Adaptive work cycle control system

• US 8,024,095 B2
• Filed: 03/07/2008
• Issued: 09/20/2011
• Est. Priority Date: 03/07/2008
• Status: Active Grant

• Current Assignee: Caterpillar Incorporated
• Original Assignee: Caterpillar Incorporated
• Inventors: Tozawa, Shoji, Kowta, Srinivas, Venkateswaran, Parmesh, King, Kevin D., Price, Robert J., Janardhan, Vijayakumar, Mintah, Brian
• Primary Examiner(s): Hellner; Mark
• Assistant Examiner(s): MAWARI, REDHWAN K
• Application Number:
  US12/073,671
• Publication Number:
  US 20090228177A1
• Time in Patent Office: 1,292 Days
• Field of Search: 701/35, 701/36, 701/50, 172/1, 172/2, 373/48
• US Class Current: 701/50
• CPC Class Codes: E02F 3/435 for dipper-arms, backhoes or the like
• CPC Class Codes: E02F 9/24 Safety devices , e.g. for preventing overload E02F9/226 takes precedence
• CPC Class Codes: E02F 9/26 Indicating devices E02F5/145 takes precedence
• CPC Class Codes: E02F 9/264 Sensors and their calibration for indicating the position of the work tool

Abstract

A control system for an excavation machine is disclosed. The control system may have a work tool movable to perform an excavation work cycle, at least one sensor configured to monitor a speed of the work tool and generate a signal indicative of the monitored speed, and a controller in communication with the at least one sensor. The controller may be configured to record the monitored speed of the work tool during each excavation work cycle, and compare the signal currently being generated to a maximum speed recorded for a previous excavation work cycle. The controller may be further configured to partition a current excavation work cycle into a plurality of segments based on the comparison.

Claims

1. A control system, comprising:

a work tool movable to perform an excavation work cycle including multiple work cycle segments;

a plurality of sensors operatively coupled to the work tool, the plurality of sensors including;

a first sensor configured to monitor a first speed of the work tool;

a second sensor configured to monitor a second speed of the work tool, the second speed being different from the first speed;

a third sensor configured to monitor a force of the work tool; and

a controller in communication with the at least first sensor, second sensor, and third sensor and configured to;

record the monitored first speed, second speed, and force of the work tool during each excavation work cycle;

compare a current first speed to a maximum first speed recorded for a previous excavation work cycle;

compare a current second speed to a threshold speed value;

compare a current force to a threshold force value; and

identify a current work cycle segment based at least in part on at least two of (i) the comparison of the first speed, (ii) the comparison of the second speed, and (iii) the comparison of the force.

2. The control system of claim 1, wherein the multiple work cycle segments include a dig segment, a first swing segment, a dump segment, and a second swing segment.

3. The control system of claim 2, wherein:

the first speed is a swing speed of the work tool;

the second speed is a pivot speed of the work tool; and

the controller is configured to identify the current work cycle segment as the first swing segment when (i) a current swing speed in a first direction exceeds a predetermined amount of a maximum swing speed in the first direction achieved during the previous excavation work cycle, (ii) a current pivot speed in a second direction exceeds a threshold speed value, and (iii) a current force of the work tool is below a threshold force.

4. The control system of claim 3, wherein:

the predetermined amount is about 20% of the maximum swing speed achieved during the previous excavation work cycle; and

the threshold speed value is about 5°

/sec.

5. The control system of claim 3, wherein the controller is configured to identify the current work cycle segment as the dump segment when (i) the current swing speed in the first direction is below a predetermined amount of the maximum swing speed in the first direction achieved during the previous excavation work cycle, (ii) the current pivot speed in the second direction is below a threshold speed value, and (iii) the current force of the work tool exceeds a threshold force.

6. The control system of claim 3, wherein the controller is configured to identify the current work cycle segment as the second swing segment when (i) the current swing speed in a third direction opposite the first direction exceeds a predetermined amount of a maximum swing speed in the third direction achieved during the previous excavation work cycle, (ii) a direction of the current pivot speed is in a fourth direction opposite the second direction, and (iii) the current force of the work tool is below a threshold force.

7. The control system of claim 3, wherein the controller is configured to identify the current work cycle segment as the dig segment when (i) the current swing speed of the work tool in a third direction opposite the first direction is below a predetermined amount of a maximum swing speed in the third direction achieved during the previous excavation work cycle, and (ii) the current force of the work tool exceeds a threshold force.

8. The control system of claim 1, further including:

a linkage member operatively connected to the work tool;

a first actuator configured to swing the work tool in a first direction;

a second actuator configured to pivot the work tool in a second direction;

a third actuator configured to pivot the work tool relative to the linkage member; and

at least one operator input device configured to generate a signal indicative of an operator desired movement of at least one of the first, second, and third actuators.

9. The control system of claim 1, further including a timer, wherein the controller is in communication with the timer and configured to relate a complete excavation work cycle and each of the plurality of segments to an elapsed period of time.

10. A method of identifying a current work cycle segment of a work tool operating in an excavation work cycle including multiple work cycle segments, the method comprising:

monitoring a first speed of a work tool;

monitoring a second speed of the work tool, the second speed being different from the first speed;

monitoring a force of the work tool;

recording the monitored first speed, second speed, and force during each excavation work cycle;

comparing a current first speed of the work tool to a maximum first speed recorded for a previous excavation work cycle;

comparing a current second speed of the work tool to a threshold speed value;

comparing a current force of the work tool to a threshold force value; and

identifying a current work cycle segment of the work tool based at least in part on at least two of (i) the comparison of the current first speed, (ii) the comparison of the current second speed, and (iii) the comparison of the force.

11. The method of claim 10, wherein the multiple work cycle segments include a dig segment, a first swing segment, a dump segment, and a second swing segment.

18. The method of claim 11, wherein identifying a current work cycle segment includes identifying the current work cycle segment as the first swing segment when (i) the current swing speed in a first direction exceeds a predetermined amount of a maximum swing speed in the first direction achieved during the previous excavation work cycle, (ii) the current pivot speed in a second direction exceeds a threshold speed value, and (iii) the current force is below a threshold force.

19. The method of claim 18, wherein the predetermined amount is about 20% and the threshold speed value is about 5°

/sec.

20. The method of claim 11, wherein identifying a current work cycle segment includes identifying the current work cycle segment as the dump segment when (i) the current swing speed in a first direction is below a predetermined amount of the maximum swing speed in the first direction achieved during the previous excavation work cycle, (ii) the current pivot speed in the second direction is below a threshold speed value, and (iii) the current force of the work tool exceeds a threshold force.

12. A machine, comprising:

a frame;

a boom member connected to swing and pivot relative to the frame;

a work tool operatively connected to the boom member and adapted to operate in an excavation work cycle including multiple work cycle segments, the multiple work cycle segments including at least a dig segment, a first swing segment, a dump segment and a second swing segment;

a first sensor configured to monitor a swing speed of the boom member and generate a first signal indicative of the monitored swing speed;

a second sensor configured to monitor a pivot speed of the boom member and generate a second signal indicative of the monitored pivot speed;

a third sensor configured to monitor a force of the work tool and generate a third signal indicative of the monitored pivot speed; and

a controller in communication with the first, second, and third sensors and being configured to;

record the monitored swing speed, pivot speed, and force of the work tool during each excavation work cycle;

compare a current swing speed to a maximum swing speed recorded for a previous excavation work cycle;

compare a current pivot speed to a threshold speed value;

compare a current force to a threshold force value ; and

identify a current work cycle segment based at least in part on at least two of (i) the comparison of the current swing speed, (ii) the comparison of the current pivot speed, and (iii) the comparison of the current force, the current work cycle segment being one of the dig segment, the first swing segment, the dump segment and the second swing segment.

13. The machine of claim 12, wherein the controller is configured to identify the current work cycle segment as the first swing segment when the current swing speed in a first direction exceeds a predetermined amount of a maximum swing speed in the first direction achieved during the previous excavation work cycle, the current pivot speed in a second direction exceeds a threshold speed value, and the current force is below a threshold force.

14. The machine of claim 13, wherein:

the predetermined amount is about 20% of the maximum swing speed achieved during the previous excavation work cycle; and

the threshold speed value is about 5°

/sec.

15. The machine of claim 13, wherein the controller is configured to identify the current work cycle segment as the dump segment when (i) the current swing speed in the first direction is below a predetermined amount of the maximum swing speed in the first direction achieved during the previous excavation work cycle, (ii) the current pivot speed in the second direction is below a threshold speed value, and (iii) the current force of the work tool exceeds a threshold force.

16. The machine of claim 15, wherein the controller is configured to identify the current work cycle segment as the second swing segment when (i) the current swing speed in a third direction opposite the first direction exceeds a predetermined amount of a maximum swing speed in the third direction achieved during the previous excavation work cycle, (ii) a direction of the current pivot speed is in a fourth direction opposite the second direction, and (iii) the current force of the work tool is below a threshold force.

17. The machine of claim 15, wherein the controller is configured to identify the current work cycle segment as the dig segment when (i) the current swing speed in a third direction opposite the first direction is below a predetermined amount of a maximum swing speed in the third direction achieved during the previous excavation work cycle, and (ii) the current force of the work tool exceeds a threshold force.