Method and apparatus for a limp home mode

• US 6,253,136 B1
• Filed: 03/31/1999
• Issued: 06/26/2001
• Est. Priority Date: 03/31/1999
• Status: Expired due to Term

• Current Assignee: Caterpillar Incorporated
• Original Assignee: Caterpillar Incorporated
• Inventors: Funke, Brian G., Kruase, Steven R., Stratton, Kenneth L., Skiba, Richard J., Genseal, Steven R.
• Primary Examiner(s): Cuchlinski, Jr., William A.
• Assistant Examiner(s): MANCHO, RONNIE M
• Application Number:
  US09/282,382
• Time in Patent Office: 818 Days
• Field of Search: 701/50, 701/62, 701/63, 172/4, 172/3, 172/7, 172/9, 172/86-89, 172/820, 144/4.1, 144/34.1, 414/729
• US Class Current: 701/50
• CPC Class Codes: A01B 63/00 Lifting or adjusting devices or arrangements for agricultural machines or implements lifting mechanisms for the cutter-bar of a mower A01D34/24; adjusting devices for the cutter-bar of a mower A01D34/28; constructional features of lifting devices per se B66F
• CPC Class Codes: E02F 3/7609 Scraper blade mounted forwardly of the tractor on a pair of pivoting arms which are linked to the sides of the tractor, e.g. bulldozers
• CPC Class Codes: E02F 3/963 Arrangements on backhoes for alternate use of different tools backhoes per se E02F3/30; quick-acting devices to connect tools to arms E02F3/3609, for arms to tractors or the like E02F3/627
• CPC Class Codes: E02F 9/22 Hydraulic or pneumatic drives for dipper or bucket arm position control E02F3/43, for blade position control for graders E02F3/844; for turntables E02F9/121; for fork-lift trucks B66F9/22
• CPC Class Codes: E02F 9/268 with failure correction follow-up actions

Abstract

The present invention provides a method and apparatus for controlling a work implement in order to enable an earth moving machine to move to a service area after a failure within an implement control system occurs. The method includes the steps of detecting the failure of the implement control system, enabling a limp home mode in response to the failure, and controlling the implement into a limp home position through operator interaction using a display and either an associated keypad or a touch screen.

Claims

1. A method for controlling a work implement after a failure within an implement control system has occurred, comprising the steps of:

detecting the failure of the implement control system;

enabling a limp home mode in response to the failure;

providing a potential implement command to an operator using a display;

receiving an operator implement command through interaction with an operator input device; and

controlling the implement into a limp home position in response to said operator implement command.

2. A method, as set forth in claim 1, wherein said failure includes an implement joystick failure.

3. A method, as set forth in claim 2, wherein said failure includes a solenoid failure.

4. A method, as set forth in claim 3, including the steps of:

determining the detected failure will prevent implement movement; and

disabling said limp home mode in response to said determination.

5. A method, as set forth in claim 4, including the step of determining a series of implement commands which will result in placing the implement in a limp home position.

6. A method, as set forth in claim 5, wherein each of said series of implement commands incrementally reposition the implement.

7. A method, as set forth in claim 6, wherein each said implement command is less than two seconds in duration.

8. A method, as set forth in claim 7, wherein each implement command energizes at least one valve to a full open position for a short predetermined time duration.

9. A method, as set forth in claim 8, wherein said work implement is a blade, and said limp home position is a raised position, and wherein moving a blade to a raised position includes a plurality of incremental raise blade commands being delivered to at least one valve associated with said blade, each said blade command causing the blade to raise an incremental amount.

10. A method, as set forth in claim 9, wherein said operator implement command is entered using said keypad.

19. A method, as set forth in claim 1, wherein the step of controlling the implement into a limp home position further includes the steps of:

controlling the implement in response to said operator input command;

providing a second potential implement command to said operator;

receiving a second operator implement command; and

controlling the implement in response to said second operator implement command.

20. A method, as set forth in claim 19, wherein the step of providing a potential implement command includes the steps of:

determining a sequence of implement commands configured to control the implement into a limp home position; and

providing said potential implement command in response to said determined command sequence.

21. A method, as set forth in claim 19, wherein the step of providing a potential implement command includes the steps of:

determining at least one implement command configured to control the implement into a limp home position; and

providing said potential implement command in response to said determined at least one implement command.

22. A method, as set forth in claim 1, wherein the step of controlling the implement into a limp home position further includes the steps of:

determining a sequence of implement commands configured to control the implement into a limp home position; and

automatically controlling the implement into a limp home position in response to said operator input command and said determined sequence of commands.

23. A method, as set forth in claim 1, wherein said operator input device includes one of a key pad or a touch screen.

11. An apparatus adapted to control a work implement after a failure within an implement control system has occurred, the apparatus including at least one cylinder connected to the work implement, comprising:

a means for detecting a failure within an implement control system and responsively generating a failure signal;

an operator interface adapted to receive an operator input and responsively generate an operator input signal, and receive and display an recommended implement command;

a controller adapted to receive said operator input signal, determine a failure has occurred within said implement control system, enable a limp home mode in response to said failure, generate said recommended implement command in response to said failure, and control said implement in response to said operator input signal.

12. An apparatus, as set forth in claim 11, wherein said operator interface includes:

an implement control joys tick; and

at least one of a keypad and a display, or a touch screen display adapted to receive an operator input.

13. An apparatus, as set forth in claim 12, wherein said failure includes at least one of an implement joystick failure or a solenoid failure.

14. An apparatus, as set forth in claim 13, wherein said controller is further adapted to determine a sequence of implement commands configured to control the implement into a limp home position an implement command to an operator in response to said failure, recommend said implement command in response to said determined command sequence, receive said operator input command in response to said recommendation, and control the implement in response to said operator input command.

15. An apparatus, as set forth in claim 14, wherein said controller is further adapted to determine said failure will prevent implement movement, and disable said limp home mode in response to said determination.

16. An apparatus, as set forth in claim 15, wherein said controller is further adapted to determine a series of implement commands which will result in placing the implement in a limp home position.

17. An apparatus, as set forth in claim 16, wherein each of said series of implement commands incrementally reposition the implement.

18. An apparatus, as set forth in claim 17, wherein each said incremental implement command is generated for less than two seconds.