SYSTEM WITH SMART STEERING FORCE FEEDBACK

• US 20140214278A1
• Filed: 01/25/2013
• Published: 07/31/2014
• Est. Priority Date: 01/25/2013
• Status: Active Grant

• Current Assignee: Caterpillar Incorporated
• Original Assignee: Caterpillar Incorporated
• Inventors: KUIPERS, BEAU DANIEL, MATE, EDWARD WILLIAM, MORK, DAVID ARTHUR
• Granted Patent: US 9,050,999 B2
• Time in Patent Office: Days
• US Class Current: 701/42
• CPC Class Codes: B62D 6/008 Control of feed-back to the steering input member, e.g. simulating road feel in steer-by-wire applications
• CPC Class Codes: G05B 13/00 Adaptive control systems, i.e. systems automatically adjusting themselves to have a performance which is optimum according to some preassigned criterion G05B19/00 takes precedence
• CPC Class Codes: G05D 1/00 Control of position, course, altitude or attitude of land, water, air or space vehicles, e.g. using automatic pilots drive control systems specially adapted for autonomous road vehicles B60W60/00
• CPC Class Codes: G05D 3/12 using feedback

Abstract

A steering system and method for providing a force feedback to an operator input device are disclosed. The method may determine an actual position of the operator input device. The method may determine a desired steering mechanism position of a steering mechanism based on the actual position of the operator input device. The method may determine an actual steering mechanism position of the steering mechanism. The method may compare the actual steering mechanism position to the desired steering mechanism position and to a previous desired steering mechanism position. The method may generate a command that selectively activates force feedback to the operator input device based on the comparison.

Claims

1. A method for providing a force feedback to an operator input device, comprising:

determining an actual input operation parameter of the operator input device;

determining a desired steering operation parameter of a steering mechanism based on the actual input operation parameter of the operator input device;

determining an actual steering operation parameter of the steering mechanism;

comparing the actual steering operation parameter to the desired steering operation parameter and to a previous desired steering operation parameter; and

generating a command that selectively activates the force feedback to the operator input device based on the comparison.

2. The method of claim 1, wherein generating the command that selectively activates the force feedback to the operator input device further includes:

generating a command to activate the force feedback when the desired steering operation parameter is different from the previous desired steering operation parameter and when the actual steering operation parameter is different from the desired steering operation parameter.

3. The method of claim 2, wherein the force feedback that is activated is proportional to an error difference between the desired steering operation parameter and the actual steering operation parameter.

4. The method of claim 1, wherein generating the command to selectively activate the force feedback to the operator input device further includes:

generating a command to not activate the force feedback when the desired steering operation parameter and the previous desired steering operation parameter are the same, or when the desired steering operation parameter and the previous desired steering operation parameter are different and the actual steering operation parameter and the desired steering operation parameter are the same.

5. The method of claim 1, wherein:

the actual input operation parameter of the operator input device includes an actual position of the operator input device;

the desired steering operation parameter of the steering mechanism includes a desired steering mechanism position;

the actual steering operation parameter of the steering mechanism includes an actual steering mechanism position; and

the previous desired steering operation parameter includes a previous desired steering mechanism position.

6. The method of claim 5, wherein:

the actual position of the operator input device is determined by using one or more position sensors associated with the operator input device; and

the actual steering mechanism position is determined by using at least one of a cylinder position sensor associated with a hydraulic cylinder configured to actuate the steering mechanism, wherein the cylinder position sensor is configured to sense a cylinder position of the hydraulic cylinder, or an articulation angle sensor associated with the steering mechanism, wherein the articulation angle sensor is configured to sense an articulation angle of the steering mechanism.

7. The method of claim 1, wherein determining the desired steering operation parameter based on the actual input operation parameter includes using a map that correlates the desired steering operation parameter with the actual input operation parameter and a speed of a machine being steered by the operator input device.

8. A force feedback control system for providing a force feedback to an operator input device, comprising:

one or more memories storing instructions; and

one or more processors configured to execute the instructions to perform operations, including;

determining an actual input operation parameter of the operator input device;

determining a desired steering operation parameter of a steering mechanism based on the actual input operation parameter of the operator input device;

determining an actual steering operation parameter of the steering mechanism;

comparing the actual steering operation parameter to the desired steering operation parameter and to a previous desired steering operation parameter; and

generating a command that selectively activates the force feedback to the operator input device based on the comparison.

9. The control system of claim 8, wherein the one or more processors are further configured to execute the instructions to perform:

generating a command to activate the force feedback to the operator input device when the desired steering operation parameter is different from the previous desired steering operation parameter and when the actual steering operation parameter is different from the desired steering operation parameter.

10. The control system of claim 9, wherein the force feedback that is activated is proportional to an error difference between the desired steering operation parameter and the actual steering operation parameter.

11. The control system of claim 8, wherein the one or more processors are further configured to execute the instructions to perform:

generating a command to not activate the force feedback to the operator input device when the desired steering operation parameter and the previous desired steering operation parameter are the same, or when the desired steering operation parameter and the previous desired steering operation parameter are different and the actual steering operation parameter and the desired steering operation parameter are the same.

12. The control system of claim 8, wherein the one or more processors are further configured to execute the instructions to perform:

determining the desired steering operation parameter based on the actual input operation parameter of the operator input device by using a map that correlates the desired steering operation parameter with the actual input operation parameter and a speed of a machine being steered by the operator input device.

13. A steering system, comprising:

an operator input device configured to control one or more fraction devices of a machine;

a steering mechanism associated with the operator input device, configured to move the one or more traction devices according to the operator input device;

one or more steering input sensors associated with the operator input device; and

a controller configured to provide a force feedback to the operator input device, by;

determining an actual input operation parameter of the operator input device by using the one or more steering input sensors associated with the operator input device;

determining a desired steering operation parameter of the steering mechanism based on the actual input operation parameter;

determining an actual steering operation parameter of the steering mechanism;

comparing the actual steering operation parameter to the desired steering operation parameter and to a previous desired steering operation parameter; and

generating a command that selectively activates the force feedback to the operator input device based on the comparison.

14. The steering system of claim 13, wherein the controller is further configured to:

generate a command to activate the force feedback to the operator input device when the desired steering operation parameter is different from the previous desired steering operation parameter and when the actual steering operation parameter is different from the desired steering operation parameter.

15. The steering system of claim 14, wherein the force feedback that is activated is proportional to an error difference between the desired steering operation parameter and the actual steering operation parameter.

16. The steering system of claim 13, wherein the controller is further configured to:

generate a command to not activate the force feedback to the operator input device when the desired steering operation parameter and the previous desired steering operation parameter are the same, or when the desired steering operation parameter and the previous desired steering operation parameter are different and the actual steering operation parameter and the desired steering operation parameter are the same.

17. The steering system of claim 13, wherein the controller is further configured to:

determine the desired steering operation parameter based on the actual input operation parameter of the operator input device by using a map that correlates the desired steering operation parameter with the actual input operation parameter and a speed of the machine.

18. The steering system of claim 13, wherein:

the actual input operation parameter of the operator input device includes an actual position of the operator input device;

the desired steering operation parameter of the steering mechanism includes a desired steering mechanism position;

the actual steering operation parameter of the steering mechanism includes an actual steering mechanism position; and

the previous desired steering operation parameter includes a previous desired steering mechanism position.

19. The steering system of claim 18, further including:

at least one of a cylinder position sensor associated with a hydraulic cylinder configured to actuate the steering mechanism, wherein the cylinder position sensor is configured to sense a cylinder position of the hydraulic cylinder, or an articulation angle sensor associated with the steering mechanism, wherein the articulation angle sensor is configured to sense an articulation angle of the steering mechanism,

wherein the controller is further configured to determine the actual steering mechanism position of the steering mechanism based on the at least one of the cylinder position sensor associated or the articulation angle sensor.

20. A machine comprising the steering system of claim 13, further including:

a power source; and

the one or more traction devices driven by the power source to move the machine, wherein the steering system provides steering to the one or more traction devices.