Systems and Methods for Constrained Dozing
A computer-implemented method for determining an implement path for a machine implement at a worksite is provided. The computer-implemented method may include identifying a work surface and a pass target of the worksite, defining a loading profile based on one or more curves constrained to the work surface and the pass target, defining a carry profile based on the loading profile and the pass target, and designating the loading profile and the carry profile as the implement path.
The present disclosure relates generally to controlling machines, and more particularly, to systems and methods for determining blade paths for semi-autonomous and autonomous machines using constrained dozing techniques.
BACKGROUNDMachines such as, for example, track-type tractors, dozers, motor graders, wheel loaders, and the like, are used to perform a variety of tasks. For example, these machines may be used to move material and/or alter work surfaces at a worksite. In general, the machines may function in accordance with a work plan for a given worksite to perform operations, including digging, loosening, carrying, and any other manipulation of materials at the worksite. Furthermore, the work plan may often involve repetitive tasks that may be entirely or at least partially automated to minimize operator involvement. Accordingly, the machines may include not only manned machines, but also be autonomous or semi-autonomous vehicles that perform tasks in response to preprogrammed commands or commands delivered remotely or locally.
In such work environments, it is desirable to ensure that the machines perform work operations such that the materials are moved in an efficient and productive manner. In substantially automated work environments, the overall efficiency or productivity relies greatly on the predictability of each machine, or the ability of the machine to accurately execute the task according to the predetermined work plan. In dozing applications for instance, the predictability or the ability of the machine to accurately perform a cut along a given pass target can be affected by variations in the material being worked on, irregularities in the work surface, machine limitations, or any variety of other factors. Moreover, seemingly insignificant deviations in the initial few cuts may become compounded and pronounced after several iterations, which may require more time and effort to correct at the back end.
One way to improve predictability in dozing applications is to reduce the depth of each digging or cutting operation. More particularly, by lessening the load exerted on the machine, the machine behaves in a much more predictable and manageable manner. However, excessive reductions in the cutting depth may adversely affect overall efficiency and productivity. Thus, in at least dozing operations, it is important to define blade paths or blade positions that strike a careful balance between optimum productivity and predictability. Solutions exist, such as in U.S. Pat. No. 6,181,999 (“Yamamoto”), which provide machines that automatically vary blade position based on the load to provide smoother cuts and more predictable passes. Although Yamamoto may provide some benefit, it is still limited in that it functions in a manner that is localized and blind to the overall work plan.
Accordingly, there is a need for systems and methods which provide more intuitive means for planning implement or blade paths that not only improve machine predictability, but also improve overall efficiency and productivity. The present disclosure is directed at addressing one or more of the deficiencies and disadvantages set forth above. However, it should be appreciated that the solution of any particular problem is not a limitation on the scope of this disclosure or of the attached claims except to the extent express noted.
SUMMARY OF THE DISCLOSUREIn one aspect of the present disclosure, a computer-implemented method for determining an implement path for a machine implement at a worksite is provided. The computer-implemented method may include identifying a work surface and a pass target of the worksite, defining a loading profile based on one or more curves constrained to the work surface and the pass target, defining a carry profile based on the loading profile and the pass target, and designating the loading profile and the carry profile as the implement path.
In another aspect of the present disclosure, a control system for determining an implement path for a machine implement at a worksite is provided. The control system may include a memory configured to retrievably store one or more algorithms, and a controller in communication with the memory and, based on the one or more algorithms. The controller may be configured to at least identify a work surface and a pass target of the worksite, define a loading profile based on one or more curves constrained to the work surface and the pass target, and define a carry profile based on the loading profile and the pass target.
In yet another aspect of the present disclosure, a controller for determining an implement path for a machine implement at a worksite is provided. The controller may include a work surface identification module configured to identify a work surface of the worksite, a pass target identification module configured to identify a pass target of the worksite, a loading profile module configured to define a loading profile based on one or more curves constrained to the work surface and the pass target, and a carry profile module configured to define a carry profile based on the loading profile and the pass target.
Although the following sets forth a detailed description of numerous different embodiments, it should be understood that the legal scope of protection is defined by the words of the claims set forth at the end of this patent. The detailed description is to be construed as exemplary only and does not describe every possible embodiment since describing every possible embodiment would be impractical, if not impossible. Numerous alternative embodiments could be implemented, using either current technology or technology developed after the filing date of this patent, which would still fall within the scope of the claims defining the scope of protection.
It should also be understood that, unless a term is expressly defined herein, there is no intent to limit the meaning of that term, either expressly or by implication, beyond its plain or ordinary meaning, and such term should not be interpreted to be limited in scope based on any statement made in any section of this patent (other than the language of the claims). To the extent that any term recited in the claims at the end of this patent is referred to herein in a manner consistent with a single meaning, that is done for sake of clarity only so as to not confuse the reader, and it is not intended that such claim term be limited, by implication or otherwise, to that single meaning.
Referring now to
The overall operations of the machines 102 and the machine implements 104 within the worksite 100 may be managed by a control system 108 that is at least partially in communication with the machines 102. Moreover, each of the machines 102 may include any one or more of a variety of feedback devices 110 capable of signaling, tracking, monitoring, or otherwise communicating relevant machine information to the control system 108. For example, each machine 102 may include a locating device 112 configured to communicate with one or more satellites 114, which in turn, may communicate to the control system 108 various information pertaining to the position and/or orientation of the machines 102 relative to the worksite 100. Each machine 102 may additionally include one or more implement sensors 116 configured to track and communicate position and/or orientation information of the implements 104 to the control system 108. The implement sensors 116 may also communicate information pertaining to any sensed load on the implement 116, such as the relative weight of any material that is loaded into or carried by the blade of a dozing machine for instance.
The control system 108 may be implemented in any number of different arrangements. For example, the control system 108 may be at least partially implemented at a command center 118 situated locally or remotely relative to the worksite 100 with sufficient means for communicating with the machines 102, for example, via satellites 114, or the like. Additionally or alternatively, the control system 108 may be implemented using one or more computing devices 120 with means for communicating with one or more of the machines 102 or one or more command centers 118 that may be locally and/or remotely situated relative to the worksite 100. In still further alternatives, the control system 108 may be implemented on-board any one or more of the machines 102 that are also provided within the worksite 100. Other suitable modes of implementing the control system 108 are possible and will be understood by those of ordinary skill in the art.
Using any of the foregoing arrangements, the control system 108 may generally be configured to monitor the positions of the machines 102 and/or machine implements 104 relative to the worksite 100 and a predetermined target operation, and provide instructions for controlling the machines 102 and/or machine implements 104 in an efficient manner in executing the target operation. In certain embodiments, the machines 102 may be configured to excavate areas of a worksite 100 according to one or more predefined excavation plans. The excavation plans can include, among other things, determining the location, size, and shape of a plurality of cuts into an intended work surface 122 at the worksite 100 along one or more slots 124. In such embodiments, the control system 108 may be used to plan not only the overall excavation, but also to define an implement or blade path within the slots 124 or any other areas of the work surface 122. For a given work surface 122 and pass target, for instance, the control system 108 may define a blade path, composed of a loading profile and a carry profile, best suited to guide the machines 102 in an efficient, productive and predictable manner. Although described in connection with planning and profiling blade paths, the control system 108 may similarly be employed in conjunction with other types of tasks.
Turning to
As further shown in
The pass target identification module 134 of
As shown for example in
The carry profile module 138 of
Using this blade path 156 as a guide, or lower-bound, for the blade 104, for example, the controller 126 may engage the appropriate actuators 106 associated with the blade 104 of a dozing machine 102 to perform more predictable cuts. Furthermore, in dozing machines 102 with implement sensors 116 or other load-sensing capabilities, the controller 126 may enable features, which when used in conjunction with the blade path 156, can provide smoother slot surfaces. Specifically, the controller 126 may enable sensor-based implement controls to monitor the load of the blade 104 during a cutting operation, and automatically raise the blade 104 once the blade 104 is full or nearly full. When used in relation to a lower-bound that is defined by the blade path 156, for example, a dozing machine 102 may generally cut and load material into the blade 104 for approximately the first two-thirds of the loading profile 148 or until capacity is reached, and automatically raise the loaded blade 104 to a predetermined blade height to be carried along the remaining distance of the loading profile 148 and the carry profile 154. More particularly, the blade height may be predefined such that the blade 104 is at least partially in contact with the terrain as it is carried along the carry surface of the slot 124 in a way that smooths the surface and further promotes predictability for subsequent passes.
Other variations and modifications to the algorithms or methods will be apparent to those of ordinary skill in the art. Exemplary algorithms or methods by which the controller 126 may be operated to determine an implement path 156 for a machine implement 104 as well as to determine an appropriate slope for the loading profile 148 is discussed in more detail below.
INDUSTRIAL APPLICABILITYIn general, the present disclosure sets forth methods, devices and systems for planning implement or blade paths, or at least loading profiles thereof, where there are motivations to promote predictability and improve overall efficiency and productivity. Although applicable to any type of machine, the present disclosure may be particularly applicable to autonomously or semi-autonomously controlled dozing machines where the dozing machines are controlled along particular travel routes within a worksite to excavate materials. Moreover, the present disclosure produces more predictable results by reducing the load that is exerted on the machines and enabling the machines to execute cleaner passes, which further promotes the predictability of successive passes. Furthermore, by enabling smoother passes that are in better agreement with the work plan, the time and resources typically spent on correcting deviations from the work plan are substantially reduced, and overall efficiency is significantly improved.
Turning now to
Once information regarding the work surface 122 has been sufficiently identified, mapped or otherwise obtained, the controller 126 may further identify the pass target 146 according to block 158-2 of
According to block 158-3 of
Once the loading profile 148 has been determined, the controller 126 in block 158-5 of
Based on the blade path 156, the controller 126 may be able to instruct the machine 102 to dig, cut and carry material along the slot 124 in accordance with block 158-7 of
Turning now to
If the general slope of the given loading profile 148-1 is determined to be within acceptable limits, the controller 126 in block 160-4 of
From the foregoing, it will be appreciated that while only certain embodiments have been set forth for the purposes of illustration, alternatives and modifications will be apparent from the above description to those skilled in the art. These and other alternatives are considered equivalents and within the spirit and scope of this disclosure and the appended claims.
Claims
1. A computer-implemented method for determining an implement path for a machine implement at a worksite, comprising:
- identifying a work surface and a pass target of the worksite;
- defining a loading profile based on one or more curves constrained to the work surface and the pass target;
- defining a carry profile based on the loading profile and the pass target; and
- designating the loading profile and the carry profile as the implement path.
2. The computer-implemented method of claim 1, wherein one or more of the curves of the loading profile are based on a half-Gaussian curve.
3. The computer-implemented method of claim 1, wherein the loading profile is constrained to be tangent to the adjacent work surface at a start point thereof, and tangent to the adjacent pass target at an end point thereof.
4. The computer-implemented method of claim 1, wherein a general slope of the loading profile is maintained below a predefined maximum threshold.
5. The computer-implemented method of claim 1, wherein a general slope of the loading profile is adjusted using a load extent value if the slope exceeds a predefined maximum threshold.
6. The computer-implemented method of claim 1, wherein the machine implement is a blade and the implement path corresponds to a blade path, the computer-implemented method further engaging control of the blade using the blade path as a lower-bound.
7. The computer-implemented method of claim 6, further enabling sensor-based control of the blade along the blade path such that the blade is automatically raised to a predefined height when a predefined load limit is reached.
8. A control system for determining an implement path for a machine implement at a worksite, comprising:
- a memory configured to retrievably store one or more algorithms; and
- a controller in communication with the memory and, based on the one or more algorithms, configured to at least:
- identify a work surface and a pass target of the worksite;
- define a loading profile based on one or more curves constrained to the work surface and the pass target; and
- define a carry profile based on the loading profile and the pass target.
9. The control system of claim 8, wherein the controller is configured to define the implement path by adjoining the loading profile and the carry profile.
10. The control system of claim 8, wherein the controller is configured to generate one or more of the curves of the loading profile based on a half-Gaussian curve.
11. The control system of claim 8, wherein the controller is configured to constrain the loading profile to be tangent to the adjacent work surface at a start point thereof, and tangent to the adjacent pass target at an end point thereof.
12. The control system of claim 8, wherein the controller is configured to maintain a general slope of the loading profile to be below a predefined maximum threshold.
13. The control system of claim 8, wherein the controller is configured to adjust a general slope of the loading profile according to a load extent value if the slope exceeds a predefined maximum threshold.
14. The control system of claim 8, wherein the machine implement is a blade and the implement path corresponds to a blade path, the controller being configured to engage control of the blade using the blade path as a lower-bound.
15. The control system of claim 14, wherein the controller is configured to enable sensor-based control of the blade along the blade path, and automatically raise the blade to a predefined height when a predefined load limit is detected.
16. A controller for determining an implement path for a machine implement at a worksite, comprising:
- a work surface identification module configured to identify a work surface of the worksite;
- a pass target identification module configured to identify a pass target of the worksite;
- a loading profile module configured to define a loading profile based on one or more curves constrained to the work surface and the pass target; and
- a carry profile module configured to define a carry profile based on the loading profile and the pass target.
17. The controller of claim 16, further comprising an implement path module configured to designate the loading profile and the carry profile as the implement path.
18. The controller of claim 16, wherein the loading profile module is configured to generate one or more of the curves of the loading profile based on a half-Gaussian curve.
19. The controller of claim 16, wherein the loading profile module is configured to constrain the loading profile to be tangent to the adjacent work surface at a start point thereof, and tangent to the adjacent pass target at an end point thereof.
20. The controller of claim 16, wherein the loading profile module is configured to adjust a general slope of the loading profile based on a load extent value if the slope exceeds a predefined maximum threshold.
Type: Application
Filed: Jan 8, 2015
Publication Date: Jul 14, 2016
Inventors: Michael A. Taylor (Swissvale, PA), Thandara K. Edara (Peoria, IL), Mo Wei (Dunlap, IL), Timothy J. Felty (East Peoria, IL)
Application Number: 14/592,684