Automatic articulation machine states

• US 9,217,238 B2
• Filed: 03/17/2014
• Issued: 12/22/2015
• Est. Priority Date: 03/17/2014
• Status: Active Grant

• Current Assignee: Caterpillar Incorporated
• Original Assignee: Caterpillar Incorporated
• Inventors: Sharma, Amit, Budde, Steven C., Moul, Matt I., De Veer, Brad Van, Hughes, Eric C.
• Primary Examiner(s): HOLLOWAY, JASON R
• Application Number:
  US14/216,440
• Publication Number:
  US 20150259881A1
• Time in Patent Office: 645 Days
• Field of Search: 701/50
• US Class Current: 1/1
• CPC Class Codes: B60Y 2200/411 Bulldozers, Graders
• CPC Class Codes: B62D 11/183 Control systems therefor
• CPC Class Codes: B62D 12/00 Steering specially adapted for vehicles operating in tandem or having pivotally connected frames steering endless tracks or the like B62D11/00; steering specially adapted for trailers B62D13/00
• CPC Class Codes: B62D 6/002 computing target steering angles for front or rear wheels B62D7/159 takes precedence
• CPC Class Codes: E02F 3/7659 with the vertical centre-line of the scraper blade disposed laterally relative to the central axis of the chassis
• CPC Class Codes: E02F 9/0841 Articulated frame, i.e. having at least one pivot point between two travelling gear units tractor-trailer combinations B62D53/00
• CPC Class Codes: E02F 9/2033 Limiting the movement of frames or implements, e.g. to avoid collision between implements and the cabin sub-groups of E02F3/431 of E02F3/435 take precedence; for turntables E02F9/123
• CPC Class Codes: E02F 9/2087 Control of vehicle steering for steering with hydraulic or pneumatic drives E02F9/225
• CPC Class Codes: E02F 9/225 Control of steering, e.g. for hydraulic motors driving the vehicle tracks steering in general B62D

Abstract

A controller monitors groundspeed in an articulated machine and selectively disables an automatic articulation control function when the groundspeed is at or near zero. If there is an indication that an operator may not be aware that the automatic articulation control function is active by comparing when a on switch was activated compared to a machine power cycle or an operator not being present, the automatic articulation control function may be inactivated until the on switch is toggled. If the articulated machine is in neutral and the groundspeed is at or near zero, the automatic articulation control function may disabled. If the groundspeed is at or near zero but the transmission is not in neutral, the machine may simply be stalled to due working conditions and the automatic articulation control function may be maintained.

Claims

1. A method of managing articulation in an articulated machine using an electronic controller, the method comprising:

determining, at the electronic controller, that the articulated machine is operating at a groundspeed below a minimum threshold speed; and

responsive to determining that the articulated machine is operating below the minimum threshold speed, disabling, at the electronic controller, an automatic articulation control function when one of either a first state or a second state is true,

the first state being a transmission of the articulated machine being in neutral, and

the second state being a mode selector set continuously on from prior to a machine key cycle or a machine power cycle.

2. The method of claim 1, further comprising:

when the automatic articulation control function is disabled as a result of the groundspeed being below the minimum threshold speed and the second state being true;

determining that a mode selector has been cycled off and on;

determining that the groundspeed is above the minimum threshold speed; and

enabling the automatic articulation control function to change an articulation angle of the articulated machine.

3. The method of claim 1, further comprising:

responsive to determining that the articulated machine is operating below the minimum threshold speed, maintaining operation of the automatic articulation control function when neither the first state nor the second state are true.

4. The method of claim 3, wherein the minimum threshold speed is about 0.9 meters per second.

5. The method of claim 1, further comprising controlling articulation of the articulated machine based on a steering angle of front wheels of the articulated machine.

6. The method of claim 1, further comprising:

when the automatic articulation control function is disabled as a result of the groundspeed being below the minimum threshold speed and one of the first or second state being true,

providing a notification at an operator station that the automatic articulation control function is disabled.

14. The method of claim 1, wherein the second state further includes an ‘

operator not present’

state.

7. A system for managing articulation in an articulated machine, the system comprising:

a controller that implements an automatic articulation control function in the articulated machine, the controller comprising;

a processor;

at least one sensor input that receives a groundspeed of the articulated machine; and

a memory storing data and computer-executable instructions that when executed by the processor cause the controller to;

determine that a mode selector is in an on state;

compare the groundspeed of the articulated machine to a minimum speed;

determine when the groundspeed is below the minimum speed;

when the groundspeed is below the minimum speed, determine when a condition exists that precludes operation of the automatic articulation control function, wherein the condition comprises at least one of the transmission being in neutral, the mode selector being continuously on since completion of a machine key cycle, or the mode selector being continuously on since completion of a power cycle of the articulated machine; and

prevent the automatic articulation control function from changing an articulation angle of the articulated machine when the groundspeed is below the minimum speed and the condition exists.

8. The controller of claim 7, wherein the memory stores further computer-executable instructions that when executed cause the processor to:

determine when the groundspeed is below the minimum speed and when the condition does not exist; and

when the groundspeed is below the minimum speed and when the condition does not exist, enable the automatic articulation control function to change the articulation angle of the articulated machine responsive to changes in a steering angle of front wheels of the articulation machine.

9. The controller of claim 7, wherein the condition further comprises the mode selector being continuously on since detecting an ‘

operator not present’

state.

10. The controller of claim 7, wherein the memory stores further computer-executable instructions that when executed cause the processor to:

determine when the groundspeed is above the minimum speed and enable the automatic articulation control function to change the articulation angle of the articulated machine responsive to changes in a steering angle of the front wheels when the groundspeed is above the minimum speed.

11. The controller of claim 7, further comprising an output that drives an indicator at an operator station, the indicator configured to provide a notification that the automatic articulation control function is disabled when the indicator is activated by the output.

12. A method of operating a controller that manages articulation angle in an articulated machine, the method comprising:

identifying that a mode selector is in an on position;

when a groundspeed of the articulated machine is below a threshold speed, identifying that a predetermined operating condition is true, wherein the predetermined operating condition comprises at least one of the transmission being in neutral, the mode selector being continuously on since completion of a machine key cycle, or the mode selector being continuously on since completion of a machine power cycle of the articulated machine; and

preventing the controller from changing the articulation angle of the articulated machine when the predetermined operating condition is identified as being true.

13. The method of claim 12, wherein the predetermined operating condition is the mode selector being continuously on since detecting an ‘

operator not present’

state.