors the position stability of the UAV, and ensures to hover at the predetermined height for a period of time to verify the stability; after the stability verification is completed, output a signal indicating that the dropping preparation is completed.

[0079] Preferably, in step S5, preparation for delivery is carried out. It is confirmed that the delivery item has been correctly loaded into the delivery device, and the electric telescopic rod and the electromagnetic block are in a standby state. According to the precise position of the delivery point, the delivery of the delivery item is achieved by controlling the telescopic movement of the electric telescopic rod and the opening and closing of the electromagnetic block. The specific steps are as follows:

[0080] S501: Confirm the loading status of the delivery item, specifically including:

[0081] Input: The loading situation of the delivery device;

[0082] Processing: Through the sensor data in the delivery device, confirm whether the delivery item has been correctly and firmly loaded on the delivery component;

[0083] Output: The confirmation result of the loading status;

[0084] S502: Check the status of the electric telescopic rod and the electromagnetic block, specifically including:

[0085] Input: The status of the electric telescopic rod, the status of the electromagnetic block;

[0086] Processing: Send a query instruction through the signal transmission module to obtain whether the electric telescopic rod is in the initial position and whether the electromagnetic block is in the unactivated (i.e., closed) state;

[0087] Output: The confirmation result of the status of the electric telescopic rod and the electromagnetic block;

[0088] S503: Calculate the precise position of the delivery point, specifically including:

[0089] Input: GPS data, preset delivery point coordinates;

[0090] Processing: Combine the current GPS position information of the drone and the preset delivery point coordinates, and calculate the precise relative position of the drone relative to the delivery point through the geographic coordinate conversion algorithm;

[0091] Output: The precise relative position data of the delivery point;

[0092] S504: Develop a delivery strategy, specifically including:

[0093] Input: The precise position of the delivery point, the current attitude of the drone;

[0094] Processing: According to the position information of the delivery point, the current attitude of the drone (pitch angle, roll angle, yaw angle) and the characteristics of the delivery item (weight, shape), develop a delivery strategy, including the telescopic length of the electric telescopic rod and the opening and closing timing of the electromagnetic block.

[0095] Output: Delivery strategy parameters, including the telescopic amount of the electric telescopic rod and the opening and closing time of the electromagnetic block;

[0096] S505: Execute the dropping action, specifically including:

[0097] Input: Dropping strategy parameters;

[0098] Process: Send a control instruction to the electric telescopic rod to make it expand and contract according to the calculated amount of expansion and contraction, and move the dropped object to the dropping position; when the dropped object reaches the predetermined dropping position, send an activation instruction to the electromagnetic block to make it instantly lose magnetism and release the dropped object;

[0099] Output: The execution result of the dropping action and the status data during the dropping process (the expansion and contraction situation of the electric telescopic rod, the opening and closing state of the electromagnetic block).

[0100] Preferably, in step S6, during and after the dropping process, the drone continues to monitor its own attitude changes in real time through the attitude sensor. The control system receives the sensor data and analyzes whether there is an attitude deviation. If an attitude deviation is found, the attitude feedback and adjustment mechanism is immediately activated, and the attitude of the drone is quickly adjusted through the backstepping control method to ensure stable flight; the specific steps are as follows:

[0101] S601: Monitor attitude data in real time, specifically including:

[0102] Input: The roll angle, pitch angle, and yaw angle data measured in real time by the attitude sensor;

[0103] Process: The control system receives data from the attitude sensor at a fixed frequency;

[0104] Output: The updated roll angle, pitch angle, and yaw angle values in real time;

[0105] S602: Attitude deviation detection, specifically including:

[0106] Input: The attitude data measured in real time and the preset stable attitude threshold;

[0107] Process: Compare the attitude data measured in real time with the preset stable attitude range to determine whether there is a deviation;

[0108] Output: The attitude deviation detection result, including the magnitude and direction of the deviation;

[0109] S603: Deviation threshold judgment, specifically including:

[0110] Input: The attitude deviation detection result;

[0111] Process: Set a deviation threshold. If the attitude deviation exceeds this threshold, the adjustment mechanism is triggered;

[0112] Output: A decision signal on whether to adjust the attitude of the drone.;

[0113] S604: Activate the attitude feedback and adjustment mechanism, specifically including:

[0114] Input: The decision signal for adjusting the UAV attitude;

[0115] Process: When the decision signal is "Yes", activate the attitude feedback and adjustment mechanism and prepare for attitude adjustment;

[0116] Output: The signal for activating the adjustment mechanism and the initial adjustment parameters;

[0117] S605: Calculate the attitude adjustment amount, specifically including:

[0118] Input: The attitude data measured in real time and the predetermined attitude target value;

[0119] Process: Use the PID control algorithm and the backstepping control algorithm in step S3 to calculate the adjustment amount required to reach the predetermined attitude, including the adjustment amounts of the roll angle, pitch angle, and yaw angle;

[0120] Output: The attitude adjustment amount, including the roll angle adjustment amount, pitch angle adjustment amount, and yaw angle adjustment amount;

[0121] S606: Execute attitude adjustment, specifically including:

[0122] Input: The attitude adjustment amount;

[0123] Process: Convert the calculated attitude adjustment amount into a control signal for the UAV actuator, such as a motor speed adjustment signal or a servo control signal;

[0124] Output: The actuator control signal to drive the UAV for attitude adjustment;

[0125] S607: Monitor the adjustment effect, specifically including:

[0126] Input: The attitude sensor data after the execution of the actuator control signal;

[0127] Process: Monitor the attitude data of the UAV again and evaluate the adjustment effect;

[0128] Output: The adjusted attitude data and the effect evaluation result;

[0129] S608: Perform cyclic adjustment until stable, specifically including:

[0130] Input: The adjusted attitude data and the effect evaluation result;

[0131] Process: If the attitude has not reached the stable state yet, repeat the steps from S602 to S607 until the UAV attitude is stable within the preset range;

[0132] Output: The state signal of the UAV flying stably;

[0133] S609: Record and feedback the adjustment process, specifically including:

[0134] Input: Attitude data, adjustment amount, and actuator control signals during the entire adjustment process;

[0135] Processing: Record and store these data;

[0136] Output: Record data of the adjustment process for analysis by the ground control station and R & D personnel.

[0137] Advantages of the present invention:

[0138] 1. Compared with the problem of insufficient attitude pre - adjustment of the existing UAV fixed - point delivery device, the present invention precisely pre - adjusts the attitude of the UAV through the ground control station to ensure that the UAV is in the best stable state before delivery; through automated algorithms and control instructions, the pitch angle, roll angle, and yaw angle of the UAV are adjusted so that the UAV can accurately point to the delivery target, improving the delivery accuracy and the stability of the UAV.

[0139] 2. Compared with the problem of inaccurate delivery control of the existing UAV fixed - point delivery device, the present invention uses an algorithm to dynamically adjust the opening and closing timing and force of the electric telescopic rod and the electromagnetic block according to the real - time position and attitude data of the UAV. Through precise control instructions and a real - time feedback mechanism, it ensures that the delivery object can accurately reach the predetermined position, improving the accuracy and reliability of the delivery.

[0140] 3. Compared with the problem of imperfect attitude feedback and adjustment mechanism of the existing UAV fixed - point delivery device, it integrates multiple sensor data to achieve multi - sensor fusion and real - time data analysis, improving the accuracy and reliability of attitude monitoring. The backstepping control algorithm is used to control the attitude angle and angular velocity of the UAV to ensure the stability of the UAV during delivery. When the UAV has an attitude deviation, the control system can activate the attitude feedback and adjustment mechanism to quickly correct the deviation, ensuring that the UAV can fly stably and complete the subsequent delivery task. Brief Description of the Drawings

[0141] Figure 1 Shown is the first three - dimensional structure schematic diagram of the UAV fixed - point delivery device of the present invention;

[0142] Figure 2 Shown is the second three - dimensional structure schematic diagram of the UAV fixed - point delivery device of the present invention;

[0143] Figure 3 Shown is the schematic diagram of the operation method steps flow of the UAV fixed - point delivery device of the present invention;

[0144] Description of reference numerals: 1, unmanned aerial vehicle (UAV) frame; 2, integrated sensor module; 3, signal transmission module; 4, bracket; 501, electric telescopic rod; 502, electromagnetic block; 503, metal connection block; 504, hanging ring. Detailed implementation manners

[0145] The present invention will be further described below with reference to the accompanying drawings and embodiments.

[0146] Please refer to Figures 1-3 , the present invention provides an embodiment: a UAV fixed-point delivery device, including a UAV frame 1, an integrated sensor module 2, a signal transmission module 3, a bracket 4 and a delivery component; an integrated sensor module 2 is arranged above the UAV frame 1, a signal transmission module 3 is arranged above the UAV frame 1, a bracket 4 is arranged below the UAV frame 1, and a delivery component is arranged below the UAV frame 1; the delivery component includes an electric telescopic rod 501, an electromagnetic block 502, a metal connection block 503 and a hanging ring 504; an electric telescopic rod 501 is arranged below the UAV frame 1, an electromagnetic block 502 is arranged at one end of the electric telescopic rod 501, a metal connection block 503 is arranged below the electromagnetic block 502, and a hanging ring 504 is arranged below the metal connection block 503.

[0147] Preferably, the integrated sensor module 2 includes a gyroscope, an accelerometer and a magnetometer; the gyroscope is used to measure in real time the angular velocity of the UAV around its three main axes, namely the roll axis, the pitch axis and the yaw axis, so as to provide the attitude angle change information of the UAV; the accelerometer is used to measure the linear acceleration of the UAV in three axial directions, namely front-back, left-right, up-down, as well as the components of the gravitational acceleration in the UAV coordinate system; the magnetometer is used to measure the three components of the geomagnetic field in the UAV coordinate system to determine the heading angle of the UAV, that is, the yaw angle; the data of the magnetometer is combined with the data of the gyroscope and the accelerometer to describe the attitude and heading of the UAV and provide precise navigation information for fixed-point delivery.

[0148] Preferably, the signal transmission module 3 is arranged above the UAV frame 1 and is electrically connected to the integrated sensor module 2 and the delivery component; the signal transmission module 3 includes:

[0149] A data receiving unit, configured to receive real-time data from the integrated sensor module 2, including but not limited to the angular velocity data measured by the gyroscope, the linear acceleration and gravitational acceleration data measured by the accelerometer, and the geomagnetic field data measured by the magnetometer;

[0150] A data processing unit, connected to the data receiving unit, configured to preprocess the received data, including but not limited to data verification, format conversion and preliminary filtering, to ensure the accuracy and reliability of the data;

[0151] A wireless communication sub-module, connected to the data processing unit, responsible for encoding the pre-processed data and instructions from the control center, and transmitting them wirelessly to the ground control station. At the same time, it receives control instructions and parameter adjustment information from the ground control station;

[0152] A control instruction decoding unit, connected to the wireless communication sub-module, used to decode the received control instructions and convert them into operation signals executable by the delivery component, including starting / stopping the electric telescopic rod 501 and activating / closing the electromagnetic block 502;

[0153] A status feedback unit, used to monitor the working status of the signal transmission module 3 itself, including communication link quality, battery power, and data transmission rate, and feedback these status information to the ground control station through the wireless communication sub-module.

[0154] An operation method for a UAV fixed-point delivery device, including the following steps:

[0155] S1: The ground control station inputs the accurate position information of the delivery target;

[0156] S2: The UAV obtains the current attitude data through the integrated sensor. The ground control station calculates the pre-delivery attitude that the UAV needs to adjust according to the target information and the current attitude data;

[0157] S3: The UAV adjusts the pitch angle, roll angle, and yaw angle of the UAV through the backstepping control method according to the calculated adjustment amount until the predetermined attitude is reached; the UAV maintains the predetermined attitude for a period of time, and verifies the stability through sensor data to ensure that the UAV is in a stable state before delivery;

[0158] S4: The UAV flies towards the delivery point according to the preset route and real-time navigation information, and monitors the distance between the UAV and the delivery point in real time through GPS. When the UAV approaches the delivery point, it gradually decelerates and hovers at a predetermined height, preparing for delivery;

[0159] S5: Make delivery preparations, confirm that the delivery object has been correctly loaded into the delivery device, the electric telescopic rod and the electromagnetic block are in a standby state, and realize the delivery of the delivery object by controlling the extension and retraction of the electric telescopic rod and the opening and closing of the electromagnetic block according to the accurate position of the delivery point;

[0160] S6: During and after the delivery process, the UAV continues to monitor its own attitude changes in real time through the attitude sensor. The control system receives the sensor data and analyzes whether there is an attitude deviation. If an attitude deviation is found, it immediately activates the attitude feedback and adjustment mechanism, and quickly adjusts the UAV attitude through the backstepping control method to ensure stable flight;

[0161] S7: According to the delivery task requirements, the UAV makes the next delivery or returns to the take-off point;

[0162] S8: The ground control station records and analyzes the data of the entire dropping process, including the attitude adjustment effect and dropping accuracy; according to the mission plan, controls the UAV to return to the take-off point or the designated recovery area;

[0163] S9: Shuts down each system of the UAV, disconnects the connection with the ground control station, and completes the current dropping mission.

[0164] Preferably, in step S2, the UAV obtains the current attitude data through the integrated sensor, and the ground control station calculates the pre-dropping attitude that the UAV needs to adjust to according to the target information and the current attitude data; the specific steps are as follows:

[0165] S201: The integrated sensor on the UAV measures and transmits the current attitude data to the ground control station in real time, including roll angle, pitch angle, yaw angle, and linear acceleration and angular velocity information;

[0166] S202: The ground control station receives and stores this data, and at the same time obtains the position information of the dropping target, including longitude, latitude, altitude, and dropping direction and angle;

[0167] S203: The ground control station converts the geographical coordinate system to the UAV body coordinate system to convert the position information of the dropping target into the relative position and direction vector in the UAV coordinate system;

[0168] S204: Calculates the relative distance and azimuth from the UAV to the dropping target according to the current position of the UAV provided by the GPS.

[0169] Preferably, in steps S203 - S204, the ground control station converts the geographical coordinate system to the UAV body coordinate system to convert the position information of the dropping target into the relative position and direction vector in the UAV coordinate system, and calculates the relative distance and azimuth from the UAV to the dropping target according to the current position of the UAV provided by the GPS; the specific steps are as follows:

[0170] S2031: Position information conversion: Converts the geographical coordinates (longitude, latitude, altitude) of the dropping target into the coordinates (X, Y, Z) in the rectangular coordinate system with the center of the earth as the origin;

[0171] S2032: Rotation matrix calculation: Calculates the rotation matrix from the geographical coordinate system to the UAV body coordinate system according to the current attitude (roll angle, pitch angle, yaw angle) of the UAV, and this matrix is used to describe the attitude of the UAV relative to the geographical coordinate system;

[0172] S2033: Coordinate transformation: Uses the rotation matrix to convert the coordinates of the dropping target in the geographical coordinate system into the relative position and direction vector in the UAV body coordinate system; the specific formula is as follows:

[0173]

[0174] Among them, R is the rotation matrix, (X, Y, Z) are the coordinates of the dropping target in the geographic coordinate system, and (X', Y', Z') are the coordinates in the converted UAV body coordinate system;

[0175] S2041: Calculate the straight-line distance between the current position of the UAV and the dropping target position using the distance formula in three-dimensional space; the calculation formula is as follows:

[0176]

[0177] Among them, (X d , Y d , Z d ) are the coordinates of the UAV in the geographic coordinate system, (X t , Y t , Z t ) are the coordinates of the dropping target in the geographic coordinate system, and d is the straight-line distance between the two;

[0178] S2042: Calculate the azimuth angle between the current position of the UAV and the dropping target position using the arctangent function, that is, the angle by which the UAV needs to turn to align with the target; the formula is expressed as follows:

[0179]

[0180] Among them, θ is the azimuth angle, (X d , Y d ) are the coordinates of the UAV in the geographic coordinate system, (X t , Y t ) are the coordinates of the dropping target in the geographic coordinate system;

[0181] S2043: Calculate the required pitch angle adjustment amount according to the height difference (Z t - Z d ) of the dropping target and the horizontal distance d xy between the UAV and the target; the calculation formula is as follows:

[0182]

[0183] Among them, Δφ is the pitch angle adjustment amount, and φcurrent is the current pitch angle of the UAV;

[0184] S2044: Calculate the required roll angle adjustment amount; the calculation formula is as follows:

[0185] Δψ = ψ target - ψ current ;

[0186] Among them, Δψ is the roll angle adjustment amount, and ψ target is the target roll angle, and ψ current is the current roll angle of the UAV;

[0187] S2045: According to the azimuth angle θ of the dropping target and the current yaw angle \yaw current of the UAV, calculate the yaw angle adjustment amount that the UAV needs to turn, and the calculation formula is as follows:

[0188] Δ\yaw = θ - \yaw current ;

[0189] Among them, Δ\yaw is the yaw angle adjustment amount.

[0190] Preferably, in step S3, the UAV adjusts the pitch angle, roll angle and yaw angle of the UAV according to the calculated adjustment amount until the predetermined attitude is reached; the UAV maintains the predetermined attitude for a period of time, and verifies the stability through sensor data to ensure that the UAV is in a stable state before dropping; the specific steps are as follows:

[0191] S301: Input the target values of the pitch angle, roll angle, and yaw angle of the predetermined attitude (denoted as θ target , φ target , ψ target ), and the actual values of the pitch angle, roll angle, and yaw angle of the current attitude (denoted as θ current , φ current , ψ current );

[0192] S302: Set the control period T and the attitude adjustment threshold ε. The attitude adjustment threshold is used to judge whether the predetermined attitude is reached, and the stability verification time T stable ;

[0193] S303: Calculate the attitude error, including:

[0194] Calculate the pitch angle error, and the calculation formula is: e θ = θ target - θ current ;

[0195] Calculate the roll angle error, and the calculation formula is: e φ = φ target - φ current ;

[0196] Calculate the yaw angle error, and the calculation formula is: e ψ = ψ target - ψ current；

[0197] S304: The control law u can be designed by using the PID control algorithm θ, such that the pitch angle error e θ approaches 0; the calculation formula is as follows:

[0198] u θ = Kp θ *e θ + Ki θ *∫e θ dt + Kd θ *de θ / dt;

[0199] S305: Adopt the PID control algorithm to design the control law u φ , such that the roll angle error e φ approaches 0. Adopt the PID control algorithm to design the control law u ψ , such that the yaw angle error e ψ approaches 0;

[0200] S306: Convert the control laws u θ , u φ , u ψ into the control signals of the UAV actuators and send them to the UAV. The UAV adjusts its pitch angle, roll angle and yaw angle according to the received control signals;

[0201] S307: Within each control period T, obtain the current attitude data of the UAV through the integrated sensor module and update θ current , φ current , ψ current ;

[0202] S308: Judge whether the predetermined attitude is reached. If |e θ | < ε, |e φ | < ε, |e ψ | < ε, it is considered that the UAV has reached the predetermined attitude; otherwise, return to step S304 to continue adjustment;

[0203] S309: When the UAV reaches the predetermined attitude, maintain this attitude for T stable time; during this period, continuously monitor the attitude data of the UAV to ensure that the attitude error remains within the threshold ε; if within T stable time, the attitude error is always less than ε, it is considered that the UAV is in a stable state;

[0204] S310: Output the result: The UAV has reached the predetermined attitude and maintains a stable state.

[0205] Preferably, in step S4, the drone flies towards the dropping point according to the preset flight path and real-time navigation information, and the distance between the drone and the dropping point is monitored in real time through GPS. When the drone approaches the dropping point, it gradually decelerates and hovers at a predetermined height, preparing for dropping. The specific steps are as follows:

[0206] S401: The ground control station loads the preset flight path data into the flight control system of the drone, including latitude and longitude coordinate points, altitude information, and flight speed;

[0207] S402: After the drone takes off, it starts the GPS to obtain the current position information of the drone in real time;

[0208] S403: The drone calculates the shortest path or the optimal path through the Dijkstra navigation algorithm according to the preset flight path and the real-time GPS position information, calculates the flight direction and speed adjustment amount based on the current position and the target point position, calculates the next target point to fly to currently, and adjusts the flight direction of the drone;

[0209] S404: During the flight, continuously monitor the real-time distance between the drone and the dropping point through GPS, specifically including:

[0210] Input: The real-time position data of the drone and the position data of the dropping point;

[0211] Process: Calculate the straight-line distance between the two points and the actual distance according to the latitude and longitude;

[0212] Output: The real-time distance between the drone and the dropping point;

[0213] S405: When the distance between the drone and the dropping point is less than the preset threshold, calculate the deceleration rate according to the relationship between the distance and the speed; when reaching the predetermined height, output a deceleration instruction and a hovering instruction to the drone to control the drone to hover;

[0214] S406: The drone gradually decelerates and prepares to hover at a predetermined height;

[0215] S407: The drone hovers at the predetermined height, ensures the position stability, prepares for dropping, monitors the position stability of the drone, and ensures to hover at the predetermined height for a period of time to verify the stability; after the stability verification is completed, output a signal indicating that the dropping preparation is completed.

[0216] Preferably, in step S5, for the dropping preparation, confirm that the dropped object has been correctly loaded into the dropping device, the electric telescopic rod and the electromagnetic block are in the standby state, and according to the accurate position of the dropping point, control the telescopic of the electric telescopic rod and the opening and closing of the electromagnetic block to realize the dropping of the dropped object. The specific steps are as follows:

[0217] S501: Confirm the loading status of the dropped object, specifically including:

[0218] Input: Loading status of the dispensing device;

[0219] Process: Through the sensor data in the dispensing device, confirm whether the dispensed object is correctly and firmly loaded on the dispensing component;

[0220] Output: Loading status confirmation result;

[0221] S502: Check the status of the electric telescopic rod and the electromagnetic block, specifically including:

[0222] Input: Status of the electric telescopic rod, status of the electromagnetic block;

[0223] Process: Send a query instruction through the signal transmission module to obtain whether the electric telescopic rod is in the initial position and whether the electromagnetic block is in the unactivated (i.e., off) state;

[0224] Output: Status confirmation result of the electric telescopic rod and the electromagnetic block;

[0225] S503: Calculate the precise position of the dispensing point, specifically including:

[0226] Input: GPS data, preset dispensing point coordinates;

[0227] Process: Combine the current GPS position information of the drone and the preset dispensing point coordinates, and calculate the precise relative position of the drone relative to the dispensing point through the geographic coordinate conversion algorithm;

[0228] Output: Precise relative position data of the dispensing point;

[0229] S504: Develop a dispensing strategy, specifically including:

[0230] Input: Precise position of the dispensing point, current attitude of the drone;

[0231] Process: According to the position information of the dispensing point, the current attitude of the drone (pitch angle, roll angle, yaw angle) and the characteristics of the dispensed object (weight, shape), develop a dispensing strategy, including the telescopic length of the electric telescopic rod and the opening and closing timing of the electromagnetic block.

[0232] Output: Dispensing strategy parameters, including the telescopic amount of the electric telescopic rod and the opening and closing time of the electromagnetic block;

[0233] S505: Execute the dispensing action, specifically including:

[0234] Input: Dispensing strategy parameters;

[0235] Process: Send a control instruction to the electric telescopic rod to make it expand and contract according to the calculated amount of expansion and contraction, and move the dropped object to the dropping position; when the dropped object reaches the predetermined dropping position, send an activation instruction to the electromagnetic block to make it instantly lose magnetism and release the dropped object;

[0236] Output: The execution result of the dropping action and the status data during the dropping process (the expansion and contraction situation of the electric telescopic rod, the opening and closing state of the electromagnetic block).

[0237] Preferably, in step S6, during and after the dropping process, the drone continues to monitor its own attitude changes in real time through the attitude sensor. The control system receives the sensor data and analyzes whether there is an attitude deviation. If an attitude deviation is found, the attitude feedback and adjustment mechanism is immediately started, and the attitude of the drone is quickly adjusted through the backstepping control method to ensure stable flight; the specific steps are as follows:

[0238] S601: Monitor the attitude data in real time, specifically including:

[0239] Input: The roll angle, pitch angle, and yaw angle data measured by the attitude sensor in real time;

[0240] Process: The control system receives data from the attitude sensor at a fixed frequency;

[0241] Output: The updated roll angle, pitch angle, and yaw angle values in real time;

[0242] S602: Detect the attitude deviation, specifically including:

[0243] Input: The attitude data measured in real time and the preset stable attitude threshold;

[0244] Process: Compare the attitude data measured in real time with the preset stable attitude range to judge whether there is a deviation;

[0245] Output: The attitude deviation detection result, including the deviation magnitude and direction;

[0246] S603: Judge the deviation threshold, specifically including:

[0247] Input: The attitude deviation detection result;

[0248] Process: Set a deviation threshold. If the attitude deviation exceeds this threshold, the adjustment mechanism is triggered;

[0249] Output: A decision signal on whether to adjust the attitude of the drone.;

[0250] S604: Start the attitude feedback and adjustment mechanism, specifically including:

[0251] Input: The decision signal to adjust the attitude of the drone;

[0252] Processing: When the decision signal is "Yes", activate the attitude feedback and adjustment mechanism and prepare for attitude adjustment;

[0253] Output: The signal to activate the adjustment mechanism and the initial adjustment parameters;

[0254] S605: Calculate the attitude adjustment amount, specifically including:

[0255] Input: The attitude data measured in real time and the predetermined attitude target value;

[0256] Processing: Use the PID control algorithm and the backstepping control algorithm in step S3 to calculate the adjustment amount required to reach the predetermined attitude, including the adjustment amounts of the roll angle, pitch angle, and yaw angle;

[0257] Output: The attitude adjustment amount, including the roll angle adjustment amount, pitch angle adjustment amount, and yaw angle adjustment amount;

[0258] S606: Perform attitude adjustment, specifically including:

[0259] Input: The attitude adjustment amount;

[0260] Processing: Convert the calculated attitude adjustment amount into a control signal for the UAV actuator, such as a motor speed adjustment signal or a servo control signal;

[0261] Output: The actuator control signal to drive the UAV to perform attitude adjustment;

[0262] S607: Monitor the adjustment effect, specifically including:

[0263] Input: The attitude sensor data after the execution of the actuator control signal;

[0264] Processing: Monitor the attitude data of the UAV again and evaluate the adjustment effect;

[0265] Output: The adjusted attitude data and the effect evaluation result;

[0266] S608: Loop adjustment until stable, specifically including:

[0267] Input: The adjusted attitude data and the effect evaluation result;

[0268] Processing: If the attitude has not reached the stable state, repeat the steps of S602 to S607 until the UAV attitude is stable within the preset range;

[0269] Output: The state signal of the UAV flying stably;

[0270] S609: Record and feedback the adjustment process, specifically including:

[0271] Input: Attitude data, adjustment amount, and actuator control signal during the entire adjustment process;

[0272] Process: Record and store these data;

[0273] Output: Record data of the adjustment process for analysis by the ground control station and R & D personnel.

[0274] Embodiment

[0275] Optionally, it is set that during an agricultural seeding task, a drone is required to precisely drop seeds into a designated farmland area; the coordinates of the farmland are (longitude, latitude), the height of the dropping point is 50 meters, the takeoff point of the drone is (longitude, latitude), and the height is 10 meters; it is required that the dropping accuracy of the drone is within ±0.5 meters, and the drone needs to maintain stable flight during the dropping process;

[0276] Among them, drone parameters:

[0277] Drone frame size: 1.5 meters (wingspan);

[0278] Stroke of the electric telescopic rod: 0.5 meters;

[0279] Adsorption force of the electromagnetic block: 50N;

[0280] Accuracy of the integrated sensor module: gyroscope ±0.01° / s, accelerometer ±0.02g, magnetometer ±0.5°;

[0281] Dropping point information:

[0282] Coordinates of the dropping point: (longitude, latitude), height 50 meters;

[0283] Dropping target direction: 45° angle with the takeoff point direction;

[0284] Attitude pre-adjustment data:

[0285] Initial pitch angle: 10°;

[0286] Initial roll angle: 0°;

[0287] Initial yaw angle: 0°;

[0288] Target pitch angle: 30°;

[0289] Target roll angle: 0°;

[0290] Target yaw angle: 45°;

[0291] Dropping control data:

[0292] Stroke of the electric telescopic rod: 0.3 meters;

[0293] Electromagnetic block opening and closing timing: When the dropped object reaches the predetermined dropping position, that is, 0.1 second after the electric telescopic rod is fully extended;

[0294] Attitude feedback and adjustment data:

[0295] Attitude deviation threshold: Pitch angle ±2°, roll angle ±1°, yaw angle ±3°;

[0296] PID control parameters: Kpθ = 0.5, Kiθ = 0.1, Kdθ = 0.05;

[0297] The ground control station calculates the pre-dropping attitude that the UAV needs to adjust according to the target information and the current attitude data; the UAV adjusts the pitch angle, roll angle and yaw angle according to the calculated adjustment amount through the backstepping control method; the data comparison is as follows:

[0298] Before adjustment: Pitch angle 10°, roll angle 0°, yaw angle 0°;

[0299] After adjustment: Pitch angle 30°, roll angle 0°, yaw angle 45°;

[0300] The UAV is successfully adjusted to the predetermined attitude and is ready for dropping;

[0301] The UAV flies towards the dropping point according to the preset route and real-time navigation information. When the UAV approaches the dropping point, it gradually decelerates and hovers at the predetermined height; according to the precise position of the dropping point, the dropping of the dropped object is realized by controlling the telescopic movement of the electric telescopic rod and the opening and closing of the electromagnetic block; the data comparison is as follows:

[0302] Distance before dropping: 20 meters (calculated according to GPS data);

[0303] Telescopic amount of the electric telescopic rod during dropping: 0.3 meters;

[0304] Electromagnetic block opening and closing timing: 0.1 second after the electric telescopic rod is fully extended;

[0305] Dropping accuracy: ±0.2 meters (obtained by actual measurement);

[0306] The dropped object accurately reaches the predetermined position, and the dropping accuracy is higher than the required ±0.5 meters;

[0307] During and after the dropping process, the UAV continues to monitor its own attitude changes in real time through the attitude sensor. When an attitude deviation is detected, the attitude feedback and adjustment mechanism is immediately activated, and the UAV attitude is quickly adjusted through the backstepping control method; the data comparison is as follows:

[0308] Maximum attitude deviation during dropping process: Pitch angle ±1°, roll angle ±0.5°, yaw angle ±1.5°;

[0309] Adjustment time: 0.5 s (from deviation detection to adjustment completion);

[0310] Post - adjustment attitude stability: pitch angle ±0.5°, roll angle ±0.2°, yaw angle ±1°;

[0311] The UAV maintained good stability during the delivery process, and the attitude deviation was corrected in a timely and effective manner;

[0312] Among them, the data of each step are compared as shown in the following figure:

[0313]

[0314]

[0315] In summary, through example data and numerical comparison, the technical solution of the present invention draws the following conclusions:

[0316] 1. Improvement in the accuracy of attitude pre - adjustment: The UAV was successfully adjusted from the initial attitude to the predetermined delivery attitude, laying a solid foundation for the high precision and stability of the delivery process;

[0317] 2. Improvement in the accuracy of delivery control: Through precise control of the electric telescopic rod and accurate timing of the opening and closing of the electromagnetic block, the delivery object reached the predetermined position accurately, and the delivery accuracy far exceeded the required standard;

[0318] 3. Improvement in the attitude feedback and adjustment mechanism: During and after the delivery process, the UAV real - time monitors and quickly adjusts its attitude through an attitude sensor, ensuring the stability of the UAV and the smooth progress of subsequent tasks;

[0319] Thus, it fully verifies its remarkable effect in improving the accuracy, stability and reliability of the UAV fixed - point delivery device.

[0320] The above has described the embodiments of the present invention in detail with reference to the accompanying drawings. However, the present invention is not limited to the above - described embodiments. Within the scope of knowledge possessed by those skilled in the art, various changes can be made without departing from the gist of the present invention.

Claims

1. An operation method of a fixed-point delivery device for an unmanned aerial vehicle, characterized in that: It includes the following steps: S1: The ground control station inputs the accurate position information of the dropping target; S2: The drone obtains the current attitude data through the integrated sensors. The ground control station calculates the pre-dropping attitude that the drone needs to adjust to based on the target information and the current attitude data; S3: The drone adjusts the pitch angle, roll angle, and yaw angle of the drone through the backstepping control method according to the calculated adjustment amount until it reaches the predetermined attitude. The drone maintains the predetermined attitude for a period of time and verifies the stability through the sensor data to ensure that the drone is in a stable state before dropping; S4: The drone flies towards the dropping point according to the preset route and real-time navigation information, and monitors the distance between the drone and the dropping point in real time through GPS. When the drone approaches the dropping point, it gradually decelerates and hovers at the predetermined height, preparing for dropping; S5: Make preparations for dropping, confirm that the dropped object has been correctly loaded into the dropping device, and the electric telescopic rod and the electromagnetic block are in a standby state. According to the accurate position of the dropping point, the dropping of the dropped object is realized by controlling the telescopic movement of the electric telescopic rod and the opening and closing of the electromagnetic block; S6: During and after the dropping process, the drone continues to monitor its own attitude changes in real time through the attitude sensor. The control system receives the sensor data and analyzes whether there is an attitude deviation. If an attitude deviation is found, the attitude feedback and adjustment mechanism is immediately started, and the attitude of the drone is quickly adjusted through the backstepping control method to ensure stable flight; S7: According to the requirements of the dropping task, the drone conducts the next dropping or returns to the takeoff point; S8: The ground control station records and analyzes the data of the entire dropping process, including the attitude adjustment effect and the dropping accuracy; according to the task plan, it controls the drone to return to the takeoff point or the designated recovery area; S9: Shut down the systems of the drone, disconnect the connection with the ground control station, and complete the current dropping task; In step S2, the drone obtains the current attitude data through the integrated sensors. The ground control station calculates the pre-dropping attitude that the drone needs to adjust to based on the target information and the current attitude data; The specific steps are as follows: S201: The integrated sensors on the drone measure and transmit the current attitude data to the ground control station in real time, including the roll angle, pitch angle, yaw angle, and linear acceleration and angular velocity information; S202: The ground control station receives and stores these data, and at the same time obtains the position information of the dropping target, including longitude, latitude, altitude, and dropping direction and angle; S203: The ground control station converts the geographic coordinate system to the drone body coordinate system to convert the position information of the dropping target into the relative position and direction vector in the drone coordinate system; S204: Calculate the relative distance and azimuth from the drone to the dropping target according to the current position of the drone provided by GPS; In steps S203 - S204, the ground control station converts the geographic coordinate system to the drone body coordinate system to convert the position information of the dropping target into the relative position and direction vector in the drone coordinate system, and calculates the relative distance and azimuth from the drone to the dropping target according to the current position of the drone provided by GPS. The specific steps are as follows: S2031: Location information conversion: Convert the geographical coordinates (longitude, latitude, altitude) of the dropping target into coordinates (X, Y, Z) in a rectangular coordinate system with the center of the earth as the origin; S2032: Rotation matrix calculation: Calculate the rotation matrix from the geographical coordinate system to the UAV body coordinate system according to the current attitude (roll angle, pitch angle, yaw angle) of the UAV. This matrix is used to describe the attitude of the UAV relative to the geographical coordinate system; S2033: Coordinate transformation: Use the rotation matrix to convert the coordinates of the dropping target in the geographical coordinate system into the relative position and direction vector in the UAV body coordinate system; The specific formula is as follows: where R is the rotation matrix, (X, Y, Z) are the coordinates of the dropping target in the geographical coordinate system, and (X', Y', Z') are the coordinates in the converted UAV body coordinate system; S2041: Calculate the straight-line distance between the current position of the UAV and the position of the dropping target using the distance formula in three-dimensional space; The calculation formula is as follows: Among them, (X d , Y d , Z d ) are the coordinates of the drone in the geographic coordinate system, (X t , Y t , Z t ) are the coordinates of the delivery target in the geographic coordinate system, and d is the straight-line distance between the two; S2042: Calculate the azimuth angle between the current position of the UAV and the position of the dropping target using the arctangent function, that is, the angle by which the UAV needs to turn to align with the target; The formula is expressed as follows: where θ is the azimuth angle, (X d , Y d ) are the coordinates of the UAV in the geographic coordinate system, and (X t , Y t ) are the coordinates of the dropping target in the geographic coordinate system; S2043: According to the height difference (Z t -Z d ) between the delivery target and the horizontal distance d between the drone and the target xy , calculate the required pitch angle adjustment amount; the calculation formula is as follows: where Δφ is the pitch angle adjustment amount, and φcurrent is the current pitch angle of the UAV; S2044: Calculate the required roll angle adjustment amount; The calculation formula is as follows: Δψ = ψ target -ψ current ; where Δψ is the roll angle adjustment amount, ψ target is the target roll angle, and ψ current is the current roll angle of the UAV; S2045: Calculate the yaw angle adjustment amount that the UAV needs to turn according to the azimuth angle θ of the delivery target and the current yaw angle \yaw of the UAV current , and the calculation formula is as follows: Δ\yaw = θ - \yaw current ; where Δyaw is the yaw angle adjustment amount; In step S3, the UAV adjusts the pitch angle, roll angle, and yaw angle of the UAV through the backstepping control method according to the calculated adjustment amounts until the predetermined attitude is reached; The UAV maintains the predetermined attitude for a period of time and verifies the stability through sensor data to ensure that the UAV is in a stable state before dropping; The specific steps are as follows: S301: Input the target values of the pitch angle, roll angle, and yaw angle of the predetermined attitude (denoted as θ target , φ target , ψ target ), and the actual values of the pitch angle, roll angle, and yaw angle of the current attitude (denoted as θ current , φ current , ψ current ); S302: Set the control period T, the attitude adjustment threshold ε, where the attitude adjustment threshold is used to determine whether the predetermined attitude is reached, and the stability verification time T stable ; S303: Calculate the attitude error, including: Calculate the pitch angle error, and the calculation formula is: e θ = θ target - θ current ; Calculate the roll angle error, and the calculation formula is: e φ = φ target - φ current ; Calculate the yaw angle error, and the calculation formula is: e ψ = ψ target - ψ current ; S304: Design the control law u using the PID control algorithm θ to make the pitch angle error e θ approach 0; the calculation formula is as follows: u θ = Kp θ * e θ + Ki θ * ∫ e θ dt + Kd θ * de θ / dt; S305: Design the control law u using the PID control algorithm φ such that the roll angle error e φ approaches 0. Design the control law u using the PID control algorithm ψ such that the yaw angle error e ψ approaches 0; S306: Convert the control law u θ , u φ , u ψ into the control signals of the UAV actuators and send them to the UAV. The UAV adjusts its pitch angle, roll angle and yaw angle according to the received control signals; S307: Within each control cycle T, obtain the current attitude data of the drone through the integrated sensor module and update θ current , φ current , ψ current ; S308: Determine whether the predetermined attitude is reached. If |e θ |< ε, |e φ |< ε, |e ψ |< ε, it is considered that the UAV has reached the predetermined attitude; otherwise, return to step S304 to continue adjustment; S309: After the UAV reaches the predetermined attitude, maintain this attitude for a time T; during this period, continuously monitor the attitude data of the UAV to ensure that the attitude error remains within the threshold ε; if the attitude error is always less than ε within the time T, it is considered that the UAV is in a stable state. stable Time; during this period, continuously monitor the attitude data of the UAV to ensure that the attitude error remains within the threshold ε; if stable within the time T, the attitude error is always less than ε, it is considered that the UAV is in a stable state. S310: Output result: The UAV has reached the predetermined attitude and maintains a stable state; In step S4, the UAV flies towards the dropping point according to the preset route and real-time navigation information, and monitors the distance between the UAV and the dropping point in real time through GPS. When the UAV approaches the dropping point, it gradually decelerates and hovers at the predetermined height, preparing for dropping; The specific steps are as follows: S401: The ground control station loads the preset route data into the flight control system of the UAV, including longitude and latitude coordinate points, altitude information, and flight speed; S402: After the UAV takes off, it starts the GPS to obtain the current position information of the UAV in real time; S403: The UAV calculates the shortest path or the optimal path through the Dijkstra navigation algorithm according to the preset route and real-time GPS position information, calculates the flight direction and speed adjustment amount according to the current position and the position of the target point, calculates the next target point that should be flown to currently, and adjusts the flight direction of the UAV; S404: During the flight, continuously monitor the real-time distance between the UAV and the dropping point through GPS, specifically including: Input: Real-time position data of the UAV, position data of the dropping point; Processing: Calculate the straight-line distance between two points and the actual distance according to the longitude and latitude; Output: Real-time distance between the UAV and the dropping point; S405: When the distance between the drone and the drop point is less than a preset threshold, calculate the deceleration rate according to the distance and speed relationship; when the predetermined height is reached, output a deceleration command and a hover command to the drone to control the drone to hover; S406: The drone gradually decelerates and prepares to hover at the predetermined height; S407: The drone hovers at the predetermined height, ensures the position is stable, prepares for dropping, monitors the position stability of the drone, and ensures to hover at the predetermined height for a period of time to verify the stability; after the stability verification is completed, output a signal indicating that the dropping preparation is completed; In step S5, make dropping preparations, confirm that the dropped object has been correctly loaded into the dropping device, the electric telescopic rod and the electromagnetic block are in the standby state, and according to the accurate position of the drop point, control the telescopic of the electric telescopic rod and the opening and closing of the electromagnetic block to realize the dropping of the dropped object; the specific steps are as follows: S501: Confirm the loading state of the dropped object, specifically including: Input: The loading condition of the dropping device; Processing: Through the sensor data in the dropping device, confirm whether the dropped object has been correctly and firmly loaded on the dropping component; Output: The confirmation result of the loading state; S502: Check the states of the electric telescopic rod and the electromagnetic block, specifically including: Input: The state of the electric telescopic rod, the state of the electromagnetic block; Processing: Send a query command through the signal transmission module to obtain whether the electric telescopic rod is in the initial position and whether the electromagnetic block is in the unactivated (i.e., closed) state; Output: The confirmation result of the states of the electric telescopic rod and the electromagnetic block; S503: Calculate the accurate position of the drop point, specifically including: Input: GPS data, preset drop point coordinates; Processing: Combine the current GPS position information of the drone and the preset drop point coordinates, and calculate the accurate relative position of the drone relative to the drop point through the geographic coordinate conversion algorithm; Output: The accurate relative position data of the drop point; S504: Develop a dropping strategy, specifically including: Input: The accurate position of the drop point, the current attitude of the drone; Processing: According to the position information of the drop point, the current attitude of the drone (pitch angle, roll angle, yaw angle) and the characteristics of the dropped object (weight, shape), develop a dropping strategy, including the telescopic length of the electric telescopic rod and the opening and closing timing of the electromagnetic block; Output: The dropping strategy parameters, including the telescopic amount of the electric telescopic rod and the opening and closing time of the electromagnetic block; S505: Execute the dropping action, specifically including: Input: The dropping strategy parameters; Processing: Send a control command to the electric telescopic rod to make it telescopic according to the calculated telescopic amount, and move the dropped object to the dropping position; when the dropped object reaches the predetermined dropping position, send an activation command to the electromagnetic block to make it instantly lose magnetism and release the dropped object; Output: The execution result of the dropping action and the state data during the dropping process (the telescopic condition of the electric telescopic rod, the opening and closing state of the electromagnetic block); In step S6, during and after the dropping process, the drone continues to monitor its own attitude changes in real time through the attitude sensor, the control system receives the sensor data, analyzes whether there is an attitude deviation, and if an attitude deviation is found, immediately activates the attitude feedback and adjustment mechanism, and quickly adjusts the attitude of the drone through the backstepping control method to ensure stable flight; the specific steps are as follows: S601: Real-time monitor the attitude data, specifically including: Input: The roll angle, pitch angle, and yaw angle data measured in real-time by the attitude sensor; Processing: The control system receives data from the attitude sensor at a fixed frequency; Output: The updated roll angle, pitch angle, and yaw angle values in real-time; S602: Attitude deviation detection, specifically including: Input: The attitude data measured in real-time and the preset stable attitude threshold; Processing: Compare the attitude data measured in real-time with the preset stable attitude range to determine whether there is a deviation; Output: The attitude deviation detection result, including the deviation magnitude and direction; S603: Deviation threshold judgment, specifically including: Input: The attitude deviation detection result; Processing: Set a deviation threshold. If the attitude deviation exceeds this threshold, trigger the adjustment mechanism; Output: The decision signal on whether to adjust the UAV attitude; S604: Activate the attitude feedback and adjustment mechanism, specifically including: Input: The decision signal to adjust the UAV attitude; Processing: When the decision signal is "yes", activate the attitude feedback and adjustment mechanism and prepare for attitude adjustment; Output: The signal to activate the adjustment mechanism and the initial adjustment parameters; S605: Calculate the attitude adjustment amount, specifically including: Input: The attitude data measured in real-time and the predetermined attitude target value; Processing: Use the PID control algorithm and backstepping control algorithm in step S3 to calculate the adjustment amount required to reach the predetermined attitude, including the adjustment amounts of roll angle, pitch angle, and yaw angle; Output: The attitude adjustment amount, including the roll angle adjustment amount, pitch angle adjustment amount, and yaw angle adjustment amount; S606: Execute attitude adjustment, specifically including: Input: The attitude adjustment amount; Processing: Convert the calculated attitude adjustment amount into the control signal of the UAV actuator, such as the motor speed adjustment signal or the servo control signal; Output: The actuator control signal to drive the UAV to perform attitude adjustment; S607: Adjustment effect monitoring, specifically including: Input: The attitude sensor data after the execution of the actuator control signal; Processing: Monitor the attitude data of the UAV again to evaluate the adjustment effect; Output: The adjusted attitude data and the effect evaluation result; S608: Loop adjustment until stable, specifically including: Input: The adjusted attitude data and the effect evaluation result; Processing: If the attitude has not reached the stable state, repeat the steps from S602 to S607 until the UAV attitude is stable within the preset range; Output: The state signal of the UAV flying stably; S609: Record and feedback the adjustment process, specifically including: Input: The attitude data, adjustment amount, and actuator control signal during the entire adjustment process; Processing: Record and store these data; Output: The adjustment process record data for analysis by the ground control station and R & D personnel.

2. The operation method of an unmanned aerial vehicle fixed-point delivery device according to claim 1, wherein: The drone fixed-point delivery device includes a drone frame (1); characterized in that: it further includes an integrated sensor module (2), a signal transmission module (3), a bracket (4) and a delivery component; an integrated sensor module (2) is arranged above the drone frame (1), a signal transmission module (3) is arranged above the drone frame (1), a bracket (4) is arranged below the drone frame (1), and a delivery component is arranged below the drone frame (1); the delivery component includes an electric telescopic rod (501), an electromagnet block (502), a metal connecting block (503) and a hanging ring (504); an electric telescopic rod (501) is arranged below the drone frame (1), one end of the electric telescopic rod (501) is provided with an electromagnet block (502), an electromagnet block (502) is arranged below the electromagnet block (502), a metal connecting block (503) is arranged below the metal connecting block (503), and a hanging ring (504) is arranged below the metal connecting block (503); the integrated sensor module (2) includes a gyroscope, an accelerometer and a magnetometer; the gyroscope is used to measure in real time the angular velocity of the drone around its three main axes, namely the roll axis, the pitch axis and the yaw axis, so as to provide information on the change of the attitude angle of the drone; the accelerometer is used to measure the linear acceleration of the drone in three axial directions, namely front-back, left-right, up-down, and the components of the gravitational acceleration in the drone coordinate system; the magnetometer is used to measure the three components of the geomagnetic field in the drone coordinate system to determine the heading angle of the drone, that is, the yaw angle; the data of the magnetometer is combined with the data of the gyroscope and the accelerometer to describe the attitude and heading of the drone and provide precise navigation information for fixed-point delivery; the signal transmission module (3) is arranged above the drone frame (1) and is electrically connected to the integrated sensor module (2) and the delivery component; the signal transmission module (3) includes: A data receiving unit for receiving real-time data from the integrated sensor module (2), including the angular velocity data measured by the gyroscope, the linear acceleration and gravitational acceleration data measured by the accelerometer, and the geomagnetic field data measured by the magnetometer; A data processing unit connected to the data receiving unit for preprocessing the received data, including data verification, format conversion and preliminary filtering to ensure the accuracy and reliability of the data; A wireless communication sub-module connected to the data processing unit, responsible for encoding the preprocessed data and the instructions from the control center and sending them to the ground control station wirelessly, and at the same time receiving the control instructions and parameter adjustment information from the ground control station; A control instruction decoding unit connected to the wireless communication sub-module for decoding the received control instructions and converting them into operation signals executable by the delivery component, including starting / stopping the electric telescopic rod (501), activating / closing the electromagnet block (502); A status feedback unit for monitoring the working status of the signal transmission module (3) itself, including the communication link quality, battery power, data transmission rate, and feeding back these status information to the ground control station through the wireless communication sub-module.

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