Agricultural unmanned aerial vehicle centrifugal nozzle spacing adjustment control method

Abstract

The application provides an agricultural unmanned aerial vehicle centrifugal nozzle spacing adjustment control method, and mainly relates to the unmanned aerial vehicle control field. The method provided by the application is used for adjusting the spacing of the unmanned aerial vehicle nozzles in the spraying operation, comprising determining the initial speed of the mist droplets and the air resistance coefficient according to the rotating speed of the atomizing disc, the particle size of the mist droplets, the density of the pesticide and the like; determining the first wind speed of the down pressure wind field generated by the rotor according to the first load amount of the unmanned aerial vehicle, the number of the rotor and the diameter of the rotor; determining the landing time length of the mist droplets according to the operation height of the agricultural unmanned aerial vehicle; thereby determining the first spacing of the centrifugal nozzles according to the landing time length; and adjusting the relative positions between the centrifugal nozzles of the agricultural unmanned aerial vehicle according to the first spacing. The application can not only improve the operation efficiency of the agricultural unmanned aerial vehicle, reduce the waste of the pesticide and the labor cost, and provide new technical support for the agricultural production through the environment-friendly and efficient spraying mode.

Description

Technical Field

[0001] This application relates to the field of unmanned aerial vehicle (UAV) control, and more specifically, to a method for adjusting and controlling the spacing of centrifugal nozzles of agricultural UAVs. Background Technology

[0002] Agricultural drones have broad application prospects in agricultural spraying and are currently commonly used for crop protection and nutrient regulation. Agricultural drones can perform precise spraying, evenly distributing chemical agents and nutrients onto the crop surface to protect crops, regulate their growth, reduce losses, and increase yields. Examples include spraying pesticides on fruit trees, vegetables, corn, and rice; and spraying liquid fertilizers, trace elements, and other hormones to improve crop quality and growth efficiency.

[0003] Most drones use fixed-spaced nozzles for agricultural spraying. However, due to differences in crop growth stages and environments, this fixed-spaced nozzle layout can lead to poor spraying efficiency, pesticide waste, or inconvenience. Furthermore, the drone's flight altitude also affects the nozzle spacing. Higher altitudes require larger nozzle spacing to ensure even spraying of the pesticide across the target area. Lower altitudes require smaller nozzle spacing to ensure uniform distribution of the sprayed pesticide within the coverage area.

[0004] How to make the spacing between nozzles adjustable in a precise and quantitative manner according to actual operating conditions, so as to provide a more flexible, efficient and controllable solution for agricultural operations, has become a hot research topic in recent years. Summary of the Invention

[0005] This application provides a method for adjusting and controlling the spacing of centrifugal nozzles on agricultural drones. By collecting and analyzing information such as the type of spray agent, the rotation speed of the atomizing disc, the drone's flight altitude, and the wind speed of the drone's rotor, and performing real-time calculations, the optimal spacing of the drone's centrifugal nozzles is calculated to ensure uniform and thorough spraying of the agent. This application not only improves the operational efficiency of agricultural drones and reduces pesticide waste and labor costs, but also aims to provide new technical support for agricultural production through an environmentally friendly and efficient spraying method.

[0006] In one aspect, a method for adjusting and controlling the spacing of centrifugal nozzles of an agricultural drone is provided. The centrifugal nozzle includes an atomizing disc with teeth on its edge. The atomizing disc rotates so that the teeth strike the pesticide, which is then atomized into droplets and sprayed out from the centrifugal nozzle. The adjustment method specifically includes the following steps: acquiring operational data of the agricultural drone, including droplet size, atomizing disc rotation speed, tooth radius, pesticide density, number of drone rotors, and rotor diameter; determining the initial velocity of the droplets along a first direction based on the atomizing disc rotation speed and tooth radius, wherein the first direction is tangent to the atomizing disc and perpendicular to the direction of gravity; determining the air resistance coefficient of the droplets based on the droplet size and pesticide density; acquiring the first load of the agricultural drone at a first moment, and determining the first wind speed of the downforce wind field generated by the rotors based on the first load, the number of drone rotors, and rotor diameter; acquiring the first operating altitude of the agricultural drone at a first moment, and determining the first descent time of the droplets based on the first operating altitude, first wind speed, and air resistance coefficient; determining the first distance the droplets are sprayed along the first direction based on the first descent time, initial velocity, and air resistance coefficient; determining the first spacing between the centrifugal nozzles at a first moment based on the first distance; and adjusting the relative position between the centrifugal nozzles of the agricultural drone based on the first spacing.

[0007] Based on this technical solution, by acquiring the set parameters of the drone and / or data transmitted through sensors installed on the drone, the descent time of the sprayed droplets under the influence of the drone's rotor wind field can be determined by sensing the drone's flight altitude. The diffusion distance of the droplets in the initial velocity direction can be calculated based on the descent time, and the spacing between the drone's centrifugal nozzles can be adjusted according to the diffusion distance. This application not only improves the operational efficiency of agricultural drones and reduces pesticide waste and labor costs, but also aims to provide new technical support for agricultural production through an environmentally friendly and efficient spraying method.

[0008] In conjunction with the first aspect, in some implementations of the first aspect, determining the first descent time of the fog droplets includes:

[0009]

[0010] Where H is the first working height, V S Let H be the first wind speed and μ be the air resistance coefficient. By obtaining the first operating altitude H of the agricultural drone at the first moment, the first descent time t of the fog droplets is determined.

[0011] Based on this technical solution, the descent time of sprayed droplets under the influence of the drone rotor wind field can be calculated by calculating and / or detecting the drone's flight altitude. It is known that the descent time is related to the drone's flight altitude, the wind speed of the downforce wind field generated by the rotor, and the air resistance coefficient experienced by the droplets themselves. The diffusion distance of the droplets in the initial velocity direction is calculated based on the descent time, and the spacing between the drone's centrifugal nozzles is adjusted accordingly. This application not only improves the operational efficiency of agricultural drones and reduces pesticide waste and labor costs, but also aims to provide new technical support for agricultural production through an environmentally friendly and efficient spraying method.

[0012] In conjunction with the first aspect, in some implementations of the first aspect, determining the first distance of the droplet includes:

[0013]

[0014] Among them, R f V represents the first distance the droplets travel along the first direction. X Let μ be the initial velocity of the droplet, μ be the air resistance coefficient, and t be the first droplet fall time. The first distance R of the droplet sprayed along the first direction is determined based on the value of the first droplet fall time t. f The value of .

[0015] Based on this technical solution, the distance the droplets travel along their initial velocity direction can be calculated by measuring the droplet's droplet fall time. The spraying distance along the initial velocity direction is related to the droplet's initial velocity and the air resistance coefficient it experiences. The spacing between the centrifugal nozzles of the drone can be adjusted according to the calculated diffusion distance. This application not only improves the operational efficiency of agricultural drones and reduces pesticide waste and labor costs, but also aims to provide new technical support for agricultural production through an environmentally friendly and efficient spraying method.

[0016] In conjunction with the first aspect, in certain implementations of the first aspect, determining the first spacing of the centrifugal nozzles includes:

[0017] N≤2R f

[0018] Where N is the first pitch of the drone nozzle, and R f The first distance at which the droplets are sprayed in the first direction.

[0019] Based on this technical solution, the spacing between two nozzles is set by calculating the spraying distance of the droplets in the first direction. This application can adjust the spacing between nozzles according to different altitudes during drone operation, and can also set the drone's operating altitude according to the height of the crops, thereby automatically adjusting the spacing between the nozzles. This application not only improves the operating efficiency of agricultural drones and reduces pesticide waste and labor costs, but also aims to provide new technical support for agricultural production through an environmentally friendly and efficient spraying method.

[0020] In conjunction with the first aspect, in certain implementations of the first aspect, determining the droplet size includes:

[0021] d=An+Bf+C

[0022] Where d is the droplet size, n is the rotational speed of the atomizing disc, f is the flow rate of the atomizing disc, and A, B, and C are undetermined coefficients; determining the undetermined coefficients involves fitting the measured droplet size d values.

[0023] Based on this technical solution, the droplet size value obtained through experimental testing is fitted with two dependent variables: the rotation speed and flow rate of the atomizing disc. This determines the undetermined coefficients of the fitting formula, resulting in a formula for calculating the droplet size. During drone operations, the droplet size can be determined based on the rotation speed and flow rate of the atomizing disc, thereby determining the droplet drop time and corresponding spraying distance. This application not only improves the operational efficiency of agricultural drones and reduces pesticide waste and labor costs, but also aims to provide new technical support for agricultural production through an environmentally friendly and efficient spraying method.

[0024] In conjunction with the first aspect, in certain implementations of the first aspect, determining the air resistance coefficient of the fog droplets includes:

[0025]

[0026] Where μ is the air resistance coefficient, d is the droplet size, and ρ is the density of the reagent.

[0027] Based on this technical solution, the air resistance coefficient of the droplets sprayed by the centrifugal nozzle is calculated by considering the droplet size and the density of the sprayed agent. During drone operations, the air resistance coefficient of the droplets can be determined according to different types of agents, thereby allowing for more precise adjustment of the nozzle spacing. This application not only improves the operational efficiency of agricultural drones and reduces agent waste and labor costs, but also aims to provide new technical support for agricultural production through an environmentally friendly and efficient spraying method.

[0028] In conjunction with the first aspect, in certain implementations of the first aspect, determining the first wind speed of the downforce generated by the rotor includes:

[0029]

[0030] Among them, V S Let M be the first wind speed, D be the number of rotors of the drone, L be the first payload of the drone, and g be the acceleration due to gravity.

[0031] Based on this technical solution, the wind speed of the downforce wind field generated by the rotors during drone operation is calculated by considering the number and diameter of the drone's rotors and the drone's payload. This allows for the determination of the descent speed of the sprayed droplets under the influence of the wind field, and further refinement of the spacing between nozzles. This application not only improves the operational efficiency of agricultural drones and reduces pesticide waste and labor costs, but also aims to provide new technical support for agricultural production through an environmentally friendly and efficient spraying method.

[0032] In conjunction with the first aspect, in some implementations of the first aspect, when the agricultural drone is at the second moment, the method further includes acquiring the second payload and the second operating altitude of the agricultural drone at the second moment; determining the second descent duration of the droplets based on the second operating altitude; determining the second distance the droplets are sprayed along the first direction and the second spacing between the centrifugal nozzles based on the second descent duration; and adjusting the relative positions between the centrifugal nozzles of the agricultural drone based on the second spacing. The second moment refers to a time after the first moment, and includes moments when the payload and / or operating altitude of the agricultural drone change.

[0033] In a second aspect, a computer-readable storage medium is provided, comprising a computer program that, when executed on a computer device, causes a processing unit in the computer device to perform the method of the first aspect or various implementations thereof.

[0034] Thirdly, a chip is provided, which includes a processor and a data interface. The processor reads instructions stored in memory through the data interface to execute the methods of the first aspect or various implementations of the first aspect.

[0035] Fourthly, a control system for adjusting the spacing of centrifugal nozzles is provided. This control system is installed in an agricultural drone, which further includes a rotor, a storage tank, and at least one set of centrifugal nozzles. The rotor controls the flight of the agricultural drone by rotation, the storage tank stores the pesticide to be sprayed, the centrifugal nozzles spray the pesticide, and the control system executes the method of the first aspect or various implementations thereof.

[0036] Fifthly, an agricultural drone is provided, comprising a rotor, a storage tank, at least one set of centrifugal nozzles, and a controller. The rotor controls the drone's flight operations by rotation; the storage tank stores pesticides to be sprayed; the centrifugal nozzles spray the pesticides; and the controller executes the method of the first aspect or various implementations thereof. The controller is also used to adjust the relative positions of the at least one set of centrifugal nozzles according to a first spacing determined by the first aspect or various implementations thereof. Attached Figure Description

[0037] Figure 1 This is a schematic diagram of a commonly used agricultural drone structure provided in the embodiments of this application.

[0038] Figure 2 This is a schematic diagram of a spraying operation using an agricultural drone, as provided in an embodiment of this application.

[0039] Figure 3 This is a flowchart illustrating a method for adjusting the spacing of centrifugal nozzles of an agricultural drone, as provided in an embodiment of this application.

[0040] Figure 4 This is a schematic diagram illustrating a method for generating droplets sprayed by an agricultural drone, as provided in an embodiment of this application.

[0041] Figure 5 This is a schematic diagram of the force analysis of droplets during spraying operations by an agricultural drone, provided in an embodiment of this application. Detailed Implementation

[0042] The technical solutions in the embodiments of this application will now be described with reference to the accompanying drawings.

[0043] The terminology used in the implementation section of this application is for the purpose of explaining specific embodiments of this application only, and is not intended to limit this application.

[0044] In this application, the terms "first," "second," and "third" are used to distinguish identical or similar items that have essentially the same function. It should be understood that there is no logical or temporal dependency between "first," "second," and "third," nor are they limited in quantity or execution order.

[0045] In the embodiments of this application, the words "exemplary," "for example," etc., are used to indicate that they are examples, illustrations, or descriptions. Any embodiment or design that is described as "exemplary" in this application should not be construed as being more preferred or advantageous than other embodiments or design options. Specifically, the use of the term "exemplary" is intended to present the concept in a concrete manner.

[0046] References to "one embodiment" or "some embodiments" as described in this specification mean that one or more embodiments of this application include a specific feature, structure, or characteristic described in connection with that embodiment. Therefore, the phrases "in one embodiment," "in some embodiments," "in other embodiments," "in still other embodiments," etc., appearing in different parts of this specification do not necessarily refer to the same embodiment, but rather mean "one or more, but not all, embodiments," unless otherwise specifically emphasized. The terms "comprising," "including," "having," and variations thereof mean "including but not limited to," unless otherwise specifically emphasized.

[0047] In this application, "at least one" means one or more, and "more than one" means two or more.

[0048] It should be understood that the specific examples in this document are only intended to help those skilled in the art better understand the embodiments of this application, and are not intended to limit the scope of the embodiments of this application.

[0049] It should also be understood that the various implementation methods described in this specification can be implemented individually or in combination, and the embodiments of this application are not limited in this respect.

[0050] Unless otherwise stated, all technical and scientific terms used in the embodiments of this application have the same meaning as commonly understood by one of ordinary skill in the art. The terminology used in this application is for the purpose of describing particular embodiments only and is not intended to limit the scope of this application. The term "and / or" as used in this application includes any and all combinations of one or more of the associated listed items.

[0051] Most agricultural drones on the market today use nozzles with fixed spacing to perform agricultural operations. For example... Figure 1 As shown, Figure 1 This is a schematic diagram of a commonly used UAV structure provided in an embodiment of this application. Figure 1 In this diagram, a coordinate system is established with gravity Y as the reference direction, and a side view of an agricultural drone in the XY plane is drawn. The commonly used drone has four rotors 1, which control the drone's flight state through rotation. It also has a storage tank 2 to hold the pesticide to be sprayed. A stirring device can be installed in the storage tank 2 to ensure the pesticide is evenly distributed during drone operation. The storage tank 2 and rotors 1 are mounted on a support frame 5, which also has four landing supports 4 to assist the drone in landing smoothly on the ground. A spraying device is fixed below the storage tank 2, including at least one set of nozzles 3. Each set of nozzles includes at least two nozzles, which are fixed to the spraying support 6 by mounting arms 7. A liquid guide tube 8 diverts the pesticide from the storage tank 2 into the nozzles 3.

[0052] However, due to the different growth stages and environments of different crops, this fixed-spacing nozzle layout may lead to poor operational efficiency, waste of pesticides, or inconvenience in use.

[0053] Meanwhile, the market demand for agricultural drones with adjustable nozzle spacing is constantly increasing. Therefore, spraying technology with adjustable nozzle spacing has become a research hotspot in recent years, enabling the spacing between nozzles to be automatically adjusted according to actual conditions, providing a more flexible, efficient, and controllable solution for agricultural operations.

[0054] The nozzle structure of agricultural drones typically consists of components such as nozzles, liquid pipes, and sealing rings. The nozzle's main function is to spray pesticides into the air, and its spraying effect and pesticide spraying quality are greatly influenced by the nozzle's design. Commonly used nozzles include fan-shaped nozzles, spherical nozzles, dual-flow nozzles, and four-flow nozzles, each with different spraying effects and coverage areas.

[0055] Fan-shaped sprinklers have a relatively simple structure and are suitable for applications with a large spraying area, such as farmland, orchards, and olive groves. Spherical sprinklers, on the other hand, can perform 360-degree rotating spraying and are suitable for irregularly shaped small fruit trees. Dual-flow and four-flow sprinklers can simultaneously spray a mixture of liquid and air, resulting in better spraying effects and pesticide utilization efficiency, but they are more expensive and difficult to maintain.

[0056] This application focuses on and provides a method for adjusting the spacing of centrifugal nozzles for agricultural drones. Centrifugal nozzles are widely used in agriculture, landscaping, firefighting, and other fields. The centrifugal nozzle mainly consists of a fixed block, a centrifugal rotation mechanism, and an atomizing disc. Its spraying principle utilizes centrifugal force to deliver liquid into the nozzle, creating a jet stream and producing a mist-like spray. Internally, the centrifugal rotation mechanism and the atomizing disc constitute the central shaft and rotating part, respectively. When the atomizing disc rotates, centrifugal force propels the liquid towards the nozzle, forming a mist-like spray.

[0057] The spraying effect of centrifugal sprinklers is affected by many factors, such as liquid flow rate, gravity, and the speed and angle of nozzle rotation. In agriculture, they can be used for crop spraying and fertilization, showing excellent results when spraying relatively viscous liquids. Centrifugal sprinklers are a highly practical type of sprinkler, offering stable spraying, adjustable nozzle angle and range, convenient maintenance, and wide applicability, thus improving spraying efficiency in agriculture and horticulture.

[0058] This application focuses on researching and providing a method for adjusting the spacing of centrifugal nozzles on agricultural drones. By collecting and analyzing relevant information such as crop, spraying agent, and drone parameters, performing real-time calculations, and outputting the results, intelligent adjustment and control of the nozzle spacing is achieved. This application not only improves the operational efficiency of agricultural drones, reduces pesticide waste and labor costs, but also provides new technical support for agricultural production through an environmentally friendly and efficient spraying method.

[0059] To better understand the solutions of the embodiments of this application, the following will first combine... Figure 2 A brief introduction to possible operating scenarios of the embodiments of this application is provided.

[0060] Figure 2 This is a schematic diagram of an agricultural drone spraying operation according to an embodiment of this application. As can be seen from the figure, during the drone's flight operation, the rotation of the rotor generates a downward wind field. Taking the gravity direction Y as a reference, the directions parallel to the ground and X are set.

[0061] It should be understood that the X direction includes all directions parallel to the ground and perpendicular to the direction of gravity Y. The accompanying drawings only schematically illustrate one X direction and do not constitute any limitation on the scope of protection of this application.

[0062] It should be understood that the droplets ejected by the centrifugal nozzle are 360-degree circumferences, and the attached diagram is only a two-dimensional planar schematic diagram and does not constitute any limitation on the scope of protection of this application.

[0063] The droplets sprayed by the centrifugal nozzle have an initial velocity V in the X direction. X Under the combined influence of an initial velocity in the X direction, the droplets' own gravity, and the wind force, they undergo parabolic motion. Let H be the spray height of the droplets, and R be the radius of the spray from the nozzle. f The distance between the two nozzles is N, and it is formed by... Figure 2 It can be clearly seen that, to ensure that agricultural drones spray without any blind spots and to guarantee uniform and comprehensive spraying, the nozzle spacing N should be less than or equal to twice the width R. f That is, N≤2R f .

[0064] Figure 3 This is a schematic flowchart illustrating a method for adjusting the spacing of centrifugal nozzles on an agricultural drone, as provided in an embodiment of this application. The following will be combined with... Figure 3 This application explains the method for confirming the centrifugal nozzle spacing.

[0065] When sprayed by a centrifugal nozzle, the liquid medicine is atomized by a high-speed rotating atomizing disc and ejected. The ejected droplets have an initial horizontal velocity V. XThe liquid is then carried towards the ground by the downward pressure of the rotor. The centrifugal atomizing disc rotates at high speed, causing the toothed protrusions on its outer edge to impact the liquid. Under this high-speed collision, the liquid is broken up and atomized. Here, the broken droplets are approximated as spheres, with the droplet size defined as d, the disc rotation speed as n, and the drug flow rate as f. The droplet size d is related to the disc rotation speed n and the drug flow rate f, and the relationship is as follows:

[0066] d=An+Bf+C (1)

[0067] Wherein, A, B, and C are coefficients to be determined. The rotational speed n of the atomizing disc and the flow rate f of the agent are known quantities that can be obtained through the machine settings of the drone. Before the actual operation of the drone, the specific values ​​of the coefficients to be determined A, B, and C can be determined through multiple experiments. The values ​​of the coefficients to be determined can be fitted based on the actual measured particle size d and the set rotational speed n and flow rate f. After multiple experiments and multiple fittings and averaging, a more accurate value of the coefficients to be determined A, B, and C can be obtained.

[0068] S201: Determine the initial velocity V of the droplets along the first direction based on the rotational speed n of the atomizing disc and the radius R of the toothed object. X .

[0069] The centrifugal atomizing disc rotates at high speed, causing the toothed edges on its outer edge to impact the liquid medication. This high-speed collision breaks the liquid into atomized droplets, which are then ejected with an initial horizontal velocity. This can be approximated as the initial velocity V of the ejected droplets. X The speed of movement is the same as that of the serrated edges of the atomizing disc. The following will combine... Figure 4 Regarding the initial velocity V of the droplets X The determination and calculation of are described.

[0070] Figure 4 This is a schematic diagram illustrating a method for generating mist droplets sprayed by an agricultural drone, as provided in an embodiment of this application. The radius of rotation of the toothed object on the atomizing disk is defined as R, and the rotational speed as n; where the unit of radius R is millimeters (mm), and the unit of rotational speed n is revolutions per minute (rpm). The rotation of the atomizing disk can be approximated as uniform circular motion. Based on the formula for calculating the linear velocity of uniform circular motion, the initial velocity V of the sprayed mist droplets can be obtained. X (i.e., the linear velocity of the toothed object on the atomizing disk) is:

[0071]

[0072] When the droplets are sprayed out from the toothed parts of the atomizing disc by rotation, they have an initial velocity V parallel to the ground. X Furthermore, the droplets are also affected by air resistance in the horizontal direction, thus their velocity in the X direction gradually decreases. The following will combine... Figure 5The trajectory and force conditions of the droplets were analyzed.

[0073] S202: Determine the air resistance coefficient μ of the droplets based on the droplet size d and the density ρ of the reagent.

[0074] Figure 5 This is a schematic diagram illustrating the force analysis of a droplet during spraying operations by an agricultural drone, provided in an embodiment of this application. Here, the droplet is approximated as a sphere with a diameter of d, and the droplet has an initial velocity V in the X direction when sprayed from the nozzle. X And it is subject to air resistance f in the opposite direction to the initial velocity. X The effect of gravity. In the gravitational direction Y, the droplets are affected by their own weight mg and the force f generated by the wind field generated by the drone rotor. Y Under the combined influence of the two forces, the droplets fall to the ground with an initial velocity of V in the Y direction. Y At the moment the droplets are just sprayed, i.e., t=0, the initial velocity V of the droplets in the Y direction is... Y =0.

[0075] Approximating the droplets as spheres, defining their diameter as d and the liquid density of the spray agent as ρ; then, under conditions of 25 degrees Celsius and standard atmospheric pressure, the air resistance coefficient μ of the droplets can be calculated as follows:

[0076]

[0077] S203: Obtain the first payload L of the agricultural drone at the first moment. Based on the first payload L, the number of drone rotors M, and the rotor diameter D, determine the first wind speed V of the downforce wind field generated by the rotors. S .

[0078] Define the velocity of the downdraft field of the drone rotor as V. S Given a drone with payload L, number of rotors M, and rotor diameter D, the wind speed V of the downforce wind field can be calculated under conditions of 25 degrees Celsius and standard atmospheric pressure. S for:

[0079]

[0080] Where g is the acceleration due to gravity.

[0081] The fog droplets undergo parabolic motion under the influence of the wind, with an initial velocity V in the horizontal X direction. X air resistance f X Under the influence of the wind, it slows down and undergoes deceleration; its initial velocity in the Y direction (direction of gravity) is 0, and it is affected by the wind force f. YUnder the influence of its own weight mg, the droplet accelerates; the entire droplet undergoes parabolic motion. If the air resistance coefficient is μ, then the air resistance f experienced by the droplet in the horizontal X direction is... X for:

[0082] f X =μmV X 2 (5)

[0083] In the gravitational direction Y, the initial velocity V of the droplet Y =0, under the influence of the downward-pressure wind field, the air resistance f experienced by the fog droplets is 0. Y for:

[0084] f Y =μm·(V S -V Y ) 2 (6)

[0085] Where m is the mass of the droplet.

[0086] In reality, the air resistance f experienced by fog droplets under the influence of a downward-pressure wind field is... Y The force is much greater than the droplet's own weight; therefore, to simplify the calculations, the effect of the droplet's own gravitational acceleration is ignored here. Thus, the parametric equations for the droplet's trajectory under the influence of the wind field can be obtained:

[0087]

[0088]

[0089] Combination Figure 2 It can be seen that R f H represents the width of the spray pattern and H represents the height at which the droplets fall.

[0090] S204: Obtain the first operating altitude H of the agricultural drone at the first moment, and based on the first operating altitude H and the first wind speed V of the downdraft wind field... S The air resistance coefficient μ is used to determine the first descent time t of the droplets.

[0091] Obtain the altitude parameter H of the UAV flight, substitute the obtained H value into formula (8), and combine it with the previous formulas (1) to (6) to calculate the motion time t of the droplets from spraying out to landing on the ground when the working altitude is H.

[0092] S205: Based on the first landing time t of the droplets and the initial velocity V of the droplets X The air resistance coefficient μ is used to determine the first distance R from which the droplets are sprayed along the first direction. f .

[0093] Substituting the calculated t value into equation (7), we can obtain the distance R that the droplets spread horizontally. f .

[0094] S206: Based on the first distance R of spraying in the first direction f Determine the first spacing N of the centrifugal nozzle of the agricultural drone at the first moment.

[0095] Combination Figure 2 It can be seen that, in order to ensure that the pesticide sprayed by the drone is uniform and without blind spots, the spacing N between the drone nozzles should be less than or equal to twice the droplet diffusion distance R. f That is, N≤2R f .

[0096] It should be understood that during drone operations, the drone can adjust its flight altitude according to factors such as the height of the crops and the planting density. The drone will also adjust the spacing of the centrifugal nozzles according to the flight altitude to ensure that the sprayed pesticide droplets are uniform and without dead angles.

[0097] It should be understood that this application can be applied to multi-nozzle drones. This application can be used to determine the distance between two nozzles in any horizontal direction. The specific scope of protection should be determined by the claims, and this application does not make any special limitations in this regard.

[0098] S207: Adjust the relative position between the centrifugal nozzles of the agricultural drone according to the first spacing N.

[0099] When the agricultural drone is at the second moment, its second payload and second operating altitude can also be acquired. Based on the second operating altitude, the second descent time of the droplets is determined. Based on the second descent time, the second distance the droplets are sprayed along the first direction and the second spacing between the centrifugal nozzles are determined. Based on the second spacing, the relative positions between the centrifugal nozzles of the agricultural drone are adjusted. The second moment refers to a time after the first moment, and includes moments when the payload and / or operating altitude of the agricultural drone change.

[0100] It should be understood that during the operation, the time interval between the first moment and the second moment can be automatically adjusted by a timed sampling method. The actual payload and operating height of the UAV at the second moment can be obtained by timed sampling, and the spacing between the centrifugal nozzles can be adjusted according to the actual operation data. Alternatively, sampling can be controlled by a terminal device, and the adjustment can be made according to the payload and operating height at the moment the terminal device sends the sampling command. This application does not make any special limitations in this regard, and the specific scope of protection is subject to the claims.

[0101] As a non-limiting embodiment, in one possible implementation, the atomizing disc rotates at a speed ranging from 1000 rpm to 16000 rpm, the radius R of the atomizing disc is 42 mm, and the drone has six rotors with a diameter of 1030 mm. The total payload of the drone is 120 kg. After experimental measurement and coefficient fitting, the values ​​of the undetermined coefficients A, B, and C can be determined. For example, after determining the values ​​of the undetermined coefficients A, B, and C, when the drone's flight altitude is 3 m, the swath width R can be calculated. f The value is 750mm. To avoid incomplete droplet coverage and missed spraying, the horizontal distance between the two nozzles can be set to twice the radius of radius R. f The value, that is, setting the nozzle spacing N, to 1500mm is appropriate.

[0102] The methods in the embodiments of this application, if implemented as software functional units and sold or used as independent products, can be stored in a computer-readable storage medium. Based on this understanding, the technical solution or part of the technical solution of this application can be embodied in the form of a software product. This computer software product is stored in a storage medium and includes several instructions to cause a computer device (which may be a personal computer, server, or network device, etc.) to execute all or part of the steps of the methods described in the various embodiments of this application. The storage medium includes at least: USB flash drives, portable hard drives, read-only memory (ROM), random access memory (RAM), magnetic disks, or optical disks, and other media capable of storing program code.

[0103] This application also provides an agricultural drone, which includes a rotor, a liquid storage tank, at least one set of centrifugal nozzles, and a controller. The rotor controls the drone's flight operations by rotation, the liquid storage tank stores the pesticide to be sprayed, and the centrifugal nozzles spray the pesticide. The controller is used to perform actions such as... Figures 2 to 5 The method described herein, wherein the controller is used to execute Figures 2 to 5 The calculation steps included in it.

[0104] It should be understood that the controller may also include sensors for acquiring the payload L of the UAV and the operating altitude H of the UAV, which is not specifically limited in this application.

[0105] It should be understood that the controller determines the spacing N between a set of centrifugal nozzles based on the calculation result of formula (7), and drives at least one set of centrifugal nozzles to adjust the spacing between the nozzles to be less than or equal to N. The specific scope of protection shall be subject to the claims, and this application does not make any special limitation in this regard.

[0106] The agricultural drone includes at least one set of centrifugal nozzles. The nozzle spacing between a set of centrifugal nozzles can be calculated using formulas (1) to (7). The agricultural drone may include multiple sets of centrifugal nozzles. The spacing between each set of centrifugal nozzles and the spacing between two centrifugal nozzles in a set of centrifugal nozzles can be determined by the above method. The controller adjusts the spacing between two nozzles in a set of centrifugal nozzles according to the calculated nozzle spacing N. The controller can also adjust the spacing between multiple sets of centrifugal nozzles according to the calculated nozzle spacing N. The specific scope of protection shall be subject to the claims. This application does not make any special limitation in this regard.

[0107] The above description is merely a specific embodiment of this application, but the scope of protection of this application is not limited thereto. Any person skilled in the art can easily conceive of various equivalent modifications or substitutions within the technical scope disclosed in this application, and these modifications or substitutions should all be covered within the scope of protection of this application. Therefore, the scope of protection of this application should be determined by the scope of the claims.

Claims

1. A method for adjusting and controlling the spacing of centrifugal nozzles on an agricultural drone, wherein the centrifugal nozzle includes an atomizing disc, the edge of which is provided with teeth, and the atomizing disc rotates to cause the teeth to impact the pesticide, thereby atomizing the pesticide into droplets and spraying it out from the centrifugal nozzle, characterized in that... include: The operation data of the agricultural drone is obtained, including the droplet size, the rotation speed of the atomizing disc, the radius of the tooth, the density of the agent, the number of rotors of the agricultural drone, and the diameter of the rotors; The initial velocity of the droplet along the first direction is determined based on the rotational speed of the atomizing disc and the radius of the tooth-like object, wherein the first direction is tangent to the atomizing disc and perpendicular to the direction of gravity; The air resistance coefficient of the droplets is determined based on the droplet size and the density of the agent. The first payload of the agricultural drone at the first moment is obtained, and the first wind speed of the downforce wind field generated by the rotor is determined based on the first payload, the number of rotors of the drone, and the diameter of the rotors. The first operating altitude of the agricultural drone at the first moment is obtained, and the first descent time of the fog droplets is determined based on the first operating altitude, the first wind speed, and the air resistance coefficient. Based on the first descent time, the initial velocity, and the air resistance coefficient, determine the first distance at which the droplets are sprayed along the first direction; Based on the first distance, determine the first spacing of the centrifugal nozzles at the first moment; Adjust the relative positions between the centrifugal nozzles of the agricultural drone according to the first spacing; in: Determining the first descent time of the fog droplets includes: in, H The first working height, This is the first wind speed. The air drag coefficient is obtained by acquiring the first operating altitude of the agricultural drone at the first moment. H Determine the first landing duration t ; Determining the first distance of the fog droplets includes: in, The first distance of the mist droplet. Let the initial velocity be... The air drag coefficient is... t The first landing duration, based on the first landing duration t The value determines the first distance The value; Determining the first spacing of the centrifugal nozzle includes: in, N For the first spacing, This is the first distance; Determining the droplet size includes: in, d The droplet size is [value missing]. n The rotational speed of the atomizing disc, f The flow rate of the atomizing disc, A , B , C These are undetermined coefficients; determining these undetermined coefficients includes measuring the droplet size. d Fit the values; Determining the air resistance coefficient of the mist droplets includes: in, The air drag coefficient is... d The droplet size is [value missing]. The density of the pharmaceutical agent; The first wind speed for determining the downforce generated by the rotor includes: in, This is the first wind speed. M The number of rotors, D The diameter of the rotor. L Let g be the first load amount, and g be the gravitational acceleration.

2. The method according to claim 1, characterized in that, Also includes: When the agricultural drone is at a second moment, acquire the second payload and the second operating altitude of the agricultural drone at the second moment; Based on the second operating height, determine the second descent time of the fog droplets; Based on the second descent time, determine the second distance the droplets are sprayed along the first direction and the second spacing between the centrifugal nozzles, and adjust the relative position between the centrifugal nozzles of the agricultural drone according to the second spacing; Wherein, the second moment is a moment after the first moment, and the second moment includes the moment when the payload of the agricultural drone and / or the operating altitude of the agricultural drone changes.

3. A computer-readable storage medium, characterized in that, Includes a computer program that, when run on a computer device, causes a processing unit in the computer device to perform the method as described in claim 1 or 2.

4. A chip, characterized in that, The chip includes a processor and a data interface. The processor reads instructions stored in the memory through the data interface to execute the method of claim 1 or 2.

5. A control system for adjusting the spacing of centrifugal nozzles of an agricultural drone, characterized in that, Installed in an agricultural drone, the agricultural drone also includes a rotor, a liquid storage tank, and at least one set of centrifugal nozzles, wherein... The rotor controls the flight of the agricultural drone by rotation, the liquid storage tank is used to store the pesticide to be sprayed, the centrifugal nozzle is used to spray the pesticide, and the control system is used to execute the method as described in claim 1 or 2.

6. An agricultural unmanned aerial vehicle, characterized in that, include: The components include a rotor, a liquid storage tank, at least one set of centrifugal nozzles, and a controller. The rotor controls the flight of the agricultural drone by rotation, the liquid storage tank is used to store the agent to be sprayed, the centrifugal nozzle is used to spray the agent, and the controller is used to execute the method as described in claim 1 or 2.

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