Patent Application
20090242657
1. Field of the Invention
The present invention relates generally to systems and methods for spraying pesticides and other chemicals and, more particularly, to systems and methods that automatically vary the size of droplets released from a nozzle in substantially real-time to control drift associated with spraying pesticides and other chemicals.
2. Description of Related Art
Pesticide or chemical drift is usually discussed in reference to vapor drift and particle drift. Vapor drift involves the evaporation of a pesticide from the soil or crop surface that occurs after application. The vapors are carried by the wind (drift) and then settle on unintended targets. Vapor drift does not depend on the machinery employed to spray the pesticide. Particle or physical drift (sometimes referred to as spray drift) occurs when small drops of sprayed pesticide get carried by the wind and land on unintended targets. Particle drift increases as wind speed increases.
Particle drift, unlike vapor drift can be directly affected by the spray equipment employed (e.g., the type of nozzle). A nozzle has essentially two functions: to meter the amount of liquid that can be sprayed and to create a spray pattern. In an effort to minimize drift, nozzles have been designed to optimize the size of the drop that is sprayed from the nozzle. Two such nozzle types are pre-orifice and turbulation type nozzles. In the pre-orifice nozzle, the two functions (volume and pattern) are separated between two orifices. The first orifice controls the flow into the nozzle and the second orifice controls the spray pattern. This reduces pressure on the liquid as it exits the nozzle resulting in larger drops and thus less drift. In the turbulation type nozzle, a chamber is provided which provides room for the liquid to expand prior to exiting the nozzle. This lowers the pressure behind the liquid that exits the nozzle, thus creating larger drops and less drift.
One type of pre-orifice nozzle is an air-atomizing nozzle. This is a nozzle that draws air into the liquid through a carburetor-like venture. The air and liquid pass through a mixing chamber and are sprayed out together. By introducing air, the nozzle is capable of producing larger drops, which results in less drift. These advancements in nozzle technology have provided the ability to manually adjust the drop size in substantially real time.
In view of the foregoing, it would be advantageous to provide a system for spraying pesticides and other chemicals in such a way that the drop size of the sprayed liquid can be automatically changed in substantially real-time. It would also be advantageous to automatically optimize the drop size in substantially real-time.
Embodiments of the present invention provide systems and methods for spraying chemicals such as pesticides. Some embodiments provide substantial real-time adjustment of the drop size of the sprayed liquid. Some embodiments optimize the drop size to minimize drift. Some embodiments optimize the drop size for other reasons such as amount of chemical needed in a particular area, or to maximize the area of spray, or possibly even to maximize the amount of drift.
An aspect of the invention provides a system for dispersing a liquid and for automatically changing a drop size of the liquid being dispersed in substantially real-time. The system includes a spraying device having at least one nozzle for dispersing liquid. The system also includes a nozzle control device in communication with the nozzle. The nozzle control device is configured to alter a drop size of the dispersed liquid in response to receipt of a control signal. The system includes at least one processor in electrical communication with the nozzle control device which is configured to provide the control signal. The system also includes multiple sensors which are in electrical communication with the processor. The sensors are configured to provide input to the processor about various conditions that could affect drift associated with the sprayed liquid. The control signal is based at least in part on the input from the sensors.
Another aspect of the invention provides a system for dispersing a liquid and for automatically changing a drop size of the liquid being dispersed in substantially real-time. The system includes a spray module configured to disperse liquid through a nozzle, a control module configured to control a drop size of the dispersed liquid in response to receipt of a control signal, a sensor module configured to measure atmospheric conditions and a processor module configured to process the atmospheric conditions, determine a desired drop size based upon the measured atmospheric conditions, compare the desired drop size to the actual drop size and create the control signal to adjust the actual drop size to the desired drop size.
Embodiments of the invention include a method for dispersing a liquid and for automatically changing a drop size of the liquid being dispersed in substantially real-time. The method includes measuring with a sensor at least one atmospheric condition and based at least in part on that measurement, calculating with a processor a desired drop size and comparing the calculated drop size with an actual drop size of a liquid being dispersed through a nozzle. The method also includes determining that the calculated drop size and the actual drop size differ and in response to such a determination creating a control signal with the processor. The method also includes sending the control signal to a nozzle control and the nozzle control adjusting the actual drop size to equal the desired drop size to create a new actual drop size.
The invention will next be described in connection with certain illustrated embodiments; however, it should be clear to those skilled in the art that various modifications, additions and subtractions can be made without departing from the spirit or scope of the claims.
For a better understanding of the present invention, reference is made to the following description, taken in conjunction with the accompanying drawings, in which like reference characters refer to like parts throughout, and in which:
Embodiments of the present invention relate to systems and methods for spraying chemicals and automatically adjusting, in substantially real-time, the drop size of the liquid in the spray. While the invention is especially useful for spraying harmful pesticides it is equally applicable to many other chemical spray applications, e.g. fertilizer, paint, etc. For ease of explanation the remainder of the description shall be limited to pesticides. Those skilled in the art will recognize, however, that the description could be applied to other types of chemicals as well. Also, due to the cost of the system it is particularly useful for large boom type applicators, but it is equally applicable to any system that is employed to disperse chemicals.
A multitude of sensors 20 exist, any combination of which could be employed along with one or more processors 10 and a sprayer to achieve a device in accordance with the present invention. For example, global position systems exist that could be employed to provide both latitude and longitude and topographical maps. To the extent that a topographical map does not exist or is insufficient, or simply for redundancy purposes, radar could be employed to provide additional topographical feedback (including but not limited to crop height, animal concentration, physical hazards such as fences, wall, ditches, etc.). Other sensors 20 that measure humidity, wind speed, wind direction, temperature, flow speed and vehicle speed could be employed to assist in the determination of the optimal drop size. While the previous description of the sensors indicates discrete sensors for each factor, it will be apparent to one skilled in the art that sensors exist which can perform multiple measurements and the use of such multi-measurement sensors falls within the scope of the present invention. Those skilled in the art will also recognize that processor 10 could be a single processor or multiple processors and could be any processor 10 with sufficient processing power to formulate the desired drop size based on the sensors 20 employed. For example, processor 10 could be a microprocessor, a reduced instruction set computer (“RISC”), an application specific integrated circuit (“ASIC”) or combinations of different processor types.
At step 120 of
If the system at step 120 determines that the current drop size is not the same as or falls outside of an acceptable range, it determines at step 130 whether the drop size needs to be increased or decreased. To increase the size of the drop, the processor will send a signal to the nozzle control at step 150 to decrease the pressure of the spray thus increasing the size of the drop. Depending on the type of nozzle employed, this pressure drop can be achieved by decreasing air pressure, increasing or decreasing (depending on the location and purpose of the aperture) one or more apertures of the nozzle and/or increasing the volume of a chamber in the nozzle. Decreasing the air pressure is self explanatory. Increasing or decreasing an aperture can be achieved in any number of conventional ways. For example, servo motors, solenoids or the like may be employed to cause an object such as a conical shaped rod, a cylindrical rod or some other shaped rod to move in or out of the aperture or to place some other form of impediment across a portion of the aperture. Conversely, to decrease the size of the drop the processor will send a signal to the nozzle control at step 140 to increase the pressure of the spray thus decreasing the size of the drop. Depending on the type of nozzle employed, this pressure increase can be achieved by increasing air pressure, decreasing or increasing one or more apertures of the nozzle and/or decreasing the volume of a chamber in the nozzle. This can be achieved by using the methods described in connection with increasing the drop size in reverse. Once the drop size is adjusted, the system returns to step 110.
The previous examples illustrate various possible ways to adjust the drop size of a liquid in a spray based on existing conditions. Those skilled in the art will recognize that this is not an exhaustive list. Many examples exist that were not listed, which also fall within the scope of the invention.
Thus it is seen that systems and methods are provided for spraying chemicals and automatically adjusting, in substantially real-time, the drop size of the liquid in the spray. Although particular embodiments have been disclosed herein in detail, this has been done for purposes of illustration only, and is not intended to be limiting with respect to the scope of the claims, which follow. In particular, it is contemplated by the inventors that various substitutions, alterations, and modifications may be made without departing from the spirit and scope of the invention as defined by the claims. Other aspects, advantages, and modifications are considered to be within the scope of the following claims. The claims presented are representative of the inventions disclosed herein. Other, unclaimed inventions are also contemplated. The inventors reserve the right to pursue such inventions in later claims.
Insofar as embodiments of the invention described above are implemented, at least in part, using a computer system, it will be appreciated that a computer program for implementing at least part of the described methods and/or the described systems is envisaged as an aspect of the present invention. The computer system may be any suitable apparatus, system or device, electronic, optical, or a combination thereof. For example, the computer system may be a programmable data processing apparatus, a general purpose computer, a Digital Signal Processor, an optical computer or a microprocessor. The computer program may be embodied as source code and undergo compilation for implementation on a computer, or may be embodied as object code, for example.
It is also conceivable that some or all of the functionality ascribed to the computer program or computer system aforementioned may be implemented in hardware, for example by one or more application specific integrated circuits and/or optical elements. Suitably, the computer program can be stored on a carrier medium in computer usable form, which is also envisaged as an aspect of the present invention. For example, the carrier medium may be solid-state memory, optical or magneto-optical memory such as a readable and/or writable disk for example a compact disk (CD) or a digital versatile disk (DVD), or magnetic memory such as disk or tape, and the computer system can utilize the program to configure it for operation. The computer program may also be supplied from a remote source embodied in a carrier medium such as an electronic signal, including a radio frequency carrier wave or an optical carrier wave.
