Soil constituent sensor and precision agrichemical delivery system and method

• US 6,484,652 B1
• Filed: 10/30/2000
• Issued: 11/26/2002
• Est. Priority Date: 07/22/1991
• Status: Expired due to Fees

• Current Assignee: Cross Technologies Incorporated
• Original Assignee: Cross Technologies Incorporated
• Inventors: Colburn, John W. Jr.
• Primary Examiner(s): BATSON, VICTOR D
• Application Number:
  US09/699,795
• Time in Patent Office: 757 Days
• Field of Search: 111/118, 111/200, 111/900, 111/903, 111/904, 111/121, 172/1, 172/2, 47/13, 73/73, 737/63, 175/50, 204/400
• US Class Current: 111/118
• CPC Class Codes: A01B 79/005 Precision agriculture
• CPC Class Codes: A01C 21/007 Determining fertilization requirements
• CPC Class Codes: A01C 23/007 Metering or regulating systems
• CPC Class Codes: A01C 23/02 Special arrangements for delivering the liquid directly into the soil
• CPC Class Codes: A01M 7/0089 Regulating or controlling systems the delivery being related to the movement of a vehicle B05B9/06
• CPC Class Codes: G01N 27/043 of a granular material
• CPC Class Codes: G01N 33/24 Earth materials G01N33/42 takes precedence
• CPC Class Codes: Y10S 111/903 Monitor

Abstract

A real time soil constituent sensor and precision agricultural chemical delivery system may measure simple in situ soil constituents without the aid of externally applied solvents, or such solvents may be utilized intermittently to calibrate the measurements for greater accuracy. A real time complex in situ soil resistivity sensor and prescription agricultural chemical delivery system includes a plurality of ground-engaging tools in association with individual soil electrode arrays which measure complex solute and matrix resistivity levels. Conventional engaging tools may serve as electrodes for impressing a voltage source and serve as a current sink for the purposes of determining complex resistivity values and components thereof in in situ soils. Alternatively, local resistivity measurements in a single tool can also be employed for separation of resistivity cotributions of the soil solute and the matrix. For calibration, to enhance the accuracy of in situ measurements of matrix resistivity, a plurality of reference fluids of known conductivity are periodically injected at the interface between electrodes on a single tool and the in situ soil. A real-time soil solute and matrix sensor and controller senses and separates the resistivity contributions of the solute and matrix and compares these components against target levels or schedules and adjusts a servo-controlled delivery system to apply the appropriate amount of agricultural chemical substantially in the location from which a calibrated complex soil resistivity measurement was taken.

Claims

1. A method for sensing substantially instantaneously at least one parameter of a soil while traversing a field of said soil, comprising the steps of:

penetrating the soil of a first soil sample while traversing said sample, and

pulsing said sample with a voltage differential or current pulse across said sample, and determining by transient analysis a parameter of said sample.

2. The method of claim 1, comprising the additional step of:

determining a constituent of said soil related to the parameter determined while traversing said sample.

3. The method of claim 2, wherein said constituent of said soil sample and a spatial location of said soil sample are recorded.

4. The method of claim 3, further comprising the step of

determining a prescription spatial treatment to be applied to said soil.

5. The method of claim 4, wherein said determined prescription spatial treatment and said spatial location are recorded.

6. The method of claim 4, further comprising the step of

calibrating said prescription spatial treatment to be applied with means for relating spatial crop yield or quality to spatial constituents.

7. The method of claim 4, further comprising a variable rate treatment step of

applying said spatial treatment to substantially said spatial location of said soil sample.

8. The method of claim 1, wherein the soil parameter determined is one of the parameters of soil conductivity, soil solution conductivity, soil particle conductivity or soil permitivity.

9. The method of claim 1, wherein said parameter of said soil sample and a spatial location of said soil sample are recorded.

10. A method for sensing, at least one parameter of a soil while traversing a field containing said soil, comprising the steps of

penetrating the soil of a soil sample and sub-sample of said sample while traversing said sample,

providing a current or voltage across said sample while traversing said sample, and

determining a parameter of said soil.

11. The method of claim 10, wherein said determined parameter is one of the parameters of soil conductivity, soil solution conductivity, soil particle conductivity or soil permittivity.

12. The method of claim 10, wherein said current or voltage comprises an alternating current excitation wavefrom.

13. A method for sensing at least one parameter of a soil while traversing a field containing said soil, comprising the steps of:

penetrating the soil of a soil sample and sub-sample of said sample while traversing said sample,

providing a current or voltage across said sample,

determining a parameter of said soil, and

recording said parameter of said soil sample and a spatial location of said sample.

14. The method of claim 13, wherein said penetrating step is accomplished by a radial spoke probe of a rotatable wheel means.

15. The method of claim 13, further comprising the step of

forming a four-electrode array for measuring potential across any pair of electrodes of said array.

16. The method of claim 13, wherein said soil sample is coupled by a second pair of insulated and electrically isolated electrodes connected to potential measuring means.

17. The method of claim 16, further comprising the step of

enhancing said coupling by kerf closing means.

18. The method of claim 17, wherein said kerf closing means comprises a closing wheel or penetration depth hub.

19. The method of claim 16, wherein said electrodes comprise coulters aligned substantially laterally to each other.

20. The method of claim 19, wherein said second pair of coulter electrodes is arranged between said first pair of coulter electrodes.

21. The method of claim 13, further comprising the step of

determining the spatial constituent of said soil related to said spatial parameter determined while traversing said soil.

22. The method of claim 21, wherein said spatial constituent determined is any of the constituents of nitrate, calcium, potassium, topsoil depth, water content, organic matter, cation exchange capacity, clay content, texture or soil type.

23. The method of claim 21, wherein said spatial constituent of said soil sample and a spatial location of said soil are recorded.

24. The method of claim 21, wherein said determination of said constituent comprises calibration information referenced by spatial location.

25. The method of claim 21, further comprising the step of

determining a prescription treatment to be applied to said soil.

26. The method of claim 25, further comprising the step of

recording said determined prescription treatment and a spatial location for said soil.

27. The method of claim 26, further comprising the step of

calibrating said prescription spatial treatment to be applied with means for relating spatial crop yield or quality to spatial parameters.

28. The method of claim 27, further comprising a variable rate treatment of

applying said spatial treatment to substantially said spatial location of said soil sample.

29. The method of claim 28, wherein said spatial treatment to be applied is any of the treatments of anhydrous ammonia, nitrogen in solution, manure, starter fertilizer, lime, potassium fertilizer, phosphate fertilizer or herbicide.