Implement guidance

Patent metadata

Field	Value
Publication number	US-10019010-B2
Application number	US-201615247680-A
Country	US
Kind code	B2
Filing date	Aug 25, 2016
Priority date	Jun 2, 2014
Publication date	Jul 10, 2018
Grant date	Jul 10, 2018

Abstract

Efficient towed implement guidance to a desired path is achieved by guiding a towing vehicle toward a path on the opposite side of a desired path, then guiding the vehicle back to the desired path. Efficient forward implement guidance to a desired path is achieved by guiding a pushing vehicle along a tractrix. A vehicle leaves a straight line along a tractrix to keep a rear implement on the line as long as possible.

First claim

What is claimed is:

1. A method for guiding a forward implement on a desired path comprising:
a path-planning autopilot first guiding a vehicle, to which the forward implement is attached, toward the desired path at an approach angle to the desired path less than or equal to a pre-defined maximum angle; and,
once the implement reaches the desired path, the autopilot then guiding a vehicle control point along a tractrix parameterized by a distance, F, wherein the distance F is the distance of the implement ahead of the vehicle control point.

2. The method of claim 1 further comprising:
the path-planning autopilot planning a vehicle path from an initial vehicle configuration to a point where the implement is on the desired path and the vehicle heading does not exceed a maximum angle away from the desired path.

3. The method of claim 2 where curvature of the planned vehicle path at the point is determined by the maximum angle and the tractrix.

4. The method of claim 1 wherein the vehicle has a wheelbase, B, and F is greater than B.

5. The method of claim 1 wherein the vehicle has a wheelbase, B, and F equals B.

6. The method of claim 1 wherein the vehicle has a wheelbase, B and F is less than B.

7. The method of claim 1 further comprising: once the vehicle is established on the desired path, the autopilot then resuming normal vehicle guidance along the desired path.

8. The method of claim 1 , the autopilot offering direct control over maximum permitted vehicle steering angle.

9. The method of claim 1 , the autopilot offering direct control over maximum permitted vehicle steering angle rate.

10. A vehicle autopilot comprising:
a microprocessor and memory;
a GNSS receiver that provides vehicle position, velocity and time estimates to the microprocessor;
a feedback controller and a feed-forward controller that generate vehicle curvature commands to guide the vehicle; and,
a vehicle steering actuator; wherein,
the autopilot guides a vehicle control point along a tractrix parameterized by a characteristic of an implement attached to the vehicle, the implement being a forward implement and the tractrix parameterized by a distance, F, wherein the distance F is the distance of the implement ahead of the vehicle control point.

11. The autopilot of claim 10 wherein the autopilot is a path planning autopilot.

12. The autopilot of claim 10 wherein the vehicle has a wheelbase, B, and F is greater than B.

13. The autopilot of claim 10 wherein the vehicle has a wheelbase, B, and F equals B.

14. The autopilot of claim 10 wherein the vehicle has a wheelbase, B, and F is less than B.

15. The autopilot of claim 10 , the autopilot offering direct control over maximum permitted vehicle steering angle.

16. The autopilot of claim 10 , the autopilot offering direct control over maximum permitted vehicle steering angle rate.

17. The autopilot of claim 10 , the GNSS receiver using differential corrections provided by the Wide Area Augmentation System.

18. The autopilot of claim 10 , the GNSS receiver using real-time kinematic positioning techniques.

Assignees

• Trimble Inc

Inventors

• Peake John W
• Pleines Stephan

Classifications

• G05D1/0217

  in accordance with energy consumption, time reduction or distance reduction criteria · CPC title

• A01B69/008

  automatic · CPC title

• G05D1/0212 Primary

  with means for defining a desired trajectory (involving a plurality of land vehicles G05D1/0287) · CPC title

• A01B69/004

  automatic · CPC title

• G05D1/0219 Primary

  ensuring the processing of the whole working surface · CPC title