Crop feeler system and method

• US 9,066,463 B2
• Filed: 10/02/2012
• Issued: 06/30/2015
• Est. Priority Date: 10/02/2012
• Status: Active Grant

• Current Assignee: Trimble Navigation Limited (Trimble Inc.)
• Original Assignee: Trimble Navigation Limited (Trimble Inc.)
• Inventors: Lange, Arthur F.
• Primary Examiner(s): Beaulieu, Yonel
• Assistant Examiner(s): Hilgendorf, Dale W
• Application Number:
  US13/633,757
• Publication Number:
  US 20140095010A1
• Time in Patent Office: 1,001 Days
• Field of Search: 701/23, 701/26, 701/50, 701/301
• US Class Current: 1/1
• CPC Class Codes: A01B 69/008 automatic
• CPC Class Codes: A01D 41/1278 for automatic steering
• CPC Class Codes: B62D 6/001 the torque NOT being among the input parameters
• CPC Class Codes: G01S 13/931 of land vehicles
• CPC Class Codes: G01S 2013/9318 Controlling the steering
• CPC Class Codes: G01S 2013/93271 in the front of the vehicles
• CPC Class Codes: G01S 2013/93275 in the bumper area
• CPC Class Codes: G05D 1/0227 using mechanical sensing means, e.g. for sensing treated area
• CPC Class Codes: G05D 1/0259 using magnetic or electromagnetic means

Abstract

In some embodiments, a crop feeler system automatically executes a navigational task based on a proximity of a vehicle to an obstacle. The crop feeler system includes a hub attached to the vehicle. Inside the hub are two oscillating circuits each having an oscillating frequency. A member is coupled to the hub. Two inductive elements are positioned within the member so that, when the obstacle comes into contact with the member, at least one of the inductive elements moves closer to at least one of the oscillating circuits and alters the oscillating frequency of that oscillating circuit. A navigation sensor measures the oscillating frequency of the oscillating circuit, identifies a navigational task using the oscillating frequency of the oscillating circuit, and executes the navigational task.

Claims

1. A system for automatically executing a navigational task based on a proximity of a vehicle to an obstacle, the system comprising:

a hub attached to the vehicle, the hub including an oscillating circuit having an oscillating frequency;

a member coupled to the hub, the member including an inductive element adapted to alter the oscillating frequency commensurate with its proximity to the oscillating circuit; and

a navigation sensor adapted to;

determine the oscillating frequency of the oscillating circuit; and

identify a navigational task using a set of calibration data and the oscillating frequency of the oscillating circuit.

2. The system of claim 1, wherein the member is a flexible wand adapted to flex when the obstacle comes into contact with the flexible wand.

3. The system of claim 1, wherein the navigation sensor is adapted to execute the navigational task or transmit instructions to execute the navigational task.

4. The system of claim 1, wherein the member is adapted to decrease the oscillating frequency of the oscillating circuit by moving the inductive element closer to the oscillating circuit when the member comes into contact with the obstacle.

5. The system of claim 1, wherein the oscillating circuit includes an inductor and wherein the inductive element is a manganese-zinc-based ferrite core or other high permeability ferrite material.

6. The system of claim 1, wherein the navigation sensor is adapted to identify the navigational task by applying a displacement curve to a series of frequency measurements for the oscillating circuit.

7. The system of claim 6, wherein navigation sensor is adapted to assign less weight to outlying frequency measurements in the series of frequency measurements.

8. The system of claim 6, wherein the navigation sensor is adapted to assign more weight to outlying frequency measurements in the series of frequency measurements.

9. The system of claim 8, wherein the navigation sensor is adapted to determine a plurality of oscillating frequencies of the first and second oscillating circuits and to identify the navigational task using the plurality of oscillating frequencies.

10. The system of claim 9, wherein the navigation sensor is adapted to identify the navigational task by comparing oscillating frequencies from the first oscillating circuit and the second oscillating circuit.

11. The system of claim 1, wherein the oscillating circuit is a first oscillating circuit having a first oscillating frequency and the inductive element is a first inductive element, and wherein

the hub includes a second oscillating circuit having a second oscillating frequency;

the system includes a second inductive element adapted to alter the second oscillating frequency commensurate with its proximity to the second oscillating circuit; and

the navigation sensor is adapted to

determine the second oscillating frequency of the second oscillating circuit; and

identify the navigational task using the second oscillating frequency of the second oscillating circuit and the first oscillating frequency of the first oscillating circuit.

12. A method for navigating a vehicle with respect to an obstacle, the method comprising:

measuring a first oscillating frequency of a first oscillating circuit attached to the vehicle, the first oscillating frequency commensurate with a proximity of a first inductive element in a flexible member to the first oscillating circuit;

measuring a second oscillating frequency of a second oscillating circuit attached to a vehicle, the second oscillating frequency commensurate with a proximity of a second inductive element in the flexible member to the second oscillating circuit;

determining a navigational task using a set of calibration data, the first oscillating frequency and the second oscillating frequency; and

executing the navigational task to navigate the vehicle.

13. The method of claim 12, wherein determining the navigational task using the first oscillating frequency and the second oscillating frequency includes using calibration data that has been normalized based on the oscillating frequencies of the first and second oscillating circuits when the first and second inductive elements are at initial proximities to the first and second oscillating circuits.

14. The method of claim 12, wherein determining the navigational task using the first oscillating frequency and the second oscillating frequency includes using calibration data that has been normalized based at least in part on temperatures of the first and second oscillating circuits.

15. The method of claim 12, wherein measuring the first oscillating frequency and measuring the second oscillating frequency includes measuring a plurality of oscillating frequencies of the first and second oscillating circuits and wherein determining the navigational task includes using an ensemble technique to process the plurality of oscillating frequencies.

16. The method of claim 12, wherein measuring the first oscillating frequency and measuring the second oscillating frequency includes measuring a plurality of oscillating frequencies of the first and second oscillating circuits and wherein determining the navigational task includes fitting a curve to the plurality of oscillating frequencies to identify a relative position of crop rows with respect to a vehicle.

17. The method of claim 12, further comprising resetting a navigation sensor that is adapted to execute the step of determining the navigational task using the first oscillating frequency and the second oscillating frequency, wherein resetting the navigation sensor includes setting measurements of the first and second oscillating frequencies as indicative of a desired relative location of a vehicle with respect to one or more crop rows.

18. A navigation sensor comprising:

an inductive element adapted to alter the oscillating frequency commensurate with its proximity to an oscillating circuit;

a frequency analyzer adapted to measure oscillating frequencies of the oscillating circuit and determine a course adjustment for the vehicle using a set of calibration data stored in a memory and the oscillating frequencies of the oscillating circuit; and

a directional adjuster adapted to automatically execute the course adjustment for the vehicle.

19. The navigation sensor of claim 18, wherein the oscillating circuit is a first oscillating circuit and the oscillating frequencies are a first set of oscillating frequencies, and wherein the frequency analyzer is further adapted to measure a second set of oscillating frequencies of a second oscillating circuit.

20. The navigation sensor of claim 19, wherein the frequency analyzer is adapted to determine the course adjustment using the set of calibration data, the first set of oscillating frequencies, and the second set of oscillating frequencies.