Agricultural protection unmanned aerial vehicle mist droplet drift suppression device and method

Abstract

The application relates to a plant protection unmanned aerial vehicle mist droplet drift inhibition device and method, and belongs to the technical field of agricultural plant protection. The device comprises a plant protection unmanned aerial vehicle main body, a data collection system, a control system and a spraying system are arranged on the plant protection unmanned aerial vehicle main body, the control system is connected with the data collection system and the spraying system respectively, the data collection system comprises an RTK module, a wind speed and direction sensor and a laser particle size instrument; the spraying system comprises a liquid supply device and connecting frames symmetrically arranged on the two sides of the plant protection unmanned aerial vehicle main body, a rotating mechanism is arranged on the connecting frame, a horizontal moving mechanism, a rudder platform and a centrifugal spray head are sequentially arranged on the lower end of the rotating mechanism from top to bottom, the rotating mechanism is used for driving the horizontal moving mechanism to rotate, the horizontal moving mechanism is used for driving the rudder platform to horizontally move, and the liquid supply device is used for providing liquid medicine to the centrifugal spray head. The application realizes multi-phase regulation of position, angle, pressure and particle size, so that the complex airflow such as oblique wind and turbulent flow can be coped with, and the drift inhibition effect is improved.

Description

Technical Field

[0001] This invention relates to the field of agricultural plant protection technology, and in particular to a device and method for suppressing droplet drift in plant protection drones. Background Technology

[0002] Agricultural drones have been widely used in the prevention and control of crop diseases and pests due to their high operating efficiency and strong adaptability. However, droplet drift has always been the core bottleneck restricting precision application. This not only leads to a large amount of pesticide waste, but may also pollute nearby crops, water sources and non-target organisms, causing the risk of pesticide residue exceeding the standard.

[0003] Existing patent CN108812591B discloses a distributed agricultural drone spraying system, which adopts a "airborne + ground" distributed environmental monitoring system and achieves parameter control through pressure adjustment and angle adjustment devices. However, it has the following problems: it relies on ground environmental monitoring devices (which need to be fixedly deployed), which limits the mobility of drone operations and makes it difficult to adapt to mobile operations in complex terrains such as mountains and hills; the control only covers two dimensions: pressure and angle, and does not involve the coordinated adjustment of nozzle spatial position and droplet size, making it difficult to cope with complex airflows such as oblique winds and turbulence. Summary of the Invention

[0004] In view of this, the purpose of the present invention is to provide a device and method for suppressing droplet drift in agricultural drones.

[0005] The technical solution adopted by the present invention to solve the above-mentioned technical problems is as follows: a plant protection drone droplet drift suppression device, including a plant protection drone body, a data collection system, a control system and a spraying system on the plant protection drone body, the control system being connected to the data collection system and the spraying system respectively, the data collection system including an RTK module, a wind speed and direction sensor and a laser particle size analyzer; the spraying system including a liquid supply device and connecting frames symmetrically arranged on both sides of the plant protection drone body, the connecting frames being equipped with a rotating mechanism, the lower end of the rotating mechanism being provided with a horizontal moving mechanism, a servo platform and a centrifugal nozzle from top to bottom, the rotating mechanism being used to drive the horizontal moving mechanism to rotate, the horizontal moving mechanism being used to drive the servo platform to move horizontally, and the liquid supply device being used to supply liquid to the centrifugal nozzle.

[0006] Furthermore, the wind speed and direction sensor is located at the front of the plant protection drone body, there are two RTK modules, which are located at the front of the plant protection drone body and on both sides of the wind speed and direction sensor, and the laser particle size analyzer is located at the rear of the plant protection drone body.

[0007] Furthermore, the connecting frame includes a bracket and a positioning plate disposed at the free end of the bracket, and a rotating mechanism is disposed at the lower end of the positioning plate;

[0008] The rotating mechanism includes a rotating frame, a rotary motor mounted on the rotating frame, and a connecting plate mounted on the end of the output shaft of the rotary motor. The horizontal moving mechanism includes a horizontal moving linear module, which is mounted on the lower end of the connecting plate, and a servo platform is mounted on the lower end of the horizontal moving linear module.

[0009] Furthermore, the servo platform includes a rotary servo, a rotating component at the lower end of the output shaft of the rotary servo, a pitch servo at the lower end of the rotating component, a U-shaped fixed plate on the output shaft of the pitch servo, a centrifugal nozzle at the lower end of the U-shaped fixed plate, and the pitch servo is used to drive the U-shaped fixed plate to swing around the output shaft axis of the pitch servo.

[0010] Furthermore, the liquid supply device includes a liquid supply tank installed on the main body of the plant protection drone, a liquid supply tank equipped with a liquid pressure pump, the liquid supply pressure pump being connected to a centrifugal nozzle via a liquid delivery pipeline, a pressure sensor being installed on the liquid delivery pipeline, and a centrifugal motor being installed inside the centrifugal nozzle, the centrifugal motor being a speed-regulating motor.

[0011] Furthermore, the control system includes a control box, which contains an industrial computer, a microcontroller, and a data transmission and image transmission module. The data transmission and image transmission module is connected to a cloud server, and the industrial computer is connected to the data collection system, the microcontroller, and the data transmission and image transmission module.

[0012] Furthermore, it also includes a digital twin system, which includes virtual twin units, including geometric twins, flow field twins, spray twins, and environmental twins. The digital twin system is connected to an industrial control computer.

[0013] Among them, the geometric twin is a three-dimensional geometric model of the main body of the agricultural drone constructed using SolidWorks;

[0014] The flow field twin uses ANSYS Fluent coupled RANS equations and the standard k-ωSST turbulence model to simulate the coupling results of the rotor downwash flow field and the ambient wind field.

[0015] The spray twin uses a multiphase flow method to simulate the atomization process of a centrifugal nozzle and a discrete phase model to simulate the droplet motion of the centrifugal nozzle.

[0016] Environmental twins integrate field meteorological data to correct simulation boundary conditions;

[0017] This application also provides a method for suppressing droplet drift using the above-mentioned agricultural drone droplet drift suppression device, including the following steps:

[0018] S1. The data collection system collects drone-related data in real time, including drone flight status data, wind speed and direction data, and droplet size data.

[0019] S2. Construct a virtual twin unit. The virtual twin unit predicts state drift based on the collected UAV-related data, outputs the optimal control parameters, and feeds them back to the control system.

[0020] S3. The control system adjusts the position of the centrifugal nozzle, the spray angle, the initial velocity of the droplets, and the droplet size according to the optimal control parameters to achieve droplet drift suppression.

[0021] Preferably, the UAV flight status data includes pitch angle, roll angle, heading angle, flight speed, and flight altitude, which are obtained through an RTK module.

[0022] Preferably, in step S3, the position of the centrifugal nozzle is adjusted by adjusting the rotating mechanism and the horizontal moving mechanism.

[0023] The spray angle of the centrifugal nozzle can be adjusted by adjusting the servo motor platform.

[0024] The droplet size of the centrifugal nozzle can be adjusted by regulating the speed of the centrifugal motor.

[0025] The initial velocity of the droplets from the centrifugal nozzle can be adjusted by regulating the pressure of the hydraulic pump.

[0026] The beneficial effects of this application are as follows: 1. This application sets up a data collection system integrated into the main body of the agricultural drone, which does not rely on ground monitoring, making it easier to adapt to mobile operations in complex terrains such as mountains and hills, and improving the mobility of the main body of the agricultural drone.

[0027] 2. This application achieves multi-phase control of position, angle, pressure and particle size by setting up a rotating mechanism, a horizontal moving mechanism and a servo platform to adjust the position, spray angle, initial velocity of droplets and droplet size of centrifugal nozzles, thereby facilitating the handling of complex airflows such as oblique winds and turbulence and improving the drift suppression effect.

[0028] 3. This application constructs a virtual twin unit, which predicts state drift based on collected UAV data and generates optimal control parameters. The control system adjusts the position of the centrifugal nozzle, the spray angle, the initial velocity of the droplets, and the droplet size according to the optimal control parameters, thereby achieving droplet drift suppression and improving the accuracy of droplet drift suppression. Attached Figure Description

[0029] Figure 1 This is the isometric drawing of this application.

[0030] Figure 2 This is a front view of this application.

[0031] Figure 3 This is a schematic diagram of the rotating mechanism of this application.

[0032] Figure 4 This is a schematic diagram of the horizontal movement mechanism of this application.

[0033] Figure 5 This is a schematic diagram of the servo platform of this application.

[0034] Illustration labels: 1. Main body of agricultural drone, 2. RTK module, 3. Wind speed and direction sensor, 4. Connecting frame, 4-1. Bracket, 4-2. Positioning plate, 5. Rotating mechanism, 5-1. Rotating frame, 5-2. Rotating motor, 5-3. Connecting plate, 6. Horizontal movement mechanism, 6-1. Slide rail, 6-2. Slider, 6-3. Mounting plate, 7. Servo platform, 7-1. Rotating servo, 7-2. Rotating component, 7-3. Pitch servo, 7-4. U-shaped fixing plate, 8. Centrifugal nozzle, 9. Liquid pressure pump, 10. Control box, 11. Laser particle size analyzer. Detailed Implementation

[0035] 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, in the description of this invention, unless otherwise stated, "a plurality of" means two or more; the terms "upper," "lower," "left," "right," "inner," "outer," "front end," "rear end," "head," "tail," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings, and are only for the convenience of describing the invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of the invention. Furthermore, the terms "first," "second," "third," etc., are used for descriptive purposes only and should not be construed as indicating or implying relative importance.

[0036] Please see Figure 1-5 This invention provides a device for suppressing droplet drift in agricultural drones, comprising an agricultural drone body 1, a data collection system, a control system, and a spraying system on the agricultural drone body 1, the control system being connected to the data collection system and the spraying system respectively, the data collection system including an RTK module 2, a wind speed and direction sensor 3, and a laser particle size analyzer 11; the spraying system including a liquid supply device and connecting frames 4 symmetrically arranged on both sides of the agricultural drone body 1, the connecting frames 4 being provided with a rotating mechanism 5, the lower end of the rotating mechanism 5 being provided with a horizontal moving mechanism 6, a servo platform 7, and a centrifugal nozzle 8 from top to bottom, the rotating mechanism 5 being used to drive the horizontal moving mechanism 6 to rotate, the horizontal moving mechanism 6 being used to drive the servo platform 7 to move horizontally, and the liquid supply device being used to supply liquid to the centrifugal nozzle 8.

[0037] The system includes a wind speed and direction sensor 3 for collecting wind speed and direction data, and a laser particle size analyzer 11 for acquiring median droplet size data. The wind speed and direction sensor 3 is located at the front of the main body 1 of the agricultural drone. Two RTK modules 2 are located at the front of the main body 1 and on either side of the wind speed and direction sensor 3. The laser particle size analyzer 11 is located at the rear of the main body 1. The connecting frame 4 includes a support 4-1 and a positioning plate 4-2 located at the free end of the support 4-1. A rotating mechanism 5 is located at the lower end of the positioning plate 4-2. The rotating mechanism 5 includes a rotating frame 5-1, a rotating motor 5-2 mounted on the rotating frame 5-1, and a connecting plate 5-3 located at the output shaft end of the rotating motor 5-2. The rotating motor 5-2 is a servo motor. The horizontal movement mechanism 6 includes a horizontal linear movement module located at the lower end of the connecting plate 5-3, and a servo platform 7 located at the lower end of the horizontal linear movement module. A horizontally moving linear module typically includes a slide rail 6-1 extending horizontally, a slider 6-2 driven by a motor mounted on the slide rail 6-1, a mounting plate 6-3 at the lower end of the slider 6-2, and a servo platform 7 mounted at the lower end of the mounting plate 6-3.

[0038] Specifically, the servo platform 7 includes a fixed frame and a rotary servo 7-1 mounted on the fixed frame. A rotating component 7-2 is located at the lower end of the output shaft of the rotary servo 7-1. The rotating component 7-2 is rotatably mounted on the fixed frame and is disc-shaped. A pitch servo 7-3 is located at the lower end of the rotating component 7-2. A U-shaped fixed plate 7-4 is mounted on the output shaft of the pitch servo 7-3. A centrifugal nozzle 8 is located at the lower end of the U-shaped fixed plate 7-4. The pitch servo 7-3 drives the U-shaped fixed plate 7-4 to swing around the output shaft axis of the pitch servo 7-3. Both the rotary servo 7-1 and the pitch servo 7-3 are metal gear servos.

[0039] The liquid supply device includes a liquid supply tank mounted on the main body 1 of the agricultural drone. The liquid supply tank is equipped with a liquid supply pressure pump 9, which is connected to a centrifugal nozzle 8 via a delivery pipeline. A pressure sensor is installed on the delivery pipeline. The centrifugal nozzle 8 contains a centrifugal motor, which is a speed-adjustable motor. The centrifugal motor's rotation speed is 1000-6000 rpm, and the droplet size is adjustable from 50-300 μm. The liquid supply pressure pump's output pressure is 0.3-1.2 MPa, and the initial droplet velocity is adjustable from 8-20 m / s.

[0040] In addition, the control system includes a control box 10, which houses an industrial computer, a microcontroller, and a data transmission and image transmission module. The data transmission and image transmission module communicates with a cloud server. The industrial computer is connected to the data collection system, the microcontroller, and the data transmission and image transmission module. The data transmission and image transmission module uploads UAV-related data collected by the data collection system to the cloud server. All UAV-related data is fused using Kalman filtering to eliminate noise.

[0041] It also includes a digital twin system, which comprises virtual twin units, including geometric twins, flow field twins, spray twins, and environmental twins. The digital twin system is connected to an industrial control computer. The geometric twin is a 3D geometric model of the agricultural drone's main body 1, constructed using SolidWorks. The data collection system, control system, and spraying system of the agricultural drone's main body 1 are also included in this 3D geometric model. The cloud server contains the digital twin system.

[0042] The flow field twin uses ANSYS Fluent coupled with RANS equations and the standard k-ωSST turbulence model. A sliding mesh is used to simulate rotor rotation speeds of 1000-6000 rpm. Inlet velocity is set to 0-15 m / s, wind direction to 0-360°, pressure outlet to be set, and a no-slip wall (including the fuselage and ground) is included. The coupling results of the rotor downwash flow field and the ambient wind field are simulated, and the output airflow velocity gradient distribution is consistent with the original flow field simulation parameters. The spray twin uses a multiphase flow method to simulate the atomization process of centrifugal nozzle 8. A discrete phase model is used to define droplet parameters—particle size 50-300 μm, initial velocity 8-20 m / s—and to simulate the droplet trajectory of centrifugal nozzle 8. The environmental twin integrates field meteorological data to correct simulation boundary conditions: it integrates field microclimate parameter interfaces, imports wind speed and direction data in real time, and corrects flow field simulation boundary conditions, such as turbulence intensity of 5% and ground roughness z=0.01m, to adapt to wheat field scenarios and make up for the limitations of the original model that only relies on fixed parameters.

[0043] This application also provides a method for suppressing fog drift using the above-mentioned plant protection drone fog drift suppression device, including the following steps:

[0044] S1. The data collection system collects relevant data from the UAV in real time, including UAV flight status data, wind speed and direction data, and droplet size data. The UAV flight status data includes pitch angle, roll angle, yaw angle, flight speed, and flight altitude, which are obtained through RTK module 2.

[0045] S2. Construct a virtual twin unit. The virtual twin unit predicts state drift based on the collected UAV-related data, outputs the optimal control parameters, and feeds them back to the control system.

[0046] S3. The control system adjusts the position, spray angle, initial velocity of droplets, and droplet size of the centrifugal nozzle 8 according to the optimal control parameters to achieve droplet drift suppression.

[0047] In step S3, the position of the centrifugal nozzle 8 is adjusted by regulating the rotating mechanism 5 and the horizontal moving mechanism 6; the spray angle of the centrifugal nozzle 8 is adjusted by regulating the servo platform 7; the droplet size of the centrifugal nozzle 8 is adjusted by regulating the speed of the centrifugal motor; and the initial velocity of the droplets from the centrifugal nozzle 8 is adjusted by regulating the pressure of the liquid circuit pressure pump 9. After the operation, actual sedimentation data is collected using field water-sensitive paper and compared with the virtual prediction results to calibrate and optimize the digital twin model, continuously improving prediction accuracy and control effect.

[0048] In step S3 of this application, when adjusting the position, spray angle, initial droplet velocity, and droplet size of the centrifugal nozzle 8, a four-level progressive control logic is adopted: Level 1 control: suppressing drift by adjusting the spray angle of the centrifugal nozzle 8; Level 2 control: suppressing drift by moving the position of the centrifugal nozzle 8; adjusting the initial droplet velocity by adjusting the pressure of the liquid circuit pressure pump 9, thereby shortening the droplet dwell time and achieving the effect of suppressing drift; Level 4 control: suppressing drift by adjusting the rotation speed of the centrifugal motor and the flight speed of the main body 1 of the agricultural drone.

[0049] It should be noted that the above embodiments are only used to illustrate the present invention, but the present invention is not limited to the above embodiments. Any simple modifications, equivalent changes and alterations made to the above embodiments based on the technical essence of the present invention shall fall within the protection scope of the present invention.

Claims

1. A method for suppressing droplet drift based on a plant protection drone's droplet drift suppression device, characterized in that, The suppression device includes a plant protection drone body (1), which is equipped with a data collection system, a control system and a spraying system. The control system is connected to the data collection system and the spraying system respectively. The data collection system includes two RTK modules (2), a wind speed and direction sensor (3) and a laser particle size analyzer (11). The spraying system includes a liquid supply device and a connecting frame (4) symmetrically arranged on both sides of the main body (1) of the plant protection drone. A rotating mechanism (5) is provided on the connecting frame (4). From top to bottom, the lower end of the rotating mechanism (5) is provided with a horizontal moving mechanism (6), a servo platform (7) and a centrifugal nozzle (8). The rotating mechanism (5) is used to drive the horizontal moving mechanism (6) to rotate. The horizontal moving mechanism (6) is used to drive the servo platform (7) to move horizontally. The liquid supply device is used to supply liquid to the centrifugal nozzle (8). The liquid supply device includes a liquid supply tank installed on the main body (1) of the plant protection drone. The liquid supply tank is equipped with a liquid pressure pump (9). The liquid pressure pump (9) is connected to the centrifugal nozzle (8) through a liquid delivery pipeline. A pressure sensor is installed on the liquid delivery pipeline. The centrifugal nozzle (8) contains a centrifugal motor, which is a speed-regulating motor. The control system includes a control box (10), which contains an industrial computer, a microcontroller and a data transmission and image transmission module. The data transmission and image transmission module is connected to a cloud server. The industrial computer is connected to the data collection system, the microcontroller and the data transmission and image transmission module respectively. It also includes a digital twin system, which includes virtual twin units, including geometric twins, flow field twins, spray twins, and environmental twins. The digital twin system is connected to an industrial control computer. Among them, the geometric twin is constructed using SolidWorks to create a three-dimensional geometric model of the main body (1) of the agricultural drone; The flow field twin uses ANSYS Fluent coupled RANS equations and the standard k-ωSST turbulence model to simulate the coupling results of the rotor downwash flow field and the ambient wind field. The spray twin uses a multiphase flow method to simulate the atomization process of the centrifugal nozzle (8) and a discrete phase model to simulate the droplet motion of the centrifugal nozzle (8); Environmental twins integrate field meteorological data to correct simulation boundary conditions; The suppression method includes the following steps: S1. The data collection system collects drone-related data in real time, including drone flight status data, wind speed and direction data, and droplet size data. S2. Construct a virtual twin unit. The virtual twin unit predicts state drift based on the collected UAV-related data, outputs the optimal control parameters, and feeds them back to the control system. S3. The control system adjusts the position, spray angle, initial velocity and droplet size of the centrifugal nozzle (8) according to the optimal control parameters to achieve droplet drift suppression. The UAV flight status data includes pitch angle, roll angle, heading angle, flight speed and flight altitude, which are obtained through RTK module (2); In step S3, the position of the centrifugal nozzle (8) is adjusted by adjusting the rotating mechanism (5) and the horizontal moving mechanism (6); The spray angle of the centrifugal nozzle (8) can be adjusted by adjusting the servo platform (7); The droplet size of the centrifugal nozzle (8) can be adjusted by adjusting the speed of the centrifugal motor. The initial velocity of the droplets in the centrifugal nozzle (8) can be adjusted by regulating the pressure of the liquid circuit pressure pump (9).

2. The suppression method according to claim 1, characterized in that, The wind speed and direction sensor (3) is located at the front of the plant protection drone body (1), the two RTK modules (2) are located at the front of the plant protection drone body (1) and on both sides of the wind speed and direction sensor (3), and the laser particle size analyzer (11) is located at the rear of the plant protection drone body (1).

3. The suppression method according to claim 1, characterized in that, The connecting frame (4) includes a bracket (4-1) and a positioning plate (4-2) disposed at the free end of the bracket (4-1), and the rotating mechanism (5) is disposed at the lower end of the positioning plate (4-2); The rotating mechanism (5) includes a rotating frame (5-1), a rotating motor (5-2) mounted on the rotating frame (5-1), and a connecting plate (5-3) mounted on the output shaft end of the rotating motor (5-2). The horizontal moving mechanism (6) includes a horizontal moving linear module, which is mounted on the lower end of the connecting plate (5-3). The servo platform (7) is mounted on the lower end of the horizontal moving linear module.

4. The suppression method according to claim 3, wherein the servo platform (7) includes a rotary servo (7-1), a rotating component (7-2) is provided at the lower end of the output shaft of the rotary servo (7-1), a pitch servo (7-3) is provided at the lower end of the rotating component (7-2), a U-shaped fixed plate (7-4) is provided on the output shaft of the pitch servo (7-3), a centrifugal nozzle (8) is provided at the lower end of the U-shaped fixed plate (7-4), and the pitch servo (7-3) is used to drive the U-shaped fixed plate (7-4) to swing around the output shaft axis of the pitch servo (7-3).

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