Spray pattern monitoring system

With the use of electromagnetic radiation sources, such as lasers emitting light, and corresponding detectors, spray patterns from spray nozzle assemblies can be sampled and compared to one or more calibration patterns to determine if nozzles of spray nozzle assemblies are worn out. A unique calibration pattern could be used to compare for each spray nozzle assembly, and/or a single calibration pattern could be used to compare for multiple spray assemblies. In one aspect, detectors can be arranged near sources to detect electromagnetic radiation reflected by spray patterns. In another aspect, detectors can be arranged opposite of sources to detect electromagnetic radiation transmitted through a spray pattern.

FIELD OF THE INVENTION

The present invention relates generally to agricultural sprayers, and in particular, to spray systems for agricultural sprayers in which electromagnetic radiation sources and detectors are used to produce detection patterns corresponding to spray patterns of spray nozzle assemblies for comparing to calibration patterns to determine when such spray nozzle assemblies are worn out.

BACKGROUND OF THE INVENTION

Field sprayers, as known in the art, are typically attached to, or towed by, an agricultural implement such as a tractor or other vehicle, or are a dedicated self-propelled sprayer vehicle, Such sprayers generally include a fluid holding tank supported by a frame. The fluid holding tank typically stores a crop protection fluid, such as pesticides or liquid fertilizer, which often consists of a carrier fluid (such as water) mixed with a chemical at a predetermined concentration. The fluid holding tank, in turn, is fluidly coupled to a series of spray nozzles spaced apart from one another along booms extending outwardly from the frame. Accordingly, the crop protection fluid may be dispensed through the spray nozzles onto the farm field, preferably in an even distribution spray pattern, so that the fluid is applied consistently across the farm field.

In some situations, the outlet of spray nozzles (orifices) may become worn out, thereby causing an undesirable increase in fluid flow (or undesirable loss of pressure at the same fluid flow) and/or irregular spray patterns at the spray nozzle outlet. This may result in a wasteful distribution of excess fluid and/or an inefficient distribution of fluid on the agricultural field. Consequently, what is needed is an efficient way to accurately determine when a particular spray nozzle has worn out and therefore requires replacement.

SUMMARY OF THE INVENTION

With the use of electromagnetic radiation sources, such as lasers emitting light, and corresponding detectors, spray patterns from spray nozzle assemblies can be sampled and compared to one or more calibration patterns to determine if nozzles of spray nozzle assemblies are worn out. A unique calibration pattern could be used to compare for each spray nozzle assembly, and/or a single calibration pattern could be used to compare for multiple spray assemblies. In one aspect, detectors can be arranged near sources to detect electromagnetic radiation reflected by spray patterns. In another aspect, detectors can be arranged opposite of sources to detect electromagnetic radiation transmitted through a spray pattern.

In one aspect, the invention can provide a system for monitoring the spray pattern of nozzles using a low cost laser beam and receiver. An ideal spray pattern can be modelled and/or a new nozzle's spray pattern can be captured when first installed on a boom with the use of a laser beam and target receiver. Acceptable limits to changes in the spray pattern can be established and then in real time the nozzle spray pattern can be monitored with the system. When a nozzle goes out of limits, a flag can be thrown. Aspects of this invention can be applied to autonomous sprayers in which an on-board monitoring system is used.

Specifically then, one aspect of the present invention provides a spray system including: a boom supporting a spray nozzle assembly having an outlet for discharging fluid in a spray pattern onto an agricultural field; an electromagnetic radiation source positioned near the outlet, the source being configured to direct a beam of electromagnetic radiation through the spray pattern; an electromagnetic radiation detector positioned near the outlet, the detector being configured to detect electromagnetic radiation transmitted through the spray pattern or reflected by the spray pattern to produce a detection pattern; a data structure holding a calibration pattern providing a target for electromagnetic radiation transmitted through the spray pattern or reflected by the spray pattern; and a controller in communication with the detector and the data structure, the controller being configured to receive the detection pattern and compare the detection pattern to the calibration pattern to determine an error for the spray nozzle assembly.

Another aspect of the present invention provides a method for determining a worn spray nozzle assembly including: discharging fluid in a spray pattern onto an agricultural field from an outlet of a spray nozzle assembly supported by a boom; directing a beam of electromagnetic radiation from an electromagnetic radiation source positioned near the outlet through the spray pattern; detecting electromagnetic radiation transmitted through the spray pattern or reflected by the spray pattern at an electromagnetic radiation detector positioned near the outlet to produce a detection pattern; and comparing the detection pattern to a calibration pattern providing a target for electromagnetic radiation transmitted through the spray pattern or reflected by the spray pattern to determine an error for the spray nozzle assembly.

Another aspect of the present invention provides a self-propelled sprayer including: an operator cab supported by a chassis; a wing boom supported by the chassis, the wing boom including multiple spray nozzle assemblies, each spray nozzle assembly having an outlet for discharging fluid in a spray pattern onto an agricultural field; multiple electromagnetic radiation sources, each source being positioned near an outlet, each source being configured to direct a beam of electromagnetic radiation through a spray pattern discharged from the outlet; multiple electromagnetic detectors, each detector being positioned near an outlet, each detector being configured to detect electromagnetic radiation transmitted through a spray pattern or reflected by a spray pattern discharged from the outlet to produce a detection pattern; a data structure holding multiple calibration patterns providing targets for electromagnetic radiation transmitted through the spray patterns or reflected by the spray patterns; and a controller in communication with the detectors and the data structure, the controller being configured to receive detection patterns and compare the detection patterns to the calibration patterns to determine an error for each spray nozzle assembly.

DETAILED DESCRIPTION OF THE DRAWINGS

Referring generally to the drawings, and more particularly toFIG. 1, an exemplar agricultural product application system, which in the illustrated embodiment is a field spraying system10(a tractor with a three point mounted sprayer attached), is shown in accordance with the present invention. The field spraying system10can comprise a self-propelled sprayer12having an operator cab14and a primary fluid tank16supported by a chassis18. A rear end20of the chassis18may support a wing boom22(or multiple wing booms) to which one or more secondary fluid tanks, which could be provided as illustrated by reference numeral24, may be supported. The wing boom22also supports a series of spray nozzle assemblies26for spraying an area of a field. The chassis18is supported by a set of wheels28, and the wing boom22, depending on size, can be additionally supported by a set of smaller wheels (not shown).

Primary distribution lines30are flow coupled between the primary fluid tank16and the spray nozzle assemblies26. The primary fluid tank16may typically store a carrier fluid such as water. The primary distribution lines30may provide flow of the carrier fluid to the spray nozzle assemblies26directly or indirectly, such as via one or more charge pumps, accumulators, control valves, pressure relief valves, manifolds and/or supplemental distribution lines in the path as understood in the art for effecting various flow rates, pressures and control for sprayer configurations.

Secondary distribution lines, which could be provided as illustrated by reference numeral32, may be flow coupled between one or more of the secondary fluid tanks24and the spray nozzle assemblies26. The secondary fluid tanks24may typically store a chemical fluid, such as a liquid fertilizer, pesticide, herbicide, or the like. The secondary distribution lines32may provide flow of the chemical fluid to the spray nozzle assemblies26directly or indirectly, such as via one or more charge pumps, accumulators, control valves, pressure relief valves, headers, manifolds and/or supplemental distribution lines in the path as understood in the art for effecting various flow rates, pressures and control for sprayer configurations. Accordingly, the carrier fluid and the chemical fluid may be stored in different tanks and subsequently mixed at each of the spray nozzle assemblies26thereby providing improved distribution in the field. The secondary fluid tanks24are typically smaller than the primary fluid tank16.

Referring now toFIG. 2, a pictorial view of an exemplar spray nozzle assembly26with a pattern detection system27is provided in accordance with the present invention. In one aspect, the spray nozzle assembly26may generally include a nozzle body40, coupled in turn to a mixing body42, coupled in turn to a control valve44. The nozzle body40could be thread coupled to the mixing body42, and the mixing body42could be thread coupled to the control valve44, although other temporary or permanent coupling techniques could be used, such as pressure fittings and/or adhesive agents.

The nozzle body40includes a nozzle outlet46(exposing an orifice) for spraying a mixed fluid which will typically consist of a carrier fluid (such as water) mixed with a chemical fluid at some concentration. The nozzle body40may also include a nozzle body inlet48for receiving the carrier fluid. The carrier fluid may come from the primary fluid tank16via the primary distribution lines30.

The mixing body42may include a mixing body inlet50for receiving the chemical fluid (such as a liquid fertilizer, pesticide, herbicide, or the like). The chemical fluid may come from either of the secondary fluid tanks24via the secondary distribution lines32. Within the mixing body42, a flow control mechanism may provide a mixing chamber43(seeFIG. 3) for mixing the carrier fluid with the chemical fluid in the nozzle to provide the mixed fluid.

The control valve44may operate to stop the mixed fluid from flowing to the nozzle outlet46, or to allow the mixed fluid to flow to the nozzle outlet46for spraying. The control valve44could be a passive check valve, as shown inFIG. 2, in which the mixed fluid is mechanically stopped from flowing if there is insufficient pressure applied by the mixed fluid against a valve mechanism, or the mixed fluid is allowed to flow if there is a build-up of sufficient pressure of the mixed fluid against the valve mechanism. Alternatively, the control valve44could be an actively controlled solenoid valve, as shown inFIG. 3by reference numeral74, in which the mixed fluid is stopped from flowing or allowed to flow depending on a control signal provided to a solenoid which actuates a valve. Accordingly, the control valve44may serve to prevent undesirable leaking of the mixed fluid. Also, the control valve44may be operator or computer controlled in the field.

Still referring toFIG. 2, the pattern detection system27can include an electromagnetic radiation source52and an electromagnetic radiation detector54. The source52and the detector54can each be positioned proximal to the nozzle outlet46. Accordingly, the source52can be configured to direct a beam59of electromagnetic radiation through a spray pattern discharged by the spray nozzle assembly26at the nozzle outlet46. In addition, the detector54can be configured to detect electromagnetic radiation transmitted through the spray pattern, such as when the source52and the detector54are arranged on opposing sides of a spray pattern as shown inFIGS. 2 and 4A, or in other aspects, detect electromagnetic radiation reflected by the spray pattern, such as when the source52and the detector54are arranged proximal to one another as shown inFIG. 4B. The detector54, in turn, can produce a detection pattern or signature from the detected electromagnetic radiation corresponding to a sampling of the spray nozzle assembly26at a particular time. In one aspect, the source52could include a laser55, such as a Helium-Neon laser (HeNe) able to operate at a number of different electromagnetic wavelengths, with a collimating lens56operable to focus light emitted by the laser through the spray pattern. The detector54could include a Fourier lens57or other optics operable to direct light from the spray pattern toward a photodiode array58.

Referring now toFIG. 3, a schematic view of a nozzle wear out detection system, shown as nozzle flow detection system100, is provided in accordance with the present invention. A first distribution path102may be provided for distributing a first fluid, which may be a carrier fluid stored in the primary fluid tank16. The first distribution path102may receive the carrier fluid via the primary distribution line30, and may include a first electronically controlled valve104(identified as “V1”), which may be a solenoid valve operating in a manner similar to the solenoid control valves described above with respect toFIG. 3, for metering the carrier fluid to a mixing chamber of a spray nozzle assembly26.

A second distribution path106may be provided for distributing a second fluid, which may be the chemical fluid stored in the secondary fluid tank24, The second distribution path106may receive the chemical fluid via the secondary distribution line32. The second distribution path106preferably distributes the chemical fluid at a higher pressure than the first distribution path102distributing the carrier fluid. The second distribution path106may include a metering system which may consist of a second electronically controlled valve108(identified as “V2”).

A controller110may be configured, among other things, to control the first and second electronically controlled valves104and108, respectively. The controller110may be a microprocessor, a microcontroller or other programmable logic element as known the art.

The first and second distribution paths102and106, in turn, may be coupled to a spray nozzle assembly26(at the mixing chamber43), such that the chemical fluid and the carrier fluid may be mixed to produce the mixed fluid. The spray nozzle assembly26may include a third electronically controlled valve74(identified as “V3”) for controlling flow of the mixed fluid between the mixing chamber43and the nozzle outlet46, and the controller110may be further configured to control the third electronically controlled valve74.

In an alternative arrangement, the chemical fluid and the carrier fluid may be mixed earlier upstream, including being premixed in combined bulk tank, with a single distribution path provided to the spray nozzle assembly as understood the art (instead of separate chemical and carrier tanks with separate distribution paths). Also, although only a single metering system and spray nozzle assembly26is shown inFIG. 3for ease of understanding, it will be appreciated that the nozzle flow detection system100will typically include numerous spray nozzle assemblies26, and perhaps numerous metering systems, as provided in the field spraying system10shown inFIG. 1.

Still referring toFIG. 3, the pattern detection system27can be positioned proximal to the nozzle outlet46of the spray nozzle assembly26, such as within a few inches. The pattern detection system27could be mounted to the spray nozzle assembly26and/or the wing boom22.

With additional reference toFIG. 4A, in one aspect, the detector54can be configured to detect electromagnetic radiation transmitted through a spray pattern112. In such an arrangement, the source52and the detector54could be arranged on opposing sides of the spray pattern112with a beam59transmitting directly through the spray pattern112from the source52to the detector54. The detector54could then detect the beam59in a first state120, with particular intensities at varying wavelengths, corresponding to a known good state, such as when substantially new or initially deployed, as shown inFIG. 5Awith consistent dashed lines denoting a desirable spray pattern112′. Then at a later time, upon the nozzle outlet46becoming worn, the detector54could detect the beam59in a second state122, with different intensities at varying wavelengths, corresponding to a bad state which sufficiently deviates from the first state120(good state) by at least a predetermined threshold, as shown inFIG. 5Bwith solid lines denoting heavy streams in an undesirable spray pattern112″.

Similarly, with additional reference toFIG. 4B, in another aspect, the detector54can be configured to detect a reflection114of electromagnetic radiation transmitted through a spray pattern112. In such an arrangement, the source52and the detector54could be arranged proximal to one another, on a same side of the spray pattern112, with a beam59transmitting into the spray pattern112from the source52causing the reflection114to return to the detector54. In one aspect, the source52could transmit the beam59at first angle θ with respect to an axis116of the nozzle outlet46and/or the spray pattern112(shown in the horizontal direction by way of example, but could be in the vertical direction as well) so that the reflection114could return to the detector54at a second angle α. Accordingly, the detector54could then detect the reflection114in a first state120, with particular intensities at varying wavelengths, corresponding to the known good state as shown inFIG. 5A, then at a later time, in the second state122, corresponding to the bad state as shown inFIG. 5B.

Still referring toFIG. 3, the controller110can also be in communication with a Human Machine Interface (HMI)150and a data structure152. The HMI150may consist of a graphical display, such as a touchscreen monitor, warning lights, keyboard and/or other I/O positioned in the operator cab14. The data structure152may include a table, database and/or other objects stored in a non-transient computer readable medium, such as a mass storage device or memory. The data structure152may hold a first data set154consisting of calibration patterns for the multiple spray nozzle assemblies26, each corresponding to discharge of fluid at respective nozzle outlet46. In one aspect, the first data set154may consist of a single predetermined calibration pattern for a substantially new nozzle outlet which may be implemented in the system for comparison to each of the spray nozzle assemblies26. In another aspect, the first data set154may consist of multiple unique calibration patterns customized for particular spray nozzle assemblies26which may be obtained by sampling the spray nozzle assemblies26when substantially new (or initially deployed). The data structure152may also hold a second data set156consisting of detection patterns for the spray nozzle assemblies26each time the controller110executes to sample the spray nozzle assemblies26.

Referring also toFIG. 6, in one aspect of operation, the controller110may receive one or more calibration patterns, such as via an initial sampling by the pattern detection system27with each of the spray nozzle assemblies26of the field spraying system10fully on, and/or retrieval of one or more predetermined models or libraries (step160). The controller110may store such calibration patterns in the first data set154of the data structure152(step162). Next, the controller110may receive detection patterns, via pattern detection systems27, with each of the spray nozzle assemblies26of the field spraying system10turned on (step164). These flow measurements may occur, for example, while spraying in the field.

In decision step166, the controller110can compare each of the detection patterns to each of the respective calibration patterns to determine an error for each of the spray nozzle assemblies26, such as the first state120(good state) exceeding the second state122(bad state) by at least a predetermined threshold, if errors for the spray nozzle assemblies26are within the predetermined threshold, such as within ±10%, the process may periodically return to step164and repeat. However, if the error for any of the spray nozzle assemblies26exceeds the predetermined threshold, the controller110may generate an alert (step168). The alert may be visually displayed to an operator of the field spraying system10, such as via the HMI150, and the alert may indicate which spray nozzle assembly26exceeded the tolerance.