WO2023161763A1 - Apparatus, system, and method for measuring soil conditions - Google Patents

Abstract

A method uses measuring devices to measure soil conditions. Each device includes a position receiver, at least one soil sensor, a transmitter, a processor in communication with the at least one soil sensor and the transmitter, a power source connected to the processor, and a rigid enclosure containing the at least one soil sensor, the transmitter, the processor, and the power source. The measuring devices may be moved during an agricultural field operation, such as tilling, planting, harvesting, etc.

Description

APPARATUS, SYSTEM, AND METHOD FOR MEASURING SOIL CONDITIONS CROSS-REFERENCE TO RELATED APPLICATION [0001] This application claims the benefit of the filing date of U. S. Provisional Patent Application 63/268,651, “Apparatus, System, and Method for Measuring Soil Conditions,” filed February 28, 2022, the entire disclosure of which is incorporated herein by reference. FIELD [0002] Embodiments of the present disclosure relate generally to monitoring of soil conditions in agricultural fields. BACKGROUND [0003] Traditionally, crops are monitored visually by growers who regularly walk crop fields throughout the growing season. Crops are monitored for problematic weeds, pests, and diseases. Crops may show visual symptoms of stress caused by nutrient deficiency, which may be discovered by walking the crop. In more recent times, technology has been used to monitor crops remotely from satellites or drones. Furthermore, agronomic challenges may be predicted through modelling using past crop planting and harvesting records, weather records, specific crop demands, and varietal resistance by way of example. Soil and tissue testing are also commonly undertaken to obtain a more precise assessment of disease or nutrient levels. [0004] The soil alone usually cannot supply the nutrients required to grow a crop with optimized profit. As such, one or more applications of fertilizer are made, these often being in significant quantities for macronutrients such as nitrogen, phosphorus, and potassium. It is understood that the quantity and timing of fertilizer applications should be selected to minimize pollution and waste and operating costs while meeting the requirements of the growing crop to optimize yield and thus profit. This is especially true of nitrogen, which is critical for protein building and is prone to leaching through the soil profile. [0005] In current practice, it is common for a farmer to physically gather soil at multiple locations in the field and send those soil samples to a lab for analysis of composition, including elemental analysis, organic matter, pH, and moisture. However, the time between gathering the sample to the analysis in a lab at a distant location can be days or weeks. Furthermore, it requires a significant amount of labor to collect the samples, package and ship the samples, and then analyze the samples. Because of the costs and difficulty in performing the tests, many fields may be sampled and tested once per year or once every two years. [0006] Farmers may also perform some tests in the field at other times, such as with test strips. Such tests may provide limited additional data to supplement the samples sent off to a lab (e.g., the tests may be more frequent and/or at more locations within the field). These additional tests can indicate current nutrient levels of the soil and can be used to identify what nutrients should be applied to the field at various times throughout the growing season. BRIEF SUMMARY [0007] In some embodiments, a method includes distributing a plurality of measuring devices beneath a surface of an agricultural field, determining first locations of each of the measuring devices, measuring at least one property of soil at the first locations with the measuring devices, and transmitting, from each measuring device, data representative of the first locations and the at least one property of soil to a computing device remote from the measuring devices. At least some of the measuring devices are moved during an agricultural field operation, and the method further includes determining second locations of each of the measuring devices, measuring the at least one property of soil at the second locations with the measuring devices, and transmitting, from each measuring device, data representative of the second locations and the at least one property of soil to the computing device. Each measuring device includes a position receiver; at least one soil sensor; a transmitter; a processor in communication with the position receiver, the at least one soil sensor, and the transmitter; a power source connected to the processor; and a rigid enclosure containing the position receiver, the at least one soil sensor, the transmitter, the processor, and the power source. [0008] The method may also include determining a location of each of the measuring devices based on an electromagnetic signal. A map of the agricultural field may be generated to represent the at least one property of the soil as measured by the measuring devices. [0009] A field operation may be selected based on the at least one property of the soil as measured by the measuring devices. [0010] Data may be received from at least one of the measuring devices at a computing device remote from the measuring devices. In some embodiments, the data measured by multiple measuring devices is received via the at least one of the measuring devices. [0011] The at least one property may be measured continuously or periodically, such as at a preselected interval. The preselected interval, if used, may be a function of temperature. Transmitting data may also be performed continuously or periodically, in similar manner. [0012] Measurement of the at least one property of soil and/or transmission of data may be terminated when a soil temperature drops below a threshold. [0013] The agricultural field operation may cause movement of some of the measuring devices, and may include planting the agricultural field, tilling the agricultural field, and/or harvesting crop from the agricultural field. The measuring devices remain beneath the soil surface during such operations. [0014] The at least one property may include, for example, a temperature within the enclosure, a concentration of an element (e.g., N, P, K, S, Mg, Ca, Na, Fe, Al, Mn, Cu, Zn, and/or B), a concentration of a compound, a concentration of an ion (e.g., nitrate), a concentration of organic matter, soil pH, cation exchange capacity, and moisture content. [0015] Within the scope of this application it should be understood that the various aspects, embodiments, examples, and alternatives set out herein, and individual features thereof may be taken independently or in any possible and compatible combination. Where features are described with reference to a single aspect or embodiment, it should be understood that such features are applicable to all aspects and embodiments unless otherwise stated or where such features are incompatible. BRIEF DESCRIPTION OF THE DRAWINGS [0016] While the specification concludes with claims particularly pointing out and distinctly claiming what are regarded as embodiments of the present disclosure, various features and advantages may be more readily ascertained from the following description of example embodiments when read in conjunction with the accompanying drawings, in which: [0017] FIG.1 is a simplified top view of an agricultural field and measuring devices; [0018] FIG.2 is a simplified side view of one of the measuring devices shown in FIG.1; and [0019] FIG.3 is a simplified cross-sectional view of the measuring device shown in FIG.2. DETAILED DESCRIPTION [0020] The illustrations presented herein are not actual views of any particular device or portion thereof, but are merely idealized representations to describe example embodiments of the present disclosure. Additionally, elements common between figures may retain the same numerical designation. [0021] The following description provides specific details of embodiments. However, a person of ordinary skill in the art will understand that the embodiments of the disclosure may be practiced without employing many such specific details. Indeed, the embodiments of the disclosure may be practiced in conjunction with conventional techniques employed in the industry. In addition, the description provided below does not include all the elements that form a complete structure or assembly. Only those process acts and structures necessary to understand the embodiments of the disclosure are described in detail below. Additional conventional acts and structures may be used. The drawings accompanying the application are for illustrative purposes only, and are thus not drawn to scale. [0022] As used herein, the terms “comprising,” “including,” “containing,” “characterized by,” and grammatical equivalents thereof are inclusive or open-ended terms that do not exclude additional, unrecited elements or method steps, but also include the more restrictive terms “consisting of” and “consisting essentially of” and grammatical equivalents thereof. [0023] As used herein, the term “may” with respect to a material, structure, feature, or method act indicates that such is contemplated for use in implementation of an embodiment of the disclosure, and such term is used in preference to the more restrictive term “is” so as to avoid any implication that other, compatible materials, structures, features, and methods usable in combination therewith should or must be excluded. [0024] As used herein, the term “configured” refers to a size, shape, material composition, and arrangement of one or more of at least one structure and at least one apparatus facilitating operation of one or more of the structure and the apparatus in a predetermined way. [0025] As used herein, the singular forms following “a,” “an,” and “the” are intended to include the plural forms as well, unless the context clearly indicates otherwise. [0026] As used herein, the term “and/or” includes any and all combinations of one or more of the associated listed items. [0027] As used herein, spatially relative terms, such as “beneath,” “below,” “lower,” “bottom,” “above,” “upper,” “top,” “front,” “rear,” “left,” “right,” and the like, may be used for ease of description to describe one element’s or feature’s relationship to another element(s) or feature(s) as illustrated in the figures. Unless otherwise specified, the spatially relative terms are intended to encompass different orientations of the materials in addition to the orientation depicted in the figures. [0028] As used herein, the term “substantially” in reference to a given parameter, property, or condition means and includes to a degree that one of ordinary skill in the art would understand that the given parameter, property, or condition is met with a degree of variance, such as within acceptable manufacturing tolerances. By way of example, depending on the particular parameter, property, or condition that is substantially met, the parameter, property, or condition may be at least 90.0% met, at least 95.0% met, at least 99.0% met, or even at least 99.9% met. [0029] As used herein, the term “about” used in reference to a given parameter is inclusive of the stated value and has the meaning dictated by the context (e.g., it includes the degree of error associated with measurement of the given parameter). [0030] With reference to FIG.1, a soil monitoring system includes a set of measuring devices 200 distributed across an agricultural field 100, which may have a crop planted in rows 102 or spread throughout the agricultural field 100. The soil monitoring system is not to be limited by the crop in which the system is implemented but, for completeness and by way of example only, the crop may be maize, a cereal, canola, beans, or sugar cane. It should also be understood that the soil monitoring system may have application in non-agricultural crops such as horticultural crops including fruit and vegetable crops. [0031] The measuring devices 200 may be spread at various points throughout the agricultural field 100, and may be placed at strategic points, or at random. There is no limit to the number of measuring devices 200 that may be placed in the agricultural field 100. The measuring devices 200 may typically be covered with soil. [0032] FIG.2 is a simplified side view of one of the measuring devices 200. The measuring device 200 has a rigid, shatter-resistant, and water-resistant enclosure 202 to protect the contents of the measuring device 200. As used here, the term “rigid” means that the enclosure 202 does not significantly deform when stressed. As used herein, the term “shatter-resistant” means that the enclosure 202 does not break when struck or compressed, such as with tillage equipment or a tractor tire. As used herein, the term “water-resistant” means that water cannot pass through the enclosure 202. [0033] For example, the enclosure 202 may be designed to withstand contact with or movement by tillage equipment, planters, harvesters, and other agricultural equipment. That is, if the enclosure 202 is moved or struck by agricultural equipment, the enclosure 202 can protect the components therein. Thus, the measuring device 200 may remain in the soil during tillage, planting, crop treatment, and harvesting operations, even for multiple seasons, though its position and/or orientation may change. [0034] The enclosure 202 may include a first portion 204 and a second portion 206 removably connected to one another. In some embodiments, one or more fastener 208 (depicted as screws in FIG.2) may hold the first portion 204 to the second portion 206. In other embodiments, the first portion 204 and second portion 206 may be shaped to hold together without fasteners 208. For example, the first portion 204 may have a lip into which a ridge formed in the edge of the second portion 206 may snap. In further embodiments, the first portion 204 and second portion 206 may have corresponding threads, and the first portion 204 may screw onto the second portion 206. [0035] The materials of the first portion 204 and the second portion 206 may each be selected such that the assembled enclosure 202 can protect the contents of the measuring device 200 inside the enclosure 202. For example, the portions 204, 206 may be formed of a polymer material (e.g., acrylonitrile butadiene styrene, polycarbonate, high density polyethylene, polypropylene, polyvinyl chloride, acrylic, etc.), a metal (e.g., aluminum, stainless steel, etc.), or any other selected material. The portions 204, 206 may each be formed of a single material, or may include multiple materials. The portions 204, 206 may be formed of the same or different materials. [0036] In some embodiments, the enclosure 202 may include a seal 210 between the first portion 204 and the second portion 206. The seal 210 may include, for example, an elastomeric material in the form of a gasket, an O-ring, etc. The seal 210 may protect the contents of the measuring device 200 from moisture. [0037] FIG.3 is a simplified cross-section of the measuring devices 200. The enclosure 202 may contain various components, such as a soil sensor 302, a position receiver 304, a temperature sensor 306, a processor 308, a power source 310, and a transmitter 312. The soil sensor 302 may be a chemical soil sensor configured to measure an element (e.g., N, P, K, S, Mg, Ca, Na, Fe, Al, Mn, Cu, Zn, B), a compound (e.g., CaNO₃), an ion (e.g., nitrates), organic matter, soil pH, cation exchange capacity (CEC), moisture, or other properties of the soil. [0038] Various types of soil sensors can be adapted for use in the measuring devices 200. For example, sensors for nitrates can include a spectrometer, such as that described in U.S. Patent 10,859,557, "Soil Nitrate Sensing System for Precision Management of Nitrogen Fertilizer Applications," granted December 8, 2020, or electrodes coupled to a differential electrometer, as described in U.S. Patent 9,733,206, “Soil Chemistry Sensor,” granted August 15, 2017. Moisture sensors may include electrodes, which may protrude through the soil sensor 302. Electrodes for measuring soil moisture are described in U.S. Patent 8,981,946, “Soil Moisture Sensor,” granted March 17, 2015. Reflectivity and capacitance sensors can be used to measure soil properties, such as moisture content, as described in U.S. Patent Publication 2020/0245528, “Systems and Apparatuses for Soil and Seed Monitoring,” published August 6, 2020. [0039] The position receiver 304 may be configured to receive a position signal, such as from satellites, fixed-position transmitters, vehicles traveling through the agricultural field 100, or any other source. For example, the position receiver 304 may be a commercially available GPS or GNSS receiver. [0040] The temperature sensor 306 may be configured to measure the temperature of the soil in which the measuring device 200 is placed. The temperature sensor 306 may be, for example, a thermistor, a resistance temperature detector, a thermocouple, a semiconductor- based temperature sensor, etc. [0041] The soil sensor 302, position receiver 304, and temperature sensor 306 may be in electrical communication with a processor 308, which is configured to record and store information received from the soil sensor 302, the position receiver 304, and/or the temperature sensor 306. The processor 308 may also include a memory for storing information, such as operating instructions and data recorded from the soil sensor 302. [0042] The power source 310 (typically a battery) is connected to the processor 308 and configured to provide electric power to the processor 308 and the other components within the enclosure 202. The power source 310 may include a battery, such as an alkaline battery, a lithium-ion battery, an atomic battery, etc. In some embodiments, the power source 310 may include a generation device, such as a coil to generate electricity from a magnetic field, a thermoelectric device, etc. A long-life battery and/or electrical source may be beneficial to enable the measuring device 200 to operate for long periods of time (e.g., one year or longer) without service. [0043] The transmitter 312 is configured to transmit information from the processor 308 when certain conditions are met. For example, the transmitter 312 may transmit information when the temperature sensor 306 detects that the soil temperature is above a certain threshold. When the soil temperature is below the threshold, transmission may be terminated to save power. In one embodiment, the transmitter 312 may be configured to transmit information at certain predetermined times or intervals. In other embodiments, the transmitter 312 may transmit continuously. [0044] The transmitter 312 may operate using established protocols, such as WiFi, Bluetooth, SIM card cellular communication, LoRa communications, etc. The transmitter 312 broadcasts information out to a reader, such as a computer on a vehicle in or over the agricultural field 100, a cell tower, etc. The transmitter 312 of one measuring device 200 may also communicate information to other measuring devices 200 in the agricultural field 100 via a wireless mesh network. An advantage of intercommunication between measuring devices 200 is that the measuring devices 200 can serve as backups for one another in case of malfunction, such that data can be retained. Furthermore, whenever an external receiver is within range to receive data from any one measuring device 200, data may also be collected from interconnected measuring devices 200. [0045] The measuring devices 200 may be used to measure and monitor soil conditions in the agricultural field 100, which may be used to tailor field operations to current conditions. For example, multiple measuring devices 200 can be distributed throughout the agricultural field 100, as shown in FIG.1. The measuring devices 200 may be placed at any time during the season, such as before or after tillage, before or after planting, during the growing season, or during or after harvest. The measuring devices 200 can remain in the soil and collect continuous or periodic data about soil conditions. The measuring devices 200 may have a long- lasting power source 310 and an enclosure 202 robust enough that the measuring devices 200 need not be retrieved before a subsequent planting season. For example, even if the measuring devices 200 are struck and moved during a field operation (e.g., tillage), the measuring devices 200 may still operate as designed. The position receivers 304 may identify the current location of each measuring device 200 based on an electromagnetic signal (e.g., from a GPS/GNSS system, a tower, etc.). The current location is important to identify which part of the agricultural field 100 is being measured, and can also be useful in case an operator needs to retrieve any measuring device 200 (e.g., for maintenance, repair, or replacement). [0046] Data may be collected and/or transmitted continuously at a preselected interval (e.g., daily, hourly, every five minutes, etc.). Furthermore, the frequency of measurement and data transmission may depend on the soil temperature, as measured by the temperature sensor 306. For example, when the temperature is determined to be below a preselected temperature (e.g., 32°F (0°C), 50°F (10°C), etc.), measurement and/or data transmission may be limited or terminated to save power. In some embodiments, the measuring devices 200 may decrease measuring and/or transmitting frequency once the temperature has dropped below the preselected temperature, and may periodically check the temperature to determine whether to begin measuring or transmitting. [0047] Data may be collected from the measuring devices 200 by a computer, which may be at a remote location from the agricultural field 100. For example, the measuring devices 200 may transmit data to a cellular tower or satellite, to a drone flying or driving over the agricultural field 100, or to fixed receiver near the agricultural field 100. The data may then be transferred to the computer via the Internet or other connection. Data from multiple measuring devices 200 may pass through one measuring device 200, such that not all of the measuring devices 200 need to be able to communicate directly with the tower, satellite, or other receiver. That is, one measuring device 200 may act as a repeater or conduit for communications or data from other measuring devices 200, which may be useful for extending the range of existing communications infrastructure to more remote measuring devices 200, or for limiting the number of devices connected to infrastructure. [0048] Information from the measuring devices 200 may be used to select field operations or operating parameters. For example, data from measuring devices 200 may be used to determine when, how, or how much to treat the agricultural field 100 with nutrients, pesticide, herbicide, fungicide, etc. The information may be used to select irrigation amounts and timing. [0049] In some embodiments, the information may be used to generate a map of the agricultural field 100 representing the property(ies) of the soil measured by the measuring devices 200. For example, the map may be stored in a computer for display on a screen, or may be used by a computer program to control a vehicle in the agricultural field 100 (e.g., a sprayer applying a material to the agricultural field 100). [0050] Information from the temperature sensors 306 may be used to select a time for planting crops because it can help the operator know that the soil at the location of each measuring device 200 is warm enough for planting. [0051] In some embodiments, measuring devices 200 in various fields may provide information to a single connected system (e.g., via the internet) to enable an operator of the system to determine where to allocate resources (e.g., to determine which field is ready for planting) without visiting the fields to collect data. [0052] Because the measuring devices 200 can operate throughout a growing season, the operator can have far more data than is available via conventional methods of sending soil samples to a lab for analysis. The operator can see the changes in soil properties over time, and can better tailor operations to the actual field conditions. Particularly with expensive field inputs such as fertilizer (e.g., nitrogen), the amount applied can better match crop needs if soil properties are better characterized. Thus, the operator can achieve better yields with less cost than is possible with conventional sampling techniques. [0053] Furthermore, by deploying multiple measuring devices 200 in the agricultural field 100, the operator can have spatial information about soil properties. Typically, because of the expense of soil sampling, samples are collected from relatively few locations in a field. The measuring devices 200 may be inexpensive enough and provide enough valuable information to justify having many in a field that would previously only have one soil sample taken each year (or longer). [0054] The measuring devices 200 may also be used in grain bins as they are being filled up so that the operator can monitor grain conditions inside the grain bin throughout the winter. As another example, the measuring devices 200 could be put into silage piles or hay bales to monitor location, temperature, and moisture. [0055] A system of the measuring devices 200 may have other benefits as well. For example, data from the measuring devices 200 may be used estimate carbon capture (e.g., by carbon uptake into the plants), which may be used to calculate carbon credits. [0056] All references cited herein are incorporated herein in their entireties. If there is a conflict between definitions herein and in an incorporated reference, the definition herein shall control.

Claims

CLAIMS What is claimed is: 1. A method comprising: distributing a plurality of the measuring devices beneath a soil surface of an agricultural field, each measuring device comprising: a position receiver; at least one soil sensor; a transmitter; a processor in communication with the position receiver, the at least one soil sensor, and the transmitter; a power source connected to the processor; and a rigid enclosure containing the position receiver, the at least one soil sensor, the transmitter, the processor, and the power source; determining first locations of each of the measuring devices; measuring at least one property of soil at the first locations with the measuring devices; transmitting, from each measuring device, data representative of the first locations and the at least one property of soil to a computing device remote from the measuring devices; moving at least some of the measuring devices during an agricultural field operation; determining second locations of each of the measuring devices; measuring the at least one property of soil at the second locations with the measuring devices; and transmitting, from each measuring device, data representative of the second locations and the at least one property of soil to the computing device.

2. The method of claim 1, further comprising generating a first map of the agricultural field representing the at least one property of the soil as measured by the measuring devices at the first locations.

3. The method of claim 2, further comprising generating a second map of the agricultural field representing the at least one property of the soil as measured by the measuring devices at the second locations.

4. The method of any one of claim 1 to 3, further comprising selecting a field operation based on the at least one property of the soil as measured by the measuring devices.

5. The method of any one of claim 1 to 4, further comprising determining the first and second locations of each of the measuring devices based on an electromagnetic signal.

6. The method of any one of claim 1 to 5, wherein receiving data from at least one of the measuring devices at a computing device comprises receiving data measured by multiple measuring devices via the at least one of the measuring devices.

7. The method of any one of claim 1 to 6, wherein measuring at least one property of soil at the first locations with the measuring devices and measuring the at least one property of soil at the second locations with the measuring devices each comprise periodically measuring the at least one property.

8. The method of claim 7, wherein periodically measuring the at least one property comprises measuring the at least one property at a preselected interval.

9. The method of claim 8, wherein the preselected interval is a function of temperature.

10. The method of any one of claim 1 to 9, wherein transmitting data representative of the first locations and the at least one property of soil to a computing device and transmitting data representative of the second locations and the at least one property of soil to a computing device each comprises periodically transmitting data.

11. The method of claim 10, wherein periodically transmitting data comprises transmitting data at a preselected interval.

12. The method of claim 11, wherein the preselected interval is a function of temperature.

13. The method of any one of claim 1 to 12, further comprising terminating measurement of the at least one property of soil when a soil temperature drops below a threshold.

14. The method of any one of claim 1 to 13, further comprising terminating data transmission when a soil temperature drops below a threshold.

15. The method of any one of claim 1 to 14, wherein moving at least some of the measuring devices during an agricultural field operation comprises planting the agricultural field while the measuring devices are beneath the soil surface.

16. The method of any one of claim 1 to 15, wherein moving at least some of the measuring devices during an agricultural field operation comprises tilling the agricultural field while the measuring devices are beneath the soil surface.

17. The method of any one of claim 1 to 16, wherein moving at least some of the measuring devices during an agricultural field operation comprises harvesting crop from the agricultural field while the measuring devices are beneath the soil surface.

18. The method of any one of claim 1 to 17, wherein the at least one property comprises a temperature within the enclosure.

19. The method of any one of claim 1 to 18, wherein the at least one property is selected from the group consisting of a concentration of an element, a concentration of a compound, a concentration of an ion, a concentration of organic matter, soil pH, cation exchange capacity, and moisture content.

20. The method of claim 19, wherein the at least one property comprises a concentration of an element selected from the group consisting of N, P, K, S, Mg, Ca, Na, Fe, Al, Mn, Cu, Zn, and B.

21. The method of claim 19 or claim 20, wherein the at least one soil property comprises a nitrate concentration.