U.S. patent application number 14/506915 was filed with the patent office on 2016-04-07 for system and method for monitoring position of machine implement.
This patent application is currently assigned to Caterpillar Inc.. The applicant listed for this patent is Caterpillar Inc.. Invention is credited to Paul R. Friend, Karl A. Kirsch.
Application Number | 20160097183 14/506915 |
Document ID | / |
Family ID | 55632432 |
Filed Date | 2016-04-07 |
United States Patent
Application |
20160097183 |
Kind Code |
A1 |
Kirsch; Karl A. ; et
al. |
April 7, 2016 |
SYSTEM AND METHOD FOR MONITORING POSITION OF MACHINE IMPLEMENT
Abstract
A system for monitoring a position of an implement of a motor
grader relative to a frame thereof is provided. The motor grader
includes an actuation system to selectively move the implement
relative to the frame. The system includes a fiber optic cable
extending along at least a portion of the frame, a portion of the
actuation system and a portion of the implement. The fiber optic
cable is configured to move with the portion of the actuation
system and the portion of the implement, and selectively generate
signals indicative of a shape thereof. The system further includes
a controller in communication with the fiber optic cable. The
controller is configured to determine the shape of the fiber optic
cable based on the signals received therefrom, and further
determine a position of the implement relative to the frame based
on the shape of the fiber optic cable.
Inventors: |
Kirsch; Karl A.;
(Chillicothe, IL) ; Friend; Paul R.; (Morton,
IL) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
Caterpillar Inc. |
Peoria |
IL |
US |
|
|
Assignee: |
Caterpillar Inc.
Peoria
IL
|
Family ID: |
55632432 |
Appl. No.: |
14/506915 |
Filed: |
October 6, 2014 |
Current U.S.
Class: |
701/50 |
Current CPC
Class: |
E02F 3/764 20130101;
E02F 3/847 20130101; E02F 3/7645 20130101; E02F 3/765 20130101 |
International
Class: |
E02F 3/84 20060101
E02F003/84; E02F 3/76 20060101 E02F003/76 |
Claims
1. A system for monitoring a position of an implement of a motor
grader relative to a frame of the motor grader, the motor grader
having an actuation system configured to selectively move the
implement relative to the frame, the system comprising: a fiber
optic cable extending along at least a portion of the frame, a
portion of the actuation system and a portion of the implement,
wherein the fiber optic cable is configured to move with the
portion of the actuation system and the portion of the implement,
and wherein the fiber optic cable is further configured to
selectively generate signals indicative of a shape thereof; and a
controller in communication with the fiber optic cable, wherein the
controller is configured to determine the shape of the fiber optic
cable based on the signals received therefrom, and wherein the
controller is further configured to determine a position of the
implement relative to the frame based on the shape of the fiber
optic cable.
2. The system of claim 1, the fiber optic cable comprising at least
one core and a plurality of strain sensors distributed along a
length of the at least one core.
3. The system of claim 2, wherein each of the plurality of strain
sensors is one of a Fiber Bragg Grating (FBG) sensor and Rayleigh
Scatter Detector.
4. The system of claim 1, wherein the controller is further
configured to regulate the actuation system to move the implement
based on at least a user input and the position of the
implement.
5. The system of claim 1, wherein the controller is further
configured to transmit an optical signal to the fiber optic
cable.
6. The system of claim 1 further comprising mechanical fasteners
configured to couple the fiber optic cable to at least the frame,
the actuation system and the implement.
7. A motor grader comprising: a frame; an implement movable
relative to the frame; an actuation system coupled to the frame and
the implement, the actuation system configured to selectively move
the implement relative to the frame; a fiber optic cable extending
along at least a portion of the frame, a portion of the actuation
system and a portion of the implement, wherein the fiber optic
cable is configured to move with the portion of the actuation
system and the portion of the implement, and wherein the fiber
optic cable is further configured to selectively generate signals
indicative of a shape thereof; and a controller in communication
with the fiber optic cable, wherein the controller is configured to
determine the shape of the fiber optic cable based on the signals
received therefrom, and wherein the controller is further
configured to determine a position of the implement relative to the
frame based on the shape of the fiber optic cable.
8. The motor grader of claim 7, the fiber optic cable comprising at
least one core and a plurality of strain sensors distributed along
a length of the at least one core.
9. The motor grader of claim 8, wherein each of the plurality of
strain sensors is one of a Fiber Bragg Grating (FBG) sensor and
Rayleigh Scatter Detector.
10. The motor grader of claim 7, wherein the controller is further
configured to regulate the actuation system to move the implement
based on at least a user input and the position of the
implement.
11. The motor grader of claim 7, wherein the controller is further
configured to transmit an optical signal to the fiber optic
cable.
12. The motor grader of claim 7, further comprising mechanical
fasteners configured to couple the fiber optic cable to at least
the frame, the actuation system and the implement.
13. The motor grader of claim 7, wherein the actuation system
comprising: a drawbar member movably coupled to the frame; and a
circle member rotatably coupled to the drawbar member, the circle
member comprising an arm portion pivotally coupled to the
implement.
14. The motor grader of claim 13, wherein the fiber optic cable
extends along a portion of the drawbar member and a portion of the
circle member.
15. The motor grader of claim 13, wherein the actuation system
further comprising: a support member coupled to the frame; a first
linear actuator coupled to the support member and the drawbar
member, the first linear actuator configured to move the drawbar
member along a first axis; a second linear actuator coupled to the
support member and the drawbar member, the second linear actuator
configured to move the drawbar member along a second axis
perpendicular to the first axis; and a rotary actuator coupled to
the circle member, the rotary actuator configured to rotate the
circle member about the first axis.
16. The motor grader of claim 15, wherein the fiber optic cable
extends along a portion of the support member, a portion of the
first linear actuator, a portion of the drawbar member and a
portion of the circle member.
17. The motor grader of claim 15, wherein the actuation system
further comprising: a third linear actuator coupled to the circle
member and the implement, the third linear actuator configured to
rotate the implement relative to the arm portion of the circle
member about the second axis; and a fourth linear actuator coupled
to the circle member and the implement, the fourth linear actuator
configured to slide the implement relative to arm portion the along
the second axis.
18. The motor grader of claim 17, wherein the fiber optic cable is
coupled to the fourth linear actuator.
19. A method of monitoring a position of an implement of a motor
grader relative to a frame of the motor grader, the motor grader
having an actuation system configured to selectively move the
implement relative to the frame, the method comprising: providing a
fiber optic cable along at least a portion of the frame, a portion
of the actuation system and a portion of the implement, wherein the
fiber optic cable is configured to move with the portion of the
actuation system and the portion of the implement; receiving
signals from the fiber optic cable, wherein the signals are
indicative of a shape of the fiber optic cable; determining the
shape of the fiber optic cable based on the received signals; and
determining a position of the implement relative to the frame based
on the shape of the fiber optic cable.
20. The method of claim 19, further comprising transmitting an
optical signal to the fiber optic cable.
Description
TECHNICAL FIELD
[0001] The current disclosure relates to an implement of a machine,
and more particularly to a system and a method of monitoring a
position of an implement of a motor grader.
BACKGROUND
[0002] A motor grader typically includes a front frame and a rear
frame. An engine and a transmission system are disposed in the rear
frame, while an operator cab is disposed in the front frame. The
front frame also includes a beam to support an implement. A
position and an orientation of the implement relative to the front
frame are regulated by a drawbar, a circle member and multiple
cylinders. The drawbar is supported on the beam, and moved in
vertical and horizontal directions relative to the front frame via
hydraulic cylinders. The circle member is attached to the drawbar.
The circle member is allowed to rotate relative to the drawbar via
a motor. The implement is coupled to the circle member through a
retainer. Hydraulic cylinders further control linear movement and
angular movement of the implement relative to the circle member.
The position and orientation of the implement along with those of
the various actuation elements, including the drawbar and the
circle member, may have to be monitored for precise control of the
implement.
[0003] U.S. Pat. No. 8,478,492 (the '492 patent) discloses a method
and a system for performing non-contact based determination of the
position of an implement. The '492 patent includes a non-contact
based measurement system to determine the relative position of an
implement coupled with a mobile machine. The geographic position of
the mobile machine is determined based on a satellite based
position determination system. The geographic position of the
implement is determined based upon the geographic position of the
mobile machine. Hence, the position of the implement is determined
relative to the mobile machine.
[0004] Fiber optic shape sensing is known in the art. For example,
a system for sensing fiber optic shape is disclosed in US Patent
Publication Number 2013/0308138. The patent includes a fiber optic
cable having one or more cores. An optical interrogation console
generates reflection spectrum data indicative of a measurement of
both amplitude and a phase of a reflection for each core as a
function of wavelength. A 3D shape reconstructor reconstructs a 3D
shape of the optical fiber.
SUMMARY OF THE DISCLOSURE
[0005] In one aspect of the current disclosure, a system for
monitoring a position of an implement of a motor grader relative to
a frame of the motor grader is provided. The motor grader includes
an actuation system configured to selectively move the implement
relative to the frame. The system includes a fiber optic cable
extending along at least a portion of the frame, a portion of the
actuation system and a portion of the implement. The fiber optic
cable is configured to move with the portion of the actuation
system and the portion of the implement. The fiber optic cable is
further configured to selectively generate signals indicative of a
shape thereof. The system further includes a controller in
communication with the fiber optic cable. The controller is
configured to determine the shape of the fiber optic cable based on
the signals received therefrom. The controller is further
configured to determine a position of the implement relative to the
frame based on the shape of the fiber optic cable.
[0006] In another aspect of the current disclosure, a motor grader
is provided. The motor grader includes a frame and an implement
movable relative to the frame. The motor grader includes an
actuation system coupled to the frame and the implement. The
actuation system is configured to selectively move the implement
relative to the frame. The motor grader further includes a fiber
optic cable extending along at least a portion of the frame, a
portion of the actuation system and a portion of the implement. The
fiber optic cable is configured to move with the portion of the
actuation system and the portion of the implement. The fiber optic
cable is further configured to selectively generate signals
indicative of a shape thereof. The motor grader further includes a
controller in communication with the fiber optic cable. The
controller is configured to determine the shape of the fiber optic
cable based on the signals received therefrom. The controller is
further configured to determine a position of the implement
relative to the frame based on the shape of the fiber optic
cable.
[0007] In yet another aspect of the current disclosure, a method of
monitoring a position of an implement of a motor grader relative to
a frame of the motor grader is provided. The motor grader includes
an actuation system configured to selectively move the implement
relative to the frame. The method includes providing a fiber optic
cable along at least a portion of the frame, a portion of the
actuation system and a portion of the implement. The fiber optic
cable is configured to move with the portion of the actuation
system and the portion of the implement. The method further
includes receiving signals from the fiber optic cable. The signals
are indicative of a shape of the fiber optic cable. The method also
includes determining the shape of the fiber optic cable based on
the received signals. The method further includes determining a
position of the implement relative to the frame based on the shape
of the fiber optic cable.
[0008] Other features and aspects of this disclosure will be
apparent from the following description and the accompanying
drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
[0009] FIG. 1 is a side view of a motor grader, according to an
aspect of the current disclosure;
[0010] FIG. 2 is a perspective view of an actuation system of the
motor grader and a system for monitoring a position of an implement
associated with the actuation system, according to an aspect of the
current disclosure;
[0011] FIG. 3 is a sectional perspective view of a fiber optic
cable of the system, according to an exemplary aspect of the
current disclosure;
[0012] FIG. 4 is a perspective view of an arrangement of the fiber
optic cable to determine a position of the implement, according to
another aspect of the current disclosure;
[0013] FIG. 5 is a block diagram illustrating the system for
determining the position of the implement, according to an aspect
of the current disclosure;
[0014] FIG. 6 is an output of the system showing the position of
the implement of FIG. 2, according to an aspect of the current
disclosure;
[0015] FIG. 7 is an output of the system showing another position
of the implement; and
[0016] FIG. 8 is a flowchart of a method of determining the
position of the implement, according to an aspect of the current
disclosure.
DETAILED DESCRIPTION
[0017] Reference will now be made in detail to specific aspects or
features, examples of which are illustrated in the accompanying
drawings. Wherever possible, corresponding or similar reference
numbers will be used throughout the drawings to refer to the same
or corresponding parts.
[0018] FIG. 1 shows a side view of a motor grader 100, according to
an aspect of the current disclosure. The motor grader 100 may be
used to level a surface of a ground. The motor grader 100 may
include a frame. The frame may include a front frame 102 and a rear
frame 104 coupled with the front frame 102. The front frame 102 may
be pivotally coupled with the rear frame 104 such that the front
frame 102 may rotate relative to the rear frame 104. In another
aspect of the current disclosure, the motor grader 100 may include
a single frame. The front frame 102 and the rear frame 104 may be
supported on ground engaging members 107. The front frame 102 may
include a beam 105 having a front end 111 coupled with the ground
engaging members 107 and a rear end 109 pivotally coupled with the
rear frame 104. In another aspect of the current disclosure, the
ground engaging member 107 coupled with the front frame 102 may
include an axle having both ends rotatably coupled with wheels.
Similarly, the ground engaging members 107 coupled with the rear
frame 104 may include one or more axles having both ends rotatably
coupled with wheels. Alternatively, the ground engaging members 107
may be tracks.
[0019] The motor grader 100 may further include an implement 106
for performing various earth moving operations, such as ground
levelling. The implement 106 may be disposed in the front frame
102. Specifically, the implement 106 may be supported on the beam
105. The implement 106 may include a blade 108 configured to be in
contact with a surface of the ground. The motor grader 100 may
further include a power source (not shown) to supply power to
various components including, but not limited to, the ground
engaging members 107 and the implement 106. In another aspect of
the current disclosure, the power source may be an engine. The
engine may be disposed in the rear frame 104. In another aspect of
the current disclosure, the power source may include a battery, a
fuel cell or any other electrical power storage device known in the
art. The engine may drive the ground engaging members 107 via a
transmission (not shown). The transmission may produce multiple
output speed ratios or a continuously variable speed ratio between
the engine and the ground engaging member 107. Further, an operator
cab 110 may be supported on the front frame 102. The operator cab
110 may include various operator controls, along with displays or
indicators used to drive the motor grader 100 and convey
information to an operator.
[0020] FIG. 2 shows a perspective view of an actuation system 112
of the motor grader 100. The actuation system 112 may be configured
to selectively move the implement 106 relative to the front frame
102. In another aspect of the current disclosure, a system 114 may
be further associated with the actuation system 112 for monitoring
a position of the implement 106. The actuation system 112 may
include a drawbar member 120 movably coupled to the beam 105. The
drawbar member 120 may include a first leg 122, a second leg 124
and a third leg 126. Ends of the first leg 122 and the second leg
124 may be connected to a bracket 127 disposed on the beam 105. The
other ends of the first leg 122 and the second leg 124 may be
connected proximate to a first end and a second end of the third
leg 126, respectively. Thus, the drawbar 120 may define a tapered
end 128 and a base end 130 distal from the tapered end 128. The
tapered end 128 of the drawbar member 120 may be pivotally coupled
to the front end 111 of the beam 105 via a joint, for example, a
ball and socket joint. Hence, the drawbar member 120 may have
multiple degrees of freedom of movement with respect to the front
frame 102.
[0021] The drawbar 120 may include a yoke plate 158 adjacent to the
base end 130. A circle member 160 may be rotatably coupled to the
yoke plate 158. The circle member 160 may include an outer
circumference 162 and an inner circumference 163. The circle member
160 may further include an arm portion 164 extending from the outer
circumference 162. The arm portion 164 may extend towards the
implement 106. Further, the arm portion 164 may be pivotally
coupled to the implement 106. The circle member 160 may be further
operatively coupled with a rotary actuator 161 (shown in FIG. 1).
The rotary actuator 161 may be an electric motor or a hydraulic
motor. The rotary actuator 161 may include a gear configured to
engage with teeth (not shown) provided on the inner circumference
163 of the circle member 160. Further, the rotary actuator 161 may
be mounted on the yoke plate 158 to engage with the circle member
160. The rotary actuator 161 may facilitate rotation of the circle
member 160 about a first axis A1. Hence, the implement 106 may also
be rotated about the first axis A1 substantially perpendicular to a
plane of the yoke plate 158.
[0022] As shown in FIG. 2, the base end 130 of the drawbar member
120 may be coupled to the beam 105 via a support member 132. The
support member 132 may be movably mounted on the beam 105. Further,
the support member 132 may include a first lift arm 136 and a
second lift arm 138. The first lift arm 136 and the second lift arm
138 may be pivotally coupled to the support member 132.
Specifically, the first lift arm 136 may be pivotally coupled to
one side of the beam 105 and the second lift arm 138 may be
pivotally coupled to another side of the beam 105 opposite to the
first lift arm 136. Each of the first and the second lift arms 136,
138 may include a leg 140 that may extend towards the drawbar
member 120. A free end of the legs 140 may be coupled with a length
adjusting member 142. The length adjusting member 142 may include a
plurality of mounting holes 144 distributed along a length thereof.
The free ends of the legs 140 may be coupled to any one of the
mounting holes 144 in order to adjust a position of the first and
second lift arms 136, 138.
[0023] A first linear actuator 146 may couple each of the first
lift arm 136 and the second lift arm 138 to the base end 130 of the
drawbar member 120. The first linear actuator 146 may be configured
to move the drawbar member 120 along the first axis A1. In another
aspect of the current disclosure, the first linear actuator 146 may
be actuated by a hydraulic system (not shown) of the motor grader
100. The first linear actuator 146 may include a cylinder 152 and a
piston rod 154 slidably disposed within the cylinder 152. The
cylinder 152 may be coupled with the first lift arm 136 and the
piston rod 154 may be coupled to the first end of the third leg
126. In another aspect of the current disclosure, the first linear
actuator 146 may be a double acting cylinder. In such a case, a
head end and a rod end of the cylinder 152 defined by the piston
rod 154 may be in fluid communication with the hydraulic system. In
another aspect of the current disclosure, the first linear actuator
146 may be a single acting cylinder. In such a case, the head end
of the cylinder 152 may be in fluid communication with the
hydraulic system.
[0024] In an exemplary aspect of the current disclosure, the
hydraulic system of the motor grader 100 may include a pump (not
shown) drivably coupled to the power source to supply pressurized
fluid to the first linear actuator 146 from a fluid reservoir (not
shown). The fluid reservoir may be disposed in the rear frame 104.
The hydraulic system may further include one or more control valves
to regulate supply of pressurized fluid to the first linear
actuator 146. The control valves may be regulated by a controller
150 of the motor grader 100 based upon input signals from an
operator controlled device. The first linear actuator 146 may be
actuated by the hydraulic system to move the drawbar 120 upwards or
downwards along the first axis A1. Hence, the implement 106 may
also be moved along the first axis A1 with respect to the front
frame 102.
[0025] The base end 130 of the drawbar member 120 may be further
coupled to the support member 132 via a second linear actuator 156.
The second linear actuator 156 may be configured to move the
drawbar member 120 along a second axis A2 substantially
perpendicular to the first axis A1. The second linear actuator 156
may be a hydraulic cylinder similar to the first linear actuator
146. One end of the second linear actuator 156 may be coupled to
any one of the plurality of mounting holes 144 of the length
adjusting member 142 and another end may be coupled adjacent to the
second end of the third leg 126. The second linear actuator 156 may
also be coupled to the hydraulic system similar to the first linear
actuator 146. Thus, the second linear actuator 156 may be actuated
to move the base end 130 along the second axis A2. Hence, the
implement 106 may also be moved along the second axis A2 with
respect to the front frame 102.
[0026] As shown in FIG. 2, the implement 106 includes the blade 108
and blade rails 103 coupled to the blade 108. The blade rails 103
may be further slidably coupled to a retainer 172. Further, the
retainer 172 may be pivotally coupled to the arm portion 164 of the
circle member 160. Further, the retainer 172 may be coupled to the
circle member 160 via a third linear actuator 174. The third linear
actuator 174 may be a hydraulic cylinder similar to the first
linear actuator 146. One end of the third linear actuator 174 may
be coupled to the retainer 172 and another end may be coupled to
the circle member 160 to rotate the implement 106 relative to the
arm portion 164 about the second axis A2. The third linear actuator
174 may also be coupled to the hydraulic system similar to the
first linear actuator 146.
[0027] The actuation system 112 may further include a fourth linear
actuator 180 received within the retainer 172. The fourth linear
actuator 180 may be configured to slide the implement 106 relative
to the retainer 172 along the second axis A2. The fourth linear
actuator 180 may be a hydraulic cylinder similar to the first
linear actuator 146. The fourth linear actuator 180 may include a
cylinder 182 mounted on the retainer 172 and a piston rod 184
slidably disposed within the cylinder 182. The fourth linear
actuator 180 may be coupled to the hydraulic system similar to the
first linear actuator 146. Thus, the fourth linear actuator 180 may
be actuated to linearly move the blade 108 along the second axis A2
relative to the retainer 172 and the arm portion 164.
[0028] As shown in FIG. 2, the system 114 may include a fiber optic
cable 302. The fiber optic cable 302 may extend along at least a
portion of the front frame 102, a portion of the actuation system
112 and a portion of the implement 106. Further, the fiber optic
cable 302 may be configured to move with the portion of the
actuation system 112 and the portion of the implement 106. The
portions of the front frame 102, the actuation system 112 and the
implement 106 are described hereinafter in detail. The fiber optic
cable 302 may include a first end 304 (shown in FIG. 3). In another
aspect of the current disclosure, the first end 304 may be disposed
at any position on the beam 105. The fiber optic cable 302 may then
extend to the first leg 122 of the drawbar member 120 and coupled
along a surface 305 of the first leg 122. Thus, the fiber optic
cable 302 extends along a portion of the drawbar member 120.
Specifically, the fiber optic cable 302 may extend to the second
leg 124 of the drawbar member 120 and coupled along a surface of
the second leg 124. The fiber optic cable 302 may be then coupled
with the third leg 126 and extend to a center of the third leg 126.
In the illustrated aspect of the current disclosure, the fiber
optic cable 302 may then extend through the circle member 160,
substantially along the axis A1, from the center of the third leg
126. The fiber optic cable 302 may then travel along the arm
portion 164 and coupled thereto. Alternatively, the fiber optic
cable 302 may extend perpendicularly from the center of the third
leg 126 and may be coupled with the outer circumference 162 of the
circle member 160.
[0029] The fiber optic cable 302 may be coupled along a surface 314
of the arm portion 164. The fiber optic cable 302 may then travel
to a bottom end 316 of the arm portion 164. Thus, the fiber optic
cable 302 may extend along a portion of the circle member 160. From
the bottom end 316, the fiber optic cable 302 may be wound around
the piston rod 184 of the fourth linear actuator 180 and extend to
a location 318 where the piston rod 184 is mounted on the blade
108. In another aspect of the current disclosure, the fiber optic
cable 302 may further travel along the blade 108 and coupled
thereto. The fiber optic cable 302 may be further configured to
selectively generate signals indicative of a shape thereof.
[0030] In another aspect of the current disclosure, the fiber optic
cable 302 extending between the first end 304 and a second end 306
may include multiple fiber optic cables 302. The multiple fiber
optic cables 302 may be coupled each other via various methods
known in the art, such as fusion splicing, and mechanical
connectors etc. Further, the fiber optic cable 302 may be coupled
to the various components of the actuation system 112 and the beam
105 by mechanical fasteners 310, such as clamps, clips, and the
like. Further, in various aspects of the current disclosure, the
fiber optic cable 302 may also be embedded at least partially in
one or more components.
[0031] FIG. 3 illustrates a sectional perspective view of the fiber
optic cable 302, according to an aspect of the current disclosure.
The fiber optic cable 302 may extend between the first end 304 and
the second end 306 defining a length `L` therebetween. The fiber
optic cable 302 may further include at least one core 210 that may
extend between the first end 304 and the second end 306 of the
fiber optic cable 302. The core 210 may be configured to be a
light-carrying element. Although the fiber optic cable 302, in the
illustrated aspect of the current disclosure, includes one core
210, it may be contemplated that the system 114 may include a fiber
optic cable having multiple cores.
[0032] The core 210 may be further surrounded by a layer 218 of
cladding 212. A material of the core 210 and the cladding 212 may
be a polymer, such as polystyrene, PMMA, or the like known in the
art. The material used for making the core 210 may have a high
transparency and the material used for the cladding 212 may have a
refractive index lower than the material of the cores 210. A
difference between the refractive indices between the core 210 and
the cladding 212 may provide total internal reflection of light
transmitted within the core 210.
[0033] The fiber optic cable 302 may further include a plurality of
strain sensors 214 distributed along a length of the core 210. Each
of the plurality of strain sensors 214 may be disposed in the core
210 such that a distance between every adjacent strain sensors 214
may be kept substantially equal. Each of the strain sensors 214 may
be, for example, a Fiber Bragg Gratings (FBGs) or a Rayleigh
Scatter Detector. The strain sensors 214 may be further configured
to estimate bending and/or twisting of the fiber optic cable 302 at
each location of the strain sensor 214. The strain sensors 214 may
be configured to communicate with the controller 150.
[0034] Further, a layer 218 made from a polymer may be bonded to
the cladding 212. The layer 218 may act as a protective coating.
More specifically, the layer 218 may act as shock absorber to
protect the core 210 and the cladding 212 from damage. The layer
218 may be further surrounded by a sleeve 220 that may be made from
a reinforcing polymeric material, such as aramid.
[0035] Specifically, the sleeve 220 may surround the cladding 212
along the length `L` of the fiber optic cable 302. In another
aspect of the current disclosure, an outer surface of the layer 218
and an inner surface of the sleeve 220 may not be bonded, adhered,
or otherwise attached to each other. Hence, the cladding 212 and
the core 210 may rotate freely or twist within the sleeve 220 with
minimal or no friction. In another aspect of the current
disclosure, the sleeve 220 may be bonded to the layer 218.
[0036] The fiber optic cable 302, shown in FIG. 2, may be exemplary
and should not be treated as a limitation to the scope of the
current disclosure. It may also be contemplated that the system 114
may include a fiber optic cable assembly having multiple fiber
optic cables received within a jacket.
[0037] FIG. 4 shows a perspective view of an arrangement of the
fiber optic cable 302 to determine a position of the implement 106,
according to another aspect of the current disclosure. The first
end 304 of the fiber optic cable 302 may be disposed at any
position on the beam 105. The fiber optic cable 302 may then extend
to the first lift arm 136 and coupled along an outer surface
thereof. The fiber optic cable 302 may then extend to the first
linear actuator 146 and coupled to the first lift arm 136. The
fiber optic cable 302 may be wound around the cylinder 152 and the
piston rod 154 and then coupled with the third leg 126. As shown in
FIG. 4, the fiber optic cable 302 may extend to the center of the
third leg 126. In another aspect of the current disclosure, the
fiber optic cable 302 may extend to the first linear actuator 146
and coupled to the second lift arm 138. The fiber optic cable 302
may be then coupled with the third leg 126 and extend to the center
of the third leg 126. In the illustrated aspect of the current
disclosure, the fiber optic cable 302 may then extend through the
circle member 160, substantially along the axis A1, from the center
of the third leg 126. The fiber optic cable 302 may then travel
along the arm portion 164 and coupled thereto. Alternatively, the
fiber optic cable 302 may extend perpendicularly from the center of
the third leg 126 and coupled with the outer circumference 162 of
the circle member 160.
[0038] The fiber optic cable 302 may be coupled along the surface
314 of the arm portion 164. The fiber optic cable 302 may then
travel to the bottom end 316 of the arm portion 164. From the
bottom end 316, the fiber optic cable 302 may be wound around the
piston rod 184 of the fourth linear actuator 180 and extend to the
location 318 where the piston rod 184 is mounted on the blade 108.
Thus, the second end 306 of the fiber optic cable 302 may be
coupled adjacent to the location 318 of the piston rod 184 with the
blade 108. In another aspect of the current disclosure, the second
end 306 may be coupled to any location of the blade 108 to monitor
the position of the implement 106. The fiber optic cable 302 may
further configured to selectively generate signals indicative of a
shape thereof.
[0039] The placement of the fiber optic cable 302 in the beam 105,
the actuation system 112 and the implement 106, as shown in FIGS. 2
and 4, are exemplary in nature. Various alternative placements of
the fiber optic cable 302 may be contemplated within the scope of
the current disclosure in order to monitor the positions and
orientations of the implement 106 and/or components of the
actuation system 122. It may also be contemplated that one or more
slacks may be provided along the length of the fiber optic cable
302 in order to facilitate movement of the fiber optic cable 302
with the movement of the implement 106 and various components of
the actuation system 112.
[0040] FIG. 5 shows a block diagram illustrating the system 114 for
determining the position of the implement 106, according to an
aspect of the current disclosure. The system 114 may include the
controller 150 configured to be in communication with the fiber
optic cable 302. The controller 150 may be disposed in the operator
cab 110. Alternatively, the controller 150 may be located at any
location of the motor grader 100. The first end 304 of the fiber
optic cable 302 may be in communication with the controller 150. In
another aspect of the current disclosure, the controller 150 may
also be in communication with the second end 306. The controller
150 may be further configured to determine the shape of the fiber
optic cable 302 based on the signals received therefrom through the
first end 304. The controller 150 may be further configured to
determine a position of the implement 106 and the actuation system
112 relative to the front frame 102 based on the shape of the fiber
optic cable 302.
[0041] In another aspect of the current disclosure, the controller
150 may be a microprocessor based controller. The controller 150
may include one or more microprocessors configured to process
various input signals received from the fiber optic cable 302. More
specifically, a receiver of the controller 150 may be configured to
selectively receive optical signal corresponding to each of the
strain sensors 214. Further, a transmitter of the controller 150
may be configured to transmit an optical signal to the fiber optic
cable 302 in order to receive feedback from the strain sensors 214.
The controller 150 may be configured to generate various outputs
based on the input signals. The outputs of the controller 150 may
be further communicated to a display module 151. One of the outputs
may include a graphical representation of a three dimensional shape
of the fiber optic cable 302, which will be described in detail
with reference to FIGS. 6 and 7. The display module 151 may be
disposed in the operator cab 110 to show the output to an operator.
In another aspect of the current disclosure, the controller 150 may
be configured to automatically regulate the actuation system 112 in
order to achieve a desired position and/or orientation of the
implement 106. In an example, the controller 150 may determine the
position and/or orientation of the implement 106 and one or more
components of the actuation system 112, such as the drawbar member
120, the circle member 160 etc., based on the shape of the fiber
optic cable 302. Accordingly, the controller 150 may regulate the
actuation system 112. The controller 150 may further include a
memory configured to store various predetermined values, lookup
tables and algorithms required to perform various functions.
[0042] FIG. 6 shows an output 600 of the system 114, according to
an aspect of the current disclosure. The output 600 may correspond
to an exemplary shape of the fiber optic cable 302 based on the
position and/or orientation of the actuation system 112 and the
implement 106 shown in FIG. 2. The controller 150 in communication
with the fiber optic cable 302 may receive input signals from the
strain sensors 214. Each of the strain sensors 214 may provide a
signal indicative of a strain of a corresponding location of the
fiber optic cable 302 upon receipt of the optical signal from the
controller 150. The strain detected by each of the strain sensors
214 may correspond to bending and/or twisting of the fiber optic
cable 302 at the respective location. A position of the strain
sensors 214 may be determined with respect to a reference system,
for example, a Cartesian coordinate system. An X-axis of the
Cartesian coordinate system may correspond to the second axis A2,
while an Y-axis may correspond to the first axis A1. An Z-axis may
represent a longitudinal axis of the motor grader 100. In another
aspect of the current disclosure, a position of the strain sensor
214 located adjacent to the front end 111 of the beam 105 may be
determined as a first position point 602 of the fiber optic cable
302. In yet another aspect of the current disclosure, the strain
sensor 214 located adjacent to the controller 150 may be determined
as the first position point 602 of the fiber optic cable 302. The
first position point 602 of the fiber optic cable 302 may
correspond to the origin of the Cartesian coordinate system.
Alternatively, the origin of the Cartesian coordinate system may
correspond to the front end 111 of the beam 105. The controller 150
may further compute locations of the subsequent strain sensors 214
with respect to the first position point 602 based on the signals
received from the respective strain sensors 214. In an exemplary
aspect of the current disclosure, a position of each sensor segment
of the fiber optic cable 302 may be determined based on the signal
received from the corresponding strain sensors 214 and comparing
the corresponding strain with the strain of adjoining sensor
segments. The sensor segment may be defined as a portion of the
core 210 between two adjacent strain sensors 214. Thus, the
position of the sensor segments may be combined to determine the
position, shape and orientation of the fiber optic cable 302.
[0043] A portion of the fiber optic cable 302 extending along the
drawbar member 120 may lie substantially in a X-Z plane. The X-Z
plane may be substantially parallel to a ground surface. Hence, the
output 600 may indicate that a plane defined by the drawbar member
120 may be parallel to the ground surface. The output 600 may
further include a first point C1 and a second point C2 along the
length `L` of the fiber optic cable 302. The first point C1 may be
defined along the fiber optic cable 302 in order to determine an
angular position of the circle member 160 relative to the drawbar
member 120. A portion of the fiber optic cable 302 extending
between the center of the third leg 126 and the arm portion 164 may
lie substantially along the X-axis with respect to the point C1.
Hence, the output 600 may indicate that the circle member 160 may
be in an angular position such that the blade 108 may be
substantially oriented along the second axis A2. The second point
C2 may be defined in the fiber optic cable 302 to determine a
position of the blade 108 relative to the retainer 172. Referring
to the output 600, a portion of the fiber optic cable 302 extending
between the bottom end 316 of the arm portion 164 and the fourth
linear actuator 180 may lie substantially along the Y-axis. The
fiber optic cable 302 lying along the Y coordinate may correspond
to a retracted position of the third linear actuator 174. Further,
a portion of the fiber optic cable 302 wound around the fourth
linear actuator 180 may define a length IF along the X-axis that
may extend between the location 318 and the second point C2. The
length IF of the fiber optic cable 302 may correspond to an
extended position of the piston rod 184.
[0044] In various aspects of the current disclosure, more than
three coordinates may be defined along the length of the fiber
optic cable 302 in order to monitor the position of the drawbar
member 120 relative to the beam 105, the circle member 160 relative
to the drawbar member 120 and the implement 106 relative to the
retainer 172.
[0045] FIG. 7 shows an output 700 of the system 114 corresponding
to the shape of the fiber optic cable 302 based on another
configuration of the actuation system 112 and the implement 106.
The portion of the fiber optic cable 302 extending along the
drawbar member 120 may be shifted from the X-Z plane at an angle
.beta.1. Such shifting of portion of the fiber optic cable 302 may
indicate movement of the first linear actuator 146 towards a
retracted position thereof along the first axis A1. In such a case,
a plane defined by the drawbar member 120 may be inclined with
reference to ground surface. Further, the portion of the fiber
optic cable 302 extending between the center of the third leg 126
and the arm portion 164 may shift from the X-axis to an angle
.beta.2 with respect to the first point C1. Such shifting of the
fiber optic cable 302 may correspond to an angular position of the
circle member 160 based on actuation of the electric motor.
Further, the portion of the fiber optic cable 302 extending between
the bottom end 316 of the arm portion 164 and the fourth linear
actuator 180 may shift from the Y-axis to an angle .beta.3 with
respect to the second point C2. Such shifting of the fiber optic
cable 302 may correspond to movement of the third linear actuator
174 towards an extended position thereof. Further, a reduced length
`L2` compared to the length `L1` of the fiber optic cable 302 may
correspond to movement of the fourth linear actuator 180 towards a
retracted position thereof. In such case, the blade 108 may move
linearly along the second axis A2 with respect to the retainer
172.
[0046] The outputs 600 and 700, as described above, are purely
exemplary in nature and the fiber optic cable 302 may attain
various other shapes based on relative movement between various
components of the actuation system 112. Further, the first and
second points C1, C2, as shown in FIGS. 6 and 7, are also
illustrative in nature. It may be contemplated to monitor the
position of any point along the fiber optic cable 302 in order to
determine the positions and orientations of the implement 106
and/or various components of the actuation system 112.
INDUSTRIAL APPLICABILITY
[0047] The current disclosure relates to the system 114 and a
method 800 of monitoring the position of the implement 106 of the
motor grader 100 relative to the front frame 102. The controller
150 of the system 114 may receive signals generated by the fiber
optic cable 302 and determine the position of the implement 106
based on the shape of the fiber optic cable 302.
[0048] FIG. 8 shows a flowchart of the method 800 of determining
the position of the actuation system 112 and the implement 106,
according to an aspect of the current disclosure. The method 800
may be described in detail with respect to various steps.
[0049] At step 802, the method 800 may include providing the fiber
optic cable 302 along at least the portion of the front frame 102,
the portion of the actuation system 112 and the portion of the
implement 106. In another aspect of the current disclosure, the
fiber optic cable 302 may be coupled with the beam 105, the drawbar
member 120, the circle member 160 and the fourth linear actuator
180 in order to monitor various positions of the implement 106.
Further, various positions of the actuation system 112 and the
circle member 160 may also be monitored. In another aspect of the
current disclosure, the fiber optic cable 302 may be coupled with
the beam 105, the first linear actuator 146, the circle member 160
and the fourth linear actuator 180 in order to monitor various
positions of the implement 106.
[0050] At step 804, the method 800 may include receiving signals
from the fiber optic cable 302. The controller 150 in communication
with the first end 304 of the fiber optic cable 302 may receive
signals therefrom. The receiver of the controller 150 may
selectively receive optical signal corresponding to each of the
strain sensors 214. Further, the transmitter of the controller 150
may be configured to transmit an optical signal to the fiber optic
cable 302 in order to receive strain from respective locations of
the strain sensors 214. The strain sensors 214 may transmit signals
indicative of bending and/or twisting of the fiber optic cable 302
at corresponding locations of the strain sensor 214.
[0051] At step 806, the method 800 may include determining the
shape of the fiber optic cable 302 based on the received signals.
The position of the strain sensor 214 located adjacent to the front
end 111 of the beam 105 may be determined as the first position
point 602 of the fiber optic cable 302. The controller 150 may
further determine locations of the subsequent strain sensors 214
with respect to the first position point 602. In another aspect of
the current disclosure, position of each of the sensor segments may
be determined based on the strain data received from the
corresponding strain sensors 214 and comparing the data with
adjoining segments. The data for each of the segments may be
combined to determine the position, shape and orientation of the
fiber optic cable 302.
[0052] At step 808, the method 800 may include determining the
position of the implement 106 relative to the front frame 102 based
on the shape of the fiber optic cable 302. The origin of the
Cartesian coordinate system corresponds to the first position point
602. The first position point 602 may correspond to the position of
the strain sensor 214 located in the fiber optic cable 302 adjacent
to the front end 111 of the beam 105. The shape and orientation of
the portion of the fiber optic cable 302 extending along the
drawbar member 120 may correspond to the position of the drawbar
member 120 relative to the front frame 102. Further, the shape and
orientation of the portion of the fiber optic cable 302 extending
between the center of the third leg 126 and the arm portion 164
with respect to the first point C1 may correspond to the angular
position of the circle member 160 relative to the drawbar member
120. Further, the shape and orientation of the portion of the fiber
optic cable 302 extending between the bottom end of the arm portion
164 and the fourth linear actuator 180 with respect to the second
point C2 may correspond to the angular position of the blade 108
relative to the retainer 172. Further, a variation in a length of
the fiber optic cable 302 between the second point C2 and the
location 318 may correspond to linear movement of the blade 108
with respect to the retainer 172.
[0053] Thus, the system 114 and the method 800 of the current
disclosure monitor various positions of the implement 106 relative
to the front frame 102. Specifically, linear movement of the blade
108 with respect to the retainer 172 and angular movement of the
blade 108 with respect to the bottom end 316 of the arm portion 164
may be monitored through the controller 150. Further, inclination
of the blade 108 about the first axis A1 and the longitudinal axis
may also be monitored. Further, the outputs 600, 700 generated by
the controller 150 may facilitate the operator to locate exact
position of the implement 106 relative to the front frame 102, and
hence the position of the implement 106 relative to the surface of
the ground.
[0054] Further, the fiber optic cable 302 attached to the actuation
system 112 and the implement 106 may travel through various
mechanical joints (E.g., the ball and socket joint between the beam
105 and the drawbar member 120) so that only a minimum portion of
the fiber optic cable 302 may be moved relative to another moving
portion of the fiber optic cable 302, for example, the portions of
the fiber optic cable 302 attached to the drawbar member 120 and
the circle member 160. Further, any malfunction in the movement of
the drawbar member 120, the circle member 160, the first linear
actuator 146, the second linear actuator 156, the third linear
actuator 174 and the fourth linear actuator 180 may be
identified.
[0055] While the current disclosure have been particularly shown
and described with reference to the aspects above, it will be
understood by those skilled in the art that various additional
aspects may be contemplated by the modification of the disclosed
machines, systems and methods without departing from the spirit and
scope of what is disclosed. Such aspects should be understood to
fall within the scope of the current disclosure as determined based
upon the claims and any equivalents thereof.
* * * * *