U.S. patent application number 14/811141 was filed with the patent office on 2017-02-02 for preventive automatic ripping for hard material.
This patent application is currently assigned to Caterpillar Inc.. The applicant listed for this patent is Caterpillar Inc.. Invention is credited to Michael Taylor, Mo Wei.
Application Number | 20170030052 14/811141 |
Document ID | / |
Family ID | 57885887 |
Filed Date | 2017-02-02 |
United States Patent
Application |
20170030052 |
Kind Code |
A1 |
Wei; Mo ; et al. |
February 2, 2017 |
Preventive Automatic Ripping for Hard Material
Abstract
A controller-implemented method for automatically performing
preventive ripping passes using a machine along a work surface is
provided. The controller-implemented method may include defining a
ripper control depth, a minimum control depth, and a maximum
control depth, generating a first ripping pass command for
performing a first ripping pass and a first set of cut commands for
performing a first set of normal cuts, tracking one or more of
machine parameters of the machine and profile parameters of the
work surface to detect failed cuts, and modifying the ripper
control depth by an adjustment value that is determined based on
any detected failed cuts.
Inventors: |
Wei; Mo; (Dunlap, IL)
; Taylor; Michael; (Swissvale, PA) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
Caterpillar Inc. |
Peoria |
IL |
US |
|
|
Assignee: |
Caterpillar Inc.
Peoria
IL
|
Family ID: |
57885887 |
Appl. No.: |
14/811141 |
Filed: |
July 28, 2015 |
Current U.S.
Class: |
1/1 |
Current CPC
Class: |
E02F 9/2041 20130101;
E02F 9/261 20130101; E02F 9/265 20130101; E02F 9/2025 20130101;
E02F 3/7604 20130101; E02F 9/205 20130101; E02F 3/841 20130101;
E02F 9/2045 20130101; E02F 5/32 20130101; E02F 3/844 20130101 |
International
Class: |
E02F 9/20 20060101
E02F009/20; E02F 3/76 20060101 E02F003/76; E02F 5/32 20060101
E02F005/32 |
Claims
1. A controller-implemented method for automatically performing
preventive ripping passes using a machine along a work surface,
comprising: defining a ripper control depth, a minimum control
depth, and a maximum control depth; generating a first ripping pass
command for performing a first ripping pass and a first set of cut
commands for performing a first set of normal cuts; tracking one or
more of machine parameters of the machine and profile parameters of
the work surface to detect failed cuts; and modifying the ripper
control depth by an adjustment value that is determined based on
any detected failed cuts.
2. The controller-implemented method of claim 1, wherein the
initial ripper control depth is defined as the minimum control
depth, and the adjustment value is configured to increment the
ripper control depth by a predetermined fraction of a difference
between the maximum control depth and the minimum control depth if
no failed cuts are detected, and decrement the ripper control depth
by a predetermined fraction of a prior advance depth if a failed
cut is detected.
3. The controller-implemented method of claim 2, wherein the
adjustment value increments the ripper control depth by the
difference between the maximum control depth and the minimum
control depth divided by a number of steps therebetween, each step
having a predefined advance depth.
4. The controller-implemented method of claim 2, wherein the
adjustment value decrements the ripper control depth by
approximately half of a prior advance depth if a failed cut is
detected, decrements the ripper control depth by a prior advance
depth if a failed cut is detected and the machine was stuck, and
decrements the ripper control depth by a maximum missed depth if a
failed cut is detected and the machine was not stuck.
5. The controller-implemented method of claim 1, wherein the first
set of normal cuts is performed until the earliest of when a failed
cut has been detected and the machine is stuck, and when the
maximum control depth has been reached.
6. The controller-implemented method of claim 1, further generating
a second ripping pass command for performing a second ripping pass
according to the modified ripper control depth and a second set of
cut commands for performing a second set of normal cuts.
7. The controller-implemented method of claim 1, wherein the
machine parameters include assessment of any one or more of machine
traction, machine mobility, machine orientation, machine position,
machine speed, and machine operation, and the profile parameters
include assessment of any one or more of a number of normal cuts
performed, a position of a current cut relative to a previous cut,
video feed data, slot geometry, work surface geometry, prior
ripping pass locations, anticipated productivity indices,
predetermined decision rules, and predetermined learning
algorithms.
8. The computer-implemented method of claim 1, wherein the ripping
pass commands are generated as electronic signals configured to
automatically engage the machine to perform the ripping pass
according to a predetermined ripping pass routine, and the machine
parameters and the profile parameters are received as electronic
signals from any one or more of feedback devices, locating devices,
satellites, sensors, and command centers.
9. A control system for automatically performing preventive ripping
passes using a machine along a work surface, 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 define a ripper control
depth, a minimum control depth, and a maximum control depth, issue
a first ripping pass to be performed along the work surface, issue
a first set of normal cuts to be performed after the first ripping
pass, track one or more of machine parameters of the machine and
profile parameters of the work surface to detect failed cuts, and
modify the ripper control depth by an adjustment value that is
determined based on any detected failed cuts.
10. The control system of claim 9, wherein the controller is
configured to define the initial ripper control depth as the
minimum control depth, and define the adjustment value such that
the ripper control depth is incremented by a predetermined fraction
of a difference between the maximum control depth and the minimum
control depth if no failed cuts are detected, and such that the
ripper control depth is decremented by a predetermined fraction of
a prior advance depth if a failed cut is detected.
11. The control system of claim 10, wherein the adjustment value
increments the ripper control depth by the difference between the
maximum control depth and the minimum control depth divided by a
number of steps therebetween, each step having a predefined advance
depth.
12. The control system of claim 10, wherein the adjustment value
decrements the ripper control depth by approximately half of a
prior advance depth if a failed cut is detected, decrements the
ripper control depth by a prior advance depth if a failed cut is
detected and the machine was stuck, and decrements the ripper
control depth by a maximum missed depth if a failed cut is detected
and the machine was not stuck.
13. The control system of claim 9, wherein the controller is
further configured to issue a second ripping pass to be performed
according to the modified ripper control depth, and issue a second
set of normal cuts to be performed after the second ripping
pass.
14. The control system of claim 9, wherein the machine parameters
include assessment of any one or more of loss of traction, machine
mobility, machine orientation, machine position, machine speed, and
machine operation, and the profile parameters include assessment of
any one or more of a number of normal cuts performed, a position of
a current cut relative to a previous cut, video feed data, slot
geometry, work surface geometry, prior ripping pass locations,
anticipated productivity indices, predetermined decision rules, and
predetermined learning algorithms.
15. The control system of claim 9, wherein the controller is
configured to receive the machine parameters and the profile
parameters from any one or more of feedback devices, locating
devices, satellites, sensors, and command centers.
16. A controller for automatically performing preventive ripping
passes using a machine along a work surface, comprising: a control
depth module configured to define at least a ripper control depth,
a minimum control depth, and a maximum control depth; a command
module configured to generate a first ripping pass command for
performing a first ripping pass along the work surface and a first
set of cut commands for performing normal cuts; a tracking module
configured to track one or more of machine parameters of the
machine and profile parameters of the work surface to detect failed
cuts; and an adjustment module configured to modify the ripper
control depth by an adjustment value that is determined by any
detected failed cuts.
17. The controller of claim 16, wherein the control depth module is
configured to define the initial ripper control depth as the
minimum control depth, and the adjustment module is configured to
define the adjustment value such that the ripper control depth is
incremented by a predetermined fraction of a difference between the
maximum control depth and the minimum control depth if no failed
cuts are detected, and such that the ripper control depth is
decremented by a predetermined fraction of a prior advance depth if
a failed cut is detected.
18. The controller of claim 17, wherein the adjustment value
increments the ripper control depth by the difference between the
maximum control depth and the minimum control depth divided by a
number of steps therebetween, each step having a predefined advance
depth.
19. The controller of claim 17, wherein the adjustment value
decrements the ripper control depth by approximately half of a
prior advance depth if a failed cut is detected, decrements the
ripper control depth by a prior advance depth if a failed cut is
detected and the machine was stuck, and decrements the ripper
control depth by a maximum missed depth if a failed cut is detected
and the machine was not stuck.
20. The controller of claim 16, wherein the command module is
further configured to generate a second ripping pass command for
performing a second ripping pass according to the modified ripper
control depth and a second set of cut commands for performing a
second set of normal cuts.
Description
TECHNICAL FIELD
[0001] The present disclosure relates generally to operating
autonomous machines at a work site, and more particularly, to
systems and methods for automatically performing preventive ripping
passes.
BACKGROUND
[0002] Machines 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. The machines may
be manned machines, but may also be semi-autonomous or autonomous
vehicles that perform these tasks in response to commands remotely
or locally generated as part of a work plan for the machines.
Moreover, the machines may receive instructions in accordance with
the work plan to at least partially autonomously perform repetitive
and relatively localized operations such as cutting, digging,
loosening, loading, carrying, and any other manipulation of
materials at the worksite.
[0003] Among other things, autonomous machines, such as dozers, are
frequently used to perform normal cuts along a work surface and in
accordance with predetermined pass or cut profiles. While
performing cuts, however, these machines often encounter sections
of hard material which cannot be cut or removed using the normal
cut routines and blade implements. Such sections of hard material
can cause unwanted interruptions and hinder overall productivity.
If left unattended, for instance, hard materials may leave
undesirable raised surfaces in the terrain that become more
pronounced with every pass, or cause other deviations from the
planned course or target profile. Thus, it is typical for operators
to manually intervene and periodically engage a ripping pass
between normal cuts to loosen the terrain and avoid profile
deviations caused by hard material.
[0004] With the frequency to which such ripping passes are
performed per work site and the frequency to which manual operator
involvement is required by conventional systems, there is a need to
provide a more intuitive and automated approach for minimizing
operator involvement and improving overall efficiency. Some
conventional systems may provide partial automated ripper control,
such as disclosed in U.S. Pat. No. 8,616,297 ("Shintani, et al.").
While automated ripper control may help reduce operator
involvement, the system in Shintani, et al. still requires manual
intervention by the operator to not only identify hard material in
a given terrain, but also to initiate the automated ripping
sequence. Furthermore, schemes as disclosed in Shintani, et al.
still demand frequent interruptions, unwanted delays and a decrease
in overall productivity.
[0005] In view of the foregoing inefficiencies and disadvantages
associated with conventional autonomous machines and control
systems therefor, a need exists for more intuitive automatic
systems and methods which minimize operator involvement and improve
overall efficiency and productivity.
SUMMARY OF THE DISCLOSURE
[0006] In one aspect of the present disclosure, a
controller-implemented method for automatically performing
preventive ripping passes using a machine along a work surface is
provided. The controller-implemented method may include defining a
ripper control depth, a minimum control depth, and a maximum
control depth, generating a first ripping pass command for
performing a first ripping pass and a first set of cut commands for
performing a first set of normal cuts, tracking one or more of
machine parameters of the machine and profile parameters of the
work surface to detect failed cuts, and modifying the ripper
control depth by an adjustment value that is determined based on
any detected failed cuts.
[0007] In another aspect of the present disclosure, a control
system for automatically performing preventive ripping passes using
a machine along a work surface 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.
Based on the one or more algorithms, the controller may be
configured to at least define a ripper control depth, a minimum
control depth, and a maximum control depth, issue a first ripping
pass to be performed along the work surface, issue a first set of
normal cuts to be performed after the first ripping pass, track one
or more of machine parameters of the machine and profile parameters
of the work surface to detect failed cuts, and modify the ripper
control depth by an adjustment value that is determined based on
any detected failed cuts.
[0008] In yet another aspect of the present disclosure, a
controller for automatically performing preventive ripping passes
using a machine along a work surface is provided. The controller
may include a control depth module configured to define at least a
ripper control depth, a minimum control depth, and a maximum
control depth, a command module configured to generate a first
ripping pass command for performing a first ripping pass along the
work surface and a first set of cut commands for performing normal
cuts, a tracking module configured to track one or more of machine
parameters of the machine and profile parameters of the work
surface to detect failed cuts, and an adjustment module configured
to modify the ripper control depth by an adjustment value that is
determined by any detected failed cuts.
BRIEF DESCRIPTION OF THE DRAWINGS
[0009] FIG. 1 is a pictorial illustration of an exemplary
worksite;
[0010] FIG. 2 is a pictorial illustration of a raised surface
disposed along one exemplary work surface at a worksite that may be
caused by a section of hard material;
[0011] FIG. 3 is a diagrammatic illustration of an exemplary
control system that may be used at a worksite to automatically
perform preventive ripping passes;
[0012] FIG. 4 is a diagrammatic illustration of an exemplary
controller of a control system that may be used to automatically
perform preventive ripping passes;
[0013] FIG. 5 is a pictorial illustration of a machine
automatically performing preventive ripping passes along a work
surface; and
[0014] FIG. 6 is a flowchart depicting an exemplary method that may
be performed by a control system or a controller of the present
disclosure to automatically perform preventive ripping passes.
DETAILED DESCRIPTION
[0015] 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.
[0016] 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.
[0017] Referring now to FIG. 1, one exemplary worksite 100 is
illustrated with one or more machines 102 performing predetermined
tasks. The worksite 100 may include, for example, a mine site, a
landfill, a quarry, a construction site, or any other type of
worksite. The predetermined task may be associated with altering
the geography at the worksite 100, such as a dozing operation, a
grading operation, a leveling operation, a bulk material removal
operation, or any other type of operation that results in
geographical modifications within the worksite 100. The machines
102 may be mobile machines configured to perform operations
associated with industries related to mining, construction,
farming, or any other industry known in the art. The machines 102
depicted in FIG. 1, for example, may embody earth moving machines,
such as dozers having fraction devices 104 for causing motion, as
well as implements, such as blades 106 for cutting terrain and
rippers 108 for loosening hard material in terrain, which may be
movable by way of one or more actuators 110. The machines 102 may
also include manned machines or any type of autonomous or
semi-autonomous machine.
[0018] Overall operations of the machines 102 and the machine
implements 106, 108 within the worksite 100 may be managed by a
control system 112 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 114 capable of
signaling, tracking, monitoring, or otherwise communicating
relevant machine parameters or other information to the control
system 112. For example, each machine 102 may include a locating
device 116 configured to communicate with one or more satellites
118, which in turn, may communicate to the control system 112
various parameters and 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 120 configured to track and communicate position
and/or orientation information of the implements 106, 108 to the
control system 112.
[0019] The control system 112 may be implemented in any number of
different arrangements. For example, the control system 112 may be
at least partially implemented at a command center 122 situated
locally and/or remotely relative to the worksite 100 with
sufficient means for communicating with the machines 102, for
example, via satellites 118, or the like. Additionally or
alternatively, the control system 112 may be implemented using one
or more computing devices 124 with means for communicating with one
or more of the machines 102 or one or more command centers 122 that
may be locally and/or remotely situated relative to the worksite
100. In still further alternatives, the control system 112 may be
at least partially 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 112 are possible
and will be understood by those of ordinary skill in the art.
[0020] Using any of the foregoing arrangements, the control system
112 may generally be configured to monitor the positions of the
machines 102 and/or machine implements 106, 108 relative to the
worksite 100 and a predetermined target operation, and provide
instructions for controlling the machines 102 and/or machine
implements 106, 108 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 may include,
among other things, information relating to a location, size and
shape of a plurality of cuts into an intended work surface 126 at
the worksite 100 along a plurality of spaced apart locations
referred to as slots 128. The control system 112 may also function
as a means for monitoring progress of the excavation. For instance,
the control system 112 may oversee gradual changes in the location,
size and shape of the cuts in the work surface 126 within the slots
128 so as to enable identification of any deviations in the
progress of the excavation as compared with the planned target
operation or profile. While described in connection with slot-based
excavation planning, the control system 112 may similarly be
employed in conjunction with other types of work surfaces 126.
[0021] Turning to FIG. 2, one embodiment of a machine 102, such as
a dozer having a blade 106 and a ripper 108, is shown as positioned
on a work surface 126 of a worksite 100 and configured to perform
normal cuts therealong according to a target profile 130. The
machine 102 may be configured to begin cutting and loading material
at positions proximate to the loading area 132 of the work surface
126, and carry the load toward and along the carry surface 134 for
removal. Each normal cut that is performed may be planned to step
through or gradually excavate sections of the work surface 126, for
example, according to the intermediate cut profiles 136 shown.
While performing normal cuts, the machine 102 may encounter
sections of hard material along the work surface 126 which may
hinder the ability of the machine 102 to perform a normal cut as
planned and leave behind unwanted raised surfaces 138 along the
carry surface 134 as shown. Such hard material may be loosened
and/or removed, for instance, by intermittently performing a
ripping pass using a ripper implement 108 of the machine 102.
However, rather than applying such a responsive approach to
performing ripping passes, overall efficiency and productivity may
benefit from more automatic and systematic approaches of performing
preventive ripping passes as disclosed below.
[0022] With reference to FIG. 3, one exemplary embodiment of a
control system 112 that may be used in conjunction with one or more
machines 102 within a worksite 100 to provide optimized and
preventive automatic ripping is diagrammatically illustrated. As
shown, the control system 112 may generally include, among other
things, a controller 140, a memory 142, and a communications device
144. More specifically, the controller 140 may be configured to
operate according to one or more algorithms that are retrievably
stored within the memory 142. The memory 142 may be provided
on-board the controller 140, external to the controller 140, or
otherwise in communication therewith. The communications device 144
may be configured to enable the controller 140 to communicate with
one or more of the machines 102, and provide parameters or
information pertaining to the position and/or orientation of the
machines 102 and the machine implements 106, 108, for example, via
satellites 118, or any other suitable means of communication.
Moreover, the controller 140 may be implemented using any one or
more of a processor, a microprocessor, a microcontroller, or any
other suitable means for executing instructions stored within the
memory 142. Additionally, the memory 142 may include non-transitory
computer-readable medium or memory, such as a disc drive, flash
drive, optical memory, read-only memory (ROM), or the like.
[0023] Referring to FIG. 4, the controller 140 of the control
system 112 may be configured to automatically perform preventive
ripping passes in a manner which reduces interruptions due to
sections of hard material and optimizes overall efficiency and
productivity. Specifically, the controller 140 may be preprogrammed
to operate according to one or more algorithms, which may generally
be categorized into, for example, a control depth module 146, a
command module 148, a tracking module 150, and an adjustment module
152. The control depth module 146 may be configured to define
constraints or parameters that may be used for ripper control, such
as a ripper control depth 154, a minimum control depth 156 and a
maximum control depth 158, as illustrated for example in FIG. 5.
The ripper control depth 154 may correspond to the effective
ripping depth, or the depth through which a single ripping pass is
able to loosen the work surface 126 as well as the target ripping
depth according to which the machine 102 and the ripper 108 is
guided. The minimum control depth 156 may correspond to the depth
that has been substantially cleared of hard material and through
which normal cuts can likely be performed according to plan without
substantial interruptions. The maximum control depth 158 may be
indicative of the maximum depth to which normal cuts may be
performed without requiring a new ripping pass, or the depth beyond
which normal cuts may be subjected to failed cuts due to hard
material.
[0024] The control depth module 146 may initially define one or
more of the ripper control depth 154, the minimum control depth 156
and the maximum control depth 158 prior to beginning work at a new
worksite 100, work surface 126 or slot 128. For example, prior to
performing the initial ripping pass or normal cut, the control
depth module 146 may preliminarily define the ripper control depth
154 as the minimum control depth 156. The control depth module 146
may also define, modify or update one or more of these ripper
control parameters as the machine 102 progresses deeper into a
given work surface 126 or slot 128. For example, the control depth
module 146 may adjust the value of the ripper control depth 154
intermittently, periodically or continuously during each ripping
pass and/or normal cut that is executed within the work surface 126
of FIG. 5. In other embodiments, the control depth module 146 may
adjust or update the ripper control depth 154 after each ripping
pass or normal cut that is executed. Additionally, any one or more
of the ripper control parameters may be defined or adjusted
according to machine parameters associated with the machine 102,
profile parameters associated with the work surface 126 or the work
progress, any manual operator input, or the like.
[0025] The command module 148 of FIG. 4 may be configured to
generate any one or more commands or electronic signals that may be
used to engage the machine 102 and its implements 106, 108 to
perform ripping passes and normal cuts. For example, when an
initial ripping pass should be performed, the command module 148
may generate the appropriate first ripping pass command and
communicate the command to the machine 102 and the appropriate
actuators 110 thereof. Once the first ripping pass has been
completed and/or when one or more normal cuts should be performed,
the command module 148 may then generate a first set of cut
commands and communicate the cut commands to the machine 102 and
its actuators 110. Furthermore, if all of the requested first
ripping pass and the first set of normal cuts have been performed,
and if additional material remains to be removed from the given
slot 128, the command module 148 may be guided by one or more of
the control depth module 146, the tracking module 150 and the
adjustment module 152 to correspondingly generate a second ripping
pass command and a second set of cut commands. The command module
148 may continue in such a manner, for example, until a target
profile 130 is achieved for a given slot 128.
[0026] The tracking module 150 may be configured to intermittently,
periodically or continuously track machine parameters associated
with the machine 102 and/or profile parameters associated with the
work surface 126, and detect for any failed cuts. The tracking
module 150 may receive the machine parameters and/or the profile
parameters from any one or more of the feedback devices 114,
locating devices 116, satellites 118, sensors 120, command centers
122, and the like. Machine parameters may include information
pertaining to traction, mobility, orientation, position, speed,
acceleration, or any other operating parameter of the machine 102.
Profile parameters may include information pertaining to the number
of normal cuts performed, the relative positions of the normal cuts
performed, video feed or sensory data, geometries of the work
surface 126 or slots 128 therein, locations of any previously
performed ripping passes, or the like. Profile parameters may also
include information derived from productivity indices,
preprogrammed decision rules or algorithms, preprogrammed learning
algorithms, or any other guide that may help determine the progress
of the work being performed. Moreover, based on any one or more of
such parameters, the tracking module 150 may be able to detect a
failed cut based on any significant deviations observed between the
actual work progress observed and the target work plan.
[0027] As the machine 102 progresses along a given slot 128, the
adjustment module 152 of FIG. 4 may be configured to modify the
ripper control depth 154 by an adjustment value that is determined
at least partially based on the information tracked and provided by
the tracking module 150. In its simplest form, the adjustment
module 152 may increment or decrement the ripper control depth 154
by predefined adjustment values which effectively cause the machine
102 and the ripper 108 to perform deeper or shallower ripping
passes. Moreover, the adjustment module 152 may opt for deeper or
shallower ripping passes to compensate for any previously detected
failed cuts and to ensure optimized and effective use of each
ripping pass. For instance, if no failed cuts are detected, the
adjustment module 152 may increment the ripper control depth 154 by
an adjustment value to a comparatively deeper depth that
effectively causes the machine 102 and the ripper 108 to loosen the
next layer of potentially hard material. If a failed cut was
detected, however, the adjustment module 152 may decrement the
ripper control depth 154 by an adjustment value to a shallower
depth that aims to loosen the hard material which likely caused the
failed cut. In further modifications, the adjustment module 152 may
further refine the adjustment value based on any other
characteristics observed in relation to the machine 102, the ripper
108, the work surface 126, the slot 128, a detected failed cut, or
the like, as disclosed further below.
[0028] Other variations and modifications of the algorithms or
methods employed to operate the controllers 140 and/or control
systems 112 disclosed herein will be apparent to those of ordinary
skill in the art. One exemplary algorithm or method by which the
controller 140 may be operated to automatically perform preventive
ripping passes using a machine 102 along a work surface 126 is
discussed in more detail below.
INDUSTRIAL APPLICABILITY
[0029] In general terms, the present disclosure sets forth methods,
devices and systems for planned excavations or material moving
operations where there are motivations to improve overall
productivity and efficiency. 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 provides more systematic or automatic means for
performing preventive ripping passes, which clear obstructions and
sections of hard material prior to performing normal cuts. By
performing preventive rather than responsive ripping passes based
on a more intuitive monitoring process, obstructions in the work
surface caused by sections of hard material are more efficiently
and proactively addressed, and the excess time typically spent on
manual correction or other reparative techniques is substantially
reduced.
[0030] One exemplary algorithm or controller-implemented method 160
for automatically performing preventive ripping passes using a
machine 102 along a work surface 126 is diagrammatically provided
in FIG. 6, according to which, for example, the control system 112
or the controller 140 thereof may be configured to operate. As
shown in block 160-1 of FIG. 6, the controller 140 may initially
receive machine parameters associated with the machine 102 and
profile parameters associated with the work surface 126, such as
provided through the communications device 144 and from any of the
feedback devices 114, locating devices 116, satellites 118, sensors
120, command centers 122, and the like. The machine parameters may
include information pertaining to fraction, mobility, orientation,
position, speed, acceleration, or any other operating parameter of
the machine 102. The tracked profile parameters may include
information pertaining to the number of normal cuts performed, the
relative positions of the normal cuts performed, video feed or
other sensory data, geometries of the work surface 126 or slots 128
therein, locations of any previously performed ripping passes, or
the like. The profile parameters may also include any information
derived from anticipated productivity indices, preprogrammed
decision rules or algorithms, preprogrammed learning algorithms, or
any other parameter that may be used to track work progress.
[0031] As shown in block 160-2 of FIG. 6, the controller 140 may
also define one or more constraints or parameters that may be used
for ripper control, such as the ripper control depth 154, the
minimum control depth 156 and the maximum control depth 158 as
illustrated for example in FIG. 5. The controller 140 may define
the ripper control depth 154 according to the effective ripping
depth, or the depth through which a single ripping pass is expected
to loosen the work surface 126. The controller 140 may define the
minimum control depth 156 as the depth that is expected to be
substantially clear of hard material and through which normal cuts
can likely be performed according to plan without substantial
interruptions. The controller 140 may define the maximum control
depth 158 as the maximum depth beyond which the machine 102 should
not progress without first performing a new ripping pass. The
controller 140 may operate the machine 102 and the ripper implement
108 to perform ripping passes and normal cuts using one or more of
the ripper control depth 154, the minimum control depth 156 and the
maximum control depth 158 as guidance. It will be understood that
other variables, constraints or parameters may also be implemented
and used by the controller 140 to control the machine 102 and/or
the ripper 108.
[0032] Upon reaching a new work surface 126 or slot 128 and before
performing a first ripping pass, the controller 140 may initially
set one or more of the ripper control depth 154, the minimum
control depth 156 and the maximum control depth 158 to predefined
default values. For example, prior to performing the initial
ripping pass or normal cut, the controller 140 may preliminarily
define the ripper control depth 154 as the minimum control depth
156. As the machine 102 progresses deeper into the work surface 126
or slot 128, the controller 140 may redefine, modify or update one
or more of the ripper control parameters based on changes observed
in the machine 102 and/or the work surface 126. For instance, the
controller 140 may adjust or update the value of the ripper control
depth 154 intermittently, periodically or continuously as the
machine 102 performs the ripping passes and/or the normal cut
operations, and as the geometry of the work surface 126 is changed
thereby. In other embodiments, the controller 140 may adjust or
update the ripper control depth 154 once after each ripping pass or
series of normal cuts are executed within the given work surface
126. Additionally, any one or more of the ripper control parameters
may be defined or adjusted based on machine parameters associated
with the machine 102, profile parameters associated with the work
surface 126, manual overrides via operator input, or the like.
[0033] As shown in block 160-3 of FIG. 6, the controller 140 may
generate a first ripping pass command based on the ripper control
parameters defined in block 160-2. More specifically, the
controller 140 may generate and communicate to the machine 102 one
or more electronic signals configured to engage the machine 102 and
the appropriate actuators 110 thereof to perform a ripping pass
along the work surface 126. As the machine 102 performs the first
ripping pass, the controller 140 may continue monitoring the
machine parameters and/or the profile parameters as in block 160-1.
Once the machine parameters and/or the profile parameters suggest
that the first ripping pass is complete, the controller 140 in
block 160-4 may generate a first set of cut commands which may also
be determined based on the ripper control parameters defined in
block 160-2. For example, the controller 140 may generate and
communicate to the machine 102 one or more electronic signals
configured to engage the machine 102 and the appropriate actuators
110 thereof to perform a series of normal cuts through the ripped
work surface 126. As the machine 102 performs the first set of
normal cuts, the controller 140 may also monitor the machine
parameters and/or the profile parameters to ensure that the machine
102 does not perform normal cuts beyond the maximum control depth
or beyond the target profile 130 for the given slot 128.
[0034] While the machine 102 performs the first set of normal cuts,
the controller 140 may additionally monitor and track the machine
parameters and/or profile parameters for any failed cuts as shown
in blocks 160-5 and 160-6 of FIG. 6. Specifically, the controller
140 may intermittently, periodically or continuously track the
actual progress of the machine 102 and/or work surface 126 or slot
128 to determine whether there are any significant deviations
between the actual work progress and the target work plan. For
example, although relatively insignificant deviations may be normal
and permissible, more significant deviations may suggest sections
of hard material in the work surface 126 in need of a ripping pass.
Moreover, the controller 140 may generally be preprogrammed with
threshold values that render the controller 140 relatively more
sensitive to failed cuts such that resulting ripping passes are
more preventive than reparative. Furthermore, in one embodiment,
the controller 140 may track and detect failed cuts as they are
encountered during, before or after each normal cut that is
performed. In other embodiments, the controller 140 may make a
cumulative determination and compare the actual work progress to
the target work plan after the first set of normal cuts is
complete. Other arrangements may also be implemented to achieve
comparative results.
[0035] Once the first series of normal cuts is complete, and if no
failed cuts are detected, the controller 140 may update or
increment the ripper control depth 154 by an adjustment value as
shown in block 160-7 of FIG. 6 so as to prepare the machine 102 for
a new iteration of the method 160, such as a second ripping pass
and a second set of normal cuts. The controller 140 may define the
adjustment value as a predetermined fraction of the difference
between the maximum control depth 158 and the minimum control depth
156 defined in block 160-2. The predetermined fraction may be fixed
or determined based on the number of cuts or steps between the
minimum control depth 156 and the maximum control depth 158, where
each step has a known or predefined advance depth. In block 160-8
of FIG. 6 for instance, the adjustment value may be configured to
increment the ripper control depth 154 by the difference between
the minimum control depth 156 and the maximum control depth 158,
divided by the number of steps therebetween. The controller 140 may
further update the minimum control depth 156 and the maximum
control depth 158 according to the updated ripper control depth
154, and apply the updated ripper control parameters for subsequent
iterations as necessary. Furthermore, each of the ripper control
parameters may be updated to the extent allowed by the work plan,
or more particularly, so that the machine 102 does not perform
ripping passes or normal cuts beyond the target profile 130.
[0036] If, however, one or more failed cuts are detected in block
160-6, the controller 140 may decrement the ripper control depth
154 by an adjustment value as shown in block 160-9 of FIG. 6. More
specifically, the controller 140 may recognize that a failed cut
suggests sections of hard material in the work surface 126 that can
potentially cause significant delays and setbacks if left
untreated. Accordingly, the controller 140 in block 160-9 may
adjust the ripper control depth 154 in a manner which causes the
machine 102 to automatically perform a preventive ripping pass and
clear any hard material or other obstacles in the work surface 126
before proceeding further. As shown in block 160-10 of FIG. 6, the
controller 140 may define the adjustment value such that the ripper
control depth 154 is decremented or raised by at least half of a
prior advance depth, or the depth the machine 102 was advanced in
the most recent normal cut operation. By decrementing the ripper
control depth 154, the controller 140 may be able to cause the
machine 102 and the ripper 108 to perform a subsequent or second
ripping pass that is more focused on sections within the work
surface 126 where hard material likely reside. In other
embodiments, the controller 140 may decrement the ripper control
depth 154 by other adjustment values that are fixed, determined
based on one or more machine parameters and/or profile parameters,
or the like.
[0037] As shown in block 160-11 of FIG. 6, the controller 140 may
further vary the adjustment value based on the type or magnitude of
the failed cut detected. For instance, if the machine parameters
associated with the machine 102 and/or the profile parameters
associated with the work surface 126 indicate that there was a
failed cut, but do not indicate any signs of the machine 102 being
stuck at any point during the normal cut operation, the controller
140 may set the adjustment value to the default value of
approximately half of the prior advance depth as in block 160-10,
or alternatively, set the adjustment value to the approximate
maximum depth of the missed cut as in block 160-12. If, however,
the machine parameters associated with the machine 102 indicate
that the machine 102 is or was stuck during any point while
performing a normal cut, the controller 140 may determine that
there is a greater amount of hard material in the work surface 126
and decrement the ripper control depth 154 by more than the default
adjustment value. As shown in block 160-13 for example, the
controller 140 may set the adjustment value to approximately the
entire prior advance depth rather than the default value of
approximately half of the prior advance depth of block 160-10.
[0038] In other embodiments, the controller 140 in block 160-11 may
additionally or alternatively detect for indications, other than
whether the machine 102 was stuck, to gauge the severity of a
failed cut. In still further modifications, the controller 140 may
decrement the ripper control depth 154 to other adjustment values
that are fixed, determined based on one or more machine parameters
and/or profile parameters, or the like. Based on the updated ripper
control depth 154, the controller 140 may further update the
minimum control depth 156 and the maximum control depth 158
accordingly, and apply the decremented ripper control parameters
for a subsequent or a second iteration as necessary. Furthermore,
the ripper control parameters may be updated to the extent allowed
by the work plan, or more particularly, so that the machine 102
does not perform ripping passes or normal cuts beyond or deeper
than the target profile 130. Additionally, if the machine
parameters and/or profile parameters indicate that the target
profile 130 for the given slot 128 has already been achieved upon
completion of the first set of normal cuts, the controller 140 may
omit any one or more of the processes following block 160-5 and
return to block 160-1. Although the method 160 of FIG. 6
illustrates one possible iteration for automatically performing
preventive ripping passes, it will be understood that other
arrangements are capable producing comparative results. In
addition, any one or more of the block functions disclosed in FIG.
6 may be omitted, combined with other block functions, or performed
in sequences other than as illustrated.
[0039] 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.
* * * * *