Farm vehicle autopilot with automatic calibration, tuning and diagnostics

• US 9,454,153 B2
• Filed: 11/24/2014
• Issued: 09/27/2016
• Est. Priority Date: 11/24/2014
• Status: Active Grant

• Current Assignee: Trimble Navigation Limited (Trimble Inc.)
• Original Assignee: Trimble Navigation Limited (Trimble Inc.)
• Inventors: Sights, Brandon M, Peake, John W
• Primary Examiner(s): MELTON, TODD M
• Application Number:
  US14/551,447
• Publication Number:
  US 20160147225A1
• Time in Patent Office: 673 Days
• US Class Current: 1/1
• CPC Class Codes: A01B 69/00 Steering of agricultural machines or implements; Guiding agricultural machines or implements on a desired track
• CPC Class Codes: A01B 69/008 automatic
• CPC Class Codes: G01S 19/13 Receivers
• CPC Class Codes: G05D 1/0088 characterized by the autonomous decision making process, e.g. artificial intelligence, predefined behaviours using knowledge based models G06N5/00
• CPC Class Codes: G05D 1/0221 involving a learning process
• CPC Class Codes: G05D 1/027 comprising intertial navigation means, e.g. azimuth detector inertial navigation G01C21/16; inertial navigation combined with non-inertial navigation instruments G01C21/165
• CPC Class Codes: G05D 1/0278 using satellite positioning signals, e.g. GPS
• CPC Class Codes: Y02A 40/10 in agriculture

Abstract

Automatic calibration, tuning and diagnostics improve precision farming by helping farmers obtain best performance from their autopilot-guided vehicles. Automatic calibration procedures that cannot be accurately performed by human drivers, automatic autopilot tuning, and simplified diagnostics are all parts of an advanced farm vehicle autopilot system.

Claims

1. A farm vehicle autopilot comprising:

a global navigational satellite system (GNSS) sensor and an inertial measurement unit (IMU) sensor in communication with a microprocessor and memory, wherein the microprocessor and memory are configured to;

(1) receive steering angle data from a steering angle sensor, (2) send steering angle commands to a steering angle actuator, and (3) perform automatic autopilot calibration by guiding a farm vehicle through a calibration maneuver and measuring vehicle response characteristics during the calibration maneuver with the GNSS and IMU sensors.

2. The farm vehicle autopilot of claim 1 wherein the microprocessor and memory are further configured to:

(4) perform automatic tuning of autopilot settings.

3. The farm vehicle autopilot of claim 1 wherein the microprocessor and memory are further configured to:

(4) perform automatic diagnostics of vehicle performance under autopilot control.

4. The farm vehicle autopilot of claim 3 wherein the automatic diagnostics include computing a performance grade to summarize calibration and/or tuning data.

5. The farm vehicle autopilot of claim 3 wherein the automatic diagnostics include reporting vehicle component abnormalities.

6. The farm vehicle autopilot of claim 3 wherein the automatic diagnostics are based on a fuzzy logic reasoner comprising degree-of-membership functions and fuzzy associative memory rules.

7. The farm vehicle autopilot of claim 3 wherein the automatic diagnostics are based on performance grading rules including weighted sums of vehicle characteristic data.

8. The farm vehicle autopilot of claim 3 further comprising an I/O component that permits the microprocessor and memory to communicate with a database, and wherein the microprocessor and memory are further configured to:

(5) obtain vehicle characteristics from the database and send vehicle characteristics to the database.

9. The farm vehicle autopilot of claim 1 wherein the vehicle response characteristics include steering angle rate:

dead zone, linear region or saturated region.

10. The farm vehicle autopilot of claim 1 wherein the vehicle response characteristics include steering angle:

delay time, rise time, settling time, overshoot or steady-state error.

11. The farm vehicle autopilot of claim 1 wherein the microprocessor and memory are further configured to:

(4) send vehicle speed commands to a vehicle speed actuator.

12. The farm vehicle autopilot of claim 1 wherein the calibration maneuver is completed within a pre-defined geographic area.

13. A method for farm vehicle autopilot calibration, tuning and diagnostics, the method comprising:

a microprocessor and memory in a farm vehicle autopilot;

receiving steering angle data from a steering angle sensor;

sending steering angle commands to a steering angle actuator;

guiding a farm vehicle through a calibration maneuver and measuring vehicle response characteristics during the calibration maneuver with GNSS and IMU sensors;

tuning autopilot settings according to a tuning algorithm;

computing a performance grade to summarize calibration and tuning data;

reporting vehicle component abnormalities; and

,

sending vehicle characteristics to, or receiving vehicle characteristics from, a database.

14. The method of claim 13, the sending or receiving performed via a cellular data network.

15. The method of claim 13 further comprising the microprocessor and memory sending vehicle speed commands to a vehicle speed actuator.

16. The method of claim 13, the computing a performance grade comprising fuzzy logic operations.