System for detecting gas concentration in soil

Abstract

A system for determining soil gas properties includes a vacuum pump configured to draw soil gas through an air inlet; a gas sensor for measuring gas concentration levels in the soil gas passing through the system; a GPS unit for determining the location of the system; and a controller configured to map measurements from at least one gas sensor relative to the location of the system. The method for determining the soil properties includes drawing a gas sample from the soil through the air inlet; transmitting the gas sample to at least one gas sensor; measuring the gas concentration in the gas sample with the at least one gas sensor; transmitting the measured gas concentration to the controller; determining the location of the air inlet with the GPS unit; transmitting the location to the controller; and mapping the measured gas concentration using the location.

Description

[0001] Cross-references

[0002] This application claims priority to U.S. Provisional Patent Application No. 62 / 968,366, filed on January 31, 2020, and the entire disclosure of which is expressly incorporated herein by reference. Technical Field

[0003] The present invention relates to soil property measurement and assessment, and more particularly, to systems and methods for sampling the concentration of gases and other soil properties in soil for mapping these properties over a desired area. Background Art

[0004] Soil composition, as well as the types and amounts of different substances within it, can influence any performance characteristics used to utilize and evaluate that soil. One example is identifying soils that may be more suitable for growing crops or produce higher yields from crop cultivation. Another example is identifying contaminants within soil to determine whether and how to conduct environmental remediation. While core samples can be used to determine soil composition at specific locations, this and similar methods are severely limited in their effective use. Therefore, there is a need for improved systems and methods that can help determine soil composition in a variety of applications. Summary of the Invention

[0005] To provide a basic understanding of the present invention, a brief summary of some embodiments of the present invention is provided below. This summary is not an extensive overview of the present invention. It is not intended to identify key / important elements of the present invention or to define the scope of the present invention. Its sole purpose is to present some embodiments of the present invention in a simplified form as a prelude to the more detailed description that will be presented later.

[0006] According to one aspect of the present disclosure, a system for determining soil properties, such as gas concentration levels, is provided, the system comprising an air inlet in fluid communication with an air moving device, such as, for example, a vacuum pump, configured to draw soil gas through the air inlet; at least one gas sensor in fluid communication with the air inlet and operable to measure gas concentration levels in gas passing through the system; a GPS unit operable to confirm a location of the system; and a controller in communication with the at least one gas sensor and the GPS unit and configured to map measurements from the at least one gas sensor relative to a location of the system determined by the GPS unit.

[0007] In another aspect, a system for determining soil properties is provided, the system also including a cleaning / recharging subsystem having a pressurized air source; and a switchable valve in fluid communication with the pressurized air source and an air inlet; the switchable valve is operable to selectively connect the pressurized air source to the air inlet fluid.

[0008] In another aspect, a method for determining an association of soil properties is provided, the method comprising the steps of: drawing a gas sample from the soil through an air inlet; transmitting the gas sample to at least one gas sensor; measuring a gas concentration in the gas sample using the at least one gas sensor; transmitting the measured gas concentration to a controller; determining a location of the air inlet using a GPS unit; transmitting the location to the controller; and mapping the measured gas concentration using the location.

[0009] In another aspect, a method for determining soil properties is provided, the method comprising the following steps: providing a system for determining soil properties, the system having an air inlet in fluid communication with a vacuum pump, the vacuum pump being configured to draw soil gas through the air inlet; at least one gas sensor in fluid communication with the air inlet and operable to measure a gas concentration level in gas passing through the system; a GPS unit operable to confirm a location of the system; and a controller in communication with the at least one gas sensor and the GPS unit and configured to map measurements from the at least one gas sensor relative to a location of the system determined by the GPS unit; drawing a gas sample from the soil through the air inlet; transmitting the gas sample to the at least one gas sensor; measuring the gas concentration in the gas sample with the at least one gas sensor; transmitting the measured gas concentration to the controller; determining a location of the air inlet with the GPS unit; transmitting the location to the controller; and mapping the measured gas concentration using the location.

[0010] These aspects are merely examples of countless aspects related to the present invention and should not be considered to be limiting in any way. These aspects, features and advantages of the present invention and other aspects, features and advantages will become apparent from the following detailed description when taken in conjunction with the accompanying drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0011] The foregoing summary, as well as the following detailed description, will be better understood when read in conjunction with the accompanying drawings, in which like or similar elements are designated by like reference numerals, and wherein:

[0012] Figure 1 FIG. 1 is a schematic diagram of a gas property measurement system according to a first embodiment of the present disclosure.

[0013] Figure 2 FIG. 1 is a schematic diagram illustrating the gas flow relationships among components of a gas property measurement system according to another embodiment of the present disclosure.

[0014] Figure 3 FIG. 1 is a schematic diagram illustrating data flow and wiring interrelationships of components of a gas property measurement system according to another embodiment of the present disclosure.

[0015] Figure 4is a graph plotting raw data points generated from one embodiment of the present disclosure, a curve generated by averaging the raw data points, and a polynomial curve generated from the raw data points.

[0016] Figure 5A and Figure 5B is a comparison of field plots of gas concentration samples generated from one embodiment of the present disclosure, depicting both raw and smoothed data.

[0017] Figure 6A and Figure 6B is a comparison of field plots of gas concentration samples generated from one embodiment of the present disclosure, depicting raw data and the same data after correction based in part on calculated measurement delays.

[0018] Figure 7A and Figure 7B is a comparison of field plots of gas concentration samples generated from one embodiment of the present disclosure, depicting raw data and the same data after correction based in part on air velocity through the system and expected CO2 gas concentration levels.

[0019] Figure 8A and Figure 8B is a comparison of field plots of gas concentration samples generated from one embodiment of the present disclosure, depicting raw data and the same data corrected based in part on sensor delay and expected O2 gas concentration levels.

[0020] While the present disclosure is susceptible to various modifications and alternative forms, specific embodiments thereof are shown by way of example in the drawings and will be described in detail herein. However, it should be understood that the drawings and detailed description given herein are not intended to limit the present disclosure to the specific embodiments disclosed, but rather, the present disclosure is intended to cover all modifications, equivalents, and alternatives falling within the spirit and scope of the present disclosure. DETAILED DESCRIPTION

[0021] In the detailed description that follows, many specific details are set forth in order to provide a thorough understanding of the present invention. However, it will be understood by those skilled in the art that the present invention may be practiced without these specific details. For example, the scope of the present invention is not limited to the specific types of industrial applications depicted in the accompanying drawings. In other cases, well-known methods, processes, and components are not described in detail to avoid obscuring the present invention. The following descriptions of the technology are merely exemplary in nature with respect to the subject matter, manufacture, and use of one or more inventions and are not intended to limit the scope, application, or use of any particular invention claimed in this application, or in other applications that may be filed claiming priority to the present application, or patents issued therefrom. The following definitions and non-limiting criteria must be considered when discussing the description of the technology described herein.

[0022] The headings (such as "Introduction" and "Summary of the Invention") and subheadings used herein are intended only for the general organization of the subject matter disclosed herein and are not intended to limit the disclosure of the technology or any aspect thereof. In particular, the subject matter disclosed in the "Introduction" may include new technology and may not constitute a record of prior art. The subject matter disclosed in the "Summary of the Invention" is not an exhaustive or complete disclosure of the entire scope of the technology or any embodiment thereof. The classification or discussion of materials for particular uses in a portion of this specification is for convenience, and it should not be inferred that when a material is used in any given composition, it must or can only function according to its classification herein.

[0023] The citation of references herein does not constitute an admission that these references are prior art or have any relevance to the patentability of the technology disclosed herein. The entire contents of all references cited in the "Implementation" section of this specification are incorporated herein by reference.

[0024] The description and specific examples, while indicating embodiments of the present technology, are for illustrative purposes only and are not intended to limit the scope of the present technology. Furthermore, reciting multiple embodiments having described features is not intended to exclude other embodiments having additional features, or other embodiments incorporating different combinations of the described features. Specific examples are provided to illustrate how to make and use devices and systems of the present technology and, unless expressly stated otherwise, are not intended to indicate that a given embodiment of the present technology has or has not been made or tested.

[0025] As used herein, the word "include" and its variations are intended to be non-limiting, such that the enumeration of items in a list does not exclude other similar items that may also be useful in the materials, compositions, apparatus, and methods of the present technology. Similarly, the terms "can" and "may" and their variations are intended to be non-limiting, such that recitation of an embodiment can or may include certain elements or features does not exclude other embodiments of the present technology that do not include those elements or features.

[0026] As used herein, "a" and "an" indicate the presence of "at least one" of an item; where possible, multiple items may be present. When applied to numerical values, "about" means that the calculation or measurement allows for some slight imprecision in the value (with some approach to the precision of the value; approximately or reasonably close to the value; roughly). If, for some reason, the imprecision provided by "about" is not understood in the art to have this ordinary meaning, then "about" as used herein at least indicates that there may be variations that may arise from ordinary methods of measuring or using such parameters. In addition, the disclosure of a range includes disclosure of all different values ​​and further subdivided ranges within the entire range.

[0027] It should be noted that the various embodiments of the present disclosure can be directly applied to a variety of agricultural or other soil working / earthmoving vehicles and / or implements, regardless of the type of implement, as the primary function of the implement does not affect the operation of the system. These embodiments can be installed in a permanent and fixed arrangement, or in a temporary and removable arrangement. Alternatively, the various components of the system described herein can be packaged into a single unit that can be portable and easily moved from one implement or vehicle to another, or can be manually carried and operated, for example, in conjunction with a soil core sampling device. The system can use soil disruption elements that form an integral part of the implement, or it can itself include soil disruption elements. For example, the latter arrangement may facilitate use of the system with implements that do not already include soil disruption tools, such as applicators or sprayers. The unit can be connected to certain systems of the vehicle or implement with which it is used, such as the vehicle's or implement's electrical system or any form of ISO or other communication bus to power the unit and connect it to other vehicle / implement components or to the vehicle's or implement's onboard GPS device.

[0028] While embodiments of the present disclosure may be described in the context of soil assessment to determine the appropriate dosage of soil amendments for increasing crop yields and / or to estimate expected yields, the present disclosure is not limited to use of the system in this context. Soil CO2 levels, alone or in combination with other substances present, can predict soil fertility, soil health, productivity, and other agronomic parameters. These factors, in turn, can allow for the calculation of additional parameters, such as more efficient planting populations in different areas of a field to achieve more efficient sowing yield performance.

[0029] However, the present disclosure encompasses the application of the system to any application where it is desirable to measure relevant properties of a soil region. Examples may include, but are not limited to, identifying areas of soil contamination caused by pollutants, determining the extent of such contamination to assess and / or maximize the effectiveness of necessary cleanup procedures, or identifying leaks from underground or above-ground chemical storage facilities, industrial facilities, or other potential sources. The various properties or soil substances that can be detected and measured may include, but are not limited to, acetaldehyde, acetic acid, acetone, acetonitrile, acetylene, acrylonitrile, ethanol, aldehydes, alkenes, alkynes, amines, ammonia, aromatic hydrocarbons, benzene, butadiene, butane, butanol, carbon dioxide, carbon monoxide, carboxylic acids, chlorine, chlorine dioxide, chlorine compounds, ethyl chloride, cyclohexane, decane, diethyl ether, dienes, diesel, esters, ethane, ethanol, ether, ethyl acetate, ethylamine, ethylene, ethylene oxide, formaldehyde, gasoline, helium, hexane, hydrogen, hydrogen sulfide, isoprene, jet fuel JP4, methane, methyl ethyl ketone, methyl methacrylate, naphthalene, nitric oxide, nitrogen dioxide, octane, oxygen, paraffin, gasoline, propane, propylene, styrene, sulfur dioxide, tetrahydrofuran, turpentine, volatile organic compounds (VOCs), vinyl acetate, vinyl compounds, white wine, xylem (ortho, meta, and para), relative humidity, and temperature. Various embodiments may also include a spectrophotometer, mass spectrometer, or similar device to facilitate these analyses.

[0030] Furthermore, embodiments of the present disclosure may be adapted to measure substances other than gases, such as the concentration of liquids, for example, by replacing the air movement device described herein with a suitable liquid pump to draw the liquid or soil / liquid mixture into the system for delivery to a suitable sensor. It is further contemplated within the scope of the present disclosure to use embodiments of the system to assess other properties of soil and the amount of air, liquid, or other substances entrained within the soil.

[0031] Figures 1 to 3 Various embodiments of a system 5 according to the present disclosure are schematically illustrated. If applicable, the system 5 can further be coordinated with the operation of soil breaking / work implements on an associated vehicle. In such cases, certain components of the system can be appropriately positioned relative to these implements to further facilitate operation of the system, as described in greater detail herein.

[0032] The specific nature of the associated implement is not critical to the operation of the system, and its use is not a requirement of the system. Although in one embodiment a cutting blade positioned behind the coulter may be used, other arrangements may be used. More particularly, the integration of the work implement with the air intake of the system is beneficial because operations for soil gas or other property measurements can be performed simultaneously with plowing or other soil working applications, saving time and money. The implement used can be any common soil working or earthmoving implement, such as, but not limited to, soil tillage implements (such as moldboards, reversible plows, chisel plows, disc plows, or submersible plows), planters, harvesting implements, fertilizer applicators and sprayers, tractors, bulldozers, backhoes, excavators, graders, scrapers, trenchers, or front-end loaders.

[0033] The system may include an air inlet 10 that is advantageously positioned to be placed within the soil environment being evaluated and to receive air from the soil. More particularly, the air inlet 10 is configured to facilitate rapid extraction of air from the soil so as to minimize intermixing of the air extracted from the soil with the atmosphere above the soil, as such intermixing could directly interfere with the accuracy of measurements taken by the system 5.

[0034] There are many practical challenges in extracting soil air. One of these challenges is the ability to limit the number of soil particles extracted along with the air sample. When system 5 draws in soil particles, particularly larger ones, there is an increased likelihood of damage to sensors used in system 5, as described below. Embodiments of the present disclosure address this challenge in several alternative ways. In one embodiment, the opening of the air inlet 12 can be circular, rectangular, or any other suitable cross-sectional shape, configured to have a cross-sectional area significantly larger than the inner diameter of the air inlet conduit 14, which forms a portion of the outlet of the air inlet 10. In a preferred embodiment, the ratio of the inner diameter of the air inlet 12 to the inner diameter of the air inlet conduit 14 is approximately 5:1, although other ratios may be employed without departing from the scope of the present disclosure. It has been discovered that employing an inner diameter of the air inlet 12 that is larger than the inner diameter of the air conduit 14 helps reduce the velocity of the air drawn into the air inlet 10. This reduced air velocity results in reduced forces and turbulence exerted on the soil, potentially reducing further soil damage and thereby increasing the amount of soil particles drawn into the air inlet 10.

[0035] Various embodiments of the system 5 can be provided with air inlet 12 having different configurations, such as a pipe segment, a nozzle, a fitting, and the like. Desirable characteristics of the air inlet 12 can include an open end having the cross-sectional dimension measurements described above and an opposite end configured to securely and sealingly mate with the air conduit 14 in a substantially airtight manner to facilitate efficient transfer of air collected from the soil to the system 5 for measurement.

[0036] The air duct 14 can include either rigid or flexible tubing or hoses that are substantially airtight or sufficiently air-impermeable to minimize air transmission through the walls of the air duct 14. The inner diameter of the air duct 14 can conform to the cross-sectional area ratios described above. The outer diameter of the air duct 14 can be essentially any size, but it should be understood that a particular application may require the outer dimensions of the duct 14 to facilitate installation. While flexible tubing is often used in the air duct 14 for ease of installation because it can be more easily routed through and / or around various obstructions, rigid tubing may offer advantages in durability and corresponding service life, particularly in system embodiments that are permanently installed in a particular vehicle or implement, although this may require a more complex installation process.

[0037] The air intake 10 may be associated with a soil working or breaking implement 16. The soil working / breaking implement 16 may be incorporated into the air intake 10 itself, or an existing implement, such as may be present on a tiller, planter, or cultivator, may be used by appropriately positioning the air intake 10 relative to the existing implement. The soil working / breaking implement 16 may be configured to create small rows or furrows through which the air intake 10 is arranged. In one embodiment, the soil working / breaking implement 16 may create rows or furrows that are approximately 2 inches to 4 inches deep, as rows or furrows of this depth provide adequate exposure of the air intake 10 to the soil while maintaining soil disturbance and achieving reasonable levels of airborne soil particles, although other embodiments may be employed measuring other soil depths. In a preferred embodiment, the air intake inlet 12 is positioned rearward of the soil working / breaking implement 16 relative to the direction of travel of the vehicle / implement. The air inlet 10 may also include a soil engagement sensor, such as but not limited to a whisker switch, proximity switch, or pressure switch, to allow the system 5 to determine when the air inlet is in the soil and when it is lifted out of the soil. This feature is particularly advantageous in conjunction with the data correction / calibration methods described herein.

[0038] In another embodiment, the soil working / breaking tool 16 may further include one or more spur teeth 18. The spur teeth are associated with the trailing side of the soil working / breaking tool 16. The spur teeth may include top spur teeth 18a located above the air inlet 12 and / or bottom spur teeth 18b located below the air inlet 12. The top spur teeth 18a, if present, prevent soil displaced by the leading edge of the soil working / breaking tool 16 from immediately falling back into the trench and onto or into the air inlet 12. The top spur teeth 18a may also act as a barrier that at least partially shields the air inlet 12 from the atmosphere. The bottom spur teeth 18b, if present, may help prevent the air inlet 12 from becoming clogged during initial contact with the soil and / or prevent contamination of the air inlet 12 by newly disturbed soil. The spur teeth 18 may be oriented horizontally or vertically.

[0039] A vacuum pump 20 or other fluid moving mechanism may also be provided in fluid communication with the air inlet 10. The vacuum pump 20 operates to draw air in through the air inlet 10. In various embodiments, the vacuum pump 20 may be connected to the air inlet 10 by an air inlet conduit 14. In an exemplary non-limiting embodiment, the vacuum pump 20 is a high suction diaphragm pump that produces a flow rate or suction capacity of approximately 8 L / min and a pressure range of approximately 500 to 8000 mmHG. Preferably, the vacuum pump 20 may be configured to maintain a high air velocity and positive pressure after the pump 20. In another embodiment, two pumps operating in series may be used instead of a single pump. Other pumps or other air moving devices may be used in alternative embodiments in accordance with the present disclosure.

[0040] Air drawn into system 5 by vacuum pump 20 through air inlet 10 is delivered to one or more sensors in fluid communication with these system components. If multiple sensors are provided, they can be connected in series or parallel within system 5. In one embodiment, the first such sensor is a CO2 sensor 30, which detects and measures the amount of CO2 present in the air drawn from the soil into system 5. CO2 sensor 30 is preferably calibrated to measure atmospheric CO2 in the range of 0 ppm to 10,000 ppm (0%-1%). The CO2 sensor can be a non-dispersive infrared sensor. An example of a suitable CO2 sensor is the K30 10,000 ppm CO2 sensor from CO2Meter.com. In some embodiments, CO2 sensor 30 can also be a combined CO2, temperature, and relative humidity sensor to measure additional soil properties. An example of such a sensor is the CozIR® 10,000 ppm CO2 + RH / T sensor from CO2Meter.com. Another example of such a sensor is the Grove SCD30 CO2, Temperature, and Humidity Sensor. In some embodiments, the CO2 sensor 30 can be paired with an O2 sensor or a combined O2 and temperature sensor 40. In a preferred implementation of this embodiment, the CO2 and O2 sensors 30, 40 are configured in series in the system 5, with the CO2 sensor 30 positioned before the O2 sensor 40.

[0041] In some embodiments, a mass air flow sensor 50 may be incorporated into the system 5, preferably located after the sensors 30 and / or 40 in the direction of flow. The mass air flow sensor 50 measures the flow of air through the system 5 and may trigger an alarm or other notification if the air flow drops below a predetermined threshold, which may indicate a blockage condition, for example, if the air intake or other components become contaminated with soil particles so that air can no longer flow freely therethrough, or if the vacuum pump 20 or other components in the system 5 malfunction, any of which may result in inaccurate or incapable measurements from the system 5.

[0042] As previously mentioned, soil particulate matter contamination of various components of system 5 presents a significant challenge. While the configuration of air inlet 10 described herein is intended to reduce contamination and clogging caused by soil particulate matter, some embodiments may further include an air filter 60 to specifically protect sensors 30 and / or 40, which are particularly susceptible to damage from such particulate matter, and also to specifically protect vacuum pump 20, as it is not possible to completely eliminate all such contamination in system 5 through any configuration of air inlet 10. Air filter 60 is preferably positioned in system 5 before vacuum pump 20 and sensors 30, 40 in the direction of airflow. In a preferred embodiment, air filter 60 is relatively thin, such as a 0.023µ filter. Another preferred version of this filter includes tubing barbs on its inlet and outlet sides to facilitate connection to system 5. Providing two air filters 60, preferably arranged in parallel within system 5, can aid in filtration of system 5. Using two filters in parallel can reduce air velocity losses across the filters compared to the efficiency loss of a single filter.

[0043] As will be appreciated by those skilled in the art, after a period of operation, the air filter 60 and possibly other system components will eventually become clogged or contaminated with soil particles. The system can simply be shut down and one or more air filters 60 and / or other system components manually removed, cleaned, or replaced. However, this requires the system to be shut down for an extended period of time, which, if necessary during operation, can be a significant impediment to effective use of the system. Therefore, in a preferred embodiment, the system 5 includes a subsystem configured to allow the system to self-clean or recover, thereby reducing system downtime and maintenance. In a preferred method of operation, the self-cleaning / recovery steps are performed when the equipment reaches the end of a row in the field and during the transition to the next row. Advantageously, this allows the system to perform these steps while the implement and air inlet 12 are lifted out of the soil and within a confined space, as well as during the continued movement of the implement and system 5, thereby minimizing any interruptions to the acquisition of soil gas measurements and / or the operation of the implement.

[0044] An air compressor 70 and / or a compressed air tank 80 may be provided in the system 5. In some embodiments, the air compressor 70 provides a source of compressed air. The compressed air generated by the air compressor 70 may be stored in the tank 80 or supplied directly to the remaining components of the system 5, as described below. In embodiments where the tank 80 is used, the air compressor 70 may be controlled to operate at a certain frequency and duration to maintain the amount of compressed air in the tank 80 at a desired threshold volume and pressure. A sensor associated with the tank 80 that monitors the pressure within the tank 80 may send a sensor signal to a controller, which in turn may activate the operation of the air compressor 70, such as the controller 110 described below. Alternatively, if the tank 80 is not used, the controller may activate the operation of the air compressor 70 each time a cleaning / restore cycle is initiated.

[0045] As described above, during normal operation of the system 5, air is drawn into the system 5 through the air intake 10 and the air filter 60 and into the CO2 30 and O2 40 or other sensors and the air flow sensor 50. During the cleaning / recovery cycle, air can flow in the opposite direction through the air filter 60 and out of the air intake 10 to push or blow contaminants out of these components. Therefore, it is an advantage to be able to control the direction of air flow through these components. In a preferred embodiment, this can be achieved by using a diverter valve 90, which is consistent with the vacuum pump 20, the air intake 10 and the filter 60, and is also in fluid communication with the compressed air source, whether it is a direct air compressor 70 or a compressed air storage tank 80. In one embodiment, the diverter valve 90 may include a three-way solenoid pneumatic valve 92. The solenoid valve 92 may have a normal position and an energized position, wherein the normal position allows air to flow from the air intake 10 and the filter 60 to the vacuum pump 20, while the energized position closes the air flow path between the vacuum pump 20 and the air intake 10 and the filter 60, and opens the air flow path from the compressed air source 70 and / or 80 to the air filter 60 and the air intake 10. In the energized position, compressed air may be pushed back through the air filter 60 and the air intake 10, thereby blowing debris and contaminants out of these components, thereby cleaning / restoring the filter 60 and the air intake 10.

[0046] In a preferred embodiment, the diverter valve 90 can be configured to be controlled by a controller 110 or another device. Specifically, in embodiments employing a three-way solenoid valve, the controller 110 or other device can supply current to the solenoid valve 92, causing it to switch from its normal position to its energized position. In the energized position, compressed air can flow from the compressed air source 70 / 80 to the filter 60 and the air inlet 10 to facilitate the cleaning / restoration cycle. When the cycle is complete, which can be determined based on readings from the air flow sensor 50 and / or a timer, the controller 110 or other device interrupts the flow of current to the solenoid valve 92, thereby returning it to its normal position, in which the vacuum pump 20 can draw air through the air inlet 10 and the filter 60. It should be noted that the aforementioned operation of the solenoid valve 92 can also be reversed, such that the normal position of the solenoid valve allows air to flow between the air inlet 10, the filter 60, and the compressed air source, while the energized position allows air to flow between the vacuum pump, the air inlet 10, and the filter 60. Further, the diverter valve 90 may be positioned elsewhere in the system 5 relative to the vacuum pump 20 , the CO 2 sensor 30 , the O 2 sensor 40 , and the mass air flow sensor 50 .

[0047] Controller 110 may reside with the other components of system 5 or be remotely located therefrom, in which case controller 110 may communicate with the other system components directly or through a communication network of an associated vehicle or implement.

[0048] In a particularly preferred embodiment, system 5 also includes a GPS unit 100. As system 5 moves around the site or other space being surveyed, GPS unit 100 monitors the global location of system 5 and / or the vehicle on which it is installed. In alternative embodiments, system 5 may utilize an existing GPS unit associated with an implement and / or vehicle. The connection between system 5 and the remote GPS unit may be direct or via an existing communication network associated with the implement and / or vehicle, such as an ISO or other communication bus.

[0049] The GPS unit 100 can communicate with the controller 110 and can transmit position data to the controller 110. Advantageously, this arrangement allows the controller 110 to reconcile readings from at least the CO 2 30 and O 2 40 or other sensors with the position data provided by the GPS unit 100. This reconciliation data allows the controller 110 or a separate computer to generate a Figure 4 8, the controller data can be downloaded to the computer during or after operation. Figure 4 The levels of CO2 and O2 or other gases at specific locations throughout a field are shown in the data graphs shown in Figure 8. These data graphs can provide more accurate information to indicate where CO2 levels are high within a field.

[0050] As described above, the controller 110 can communicate with various other components included in the system 5, such as the air compressor 70, the compressed air tank 80, the diverter valve 90 and / or sensors associated with the tank 80, the CO2 sensor 30, the O2 sensor 40, the air flow sensor 50, the vacuum pump 20 and the GPS unit 100, so as to control and coordinate the operation of these components as described above. Figure 3 An exemplary data flow / wiring diagram for an embodiment of the present disclosure is provided. The controller 110 may initiate data reading by directing power to the vacuum pump 20 to initiate airflow into the system 5. Simultaneously, it may activate and receive data from the various sensors 30, 40, 50, and also activate and receive data from the GPS unit 100.

[0051] In one particular aspect, the controller 110 can receive signals from the air flow sensor 50 to monitor for any reduction or interruption in the air flow through the system 5. In response to a reduction in air flow, the controller 110 can initiate a cleaning / recovery cycle by: (a) interrupting power to the vacuum pump 20 to suspend its operation, (b) sending power to the solenoid valve 92 (or interrupting power to the solenoid valve 92) to redirect air flow to a path connecting the air compressor 70 and / or compressed air storage tank 80 to the air filter 60 and the air intake 10, and (c) supplying power to the air compressor 70 to begin operation, thereby supplying compressed air to the air filter 60 and the air intake 10, if necessary at the time. Further, the controller 110 can monitor sensors associated with the compressed air storage tank 80 and control the operation of the air compressor 70 accordingly to maintain a desired pressure within the tank. Until the air flow sensor 50 again detects a decrease in air flow in the system, the controller 110 maintains the cleaning / recovery cycle for a predetermined amount of time, or upon receiving the best reading from the air flow sensor 50, before operating the diverter valve 90 to return the system 5 to its normal operating state. In an alternative embodiment, the vacuum pump 20 and the compressor 70 may operate continuously. In this case, the controller 110 will only activate the solenoid valve 92 to redirect the air flow in order to start and stop the cleaning / recovery cycle. This mode of operation can speed up the transition between normal operation and cleaning / recovery.

[0052] While the disclosed system is well-suited to addressing the technical problems described herein, it has been discovered that the accuracy of the system can be further improved by incorporating embodiments of data sampling and smoothing methods into the system's data collection and analysis logic. The described methods allow for better statistical fits to the collected data and better account for expected variability in measurement accuracy due to inevitable variations in sampling during system operation. More specifically, the methods can allow for the use of gas sensors, such as CO2 and O2 sensors, with less-than-ideal sensitivity and repeatability. For example, because a 20 ppm variation in the detection level of certain gases can be significant, a sensor with a repeatability of + / -50 ppm can produce measurement variations of up to 100 ppm, potentially yielding suboptimal results. In some embodiments, accuracy can be improved by using redundant sensors, as the readings from the redundant sensors are averaged to improve accuracy and / or provide a means of quality control of sensor performance. Furthermore, when the air intake 10 is raised to allow the vehicle to turn within the measurement field, the data points are significantly affected.

[0053] While the traditional method of fitting data points to a curve is to average the multiple data points together, it has been found that this method results in a significantly reduced accuracy of the data curve due to the center value being too flat, thereby eliminating valuable data. This is particularly true for the portion of the data associated with vehicle cornering, as the system is not in direct contact with the soil and is therefore taking readings from the atmosphere rather than soil gas.

[0054] Instead, it is preferred to calculate a polynomial curve from the collected data points to generate a polynomial output. The results produced by this method differ from those of conventional methods as follows Figure 4 、 Figure 5A and Figure 5B As shown, this also provides raw data points and confirms the example section where the two methods produce meaningfully different information. Figure 5A shows the data before correction, and Figure 5B The corrected data is shown. More specifically, it has been found that this method more accurately reflects the actual changes in gas concentration levels between samples. However, higher quality sensors relative to CO2 sensors are not necessarily required for polynomial averaging.

[0055] Figure 6A and Figure 6B shows the results of a second data correction step that may be incorporated into various aspects of the present disclosure, Figure 6A shows the data before correction, and Figure 6BCorrected data is obtained. It should be noted that concentration readings obtained by the system may experience some delay relative to the confirmation of the system's position as determined by the GPS device. This delay may be due to the time required for the gas sample to travel from the inlet to the sensor. This delay may cause data points to be skewed relative to the actual location where the sampling associated with a given data point occurred. According to this aspect, this delay can be determined and utilized to correct the data points so that their positional accuracy is maintained.

[0056] More specifically, the system identifies where the air intake is raised from the soil to allow the implement to rotate, and where it is lowered back into the soil. Furthermore, the system combines this information with the expected gas concentration levels present in the atmosphere (relative to the soil) to determine the amount of data point offset due to measurement delay, which in turn corresponds to the amount of offset that should be applied to the data points to more accurately reflect their relative positioning within the field. More specifically, the system determines the time period during which the air intake is out of the soil, drawing in atmospheric air rather than soil gas. The gas concentration levels obtained during this time period plus a subsequent period are averaged, and the period with the lowest average gas concentration represents the delay used in the system's calculations. This calculation results in the sensor reading being adjusted in response to the determined GPS position minus the determined time delay. Further, for example, when using a GPS unit on an implement or carrier unit, such as a tractor, combine, bulldozer, etc., the system can account for delays due to the positioning of the GPS unit 100 relative to the air intake 10, where the GPS unit 100 is not directly adjacent to the air intake 10 and may be several feet away from the air intake 10.

[0057] As a non-limiting example, if the air inlet is raised from the soil for 30 seconds, then the readings taken during that period after the inlet is raised are averaged. This averaging process lasts for at least 45 seconds. If the sensor operates instantaneously, the lowest average value will occur at approximately 15 seconds, the midpoint between the time the inlet is raised and lowered. However, if the lowest average value is measured 24 seconds after the inlet is raised, the sensor delay will be calculated as 24 seconds minus the control value of 15 seconds, resulting in a delay of 9 seconds.

[0058] exist Figure 6A In the figure, the vertical black lines indicate the approximate points at which the implement raises and lowers the air intake to accommodate the turn. The data points shown represent the corresponding measured delays. Once the above correction steps are taken, the adjusted data graph will more accurately reflect the positioning of the data points relative to the raising and lowering of the air intake.

[0059] Figure 7A and Figure 7B An embodiment of a method of calibrating sensor data of a system is shown, wherein Figure 7A shows the data before calibration, while Figure 7BPost-calibration data is shown. This step again uses the expected atmospheric gas concentration and the determination of when to lift the air inlet out of the soil, thus employing atmospheric gas rather than soil gas. In this case, it combines this information with measurements of the velocity of air passing through the system. More specifically, the system calculates when the measured concentration should reach the expected atmospheric gas concentration based on the air velocity in the system. The difference between the expected time to reach the expected gas concentration and the actual time to flush the soil gas level from the system to reach the expected atmospheric gas concentration represents the correction factor that the system then uses to calibrate the sensor readings. Similarly, the first of the two data graphs represents a data point acquired without this calibration step, while the second shows the same data point acquired after the calibration step.

[0060] Figure 8A and Figure 8B A second embodiment of the sensor data for the calibration system is shown, wherein Figure 8A shows the data before calibration, while Figure 8B Calibrated data is shown. The illustrated embodiment uses a calibration procedure that relies on O2 levels. However, it should be noted that other gas levels, such as, but not limited to, CO2 or N2, can also be measured and used in this calibration method. Measurements of some soil gases, such as O2, tend to fluctuate gradually, especially when using less expensive sensors, deviating from the actual concentration level relative to the sample location and ignoring subtle variations in the actual soil concentration level. More accurate sensors that are less susceptible to this effect can be used, but at a higher cost. The system also determines the point at which the air inlet is raised from the soil, from which it begins sampling atmospheric rather than soil gas levels. During the period between the raising and then lowering of the air inlet, a linear change in the measured gas level can be identified, first increasing and then decreasing. The system then uses this information to calibrate the readings taken by the sensor during the remainder of the data graph. Similarly, the first of the two data graphs represents a data point taken without this calibration step, and the second represents the same data point taken after the calibration step.

[0061] With respect to the calibration embodiments described above, it should be noted that where expected atmospheric concentrations are used, an air sample containing the expected gas concentration, such as a container containing such a sample, may be introduced directly into the system rather than taking readings from the atmosphere.

[0062] Typically, yield data is recorded and analyzed as a series of points. These points include latitude and longitude to identify the geographic location and associate that location with a single yield value. However, using these points often oversimplifies yield data.

[0063] Conversely, polygons can be used with measured yield data to provide higher resolution mapping of the data. The associated polygons represent the approximate footprint of the soil from which the measured yield data was obtained.

[0064] Polygon-based yield data is calculated based on the vehicle's speed, the total width of the implement used on the vehicle—for example, the grain header, the feeder box width (the width of the combine's inlet throat), the header's inward speed, and the previously harvested area. These metrics determine the area and shape of the associated polygon, so these features may vary. For example, if vehicle speed increases, the arc in the polygon increases. Decreasing speed, on the other hand, results in a flatter arc.

[0065] While in a preferred embodiment all of the above-described correction and calibration steps are employed in the system, it is within the scope of the present disclosure that these steps may be employed individually or in combination with one another.

[0066] It should also be noted that the systems and methods of the present disclosure, while described in the context of possible agricultural uses, are also applicable to other applications, for which appropriate gas sensors can be used to determine soil gas levels, including levels of various types of gases other than CO2 or O2. In the described embodiments, CO2 or other gas concentrations can be used to calculate soil fertility, yield expectations, and / or recommended application rates for nitrogen, phosphorus, or other fertilizers. This data can further allow for more efficient seeding and planting populations in different regions to maximize seeding and yield efficiency. Further, the systems and methods described herein can be used for soil testing at various soil depths by making minor modifications to the air inlet and using appropriate tools to position the air inlet at the desired soil depth.

[0067] The preferred embodiments of the present invention have been described above to explain the principles of the invention and its practical application, thereby enabling others skilled in the art to utilize the invention in the best manner known to the inventors. However, since various modifications may be made to the structures and methods described and illustrated herein without departing from the scope of the present invention, it is intended that all matter contained in the foregoing description or shown in the accompanying drawings be interpreted as illustrative and not restrictive. Therefore, the breadth and scope of the present invention should not be limited by the above-described exemplary embodiments, but should be defined only in accordance with the appended claims and their equivalents.

Claims

1. A system for determining soil properties, comprising: an air inlet mounted on a soil working implement of an associated vehicle and in fluid communication with a vacuum pump mounted on the associated vehicle, the air inlet and the vacuum pump configured to continuously draw soil gas from the soil through the air inlet during movement of the associated vehicle; at least one gas sensor in fluid communication with the air intake and operable to continuously receive soil gas from the air intake during movement of the associated vehicle and to measure a gas concentration level in the soil gas received from the air intake; a GPS unit operable to confirm the location of the system during movement of the associated vehicle and while the at least one gas sensor receives soil gas from the air intake and measures gas concentration levels; as well as A controller is in communication with the at least one gas sensor and the GPS unit and is configured to map measurements from the at least one gas sensor with respect to a system location determined by the GPS unit.

2. The system for determining soil properties of claim 1, wherein the at least one gas sensor is at least one of a CO2 sensor, an O2 sensor, or an NH4 sensor.

3. The system for determining soil properties of claim 1 , further comprising at least a second gas sensor.

4. The system for determining soil properties of claim 1 , further comprising at least one of a spectrophotometer or a mass spectrometer.

5. The system for determining soil properties of claim 1, further comprising a temperature sensor.

6. The system for determining soil properties of claim 1 , further comprising a relative humidity sensor.

7. The system for determining soil properties of claim 1 , further comprising a cleaning / recharging subsystem, the cleaning / recharging subsystem comprising: a pressurized air source; A switchable valve is in fluid communication with the pressurized air source and the air inlet, the switchable valve being operable to selectively fluidly connect the pressurized air source with the air inlet.

8. A method for determining soil properties, comprising the steps of: continuously extracting soil gas from the soil through an air intake with a vacuum pump during movement of an associated vehicle having a soil working implement, the air intake being mounted on the soil working implement; continuously transmitting the soil gas to at least one gas sensor during movement of the associated vehicle; measuring a gas concentration in the soil gas with the at least one gas sensor; transmitting the measured gas concentration to a controller; determining a position of the air intake using a GPS unit during movement of the air intake with the associated vehicle; transmitting the position to the controller; as well as The measured gas concentration is mapped using the location.

9. The method for determining soil properties according to claim 8, further comprising the steps of: Repeating the steps of measuring the gas concentration, determining the location, transmitting the location to the controller, and mapping the measured gas concentration using the location to generate a series of gas concentration data points at geographical locations; as well as A polynomial curve is calculated from the gas concentration data points at the series of geographic locations to produce a polynomial output.

10. The method for determining soil properties according to claim 8, further comprising the steps of: Repeating the steps of measuring the gas concentration, determining the location, transmitting the location to the controller, and mapping the measured gas concentration using the location to generate a series of gas concentration data points at geographical locations; determining a first position and a second position, wherein the air inlet is raised out of the soil at the first position and the air inlet is lowered back into the soil at the second position; measuring a first gas concentration level at the first location and a second gas concentration level at the second location; comparing the expected gas concentration level to the first measured gas concentration level and the second measured gas concentration level; and The series of gas concentration data points at geographical locations are adjusted based on a difference between the expected gas concentration level and the measured gas concentration level.

11. The method for determining soil properties according to claim 8, further comprising the steps of: Repeating the steps of measuring the gas concentration, determining the location, transmitting the location to the controller, and mapping the measured gas concentration using the location to generate a series of gas concentration data points at geographical locations; determining a first position and a second position, wherein the air inlet is raised out of the soil at the first position and the air inlet is lowered back into the soil at the second position; measuring a velocity of gas from the gas inlet to the at least one gas sensor; determining an expected time period for the measured gas concentration to reach an expected gas concentration level from the first position and the second position and the measured gas velocity; measuring an actual time period for the measured gas concentration to reach the expected concentration level; and The series of gas concentration data points at geographical locations are adjusted based on a difference between the expected time period and the actual time period for the measured gas concentration to reach the expected concentration level.

12. The method for determining soil properties according to claim 8, further comprising the steps of: Repeating the steps of measuring the gas concentration, determining the location, transmitting the location to the controller, and mapping the measured gas concentration using the location to generate a series of gas concentration data points at geographical locations; as well as determining a first position and a second position, wherein the air inlet is raised out of the soil at the first position and the air inlet is lowered back into the soil at the second position; determining a first measured gas concentration at the first location and a second measured gas concentration at the second location; measuring a change between the first measured gas concentration and the second measured gas concentration; and The series of gas concentration data points at geographical locations are adjusted based on a measured change between the first measured gas concentration and the second measured gas concentration.

13. A method for determining soil properties, comprising the steps of: A system for determining soil properties during movement of an associated vehicle is provided, the system comprising: an air inlet mounted on a soil working implement of an associated vehicle and in fluid communication with a vacuum pump mounted on the associated vehicle, the air inlet and the vacuum pump configured to continuously draw soil gas from the soil through the air inlet during movement of the associated vehicle; at least one gas sensor in fluid communication with the air intake and operable to continuously receive soil gas from the air intake during movement of the associated vehicle and to measure a gas concentration level in the soil gas received from the air intake; a GPS unit operable to confirm the location of the system during movement of the associated vehicle and while the at least one gas sensor receives soil gas from the air intake and measures gas concentration levels; and a controller in communication with the at least one gas sensor and the GPS unit and configured to map measurements from the at least one gas sensor with respect to a system location determined by the GPS unit; continuously extracting soil gas from the soil through the air intake while the associated vehicle is moving; and transmitting the soil gas to the at least one gas sensor while the associated vehicle is moving. measuring a gas concentration in the soil gas with the at least one gas sensor; transmitting the measured gas concentration to the controller; determining a position of the air intake with the GPS unit during movement of the air intake with the associated vehicle; transmitting the position to the controller; and The measured gas concentration is mapped using the location.

14. The method for determining soil properties according to claim 13, further comprising the steps of: A cleaning / refilling subsystem is provided, comprising: a pressurized air source; and a switchable valve in fluid communication with the pressurized air source and the air inlet, the switchable valve being operable to selectively fluidly connect the pressurized air source with the air inlet.

Images