초록

Predictive tractor path adjustments improve implement tracking performance by enabling agricultural autopilots to anticipate the effect of curves, slopes, changing soil conditions and other influences.

대표청구항 ▼

1. A method for agricultural implement curve tracking comprising: providing a desired path for an implement, the path represented by a set of implement path points and having a Cartesian slope at each, the implement characterized by a length, L;constructing a tractor path represented by a set of tra

1. A method for agricultural implement curve tracking comprising: providing a desired path for an implement, the path represented by a set of implement path points and having a Cartesian slope at each, the implement characterized by a length, L;constructing a tractor path represented by a set of tractor path points, each one determined by length, L, and the Cartesian slope of a corresponding point on the desired implement path; and,guiding a tractor along the tractor path as it pulls the implement. 2. The method of claim 1 further comprising: determining the topography of terrain that the desired implement path traverses; and,adjusting the tractor path uphill by an amount that is a function of L and the uphill slope of the terrain. 3. The method of claim 1 further comprising: monitoring implement position; and,using feedback control to correct for tracking errors. 4. The method of claim 3, the monitoring performed using a GNSS receiver. 5. The method of claim 3, the monitoring performed using a GNSS receiver and an inertial measurement unit. 6. A method for agricultural implement curve tracking comprising: providing a desired path for an implement characterized by a length, L, the desired path represented by a set of implement path points and having a Cartesian slope at each;constructing a hitch path for a hitch characterized by a length, H, the hitch path represented by a set of hitch path points, each one determined by length, L, and the Cartesian slope of a corresponding point on the desired implement path, the hitch path having a radius of curvature at each hitch path point;constructing a tractor path represented by a set of tractor path points, each one determined by length, H, and the radius of curvature at a corresponding point on the hitch path; and,guiding a tractor along the tractor path as it pulls the implement via the hitch. 7. The method of claim 6 further comprising: determining the topography of terrain that the desired implement path traverses; and,adjusting the tractor path uphill by an amount that is a function of L and the uphill slope of the terrain. 8. The method of claim 6 further comprising: monitoring implement position; and,using feedback control to correct for tracking errors. 9. The method of claim 8, the monitoring performed using a GNSS receiver. 10. The method of claim 8, the monitoring performed using a GNSS receiver and an inertial measurement unit. 11. A method for fixed agricultural implement curve tracking comprising: providing a desired path for a fixed implement characterized by a length H, the implement path represented by a set of implement path points, the implement path having a radius of curvature at each implement path point;constructing a tractor path represented by a set of tractor path points, each one determined by length, H, and the radius of curvature at a corresponding point on the implement path; and,guiding a tractor along the tractor path. 12. The method of claim 11 further comprising: determining the topography of terrain that the desired implement path traverses; and,adjusting the tractor path uphill by an amount that is a function of H and the uphill slope of the terrain. 13. The method of claim 11 further comprising: monitoring implement position; and,using feedback control to correct for tracking errors. 14. The method of claim 13, the monitoring performed using a GNSS receiver. 15. The method of claim 13, the monitoring performed using a GNSS receiver and an inertial measurement unit. 16. A method for agricultural implement tracking on hills comprising: providing a desired path for an implement, the path represented by a set of implement path points, the implement characterized by a length, L;constructing a tractor path represented by a set of tractor path points, each one determined by adjusting a corresponding implement path point uphill by an amount that is a function of L and the uphill slope of the terrain; and,guiding a tractor along the tractor path as it pulls the implement. 17. A system for guiding an agricultural implement comprising: tractor position and speed sensors for sending tractor position and speed information to an agricultural autopilot;implement position and speed sensors for sending implement position and speed information to the autopilot; and,actuators for adjusting tractor steering angle in response to autopilot commands;wherein,the implement is characterized by a length, L; and,the autopilot:a) comprises a memory that stores an implement path that is represented by a set of implement path points and has a Cartesian slope at each;b) calculates a tractor path, each point of which is determined by length, L, and the Cartesian slope of a corresponding point on the implement path;c) guides the tractor along the tractor path using the tractor position and speed information; and,d) maintains the implement on the implement path using the implement position and speed information. 18. The system of claim 17 wherein the tractor position and speed sensors and the implement position and speed sensors are based on GNSS receivers. 19. The system of claim 17 wherein the autopilot memory further stores a terrain map and the autopilot further adjusts the tractor path uphill by an amount that is a function of L and the uphill slope of the terrain. 20. A system for guiding an agricultural implement comprising: tractor position and speed sensors for sending tractor position and speed information to an agricultural autopilot;implement position and speed sensors for sending implement position and speed information to the autopilot; and,actuators for adjusting tractor steering angle in response to autopilot commands;wherein,the implement is characterized by a length, L, and is connected to a tractor by a hitch of length, H; and,the autopilot:a) comprises a memory that stores an implement path that is represented by a set of implement path points and has a Cartesian slope at each;b) calculates a hitch path, each point of which is determined by length, L, and the Cartesian slope of a corresponding point on the implement path, the hitch path having a radius of curvature at each point;c) calculates a tractor path, each point of which is determined by length, H, and the radius of curvature at a corresponding point on the hitch path;c) guides the tractor along the tractor path using the tractor position and speed information; and,d) maintains the implement on the implement path using the implement position and speed information. 21. The system of claim 20 wherein the tractor position and speed sensors and the implement position and speed sensors are based on GNSS receivers. 22. The system of claim 20 wherein the autopilot memory further stores a terrain map and the autopilot further adjusts the tractor path uphill by an amount that is a function of L and the uphill slope of the terrain. 23. The system of claim 20 wherein L=0. 24. A method for guiding an agricultural implement along a desired path comprising: providing a desired path for an agricultural implement;using known data to determine a required tractor path that, when followed by a tractor pulling the implement, will result in the implement following the desired path in the absence of disturbances; and,guiding the tractor along the required tractor path;wherein the known data comprise information pertaining to curves in the desired path. 25. A method for guiding an agricultural implement along a desired path comprising: providing a desired path for an agricultural implement;using known data to determine a required tractor path that, when followed by a tractor pulling the implement, will result in the implement following the desired path in the absence of disturbances; and,guiding the tractor along the required tractor path;wherein the known data comprise information pertaining to terrain slope on the desired path. 26. The method of claim 25, the known data further comprising information pertaining to soil conditions on the desired path. 27. A method for guiding an agricultural implement along a desired path comprising: providing a desired path for an agricultural implement;using known data to determine a required tractor path that, when followed by a tractor pulling the implement, will result in the implement following the desired path in the absence of disturbances;guiding the tractor along the required tractor path;using feedback control to maintain the implement on the desired path in the presence of disturbances; and,using live measurements to adjust a feedback set-point in the feedback control;wherein the live measurements comprise information pertaining to charges in terrain slopes on the desired path. 28. The method of claim 27, the information obtained from a tractor attitude sensor. 29. A method for guiding an agricultural implement along a desired path comprising: providing a desired path for an agricultural implement;using known data to determine a required tractor path that, when followed by a tractor pulling the implement, will result in the implement following the desired path in the absence of disturbances;guiding the tractor along the required tractor path;using feedback control to maintain the implement on the desired path in the presence of disturbances; and,recording actual implement and tractor paths for future use. 30. The method of claim 29 using recorded implement or tractor paths to infer soil conditions encountered on the desired path.