Patent Description:
Windrowers and other self-propelled harvesters have long been used to harvest crops for hay and forage. A conventional windrower includes a laterally extending header supported by a windrower chassis. As the windrower is advanced through a field, the header severs a swath of standing forage plants, such as grasses, alfalfa, wheat, etc. The header also collects the severed forage material and discharges the material rearwardly onto the ground in the form of a windrow extending behind the windrower. Windrowers can employ different types of headers, including sickle headers and rotating disc headers.

The windrow is typically allowed to dry for a period of time, after which the crop is collected and baled. Various factors affect how quickly the cut crop material dries, such as crop moisture, ground moisture, windrow dimensions and density, and crop crimping. To produce high quality bales, the crop should be baled when moisture levels are within certain ranges (which vary by the type of crop). Moisture levels too high can lead to mold or other damage during storage, whereas moisture levels too low can cause excess nutrient loss before baling and difficulty forming coherent bales.

Methods of measuring properties of a harvested crop are disclosed in documents XP055654213, <CIT>, <CIT> and <CIT>.

It would be beneficial to have an efficient way to determine the physical properties of the crop material harvested, including mass and moisture levels, to enable farmers to make better agronomic decisions about processing the crop.

The present invention provides a method of measuring properties of a harvested crop according to claim <NUM> and a non-transitory computer-readable storage medium according to claim <NUM>. Further aspects of the invention are defined in the dependent claims.

The illustrations presented herein are not actual views of any tillage implement or portion thereof, but are merely idealized representations that are employed to describe example embodiments of the present disclosure. Additionally, elements common between figures may retain the same numerical designation.

<FIG> is a simplified diagram illustrating a device and method for measuring a harvested crop. In some embodiments, crop material <NUM> may be laying on a ground surface <NUM>. In other embodiments, the crop material <NUM> may be laying or traveling on a surface of a machine (e.g., a baler, a combine harvester, etc.). In yet other embodiments, the crop material <NUM> may be measured as it is being cut. A measuring device <NUM> measures an attribute of an electric field <NUM> that interacts with the crop material <NUM>. The measuring device <NUM> is within or carried by a frame <NUM> of an agricultural machine, such as a windrower, a baler, a combine harvester, a harvesting header, etc..

The measuring device <NUM> may itself generate the electric field <NUM> and may be operable to change the electric field <NUM>. The electric field <NUM> has a response curve, i.e., its attributes vary in a particular way in response to different conditions. For example, the electric field <NUM> may have a field strength that decreases in proportion to <NUM>/r<NUM> or <NUM>/r<NUM>, where r is the distance from the measuring device <NUM>. The presence of the crop material <NUM> may change a measurable attribute of the electric field <NUM>. For example, if the electric field <NUM> is formed by electromagnetic radiation having a frequency that excites water molecules, moisture within the crop material <NUM> can affect the field lines of the electric field <NUM>. Thus, the shape of the field lines may be the measurable attribute of the electric field <NUM>, which may be detected by the measuring device <NUM>. A change in the amount of moisture in the crop material <NUM>-or a change in the amount (mass) of crop material <NUM>-may change the shape of the field lines. The crop material <NUM> may cause a change in the electrical load provided by the measuring device <NUM> to generate the electric field <NUM>.

The mass of crop material <NUM> and total moisture in the crop material are related: MT = m × MC, where MT is the total moisture in the measurement volume, m is the mass of the crop material <NUM> in the measurement volume, and MC is moisture content of the crop material <NUM>. The total moisture in the measurement volume can be detected based on the measured attribute of the electric field <NUM>. However, without additional information, neither the mass of the crop material <NUM> nor the moisture content of the crop material <NUM> can be determined from the total moisture.

The measuring device <NUM> may generate a second electric field <NUM>, as shown in <FIG>, which may have a different volume than the electric field <NUM> (or, if both fields <NUM>, <NUM> are theoretically boundless, the second electric field <NUM> may have a different response curve). That is, even with the same amount and type of crop material <NUM> in the volume near the measuring device <NUM>, the electric field <NUM> in <FIG> may nonetheless be different than the electric field <NUM> shown in <FIG>. The electric field <NUM> may vary based on a different variable (or combination of variables) than the electric field <NUM>. For example, the shape of the field lines of the electric field <NUM> may vary based on the mass of the crop material <NUM> in the electric field <NUM>. Thus, the measuring device <NUM> may detect two different variables, and these two variables may be used to determine two different properties of the crop material <NUM>. If two different properties of the crop material <NUM> are calculated, confidence in the accuracy of the properties (or at least in one of the properties) is increased.

Though described as measuring attributes of two different electric fields <NUM>, <NUM>, the measuring device <NUM> may measure attributes of any number of electric fields. By determining additional independent attributes, other variables may be determined or derived, even if the variables are dependent on one or more of the variables already determined. Interrelated variables may generally be determined with sufficient independent information (e.g., three independent variables may be used to determine three different properties). Determination of mass and total moisture in the electric fields <NUM>, <NUM> may be combined with a ground speed of the machine or linear speed of the crop material <NUM> to determine mass flow and total moisture flow. Other properties that may be determined include, for example, the position of a top surface of the crop material <NUM> relative to the frame <NUM>, a thickness of the crop material <NUM>, and a density of the crop material <NUM>.

In some embodiments, the electric field <NUM> may be formed by a transmitter powered by a power source within the measuring device <NUM>. If the crop material <NUM> within the electric field <NUM> changes, the amount of power transmitted, and the amount of power drawn from the power source, may change. Thus, the measuring device <NUM> may measure the power draw to correlate to the property of the crop material <NUM>. In some embodiments, the attributes of electric fields <NUM>, <NUM> may be measured by measuring permittivity of the crop material <NUM>.

The crop material <NUM> may be measured as it is harvested by an agricultural machine, meaning that the crop material <NUM> is cut shortly before or as the measuring device <NUM> passes the electric field <NUM> near the crop material <NUM>. In some embodiments, the crop material <NUM> may be measured before being cut.

Though the crop material <NUM> is described herein as being "within the electric field," a person having ordinary skill in the art will understand that electric fields are theoretically infinite, decaying to smaller field strength as distance increases. Thus, the term "within the electric field" herein means within a preselected volume relevant to the electric field, which may be defined by a threshold field strength, physical space boundaries, etc..

<FIG> illustrate another measuring device <NUM> that may be used for measuring a harvested crop <NUM>. As shown, the measuring device <NUM> may be within or carried by a frame <NUM> of an agricultural machine. The measuring device <NUM> may contain a plurality of electrodes <NUM> arranged in an array (e.g., a linear or planar array). For example, <FIG> depict a measuring device <NUM> having seven electrodes 312a-<NUM> in a linear array, though another number of electrodes <NUM> may be used. The electrodes <NUM> may be connected to a power source such that an electric field having field lines <NUM> forms between and adjacent to the electrodes <NUM> and the surroundings. In <FIG>, the center electrode 312d is an electrical sink, and each adjacent electrode 312c, 312e is an electrical source. The remaining electrodes 312a, 312b, 312f, and <NUM> are grounded. Thus, some field lines <NUM> connect the electrical sources to the electrical sink, and other field lines <NUM> connect the shielding electrodes 312a, 312b, 312f, and <NUM> to one another or to ground. The field lines <NUM> associated with the shielding electrodes 312a, 312b, 312f, and <NUM> shield the electrical sources and the electrical sink limit the effects of material within those field lines <NUM>. The hatched area in <FIG> indicates a measurement volume <NUM> in which material can affect the field lines <NUM> related to the electrical sources and electrical sink. The material within the measurement volume <NUM> can affect the magnitude of electric current flowing from the electrical sources to the electrical sink, and the material within a shielded volume <NUM> (i.e., the area not hatched in <FIG>) cannot. The measuring device <NUM> may include a measurement of the current flow from the electrical sources to the electrical sink. As the properties of the material within the measurement volume <NUM> changes, so too may the current. For example, the measuring device <NUM> may measure a resonant frequency of crop material within the measurement volume <NUM>. As the crop material therein changes, the resonant frequency may change or "drift," which is associated with different physical properties of the crop material. Note that the crop material <NUM> is omitted from view in <FIG> for clarity, as is the ground surface <NUM> (see <FIG>).

<FIG> illustrates the same measuring device <NUM>, in which electrical connections of some electrodes <NUM> have been changed. In <FIG>, the center electrode 312d is an electrical sink, and the outermost electrodes 312a, <NUM> are electrical sources. The remaining electrodes 312b, 312c, 312e, and 312f are grounded. Thus, an electric field having field lines <NUM> forms between and adjacent to the electrodes <NUM> and the surroundings. Some field lines <NUM> connect the electrical sources to the electrical sink, and other field lines <NUM> connect the shielding electrodes 312b, 312c, 312e, and 312f to one another. The field lines <NUM> associated with the shielding electrodes 312b, 312c, 312e, and 312f shield the electrical sources and the electrical sink limit the effects of material within those field lines <NUM>. The hatched area in <FIG> indicates a measurement volume <NUM> (extending theoretically to infinity) in which material can affect the field lines related to the electrical sources and electrical sink. The material within the measurement volume <NUM> can affect the magnitude of electric current flowing from the electrical sources to the electrical sink, and the material within a shielded volume <NUM> (i.e., the area not hatched in <FIG>) cannot. Because the measurement volume <NUM> shown in <FIG> is different from the measurement volume <NUM> shown in <FIG>, the measuring device <NUM> may be configurable to yield two different properties of the material therein without physically moving or changing the measuring device <NUM> or the material flow. These two properties may be used to calculate physical properties relevant to operation of the agricultural machine carrying the measuring device <NUM>.

As shown, the volume <NUM> is different from the volume <NUM>, but may partially overlap. That is, some points may be within both the volume <NUM> and the volume <NUM>, and other points may be within one volume <NUM>, <NUM>, but not the other. In certain embodiments, a larger volume in which crop material is measured may be the sum of two or more smaller volumes, and one of the smaller volumes may be measured separately for comparison. For example, in <FIG>, the shaded volume <NUM> may be the smaller volume, and the entire volume below the frame <NUM> may be the larger volume. Alternatively, in <FIG>, the shaded volume <NUM> may be the smaller volume, and the entire volume below the frame <NUM> may be the larger volume. In some embodiments, the volume in which crop material <NUM> is measured may be coextensive with different electric fields. In the embodiment shown in <FIG>, the measuring device <NUM> may measure crop material <NUM> in a certain predefined volume with both fields, though the fields may have different field lines <NUM>, <NUM>.

<FIG> illustrate one way the measuring device <NUM> may be used to measure a material property of the crop material <NUM> by measuring signal attenuation or apparent load on the measuring device <NUM>. That is, the measuring device <NUM> transmits a signal to generate the electric field, and measures the power output, which may vary based on a property (e.g., permittivity) of the crop material <NUM> in the field. <FIG> illustrate one way the measuring device <NUM> may be used to measure received signal strength, resonant frequency, and/or frequency drift as a measure of a material property. Other measuring devices may use other parameters, such as capacitance, as a measure of material properties, and multiple of such other parameters may likewise be used to determine multiple physical properties of crop material, even if those physical properties are interrelated. In some embodiments, combinations of sensors may be used to measure additional properties.

<FIG> is a simplified side view of an example self-propelled windrower <NUM>. In some embodiments, pull-type or other types of harvesting machines may be used. The windrower <NUM> broadly includes a self-propelled tractor <NUM> and a harvesting header <NUM> attached to and carried by the front of the tractor <NUM>. An operator drives the windrower <NUM> from a cab <NUM>, which includes an operator station having a tractor seat and one or more user interfaces (e.g., FNR joystick, display monitor, switches, buttons, etc.) that enable the operator to control various functions of the tractor <NUM> and header <NUM>. In one embodiment, a controller <NUM> or computing system is disposed in the cab <NUM>, though in some embodiments, the controller <NUM> may be located elsewhere or include a distributed architecture having plural computing devices, coupled to one another in a network, throughout various locations within the tractor <NUM> (or in some embodiments, located in part externally and in remote communication with one or more local computing devices).

The header <NUM> includes a cutter <NUM>, a conditioning system, a swathboard <NUM>, and a forming shield assembly <NUM>. The cutter <NUM> is configured for severing standing crops as the windrower <NUM> moves through the field. The conditioning system, in the depicted embodiment, includes one or more pairs of conditioner rolls <NUM>. The forming shield assembly <NUM> may include a pair of rearwardly converging windrow forming shields located behind the conditioner rolls <NUM>. The swathboard <NUM> is located between the conditioner rolls <NUM> and the forming shield assembly <NUM>. In some embodiments, the conditioning system may be of a different design, such as a flail-type conditioning system. In self-propelled harvesters, the forming shields <NUM> are typically supported partly by the header <NUM> and partly by the tractor <NUM>, while in pull-type harvesters the forming shields are typically carried by the header only. In some embodiments, the forming shield assembly may be differently configured (e.g., using a single shield or additional shields of the same or different geometric configuration) to form harvested crop into a windrow having a selected width or shape. The swathboard <NUM> and/or the forming shield assembly <NUM> may be adjusted by one or more actuators <NUM>.

A measuring device <NUM> may be carried by the windrower <NUM> or the header <NUM> such that it can measure the crop material being cut by the header <NUM> and formed into a windrow. The measuring device <NUM> may communicate with the controller <NUM> such that the controller <NUM> can change operating parameters of the windrower <NUM> and/or the header <NUM> (e.g., a position of one or more of the actuators <NUM>). In some embodiments, the measuring device <NUM> may report information to the operator, and the operator may make changes to the operating parameters of the windrower <NUM> and/or the header <NUM>. Changing operating parameters of a windrower <NUM> or header <NUM> based on information about the crop is described in more detail in <CIT>.

In some embodiments, the controller <NUM> may operate the windrower <NUM> autonomously or semi-autonomously. For example, the operator may set initial operating parameters, and may control steering and propulsion of the tractor <NUM>. The controller <NUM> may adjust the position of the swathboard <NUM> and/or the forming shield assembly <NUM> as measured crop conditions change, with or without input from the operator. In certain embodiments, the controller <NUM> may change a ground speed of the tractor <NUM> based on the measured crop conditions.

The measuring devices <NUM>, <NUM> described herein may also be used with other crop-harvesting machines, such as balers, combines, etc..

<FIG> is a simplified flow chart illustrating a method <NUM> of measuring a harvested crop. In block <NUM>, a first attribute of a first electric field is measured in a first volume containing crop material. In block <NUM>, a second attribute of a second electric field is measured in a second volume (which may be the same or different than the first volume). For example, the attributes measured may be resonant frequencies within the volumes. In block <NUM>, at least two different properties of the crop material are determined based at least in part on the first attribute and the second attribute. For example, the properties determined may be permittivity, total moisture content, total mass, location (distance from any point on the sensor to the crop material, which can be used to determine crop orientation, crop distribution, velocity of crop material, etc.), density, percentage moisture, mass flow, and/or total moisture flow. The properties may be determined as the crop material is harvested by an agricultural machine. In block <NUM>, an operating parameter of a crop-harvesting machine is adjusted based at least in part on one of the properties. For example, one or more of the properties may be reported to a controller that operates the agricultural machine, and used by the controller to change the operating parameter.

Still other embodiments involve a computer-readable storage medium (e.g., a non-transitory computer-readable storage medium) having processor-executable instructions configured to implement one or more of the techniques presented herein. An example computer-readable medium that may be devised is illustrated in <FIG>, wherein an implementation <NUM> includes a computer-readable storage medium <NUM> (e.g., a flash drive, CD-R, DVD-R, application-specific integrated circuit (ASIC), field-programmable gate array (FPGA), a platter of a hard disk drive, etc.), on which is computer-readable data <NUM>. This computer-readable data <NUM> in turn includes a set of processor-executable instructions <NUM> configured to operate according to one or more of the principles set forth herein. In some embodiments, the processor-executable instructions <NUM> may be configured to cause a computer associated with the windrower <NUM> (<FIG>) to perform operations <NUM> when executed via a processing unit, such as at least some of the example method <NUM> depicted in <FIG>. In other embodiments, the processor-executable instructions <NUM> may be configured to implement a system, such as at least some of the example windrower <NUM> depicted in <FIG>. Many such computer-readable media may be devised by those of ordinary skill in the art that are configured to operate in accordance with one or more of the techniques presented herein.

Claim 1:
A method of measuring properties of a harvested crop utilising a measuring device within or carried by a frame of an agricultural machine, the method comprising:
generating, utilising the measuring device, a first electrical field in a first volume containing crop material;
measuring a first attribute of the first electric field;
generating, utilising the measuring device, a second electrical field in a second volume containing crop material, the second electrical field having a different volume and/or a different response curve to the first electrical field;
measuring a second attribute of the second electric field; and
determining at least two different properties of the crop material based at least in part on the first attribute and the second attribute.