Farm vehicle autopilot with automatic calibration, tuning and diagnostics
View Patent ↗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.
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.