Controlling the flow rate of a spray liquid exiting a spray nozzle on a spray boom, particularly in response to changes in direction and / or speed of a sprayer

Abstract

The present invention relates to an electronic system (100) for managing the flow rate (di) of a spray liquid exiting a spray nozzle (Bi) on a spray boom (210) equipping a spraying machine (200), said spray boom (210) comprising a plurality of variable-flow spray nozzles (Bi), said system (100) comprising: - a collection module (10) configured to collect displacement data (DATA_vi) including information relating to the relative velocity (vi) of said at least one spray nozzle (Bi) at a given time t; and - a processing unit (20) configured to determine a flow rate (di) of the liquid to be sprayed at time t+1 by said at least one spray nozzle (Bi) as a function of the relative velocity (vi) of said at least one nozzle (Bi) and a determined dose (D) of spray liquid to be sprayed at time t+1. Abstract figure: Figure 1

Description

Title of the invention: Management of the flow rate of a spray liquid at the outlet of a spray nozzle on a spray boom, in particular as a function of a change in direction and / or speed of a sprayer Technical field

[0001] The present invention relates to the field of electronics and more particularly to the field of systems for regulating the flow rate of a spray liquid at the outlet of a spray nozzle on a spray boom of a spraying machine or sprayer of the spreading vehicle or other type.

[0002] One of the objects of the present invention aims to propose a solution for managing the flow rate of a liquid for a sprayer in order to spray a spray liquid (for example a phytosanitary liquid) in a localized manner on a surface (for example an agricultural surface, leaf surface, roof, railway, etc.) according to a determined or variable spray dose, taking into consideration in particular the relative speed of the nozzle, for example in particular during a circular movement, a change of direction or even a turn thereof.

[0003] One of the other objects of the present invention relates to an agricultural machine of the spreading vehicle type comprising a spray boom equipped with a plurality of spray nozzles and a system for managing the flow rate at the outlet of each nozzle.

[0004] The present invention will find, in a non-exclusive manner, advantageous applications in the agricultural, arboricultural and / or viticultural fields, in particular by coupling it to a sprayer calculator in order to regulate the flow rate in the circuit of the spreading booms and to maintain the pressure constant at the outlet of each nozzle.

[0005] The present invention will find other advantageous applications in other fields such as, for example, weed control for roads, spreading for road works (public works field) and / or railways (railway field). Prior art

[0006] Sprayers are known in the agricultural and wine-growing fields.

[0007] Sprayers are conventionally intended to spray products on crops in liquid form.

[0008] We also talk about inputs.

[0009] Such sprayers are for example used to apply phytosanitary liquids and / or foliar fertilizers to crops for weed control or even for treat crops against certain diseases and / or control certain insects (insects, mites, etc.) which are likely to harm the harvest.

[0010] A sprayer generally comprises a storage tank or vessel containing the liquid to be sprayed; this tank is connected to a circuit equipped with a high-pressure pump (or equivalent) and one or more spray nozzles.

[0011] Such sprayers can be fitted to a motorized vehicle of the agricultural type such as, for example, a tractor, self-propelled vehicle or even an aircraft (autonomous or not).

[0012] We are talking about spreading vehicles.

[0013] To meet the specificities of the plants to be treated and environmental regulations, conventional nozzles are now replaced by electronic nozzles with variable flow.

[0014] Thus, sprayers are now known which integrate electronic control systems comprising a central computer connected to the spray bar and capable of independently controlling the outputs of each nozzle.

[0015] In the field of agriculture, certain spreading vehicles include a sprayer system consisting of a boom articulated at the rear (or front) of the vehicle.

[0016] Such a boom can for example be several tens of meters wide and the spray nozzles can be fixed on the boom for example approximately every fifty centimeters, or even every twenty-five centimeters.

[0017] Obviously, it will be understood that the above dimensions and spacings are provided here for purely indicative purposes and are in no way limiting or restrictive.

[0018] Thus, still according to this example, a spreading vehicle which is equipped with a boom forty-eight meters wide with a nozzle fixed every fifty centimeters will have a central computer which must be capable of controlling in real time and independently the ninety-six nozzles fixed on the boom; obviously, these dimensions can be modified and other boom widths and other spacing distances between the nozzles can be provided.

[0019] In theory, such nozzle control (real time and independent) makes it possible to carry out localized spraying to spray the field in a piecemeal manner, i.e. on short sections of the field plot; it is therefore understood that the control of these nozzles for localized spraying may require simultaneous actuation of all the nozzles as well as actuation of a single nozzle. This is also referred to as nozzle-to-nozzle control.

[0020] This nozzle-to-nozzle control therefore presents numerous theoretical advantages: it makes it possible to reduce spraying costs and associated pollution by optimizing the use of the sprayed liquid.

[0021] Such localized spraying systems further allow for improved spraying accuracy by correctly spraying sections of the field according to actual needs.

[0022] On the other hand, the Applicant observed that, from a practical point of view, spraying nozzle by nozzle remains difficult to implement.

[0023] With current sprayers, it is in fact very difficult to ensure this localized spraying in a fully satisfactory manner because the configuration of the sprayer's water circuit does not allow for a stable spray flow rate at the nozzle outlet.

[0024] Transition times are indeed observed when controlling a single nozzle.

[0025] These transition times are caused by an opening of the nozzle which results in a significant pressure drop which does not allow for optimized spraying.

[0026] In “localized spraying” mode, the Applicant found that it was important to maintain a constant pressure at the nozzle outlet without transition time so that the spraying is optimal. However, as explained above, a loss of pressure is systematically observed in current circuits, which involves a transition time to reach the desired flow rate at the nozzle outlet.

[0027] The only prior art solutions that claim to implement a "localized spraying" uses nozzles and / or multi-nozzles controlled by section and not individually (i.e. nozzle to nozzle).

[0028] Such solutions are found, for example, in documents FR2964577A1 and EP3338546A1.

[0029] The Applicant also observes very high latency times for the solutions of these documents FR2964577A1 and EP3338546A1.

[0030] It is also observed that none of the existing solutions take into consideration the trajectory of said vehicle. Indeed, certain agricultural surfaces require going around an obstacle and / or may be circular in shape. The trajectory of the vehicle is therefore not necessarily rectilinear.

[0031] However, in a bend, the relative speed of one end of the ramp is very different from the relative speed of another end of the ramp.

[0032] The Applicant further observes that these speeds

[0033] With current solutions, spraying in a bend remains the same and does not take into account the trajectory and speed of the vehicle which are constantly changing.

[0034] The Applicant submits that, for these reasons, the sprayers which are known until now and which comprise a control module capable of controlling nozzle sections are not efficient and do not allow precise and localized spraying to provide the appropriate dose of spray liquid. Summary of the invention

[0035] The present invention aims to improve the situation described above.

[0036] The present invention aims in particular to remedy at least one of the various technical problems mentioned above by proposing an optimal nozzle-to-nozzle spraying solution that can be adapted to the existing circuit.

[0037] The subject of the present invention relates, according to a first aspect, to a method for managing a flow rate of a spray liquid at the outlet of at least one spray nozzle on a spray boom equipping a spraying machine of the type, for example, a spreading vehicle moving over a surface to be treated, the spray boom comprising a plurality of variable flow rate spray nozzles distributed along the boom.

[0038] Advantageously, the method according to the present invention comprises the following steps: - a collection of movement data comprising information relating to a relative speed of the at least one spray nozzle at a determined instant t; and - a determination of the flow rate of the liquid to be sprayed at time t+1 by the at least one spray nozzle as a function of the relative speed of the at least one nozzle at time t and a determined dose of spray liquid to be sprayed at time t+1.

[0039] Thus, by taking into consideration the relative speed of the at least one nozzle, it becomes possible to apply in real time the correct flow rate at the outlet of each nozzle to apply the expected dose of spray liquid to the surface to be treated.

[0040] This consideration of the relative speed of the nozzle makes it possible to avoid overdosing and / or underdosing, in particular when a machine of the spreading vehicle type makes a turn and / or when the vehicle treats a circular surface and / or when the vehicle makes a U-turn (cutting off the spraying in real time).

[0041] Thanks to the above technical characteristics, and in particular taking into consideration the relative speed of each nozzle, a spraying solution is available which ensures nozzle-to-nozzle spraying with a controlled flow rate which is a function of the target dose to be sprayed.

[0042] Taking this new parameter into consideration ensures localized spraying (nozzle to nozzle) with an adapted flow rate at the outlet of each nozzle for precise dosage.

[0043] Advantageously, the method according to the present invention comprises a generation of a control signal; such a signal preferably comprises the flow rate of the liquid to be sprayed at time t+1 and a transmission of the control signal to the at least one spray nozzle.

[0044] Advantageously, the relative speed of the at least one nozzle is collected via a geolocation beacon of the GPS type, for example.

[0045] Advantageously, the collection step comprises a measurement of an angular speed of the at least one nozzle, for example using a gyroscope placed on the boom or on the sprayer.

[0046] Advantageously, the collection step comprises a measurement of a speed of movement of the vehicle at the instant, for example by an accelerometer placed on the vehicle or the ramp.

[0047] Alternatively, this travel speed can also be provided directly by the vehicle (for example by an intelligent system of said vehicle or equivalent).

[0048] Advantageously, it can be envisaged that, during the determination step, the relative speed of the nozzle is calculated as a function of the speed of movement of the vehicle.

[0049] Advantageously, it can be envisaged that, during the determination step, the relative speed of the nozzle is further calculated as a function of a relative position of the nozzle on the ramp.

[0050] Taking into account this relative position of the nozzle on the boom is desirable, particularly during a turn. Indeed, during such a turn, the internal part of the boom moves at a lower speed than that of the external part of the boom.

[0051] Each nozzle on the ramp therefore has a different relative speed depending on its relative position on the ramp.

[0052] Advantageously, it may be envisaged that, during the determination step, the relative speed of the nozzle is further calculated as a function of a steering angle of the vehicle, for example using an angular sensor between the spraying machine and the boom). This alternative makes it possible to refine the determination of the relative speed of the nozzle during a turn according to a determined steering angle. Such a steering angle in fact makes it possible to know the radius of curvature of the turn made which makes it possible to determine the relative speed of each nozzle in the turn when the relative position of the latter in the boom is known.

[0053] Advantageously, it is possible to envisage the presence of a sensor configured to determine the possible whipping phenomena of the boom at the exit of a bend or when the boom collides with an obstacle. Indeed, it is noted that these whipping phenomena can lead to approximations in the spraying.

[0054] The presence of this sensor makes it possible to overcome these problems.

[0055] Advantageously, the determined dose of spray liquid to be sprayed at time t+1 is constant.

[0056] Advantageously, the determined dose of spray liquid to be sprayed at time t+1 is modulated by a map of the surface to be treated. In other words, the map of the surface to be treated is known and, in this variant, it is possible to determine in advance the dose to be sprayed on each portion of the surface to be treated. In this variant, geolocation of the nozzle is thus provided to determine its relative position with respect to the map of the surface to be treated.

[0057] Advantageously, the determined dose of spray liquid to be sprayed at time t+1 is determined at time t by capturing, using a camera, an image comprising the surface to be treated and processing said image. It is understood here that the processing of said image is carried out by image processing algorithms dedicated to the recognition of characteristics of the plant to be treated (nature, type, shape, volume of the leaf surface, etc.) and / or by algorithms of the Machine Learning type.

[0058] According to a second aspect, the subject of the present invention relates to a computer program which comprises instructions adapted for the execution of the steps of the method according to the first aspect of the invention, in particular when the computer program is executed by at least one processor.

[0059] Such a computer program may use any programming language, and be in the form of source code, object code, or intermediate code between source code and object code, such as in a partially compiled form, or in any other desirable form.

[0060] According to a third aspect, the subject matter of the present invention relates to a computer-readable recording medium on which is recorded a computer program comprising instructions for executing the steps of the method according to the first aspect of the invention.

[0061] On the one hand, the recording medium may be any entity or device capable of storing the program. For example, the medium may comprise a storage means, such as a ROM memory, a CD-ROM or a microelectronic circuit type ROM memory, or even a magnetic recording means or a hard disk.

[0062] Furthermore, this recording medium may also be a transmissible medium such as an electrical or optical signal, such a signal being able to be conveyed via an electrical or optical cable, by conventional or hertzian radio or by self-directed laser beam or by other means. The computer program according to the invention may in particular be downloaded from an Internet-type network.

[0063] Alternatively, the recording medium may be an integrated circuit in which the computer program is incorporated, the integrated circuit being adapted to perform or to be used in performing the method in question.

[0064] The subject of the present invention relates, according to a fourth aspect, to an electronic system for managing a flow rate of a spraying liquid at the outlet of at least one spray nozzle on a spray boom equipping a spraying machine of the type, for example, a spreading vehicle, the spray boom comprising a plurality of variable flow rate spray nozzles distributed along the boom.

[0065] According to the present invention, the system advantageously comprises: - a collection module configured to collect movement data comprising information relating to the relative speed of the at least one spray nozzle at a determined time t; and - a processing unit configured to determine a flow rate of the liquid to be sprayed at time t+1 by the at least one spray nozzle as a function of the relative speed of the at least one nozzle at time t and a determined dose of spray liquid to be sprayed.

[0066] Advantageously, the system according to the present invention comprises means configured for implementing the steps of the method as described above according to the first aspect of the present invention.

[0067] Advantageously, each spray nozzle of the boom is a variable flow nozzle or a pulsating nozzle.

[0068] Preferably, each variable flow rate spray nozzle is capable of being electrically controlled by a control unit using PWM technology capable of varying the flow rate of each nozzle by modulating the opening duration during an opening / closing cycle of the nozzle.

[0069] Such PWM technology for “Pulse Width Modulation” (or pulse width modulation) is based on the principle of varying the flow rate of the nozzles by modulating the duration of the nozzle opening cycle.

[0070] Preferably, the variable flow nozzles have an opening / closing frequency of 10 to 100 Hertz.

[0071] In other words, it is understood here that each nozzle is capable of opening and closing 10 to 100 times per second. The modulation of the flow rate of the nozzle is therefore carried out here by varying the duration of opening of the nozzle within an opening / closing cycle.

[0072] The subject of the present invention relates, according to a sixth aspect, to a spraying machine of the type, for example, a spreading vehicle comprising: - a spray bar equipped with a plurality of variable flow spray nozzles distributed along said bar, each spray nozzle being capable of spraying said spray liquid; and - a spraying system as described above according to the fifth aspect of the present invention.

[0073] Preferably, said spraying device is of the motorized vehicle type, autonomous or not.

[0074] Preferably, said spraying device further comprises: - a tank containing a liquid to be sprayed (for example a phytosanitary liquid); and / or - a spray circuit connecting the tank and the boom in a loop; and / or - a control unit capable of controlling each nozzle independently of one another for nozzle-to-nozzle spraying; and / or - a pump.

[0075] Preferably, said pump is located downstream of the circuit on the inlet loop between the reservoir and the spray bar, the pump being capable of injecting the liquid into the spray circuit at a determined flow rate.

[0076] Preferably, the pressure in the spray circuit is kept constant at 3 bars.

[0077] Thus, by its various functional and structural technical characteristics described above, an efficient nozzle-to-nozzle spraying system is provided which ensures spraying with an adapted flow rate at the nozzle outlet to provide the correct dose on the surface to be treated and avoid overdosing or underdosing; it will also be noted that such a system can be adapted to existing circuits by making a minimum of modifications. Description of figures

[0078] Other characteristics and advantages of the present invention will emerge from the description below, with reference to the appended figures which illustrate an exemplary embodiment thereof without any limiting character and in which:

[0079] [Fig.l]

[0080] [Fig.l] represents a schematic top view of a spraying machine of the spreading vehicle type comprising a nozzle flow management system according to an exemplary embodiment of the present invention when said finally makes a turn while spraying a spraying liquid;

[0081] [Fig.2]

[0082] [Fig.2] represents a flowchart of the method for managing the flow rate of the nozzles of a spray boom of a spraying machine according to [Fig.l]; and

[0083] [Fig.3]

[0084] [Fig. 3] represents a schematic view of a nozzle flow management system according to an exemplary embodiment of the present invention. Detailed description

Claims

[0085] A system for managing the flow rate of nozzles on a boom for nozzle-to-nozzle spraying according to an exemplary embodiment of the present invention as well as the associated vehicle will now be described in the following with reference jointly to Figures 1 to 3. [0086] The exemplary embodiment described here will relate more specifically to a spreading vehicle 200 as illustrated in [Fig.l]. It will be understood that this is one exemplary embodiment among others possible and that the present invention may relate to any type of sprayer. [0087] In the exemplary embodiment of [Fig.l], the spreading vehicle 200 comprises a tractor 202 towing a trailer 201 on which a spraying system is conventionally mounted. [0088] It is understood here that this is one example among others possible. Indeed, the present invention is not limited to this exemplary embodiment and the spraying system can also be trailed or carried according to other variants. [0089] In the example described, the spraying system comprising: - a tank (not shown here) containing a liquid to be sprayed such as, for example, a phytosanitary liquid; and - a spray bar 210 having at least one section with a plurality of spray nozzles Bi (i here being a positive integer between 1 and N, N being equal to 36 in this example). [0090] In this example, the spray bar 210 more particularly comprises thirty-six spray nozzles B1 to B36 distributed every fifty centimeters over a total length of eighteen meters. [0091] In this example, for correct operation of the spraying, a circuit (not shown here) is provided which connects the reservoir to the boom 210 in a loop. It is understood in this example that the reservoir is connected to the inlet of the boom 210 by an inlet loop of the circuit and that the outlet of the boom is connected to the reservoir by a return loop. [0092] A pump (not shown here) and a control valve (not shown here) are also provided in a known manner. [0093] In this example, the pump is located downstream of the circuit (i.e. on the arrival loop of the circuit) between the reservoir and the spray bar 210. Here, the pump is configured to inject the liquid into the spray circuit at a determined variable flow rate. [0094] The control valve is located upstream of the circuit (i.e. on the return loop of the circuit) between the spray bar 210 and the tank. [0095] In the example described here, the Bi nozzles are preferably variable flow and are of the PWM type (ON / OFF type nozzles could also be provided in certain variants). [0096] In this example, the nozzles Bi are electrically controlled by the control unit 30 to actuate and trigger the opening of each nozzle during an opening / closing cycle thereof. [0097] In this example, an opening / closing frequency of 10 to 100 Hertz is provided for each nozzle. [0098] In this example, the implementation of a control unit 30 is further provided. [0099] Such a control unit 30 is configured to control each of the independent Bi nozzles depending on each other. [0100] Such a control unit 30 is particularly appreciated in the field of spreading and spraying; it allows for localized spraying. It can also allow for localized weeding depending on the use case. [0101] By controlling the nozzles independently of each other, it is possible to spray portions of plots and therefore reduce the spraying depending on the surface area to be treated, for example. [0102] This localized spraying responds to numerous ecological challenges by making it possible to reduce, or at least optimize, the use of inputs on agricultural land. [0103] As explained in the preamble, current solutions do not take into consideration the variations in trajectories of the spreading vehicle 200. [0104] However, it is noted that, taking into account the span of a boom 210 (eighteen meters in this example), the relative speed of one end 210a of the boom 210 is very different from the relative speed of the other end 210b of the boom 210 when the vehicle 200 makes a turn, for example to treat a circular agricultural area; this is not the case when the vehicle has a rectilinear trajectory. [0105] This assumes that the outside turn is longer than the rope turn: the larger the radius of curvature of the initiated turn, the longer the outside turn is compared to the rope turn. [0106] Thus, as illustrated in the example of [Fig.l], it can be seen that, during a turn, the relative speed vl of the nozzle BI located at the internal end 210a of the ramp is much lower than the relative speed v2 of the nozzle B2 located at the external end 210b of the ramp 210. [0107] For example, when a spreading vehicle 200 moving at a speed of four kilometers per hour and equipped with an eighteen-meter spray boom 210 makes a turn with a radius of curvature of nine meters, we can observe: - a relative speed of the internal end 210a of the ramp 210 (here the rope) equal to one hundred and ten centimeters per hour; and