System and method for controlling stability of milling machines

• US 9,956,842 B2
• Filed: 10/13/2015
• Issued: 05/01/2018
• Est. Priority Date: 10/13/2015
• Status: Active Grant

• Current Assignee: Caterpillar Power Systems Incorporated (Caterpillar Incorporated)
• Original Assignee: Caterpillar Power Systems Incorporated (Caterpillar Incorporated)
• Inventors: Muir, Jason W., O'Donnell, Timothy M., Sansone, Dario
• Primary Examiner(s): Kreck, John J
• Application Number:
  US14/881,621
• Publication Number:
  US 20170100981A1
• Time in Patent Office: 931 Days
• CPC Class Codes: B60G 17/0165 to an external condition, e.g. rough road surface, side wind
• CPC Class Codes: B60G 17/01908 Acceleration or inclination sensors characterised by the use of gyroscopes B60G21/08
• CPC Class Codes: B60G 2400/0511 Roll angle
• CPC Class Codes: B60G 2400/0512 Pitch angle
• CPC Class Codes: B60G 2400/0521 Roll rate
• CPC Class Codes: B60G 2400/82 Ground surface
• CPC Class Codes: E01C 23/088 Rotary tools, e.g. milling drums for forming recesses to receive marking materials E01C23/0946
• CPC Class Codes: E01C 23/127 rotary, e.g. rotary hammers

Abstract

A system for controlling a stability of a milling machine is disclosed. The system includes a frame having a first slope and a leg coupled to the frame. The leg extends and retracts along a length thereof with respect to the frame. The system includes a controller to determine the first slope and to actuate the leg if the first slope is greater than a first predetermined slope.

Claims

1. A system for controlling a stability of a milling machine, the system comprising:

a frame;

a plurality of legs extending between the frame and a ground surface, each leg of the plurality of legs being configured to extend and retract along a length thereof with respect to the frame; and

a controller configured to;

determine a first slope of the frame, the first slope being indicative of an inclination of the milling machine with respect to the ground surface; and

actuate one or more legs of the plurality of legs to decrease the inclination of the milling machine based on a comparison of the first slope to a first predetermined slope, wherein the first predetermined slope is indicative of a stability limit of the milling machine.

2. The system of claim 1, wherein the controller is configured to actuate the one or more legs if the first slope is greater than or equal to the first predetermined slope.

3. The system of claim 1, wherein the first predetermined slope is a function of at least one of a length, a wheel base, a height, and a weight of the milling machine.

4. The system of claim 1, wherein the first slope is further indicative of the inclination of the milling machine with reference to a longitudinal axis of the milling machine, and wherein the controller is further configured to:

determine a second slope, wherein the second slope is indicative of the inclination of the milling machine with reference to a transverse axis of the milling machine; and

actuate one or more legs of the plurality of legs if the second slope is greater than or equal to a second predetermined slope, wherein the second predetermined slope is indicative of a stability limit of the milling machine with reference to the transverse axis.

5. The system of claim 2, wherein the first predetermined slope is fifteen degrees.

6. The system of claim 1, wherein the controller is configured to actuate one or more legs of the plurality of legs until the first slope is reduced to a third predetermined slope, and wherein the third predetermined slope is less than or equal to the first predetermined slope.

7. The system of claim 1, wherein the controller is further configured to:

determine a height of each leg of the plurality of the legs; and

actuate at least one leg of the plurality of the legs based on the determined height and the first slope.

8. A milling machine comprising:

a frame;

a rotor coupled to the frame; and

a first length adjustable leg coupled to the frame;

a second length adjustable leg coupled to the frame;

a third length adjustable leg coupled to the frame;

a fourth length adjustable leg coupled to the frame; and

a controller configured to;

determine an inclination of the frame with respect to a ground surface; and

actuate an actuatable leg to decrease the inclination based on a comparison of the determined inclination to a predetermined stability limit of the milling machine, wherein the actuatable leg is at least one of the first length adjustable leg, the second length adjustable leg, the third length adjustable leg, and the fourth length adjustable leg.

9. The milling machine of claim 8, wherein the controller is configured to actuate the actuatable leg when the determined inclination is greater than or equal to the predetermined stability limit, and the controller is further configured to:

stop actuation of the actuatable leg when the determined inclination is less than or equal to the predetermined stability limit.

10. The milling machine of claim 9, wherein the controller is further configured to:

determine a first height of the first length adjustable leg;

determine a second height of the second length adjustable leg;

determine a third height of the third length adjustable leg; and

determine a fourth height of the fourth length adjustable leg.

11. The milling machine of claim 10, wherein the controller is further configured to:

determine the actuatable leg based on the first height, the second height, the third height, the fourth height, and the determined inclination.

12. The milling machine of claim 11, wherein the determined inclination is a first inclination of the frame along a longitudinal axis of the milling machine and the predetermined stability limit is the stability limit of the milling machine along the longitudinal axis, and the controller is further configured to:

determine a second inclination, wherein the second inclination is an inclination of the frame with respect to the ground surface along a transverse axis of the milling machine; and

actuate a second actuatable leg when the second inclination is greater than or equal to a second predetermined stability limit, wherein the second actuatable leg is at least one of the first length adjustable leg, the second length adjustable leg, the third length adjustable leg, and the fourth length adjustable leg, and wherein the second predetermined stability limit is the stability limit of the milling machine along the transverse axis.

13. The milling machine of claim 12, wherein the controller is further configured to:

determine the second actuatable leg based on the first height, the second height, the third height, the fourth height, and the second inclination.

14. The milling machine of claim 8, wherein the predetermined stability limit is a function of a size of the milling machine.

15. The milling machine of claim 8, wherein the predetermined stability limit is a function of at least one of a length, a wheel base, a height, and a weight of the milling machine.

16. The milling machine of claim 8, wherein the predetermined stability limit is fifteen degrees.

17. A method of controlling a stability of a milling machine comprising:

moving a ground engaging member of the milling machine over a ground surface, wherein the ground engaging member is coupled to a frame of the milling machine by a leg;

determining a first slope of the frame, wherein the first slope is indicative of an inclination of the milling machine with respect to the ground surface; and

actuating the leg to decrease the inclination of the milling machine based on a comparison of the first slope to a first predetermined slope, wherein the first predetermined slope is indicative of a stability limit of the milling machine and is a function of a size of the milling machine.

18. The method of claim 17, wherein the first slope is indicative of the inclination of the milling machine along a longitudinal axis of the milling machine and the first predetermined slope is indicative of a stability limit of the milling machine along the longitudinal axis, the method further comprising:

determining a second slope of the frame, wherein the second slope is indicative of the inclination of the milling machine along a transverse axis of the milling machine; and

actuating the leg if the second slope is greater than or equal to a second predetermined slope, wherein the second predetermined slope is indicative of a stability limit of the milling machine along the transverse axis.

19. The method of claim 17, wherein the first predetermined stability limit is a function of at least one of a length, a wheel base, a height, and a weight of the milling machine.

20. The method of claim 17, further including determining the first predetermined stability limit from a lookup table.