Raster-based contour swathing for guidance and variable-rate chemical application
A raster-based system for global navigation satellite system (GNSS) guidance includes a vehicle-mounted GNSS antenna and receiver. A processor provides guidance and/or autosteering commands based on GNSS-defined pixels forming a grid representing an area to be treated, such as a field. Specific guidance and chemical application methods are provided based on the pixel-defined treatment areas and preprogrammed chemical application prescription maps, which can include variable chemical application rates and dynamic control of the individual nozzles of a sprayer.
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This application is The present application is a second reissue application of U.S. Pat. No. 8,718,874 filed as U.S. patent application Ser. No. 13/776,512 on Feb. 25, 2013. The present application is a divisional of U.S. patent application Ser. No. 15/147,689, filed May 5, 2016, now U.S. Pat. No. RE47,055, issued Sep. 25, 2018, which is a reissue of U.S. patent application Ser. No. 13/776,512, filed Feb. 25, 2013, now U.S. Pat. No. 8,718,874, issued May 6, 2014, which is a continuation of and claims priority in U.S. patent application Ser. No. 12/689,184, filed Jan. 18, 2010, now U.S. Pat. No. 8,386,129, issued Feb. 26, 2013, which claims priority in U.S. Provisional Patent Application Ser. No. 61/145,542, filed Jan. 17, 2009, both of which are incorporated herein by reference.
BACKGROUND OF THE INVENTION1. Field of the Invention
The present invention relates generally to automated equipment control using a raster-based database, including vehicle navigation and guidance using global navigation satellite system (GNSS), inertial navigation system (INS) and other positioning inputs, and machine control functions such as variable-rate chemical applications in agricultural spraying.
2. Description of the Related Art
GNSS technology advanced vehicle and machine guidance and control in various technical fields, including the field of agricultural guidance by enabling reliable, accurate systems, which are relatively easy to use. GNSS guidance systems are adapted for displaying directional guidance information to assist operators with manually steering the vehicles. For example, the OUTBACK® steering guidance system, which is available from Hemisphere GPS LLC of Calgary, Alberta, Canada and is covered by U.S. Pat. Nos. 6,539,303 and 6,711,501 (incorporated herein by reference), includes an on-board computer capable of storing various straight-line and curved (“contour”) patterns. An advantage of this system is its ability to retain field-specific cultivating, planting, spraying, fertilizing, harvesting and other patterns in memory. This feature enables operators to accurately retrace such patterns. Another advantage relates to the ability to interrupt operations for subsequent resumption by referring to system-generated logs of previously treated areas. The OUTBACK S steering guidance system, and related product offerings from Hemisphere GPS LLC, utilize “near point search method” technology, which logs GPS-defined positions along swath edges, the nearest of which are located for placing the edge of the next swath against the last.
Another type of GPS guidance utilizes “form line following,” wherein vectors, which can be straight-line (A-B) or curved (contour), are computed based on equipment widths offset from the previously-driven form lines. A disadvantage with this type of system is that initial form lines must be driven and delineated based upon which subsequent form lines must be computed and followed. Significant computer overhead can be occupied with such tasks, whereby trade-offs are required between component costs and system responsiveness.
GNSS vehicle guidance equipment using the above techniques is available as a steering guide with a graphical user interface (GUI) for manually-steered vehicles, and also with an autosteer function for automatically steering the vehicle along all or part of its travel path. Automated systems can also control an agricultural procedure or operation, such as spraying, planting, tilling, harvesting, etc. Examples of such equipment are shown in U.S. Pat. No. 7,142,956, which is incorporated herein by reference. U.S. Patent Application Publication No. 2004/0186644 shows satellite-based vehicle guidance control in straight and contour modes, and is also incorporated herein by reference. U.S. Pat. No. 7,162,348 is incorporated herein by reference and discloses an articulated equipment position control system and method whereby a working component, such as an implement, can be guided independently of a motive component, such as a tractor. The implement can optionally be equipped with its own GNSS antenna and/or receiver for interacting with a tractor-mounted GNSS system.
Ideally crops would be planted in perfectly straight, evenly-spaced rows. Guidance through such fields would consist of following relatively simple straight-line patterns. Such guidance modes are commonly referred to as straight line or “A-B” in reference to the equipment traveling in a straight line from point A to point B in a repeating pattern in order to cover an entire field, which is typically flat and rectangular and therefore efficiently divided into multiple, parallel swaths. However, field conditions in many areas are not suitable for A-B guidance. For example, hilly terrain sometimes requires the formation of constant-elevation terraces.
Guidance systems accommodate such irregular conditions by operating in “contour following” modes consisting of curvilinear tracks defined by multiple GNSS points along which the equipment is guided. Initial planting passes made with manual and visually-guided navigation, which may or may not be supplemented with GNSS navigational aids, can cause crop rows to deviate from straight lines. Accommodating such irregular crop rows in subsequent operations (e.g., spraying and harvesting) may require the equipment to deviate from straight-line passes.
“Tramline” (sometimes referred to as “match tracks”) is another operating mode available with some modern GNSS guidance systems. In tramline operating mode the existing crop rows are relatively well protected because the equipment follows or “matches” the previously-driven passes. The equipment wheels or tracks are thus confined between the crop rows. Machine damage from running over crops is thus avoided, or at least minimized.
Preferably a system embodying an aspect of the present invention would avoid the drawbacks inherent in the previous systems described above and be adaptable to various machine control applications, including variably controlling the output of individual nozzles in agricultural sprayers. In particular, raster (e.g., bitmap) data bases can be used with previously-defined world geodetic systems, such as WGS 84, thereby eliminating overhead-intensive tasks such as continuously running extensive searches for points along the edges of previously-driven swaths or computing form lines.
Heretofore there has not been available a raster-based contour swathing system and method with the advantages and features of the present invention.
SUMMARY OF THE INVENTIONIn the practice of the present invention, a system and method are provided for automatically guiding and controlling vehicles and equipment using GNSS for defining a raster-based database of pixels defining either an entire area to be treated, or a subset through which a vehicle travels. For example, agricultural equipment comprising a tractor and an implement can be equipped with a vector position and heading sensor subsystem including a GNSS receiver and antennas and an optional inertial navigational system (INS) with X, Y and Z axis sensors for sensing equipment attitude changes through six degrees of freedom. Such sensors typically comprise gyroscopes and/or accelerometers. A 2D map array comprises an XY grid of pixels, which is scalable according to the requirements of a particular operation. Guidance operations are accomplished by marking pixels as “applied” when treated on an equipment pass. Subsequent passes can guide off of the applied pixel areas, using “target” aim point pixels and/or swath-width spacing to one side or the other of the applied areas. Moreover, machine control functions can actuate certain operations based on equipment position. For example, spray nozzles on a sprayer implement can be selectively and individually actuated over areas to be sprayed.
I. Introduction and Environment
As required, detailed embodiments of the present invention are disclosed herein; however, it is to be understood that the disclosed embodiments are merely exemplary of the invention, which may be embodied in various forms. Therefore, specific structural and functional details disclosed herein are not to be interpreted as limiting, but merely as a basis for the claims and as a representative basis for teaching one skilled in the art to variously employ the present invention in virtually any appropriately detailed structure.
Certain terminology will be used in the following description for convenience in reference only and will not be limiting. For example, up, down, front, back, right and left refer to the invention as oriented in the view being referred to. The words “inwardly” and “outwardly” refer to directions toward and away from, respectively, the geometric center of the embodiment being described and designated parts thereof Global navigation satellite systems (GNSS) are broadly defined to include GPS (U.S.), Galileo (proposed), GLONASS (Russia), Beidou (China), Compass (proposed), IRNSS (India, proposed), QZSS (Japan, proposed) and other current and future positioning technology using signals from satellites, using single or multiple antennae, with or without augmentation from terrestrial sources. Inertial navigation systems (INS) include gyroscopic (gyro) sensors, accelerometers and similar technologies for providing output corresponding to the inertia of moving components in all axes, i.e. through six degrees of freedom (positive and negative directions along transverse X, longitudinal Y and vertical Z axes). Yaw, pitch and roll refer to moving component rotation about the Z, X and Y axes respectively. Said terminology will include the words specifically mentioned, derivatives thereof and words of similar meaning.
II. Guidance and Control System 4
Referring to the drawings in more detail, the reference numeral 2 generally designates a piece of agricultural equipment, which is equipped with a raster-based guidance and control system 4 embodying an aspect of the present invention. Without limitation on the generality of equipment 2, a motive component 6 is connected to a working component 7 through an optional articulated connection or hitch 34 (collectively comprising the equipment or vehicle 2). Also by way of example, the motive component 6 can comprise a tractor or other vehicle and the working component 7 can comprise a ground-working implement. However, the system 4 can be applied to other equipment configurations for a wide range of other applications. Such applications include equipment and components used in road construction, road maintenance, earthworking, mining, transportation, industry, manufacturing, logistics, etc.
An implement steering subsystem 36 receives steering commands from the guidance processor CPU 23 via a CAN bus 32 or some other suitable connection, which can be wireless. The implement 7 is mechanically connected to the vehicle 6 by a hitch 34, which can be power-driven for active implement positioning in response to implement steering commands, or a conventional mechanical linkage. The hitch 34 can be provided with sensors for determining relative attitudes and orientations between the vehicle 6 and the implement 7. Examples of such an articulated connection and an implement steering system are described in U.S. Pat. Nos. 6,865,465, 7,162,348 and 7,460,942, which are incorporated herein by reference. The implement 8 can comprise any of a wide range of suitable implements, such as planting, cultivating, harvesting and spraying equipment. For example, spraying applications are commonly performed with a boom 5, which can be equipped for automatic, selective control of multiple nozzles 8 and other boom operating characteristics, such as height, material dispensed, etc. By way of example and without limitation, the implement 7 can comprise an agricultural sprayer with a spray nozzle control 38 connected to the guidance processor CPU 23 by the CAN bus 32 for individually controlling the spray nozzles 8.
The GNSS/INS guidance and control system 4 can be configured in various combinations of components and thereby accommodate a wide range of guidance and control operations. For example, RTK guidance can be accommodated with a base 44 including an RTK receiver 46 and an RTK transmitter 48, which can be mounted at a fixed-position reference point in the general vicinity of fields being worked by the equipment 2. Moreover, various combinations of receivers and antennas can be used on the vehicle 6 and/or the implement 7, including single frequency (L1 only) and dual frequency (L1 and L2). Various forms of signal correction can also be utilized, including Satellite Based Augmentation System (SBAS), Wide Area Augmentation System (WAAS) and private subscription services.
The GNSS receiver 12 disclosed herein can be adapted for various satellite navigational systems, and can utilize a variety of SBAS technologies. Technology is also available for continuing operation through satellite signal interruptions, and can be utilized with the system 4. The antennas 21, 22 can be horizontally aligned transversely with respect to a direction of travel of the tractor 6, i.e. parallel to its transverse X axis. The relative positions of the antennas 21, 22 with respect to each other can thus be processed for determining yaw, i.e. rotation with respect to the vertical Z axis. The INS 31 can include inertial sensors (e.g., gyroscopes and accelerometers) for detecting and measuring inertial movement with respect to the X, Y and Z axes corresponding to yaw, roll and pitch movements in six degrees of freedom. Signals from the receiver 12 and the INS sensors are received and processed by the microprocessor 26 based on how the system 4 is configured and programmed
III. Raster-based Guidance and Control Method
Setup of a raster-based database (DB) of XY pixel grid pages 48 occurs at 46. An example of a pixel grid page 48 is shown in
In an exemplary field spraying operation using the sprayer 7, the equipment 2 is driven in an initial pass at 66 in a “swath” mode with its swath width comprising one of the operating parameters whereby all pixels covered by the spray boom 5 are marked as “applied” (50a in
As shown in
As shown in
In conjunction with the methods described above, variable rate control can be accomplished using multiple channels for individual nozzle control of chemical applications. For example, the CAN bus 32 communicates individual nozzle control commands from the processor 23 to the spray nozzles 8, which can be monitored and boom pressure controlled thereby for correct calibration. Individual nozzle flow rate control across the entire spray boom accommodates swath overlaps whereby spray nozzle output would be reduced or shut off. Nozzles 8 can also be shut off upon entry into previously-applied areas and no-spray areas, such as outside the field boundaries.
The pixel status in the method of the present invention includes information on the chemical(s) application rates(s). As the spray boom 5 crosses the treatment area the database is read for each nozzle 8 location and the desired rates per area, e.g. gallons per acre. The nozzle flow rate is then adjusted to the required output, e.g., in gallons per minute (GPM) based on the current nozzle speed. The amount of coverage during turning of the vehicle can also vary according to the nozzle locations in the turn, with the outermost nozzle 8 traveling fastest (requiring the greatest flow rate) and the innermost nozzle traveling slowest (requiring the least flow rate). Such speeds can vary considerably in turns and are accommodated by the system 4.
Alternative algorithms can be utilized for managing chemical application. For example, in a “rate reduction to zero” algorithm the application rates can be progressively reduced on one or more passes as required to “zero out” the applied material quantities across the boom widths whereby on subsequent passes the applied rate will be zero gallons per acre. Alternatively, in an “as applied map” algorithm the application rates can be read back in real time from the processor 23 and subtracted from the desired target rate per pixel and written back as the remaining desired rates with a flag indicating partial application marking the partially-treated (under-applied) pixels 50f. The real time database display reflects the remaining rates required for each pixel, the remaining chemical required for the completion of the field area and the remaining quantities available.
Various output information can be provided to an operator, e.g., indicating pixel status originally and currently, “as applied” mapping and remaining chemical application rates by pixel for job completion. By individually controlling the flow rates at the nozzles 8, the desired prescription map area rate can be achieved, thereby optimizing variable rate coverage for increased crop production. Less-experienced operators can be accommodated because the system 4 reduces the likelihood of over-application or application outside the field perimeter.
It is to be understood that the invention can be embodied in various forms, and is not to be limited to the examples discussed above.
Claims
1. A method of guiding an agriculture sprayer vehicle including a motive component and a spray component with a spray boom having opposite ends and multiple spray nozzles mounted in spaced relation between said ends, said components being interconnected by a power hitch adapted for laterally shifting said working component relative to said motive component, which method comprises the steps of:
- providing an XY pixel grid corresponding to the area;
- providing a raster-based database page comprising said XY pixel grid for said area;
- providing a processor on the vehicle;
- providing a GNSS guidance system connected to the processor on the vehicle;
- receiving GNSS positioning signals with said guidance system;
- providing said GNSS positioning signals as input to said processor;
- computing GNSS-based positioning for said vehicle with said processor;
- defining a GNSS-defined reference point on said area and storing the reference point coordinates with said processor;
- computing X and Y pixel indices based on said GNSS-defined vehicle position in relation to said reference point with said processor;
- treating portions of said area with said working component;
- with said processor marking pixels in said treated area portions as treated;
- guiding said vehicle over said area utilizing said treated pixel information;
- defining additional raster-based XY pixel grid pages in said area;
- expanding said database by tiling said pixel grid pages over said area;
- generating X and Y scale factors for said database;
- relating said X and Y scale factors to latitude and longitude respectively;
- computing X and Y pixel indices based on the difference between current GNSS-defined position coordinates and the reference position coordinates;
- creating with said processor a linear or multidimensional database comprising said pixel grid pages;
- accessing with said processor said database;
- marking pixels in said database as treated;
- defining a swath coverage area with said working component ends forming opposite edges of said swath;
- with said GNSS system and said processor seeking pixels in proximity to said swath edges;
- with said GNSS system and said processor guiding said vehicle along said swath edges;
- providing an autosteer system on said vehicle;
- with said processor generating steering commands using the marked pixel information and said XY pixel page database;
- outputting said steering commands to said autosteer system for automatically steering said vehicle over said area;
- with said processor and said GNSS system laterally shifting said working component relative to said motive component for maintaining said working component generally within said swath;
- computing an application map for said area corresponding to treatments of pixels therein with said working component;
- guiding said vehicle with said application map while treating said pixels; and
- detecting a vehicle direction of travel with said GNSS system;
- walking up the pixels in the vehicle direction of travel to a target pixel;
- testing pixels in multiple scans alongside said vehicle path for treated conditions based on a swath width of said working component;
- guiding said vehicle towards said target pixel using said treated condition pixel information alongside said vehicle path;
- testing multiple distances ahead for treated pixels;
- detecting a curve condition defined by treated pixels;
- guiding said vehicle alongside said curve using said treated pixel information;
- preprogramming said processor with variables corresponding to vehicle performance dynamics;
- determining altitudes of said pixels with said GNSS system; and
- adjusting guidance and steering for vehicle slippage, sloping surface chemical spray patterns and crop heights using said vehicle performance dynamics and said pixel altitudes.
2. A memory storing instructions that, when executed by at least one processing device of an agriculture vehicle that includes a motive component and a working component, cause the at least one processor to perform operations including:
- providing an XY pixel grid page corresponding to an area, the grid page including pixels associated with different portions of the area;
- guiding the agricultural vehicle in an initial pass over the area corresponding to the grid page;
- during the initial pass of the area, marking the pixels in the XY pixel grid page associated with portions of the area treated by the working component as applied pixels;
- during another pass of the area, detecting a vehicle path with at least one sensor of the vehicle;
- walking up pixels in the XY pixel grid page along the vehicle path to a target pixel in the XY pixel grid page;
- testing the pixels in the XY pixel grid page alongside the vehicle path for the applied pixels based on a swath width of the working component; and
- guiding the vehicle towards the target pixel based on applied pixels identified alongside the vehicle path.
3. The memory of claim 2, wherein the operations further include:
- testing multiple distances ahead for the applied pixels;
- detecting a curve defined by the applied pixels; and
- guiding the vehicle alongside the curve defined by the applied pixels.
4. The memory of claim 2, wherein the operations further include:
- determining altitudes for the identified portions of the area;
- assigning the altitudes to the pixels associated with the identified portions of the area; and
- adjusting guidance and steering of the vehicle based on the altitudes assigned to the pixels associated with the portions of the area covered by the working component.
5. The memory of claim 2, wherein the operations further include:
- defining additional XY pixel grid pages; and
- combining the additional XY pixel grid pages with the provided XY pixel grid page.
6. The memory of claim 2, wherein the operations further include:
- identifying a swath coverage area with swatch edges corresponding with opposite ends of the working component;
- identifying the pixels in proximity to the swath edges; and
- steering the vehicle based on the pixels in proximity to the swath edges.
7. The memory of claim 2, wherein the operations further include:
- assigning chemical prescription rate values to the pixels;
- compute amounts of a chemical applied to the portions of the area;
- compare the amounts of the chemical applied to the portions of the area with the target chemical prescription rate values assigned to the pixels associated with the portions of the area; and
- adjusting the amounts of additional chemical output from individual spray nozzles of the working component on the portions of the area based on the comparisons of the amounts of the chemical previously applied to the portions of the area and the chemical prescription rate values assigned to the pixels associated with the portions of the areas.
8. The memory of claim 2, wherein the operations further include detecting and measuring inertial movement using a gyroscope and accelerometer on the vehicle.
9. A method of operating an agriculture vehicle that includes a motive component and a working component, the method comprising:
- providing an XY pixel grid page corresponding to an area, the grid page including pixels associated with different portions of the area;
- guiding the agricultural vehicle in an initial pass over the area corresponding to the grid page;
- during the initial pass of the area, marking the pixels in the XY pixel grid page associated with portions of the area treated by the working component as applied pixels;
- during another pass of the area, detecting a vehicle path with at least one sensor of the vehicle;
- walking up pixels in the XY pixel grid page along the vehicle path to a target pixel in the XY pixel grid page;
- testing the pixels in the XY pixel grid page alongside the vehicle path for the applied pixels based on a swath width of the working component; and
- guiding the vehicle towards the target pixel based on applied pixels identified alongside the vehicle path.
10. The method of claim 9, further comprising:
- testing multiple distances ahead for the applied pixels;
- detecting a curve defined by the applied pixels; and
- guiding the vehicle alongside the curve defined by the applied pixels.
11. The method of claim 9, further comprising:
- determining altitudes for the identified portions of the area;
- assigning the altitudes to the pixels associated with the identified portions of the area; and
- adjusting guidance and steering of the vehicle based on the altitudes assigned to the pixels associated with the portions of the area covered by the working component.
12. The method of claim 9, further comprising:
- defining additional XY pixel grid pages; and
- combining the additional XY pixel grid pages with the provided XY pixel grid page.
13. The method of claim 9, further comprising:
- identifying a swath coverage area with swatch edges corresponding with opposite ends of the working component;
- identifying the pixels in proximity to the swath edges; and
- steering the vehicle based on the pixels in proximity to the swath edges.
14. The method of claim 9, further comprising:
- assigning chemical prescription rate values to the pixels;
- compute amounts of a chemical applied to the portions of the area;
- compare the amounts of the chemical applied to the portions of the area with the target chemical prescription rate values assigned to the pixels associated with the portions of the area; and
- adjusting the amounts of additional chemical output from individual spray nozzles of the working component on the portions of the area based on the comparisons of the amounts of the chemical previously applied to the portions of the area and the chemical prescription rate values assigned to the pixels associated with the portions of the areas.
15. The method of claim 9, further comprising detecting and measuring inertial movement using a gyroscope and accelerometer on the vehicle.
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Type: Grant
Filed: Aug 2, 2018
Date of Patent: Apr 13, 2021
Assignee: AGJUNCTION LLC (Scottsdale, AZ)
Inventors: John A. McClure (Scottsdale, AZ), Dennis M. Collins (Overgaard, AZ)
Primary Examiner: Robert L Nasser
Application Number: 16/053,650
International Classification: A01B 69/00 (20060101); B62D 6/00 (20060101); A01B 69/04 (20060101); A01B 79/00 (20060101); G05D 1/02 (20200101);