U.S. patent application number 12/638123 was filed with the patent office on 2010-06-17 for system and method for optical locomotive decoupling detection.
This patent application is currently assigned to GENERAL ELECTRIC COMPANY. Invention is credited to Rahul Bhotika, David Michael Davenport, John Erik Hershey, Kenneth Brakeley Welles, II.
Application Number | 20100148013 12/638123 |
Document ID | / |
Family ID | 43971385 |
Filed Date | 2010-06-17 |
United States Patent
Application |
20100148013 |
Kind Code |
A1 |
Bhotika; Rahul ; et
al. |
June 17, 2010 |
SYSTEM AND METHOD FOR OPTICAL LOCOMOTIVE DECOUPLING DETECTION
Abstract
An apparatus and method for indicating whether a coupler of a
locomotive is in a coupled or uncoupled state is provided. The
apparatus comprising: an optical sensor positioned on a portion of
the coupler, wherein the sensor provides a real-time signal
indicative of either a coupled or an uncoupled state of a coupler,
wherein the signal is transmitted wirelessly by a transmitter in
operable communication with the sensor. The method comprising:
providing a signal indicative of the presence or proximity of a
second coupler to the first coupler, the signal being provided by
an optical sensor configured to provide the signal as the state of
the coupler has changed; transmitting the signal wirelessly to a
controller; processing the signal with a control algorithm resident
upon the controller; and providing visually perceivable indication
of the position of the coupler.
Inventors: |
Bhotika; Rahul; (Albany,
NY) ; Welles, II; Kenneth Brakeley; (Scotia, NY)
; Hershey; John Erik; (Ballston Lake, NY) ;
Davenport; David Michael; (Niskayuna, NY) |
Correspondence
Address: |
GENERAL ELECTRIC COMPANY;GLOBAL RESEARCH
ONE RESEARCH CIRCLE, PATENT DOCKET RM. BLDG. K1-4A59
NISKAYUNA
NY
12309
US
|
Assignee: |
GENERAL ELECTRIC COMPANY
Schenectady
NY
|
Family ID: |
43971385 |
Appl. No.: |
12/638123 |
Filed: |
December 15, 2009 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
|
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11317067 |
Dec 23, 2005 |
|
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|
12638123 |
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Current U.S.
Class: |
246/1C |
Current CPC
Class: |
B61L 15/0054 20130101;
B61J 3/00 20130101; B61G 7/14 20130101 |
Class at
Publication: |
246/1.C |
International
Class: |
B61L 23/00 20060101
B61L023/00 |
Claims
1. An apparatus for indicating whether a first coupler of a
locomotive is in a coupled or an uncoupled state, the apparatus
comprising: a visual sensor positioned on a portion of the coupler,
wherein the sensor provides a real-time signal indicative of either
a coupled state or an uncoupled state, the coupled or uncoupled
state indicating a proximity or presence of a portion of a second
coupler within a receiving area of the first coupler.
2. The apparatus as in claim 1, wherein the signal is transmitted
wirelessly by a transmitter in operable communication with the
sensor.
3. The apparatus as in claim 1, wherein the signal provided by the
sensor is responsive to the wavelengths of light outside of the
human-visible spectrum.
4. The apparatus as in claim 1, wherein the visual sensor comprises
a charge-coupled device whose field-of-view includes the
coupler.
5. The apparatus as in claim 1, wherein the coupler comprises an
optical target configured to present a predetermined optical
pattern within the field-of-view of the visual sensor.
6. The apparatus as in claim 1, wherein the coupler includes a
predetermined optical pattern within the field-of-view of the
visual sensor.
7. The apparatus as in claim 6, wherein the predetermined optical
pattern is disposed upon the coupler using a surface treatment.
8. The apparatus as in claim 7, wherein the surface treatment is
fluorescent and the apparatus includes an illumination source whose
emitted wavelengths of light are in the ultraviolet spectrum.
9. The apparatus as in claim 1 further comprising a control
algorithm for determining whether the coupler is in a coupled or an
uncoupled state.
10. A system for detecting whether a coupler of a locomotive is
coupled to another rail car, the system comprising: a sensing
device configured to provide a signal indicative of a coupling
state of the coupler; a wireless transmitter in operable
communication with the sensing device, the wireless transmitter
being configured to receive and transmit the signal; and a status
detection system configured to receive the signal from the wireless
transmitter, the status detection system comprising: a controller
including image processing algorithms for determining whether the
video signals depict a coupled or uncoupled locomotive; and a
storage medium, wherein the sensing device is a video camera
configured to provide video signals to the controller.
11. The system as in claim 10, further comprising an illumination
source configured to illuminate the coupler.
12. The system as in claim 11, wherein the illumination source
provides illumination wavelengths outside of the human-visible
spectrum.
13. The system as in claim 10, further including an optical target
disposed upon the coupler and having a predetermined optical
pattern.
14. The system as in claim 10, wherein the coupler includes a
predetermined optical pattern within the field-of-view of the
visual sensor.
15. The system as in claim 14, wherein the predetermined optical
pattern is disposed upon the coupler using a surface treatment.
16. The system as in claim 15, wherein the surface treatment is
fluorescent and the system further comprises an illumination source
whose emitted wavelengths of light are in the ultraviolet
spectrum.
17. The system as in claim 10, further comprising: a display
device, wherein the controller is configured to provide a graphical
indication of the coupling state on the display device, wherein the
graphical indication provides real time status of the
locomotive.
18. A method for determining whether a coupler of a locomotive
engine is coupled, the method comprising: configuring a video
camera to provide video signals indicative of either a coupled or
uncoupled state of the coupler; transmitting the video signals
wirelessly to a controller; processing the video signals with a
control algorithm resident upon the controller; and providing
visually perceivable indication of the coupled or uncoupled state
of the coupler.
19. The method as in claim 18, further comprising: programming the
controller with image processing algorithms for determining whether
the video signals depict a coupled or uncoupled locomotive.
20. The method as in claim 18, further comprising: disposing an
optical target having a predetermined optical pattern upon the
coupler.
21. The method as in claim 20, further comprising: illuminating the
coupler with a light source.
22. The method as in claim 21, wherein the light source provides
illumination wavelengths outside of the human-visible spectrum.
Description
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] This application is a continuation-in-part of co-pending
U.S. patent application Ser. No. 11/317,067 entitled "SYSTEM AND
METHOD FOR DETERMINING WHETHER A LOCOMOTIVE OR RAIL ENGINE IS
COUPLED TO A RAIL CAR OR OTHER ENGINE", filed on 23 Dec. 2005, the
entirety of which is incorporated by reference herein.
TECHNICAL FIELD
[0002] The systems and techniques described herein relate generally
to rail yards, and more particularly to methods and apparatus for
determining whether a train engine is coupled to a rail car.
BACKGROUND
[0003] Rail yards are the hubs of railroad transportation systems.
Therefore, rail yards perform many services, for example, freight
origination, interchange and termination, locomotive storage and
maintenance, assembly and inspection of new trains, servicing of
trains running through the facility, inspection and maintenance of
railcars, and railcar storage. The various services in a rail yard
compete for resources such as personnel, equipment, and space in
various facilities so that managing the entire rail yard
efficiently is a complex operation.
[0004] The railroads in general recognize that yard management
tasks would benefit from the use of management tools based on
optimization principles. Such tools use a current yard status and a
list of tasks to be accomplished to determine an optimum order in
which to accomplish these tasks.
[0005] However, any management system relies on credible and timely
data concerning the present state of the system under management.
In most rail yards, the current data entry technology is a mixture
of manual and automated methods. For example, automated equipment
identification (AEI) readers and AEI computers determine the
location of rolling stock at points in the sequence of operations,
but in general, this information is limited to data indicating
rolling stock whereabouts at particular times only, such as the
moment at which the rolling stock arrived, the moment at which the
rolling stock passes the AEI reader, and the moment at which the
rolling stock departs.
[0006] The location of assets within a rail yard is typically
reported using voice radio communications. Point detection
approaches such as wheel counters, track circuits, and automatic
equipment identification (AEI) tag readers have been used to detect
assets at specific, discrete locations on the tracks. Modern remote
control systems use GPS and AEI tags to prevent the
remote-controlled locomotive from traveling outside the yard
limits. Cameras have been deployed throughout rail yards with
shared displays to allow rail yard personnel (i.e. yard masters,
hump masters, manager of terminal operations) to locate engines and
other assets.
[0007] In particular, rail yard operators couple and uncouple rail
cars as they enter, leave and traverse through the rail yard. These
rail cars are coupled and uncoupled to train engines including
locomotive engines and yard engines. For example, operators can
uncouple rail cars from inbound locomotive engines and couple rail
cars to outbound locomotive engines. Further, yard engines can be
coupled to rail cars in order to transport the rail cars to
appropriate locations within the rail yard for loading, unloading,
or other processing.
[0008] Train engines in the rail yard can be tracked to determine
the progress of a task being performed, as well as to determine
whether the train engine(s) is/are being utilized efficiently. In
order to track engines at a rail yard, an operator can monitor the
coupling and decoupling of locomotive engines and yard engines
wherein information about the train status is provided via radio
communications. However, an operator-monitored system can be
inefficient in that it does not result in real time monitoring of
the train engine's status as such communication, if present, may be
exchanged well after the coupling or uncoupling event has
occurred.
[0009] For efficient rail yard operations it would be useful to
have an automatic system, which monitors the status of the yard
engines and provides real time data. In particular, real time data
indicating whether an engine is coupled or decoupled from a rail
car will provide insight as to the progress of rail yard
operations. In addition, rail yards may have many yard engines
actively working to process inbound trains and to build outbound
trains.
[0010] Therefore, yard operational efficiency may be realized by
the ability to automatically verify that an engine is coupled to
and moving one or more rail cars. Further benefits may be realized
by using yard engine operational status in yard planning tasks.
With automated, real-time knowledge as to operation of yard
engines, the yard operation team will be able to assess available
and utilized resources to plan subsequent tasks accordingly.
[0011] Accordingly, it is desirable to provide an apparatus and
system for indicating whether train engines are coupled or
decoupled from rail cars, wherein real time data is provided from
an automatic monitoring system.
SUMMARY
[0012] In one aspect of an exemplary apparatus for indicating
whether a first coupler of a locomotive is in a coupled or an
uncoupled state described herein, an optical or visual sensor is
positioned on a portion of the coupler. The sensor provides a
real-time signal indicating either a coupled state or an uncoupled
state, based on the presence of proximity or presence of a portion
of a second coupler within a receiving area of the first
coupler.
[0013] In an aspect of an exemplary system for detecting whether a
coupler of a locomotive is coupled to another rail car as described
herein, a sensing device, a wireless transmitter and a status
detection system are provided. The sensing device is configured to
provide a signal indicative of a couple state of the coupler, and
includes a video camera configured to provide video signals to a
controller of the status detection system. The wireless transmitter
is in operable communication with the sensing device and is
configured to receive and transmit the video signal from the
sensing device. The status detection system is configured to
receive the signal from the wireless transmitter and includes a
controller with image processing algorithms for determining whether
the video signals depict a coupled or uncoupled locomotive and a
storage medium.
[0014] In an aspect of an exemplary method for determining whether
a coupler of a locomotive engine is coupled as provided herein, a
video camera is configured to provide video signals indicative of
either a coupled or uncoupled state of the coupler. The video
signals are transmitted wirelessly to a controller. A control
algorithm resident in the controller processes the video signals,
and a visually perceivable indication of the coupled or uncoupled
state of the coupler is provided.
BRIEF DESCRIPTION OF THE DRAWINGS
[0015] These and other features, aspects, and advantages of the
described systems and techniques will become better understood when
the following detailed description is read with reference to the
accompanying drawings in which like characters represent like parts
throughout the drawings, and wherein:
[0016] FIG. 1 is a schematic illustration of a monitoring system in
accordance with exemplary embodiments described herein;
[0017] FIGS. 2, 2A and 2B are views illustrating couplers
constructed in accordance with exemplary embodiments described
herein;
[0018] FIG. 3 is a top plan view of a pair of couplers in a coupled
state;
[0019] FIG. 4 is a view of a sensing device in accordance with an
exemplary embodiment described herein;
[0020] FIG. 5 is a graphical representation of output signals of a
pair of sensors in accordance with an exemplary embodiment
described herein;
[0021] FIG. 6 is a graphical representation of output signals in
accordance with an alternative exemplary embodiment described
herein;
[0022] FIGS. 7-9 are illustrations of an alternative exemplary
embodiment;
[0023] FIG. 10 is a schematic illustration of yet another
alternative exemplary embodiment; and
[0024] FIG. 11 is a schematic illustration of a rail yard.
DETAILED DESCRIPTION
[0025] Exemplary embodiments of the systems and techniques
described herein are directed to a system and method for robust
determination of a locomotive's coupler status. In general, yard
engines or locomotives are dedicated to moving road locomotives or
other rail cars (e.g., cars that are pushed or pulled by
locomotives) to and from different service and staging areas of a
rail yard. Accordingly, it is desirable to know when a yard engine
is coupled to a rail car or road locomotive. In accordance with an
exemplary embodiment, sensors are provided to determine both a
coupled state and an uncoupled state of the locomotive. The sensor
output is conveyed over a wireless network to a control and
monitoring system. In one exemplary embodiment the coupler sensor
data may be combined with other data such as speed and direction of
motion of the locomotive, which can also be provided wirelessly.
This information allows assessment and utilization of the
locomotive. Furthermore, the coupler status can be used to monitor
progress in completion of assigned tasks and planning of subsequent
tasks, thereby increasing productivity of rail yard operations.
[0026] Reference is made to the following patent application Ser.
No. 10/360,055, filed: Feb. 6, 2003, the contents of which are
incorporated herein by reference thereto.
[0027] Referring now to FIGS. 1 and 2, a monitoring system 10 for
use with a railroad locomotive 12 is illustrated. The control
system utilizes a sensor or sensors 14 to determine whether a
coupler 16 of a locomotive or engine 12 is coupled to another
coupler 18 of a rail car 20. In an exemplary embodiment sensor 14
is in operable communication with a transceiver (e.g., receiver and
transmitter) or a transmitter 22 configured to transmit a signal 24
indicative of the coupled state of coupler 16.
[0028] In addition, a status detection system 26 is provided
wherein a receiver or transceiver 28 is in operable communication
with a controller 30. Receiver or transceiver 28 is configured to
receive signal 24 and provide the same to controller 30 wherein
controller 30 is configured to analyze one or more input signals
from sensors 14 and to produce one or more appropriate output
signals for use in yard management. The controller may be in the
form of a microcomputer, microcontroller, or other programmable
control device as either a separate component or integral part of a
rail yard operating system. As such, the controller may be any
known type of analog or digital device, and it may be embodied as
hardware, software or firmware.
[0029] The status detection system further includes a storage media
32 such as nonvolatile memory to store the control program
instructions for the controller and other data used by system 10.
Furthermore, the status detection system includes a display device
34 such as a computer monitor or screen to indicate train location
and movements on a graphical representation of the rail yard,
wherein and in an alternative exemplary embodiment the graphical
display will include train locations, track locations and other
features of the rail yard being monitored by the system.
[0030] In addition, the act of "coupling" or the use of "coupling"
herein includes a completed connection and/or the contacting of
coupler devices of train engines and rail cars as they interact to
make up a coupling connection. In order to couple rail cars and
locomotives (or engines) a coupler is disposed on at least one end
of the same. There are several types of couplers known to those
skilled in the related arts one such source of the types of
couplers found are described in "The Railroad What It Is, What It
Does" by John H. Armstrong, 4th Edition, Simmons-Boardman Books
Inc., 1998, page 106).
[0031] FIGS. 2, 2A and 2B illustrate a non-limiting example of a
coupler device (16, 18) contemplated for use in various exemplary
embodiments. Each coupler device comprises a neck portion 38 having
a clasping portion or head portion 40 secured thereto. Clasping
portion 40 defines a throat portion or receiving area 42 configured
to receive a portion of another coupling device secured thereto.
The coupler also comprises a knuckle portion 44 pivotally mounted
to a portion of the clasping portion defining the throat portion.
Knuckle portion 44 is configured for pivotal movement between a
coupled portion and an un-coupled portion in order to clasp another
knuckle portion of another coupler therein.
[0032] In North America, the rail industry has standardized the use
of a swinging knuckle design, which employs the principle of
clasped hands. In order to automatically couple the couplers
together, one or both of the knuckles must be open when the rail
cars with the couplers are pushed together, wherein an open knuckle
is moved (pushed) into a closed position by the second coupler
device and a locking device 46 drops downward to keep the knuckle
in this position and hold it closed. To uncouple the couplers, the
cars are pushed together such that the load is removed from the
coupler and an uncoupling lever 48 of the locking device is raised
by an operator, who lifts a lock pin 50, which allows the knuckle
to swing open as the car and engine are pulled apart. An
illustration of two couplers coupled together is shown in FIG.
3.
[0033] Conditions incident to coupling include approaching railcar
20 (FIG. 1) (the approach) actual contact with the railcar (the
impact) and the various resulting effects of the impact (the
effect). Information representative of these conditions can be
identified, recorded and provided to monitoring system 10 through
various sensors 14. In addition, the act of "coupling" as that term
is used in this herein includes a completed connection and/or the
contacting of the coupler devices as they interact to make up the
coupling connection, as appropriate for the context of the
description.
[0034] In addition and as used herein, "uncoupling" is defined as
the absence of a connection between coupler devices or the opening
and separation of coupler devices. It should be noted that
uncoupling does not involve an impact such as that resulting from
the coupling event (when locomotive is brought into contact with
the rail car at speeds typically less than four miles per
hour).
[0035] In accordance with an exemplary embodiment, sensors 14 are
installed on couplers at each end (forward and rear) of a
locomotive (or yard engine). The output of these sensors is
conveyed using wireless network from the locomotive to a central
control location (i.e. monitoring location) wherein the status
detection system is located. In addition to the coupler sensors,
the speed and direction of motion of the locomotive may also be
conveyed to the central control location. Speed and direction may
be obtained using GPS receiver or other devices 60 also equipped
with a transceiver or transmitter 62 to at least transmit a speed
and direction signal 64 to the transceiver of the status detection
system.
[0036] In accordance with exemplary embodiments described herein
the sensing of the couplers is implemented using one or more of the
following approaches: proximity sensors embedded within the knuckle
or throat of the coupler device; one or more strain gauge sensors
affixed to the coupler neck; a magnetic circuit; and an optical or
visual detection system comprising a camera and computer vision
system or any other equivalent device capable of providing a
real-time signal or signals indicative of coupler status.
[0037] Referring now to FIG. 3, an exemplary embodiment comprising
one or more inductive proximity sensors 70 embedded within the
knuckle or throat of the coupler device is illustrated. Here an
industrial proximity sensor is located in the coupler body with its
active end at the throat wherein the presence of a knuckle on
another coupler in the throat triggers the sensor or causes the
sensor to provide an output signal. Such inductive proximity
sensors are commonly used within industrial environments to detect
presence of ferrous metals. One non-limiting example of such an
inductive proximity sensor is available from Turck, wherein
additional information is found at www.turck.com. Of course, other
inductive sensors are contemplated for use with exemplary
embodiments described herein. Accordingly, such a sensor will
respond to the presence of another steel knuckle in close proximity
to the sensor. In accordance with an exemplary embodiment and
referring now to FIGS. 4 and 5, multiple sensors 70 are used to
detect a coupled or uncoupled state regardless of the direction of
motion (i.e. pushing or pulling of the rail car).
[0038] FIG. 4 shows a non-limiting example as to where a pair of
proximity sensors 70 would be installed within a knuckle, each
sensor having their active end disposed to detect a portion of
another knuckle. While the proximity sensors could be installed in
the coupler neck or throat, installation of these sensors in the
knuckle affords rapid configuration and utilization as knuckles can
be changed by Carmen in a matter of minutes. Change of a coupler
neck, on the other hand, requires service within a locomotive
shop.
[0039] Referring now to FIG. 5, a graph of the sensors A and B are
shown for signals of various coupling states. In the absence of a
proximate metal, the proximity sensors will output a low (zero)
voltage level (state 72). Using the configuration of FIG. 4, one or
both proximity sensors will provide a high voltage level when
another knuckle and coupler are brought in contact during a
coupling event. Depending upon the relative position of the two
couplers and their knuckles, open space referred to as "slack", may
place the coupler components beyond the sensor detection range.
Under such a condition the sensors will not detect the coupled
state. This is illustrated as state 76. As the railcar is moved,
one or more of the proximity sensors will provide the high voltage
output regardless of the direction of the movement (i.e. push or
pull of the rail car). This is illustrated as states 70 and 80.
Uncoupling and separation is also illustrated as state 82 wherein
both sensors will provide an output. The location of the proximity
sensors is selected to accommodate potential misalignment of the
couplers, which is on the order of 10 degrees or less. Misalignment
is shown as "free slack" in FIG. 3. Furthermore, the proximity
sensors are selected to provide a detection distance for the metal
surfaces on the order of 3/8 inch (which represents half of the 3/4
inch cited as slack spacing for a pair of couplers in a nominal
condition). Of course, other configurations are contemplated in
accordance with exemplary embodiments described herein.
[0040] Referring back now to FIG. 5, wherein proximity sensor
outputs for various coupling conditions and car movements is
provided it is noted that during steady state the output levels
from the sensors depends upon the resulting slack and detection
distances of the proximity sensors. In accordance with an exemplary
embodiment, both coupling and uncoupling events appear on one or
both sensor outputs (state 74 and 82). Thus, and as the locomotive
moves, at least one of the proximity sensors is brought into
contact or near contact with the opposite knuckle or coupler as the
slack is pulled out from the cars. Accordingly, this output and
data as provided to the controller wherein further processing is
provided and the status of the yard engine or locomotive is
provided to the yard operator.
[0041] In an alternative embodiment and referring now to FIGS. 1, 2
and 6, one or more strain gauge sensors 86 are affixed to the
coupler neck. In this embodiment, the force on the neck is detected
by the sensor, which will indicate whether a load is either being
pushed or pulled by the locomotive. A non-limiting example of the
output from a strain gauge 86 installed on the coupler neck is
illustrated in FIG. 6. As shown, the force from the coupling event
translates to a positive output signal 88 from the sensor. As the
locomotive pushes or pulls the rail car (or another locomotive),
the forces produce non-zero output from the strain gauge.
Thereafter, FIG. 6 illustrates locomotive stoppage, locomotive
reversing, bounce from pulling, and steady pulling by the engine.
Thereafter, sensor outputs corresponding to reduced speed, breaking
and stopped train conditions are also illustrated. Accordingly,
each of these conditions are capable of being sensed by the strain
gauge sensor or sensors (in any type of order) wherein a sensor
provides an output signal in digital or analog format for further
interpretation by control algorithms of system 10.
[0042] In this embodiment, detection of an uncoupling event will
also require combination of engine motion (i.e. speed) information
from sensor 60. In other words, the uncoupling event will be
recognized only when the locomotive moves and the speed signal will
be the second signal required to show that the locomotive is moving
and uncoupled. Non-limiting examples of a strain gauges sensor
comprise a Wheatstone bridge and the output voltage is recorded
using a V-Link wireless data recorder by MicroStrain.
[0043] Referring now to FIGS. 7-9, another alternative exemplary
embodiment is illustrated. Here a magnetic signaling device 90 is
illustrated. In this embodiment and when the locomotive is coupled
to the car, there is a magnetic circuit of high average
permeability 94 that is defined by a closed path that runs from the
neck of one coupler through the adjacent coupler, through the
adjacent car frame, and returns through the rail to the other car
frame, and back to the point of origin on the original coupler's
neck. An effective air gap between the two couplers subsumes such
small distances as non-ferromagnetic iron oxide patina, oil
interfaces, etc. When the locomotive and the car are decoupled
(FIG. 7), the air gap portion of the magnetic circuit is
significantly increased, as the flux then passes through the air
from the coupler tip to the rails. This is illustrated as magnetic
circuit 94. In this embodiment the magnetic sensing device
comprises a means for differentiating between the coupled and
uncoupled states by sensing the change in average permeability of
the magnetic circuit.
[0044] As a very crude analysis: the inductance seen by the
magnetic circuit is proportional to the relative permeability,
.mu..sub.e, of the magnetic material in the circuit where,
.mu..sub.e is defined as .mu..sub.e=.mu./.mu..sub.0. .mu. is the
permeability (or "absolute permeability") of the material within
the magnetic circuit, in this case iron. With the air gap,
.mu..sub.e=.mu..sub.r/(1+(.mu..sub.rl.sub.g/l.sub.e)), where
.mu..sub.r is the relative permeability of the iron, and l.sub.g is
the length of the gap.
[0045] Consider that in the locomotive-car separated case, an air
gap of length l.sub.g in the magnetic circuit is approximated by
the effective length of flux line travel. In this case,
.mu..sub.e.apprxeq..mu..sub.r/(1+.mu..sub.r).apprxeq.1. If the
locomotive is in contact with the car, locomotive-car contact case,
we approximate l.sub.g.apprxeq.0 and .mu..sub.e.apprxeq..mu..sub.r.
The change in inductance between the locomotive-car separated case
and the locomotive-car contact case should be dramatic and this
change should be detectable in a number of ways.
[0046] One way of providing this sensing device is illustrated in
FIGS. 7-9, wherein the drawbar is surrounded with two electrical
coils 100 and 102 at different locations. A time-varying current is
passed through one coil that establishes a time-varying magnetic
field. The time-varying magnetic field induces a current in the
second coil. The magnitude of the induced current will be greater
for the coupled state. Thus, the coupled state will be
detected.
[0047] An alternative method for sensing the change in inductance
of the magnetic circuit is to use a single coil as part of an
inductance estimating circuit such, as a simple tuned-circuit
resonator.
[0048] Referring now to FIG. 10 yet another alternative exemplary
embodiment is illustrated. Here an optical or visual sensing system
120 with remote sensing capabilities is provided. In this
embodiment, a camera 122 is mounted on the end of the locomotive,
above and oriented at the coupler. The camera is coupled to a
transceiver 124 wherein video signals are provided to computer
vision algorithms resident upon the microprocessor of the status
detection system, wherein the vision algorithms are applied to the
incoming video stream to detect a coupled state or uncoupled state.
The image and computer processing algorithms can include such
techniques as pattern matching, edge detection, location of
recognized shapes or patterns within the visual field and such
other techniques that would be understood to be applicable to
discern the two states. The video camera may also include an
illumination source to provide enhanced operation during night and
inclement weather conditions. In some embodiments, an aperture
cleansing system may also be provided to remove dirt, grime or
other detritus that may interfere with the data capture capability
of the camera or other sensor.
[0049] The image processing techniques can include pattern matching
techniques that are used to identify specific visual signatures
that indicate visible features of the coupler. For example,
patterns identified with an open or closed state of a clasping
portion 40 of a coupler can be recognized. In addition, patterns
identified with the presence or absence of a portion of another
coupling device being within the receiving area 42 of a coupler can
also be identified. Such patterns may be identified in various,
such as identifying the edges present within the visual field and
using these edges to identify the configuration of the various
components of the coupler(s) within the optical field of view of
the camera.
[0050] When such optical recognition is based upon the geometry of
the couplers, no additional sensors or preparation may be required
in order for the system to properly recognize a coupled or
uncoupled state. This may be of particular advantage when the
system is in use with cars that are associated with various
entities that may not be affiliated with the locomotive, and which
may not have been prepared specifically to work with the optical
imaging system described herein.
[0051] However, various techniques are available which may be used
to enhance the operation of the system, both when recognizing
coupling events with specially prepared cars, as well as when
working with cars or engines that have not been specially prepared
for detection by the visual sensors described herein.
[0052] One example of such enhancement is through the use of
illumination of the couplers and the area within the field-of-view
of the optical sensors. Such illumination can be provided via a
light or other illumination source that is mounted on the
locomotive 12 or another rail car. The illumination may be provided
in a variety of wavelength ranges, but it will generally be
understood that it will be at least one of the provided
illumination wavelength ranges should overlap with the wavelengths
which the sensor is able to detect. Such ranges are not limited to,
but can include: the visible spectrum (which may also have
practical benefits in that such illumination is also of benefit to
yard workers, and may even already be present); the infrared
spectrum, particularly the near-infrared spectrum, for which many
common optical sensors (such as charge-coupled devices, or CCDs)
provide sensitivity; the ultraviolet spectrum; and any other range
that may be suitable.
[0053] The use of non-visible spectrum wavelengths may provide an
advantage where very high levels of illumination are required that
might cause difficulties for yard workers subject to such bright
lights. In addition, the use of non-visible wavelengths may provide
an ability to properly illuminate the desired area at night without
damaging the night-vision of yard workers.
[0054] Light enhancement techniques may also be used either in
place of, or in addition to, illumination. Such enhancement
techniques may include the use of ambient light enhancement, such
as with photomultiplier tubes sensitive to photons of appropriate
wavelengths. The application of materials which respond to
particular types of illumination, such as fluorescent materials,
may also be used to increase the definition of the geometry within
the optical field-of-view when properly illuminated.
[0055] Ordinary reflective materials may also be suitable for
improving the definition within the visual field and enhancing the
ability of the visual sensor to detect specific geometry patterns
associated with a coupled or uncoupled state. In addition to such
visual reflectivity enhancements, specific predetermined patterns
may be placed on or near the coupler of either or both of the
locomotive or the rail car to make detection of the presence and
state of the coupler easier.
[0056] Such patterns can be disposed upon the coupler or related
geometry using techniques described above, such as the use of
reflective or emissive (such as fluorescent) materials, or can be
disposed upon pre-made optical targets that can be attached to the
coupler of the locomotive or rail car. It will be recognized that
such patterns may be patterns that are more easily detected or
processed by the controller. The use of such targets may also be
effective to enhance detection in circumstances where the geometric
design of the coupler is different from that originally intended to
be recognized, or if limitations of the locomotive or rail car
geometry prevent a clear line of sight from the camera to the
couplers in the operative condition.
[0057] In addition, it will be recognized that in some embodiments,
the camera or other visual sensor may be disposed upon a rail car
other than a locomotive. It will also be understood that the
detection techniques described herein are not strictly limited to
detecting coupling between a locomotive and a rail car, but may be
used to determine a coupling status of two rail cars (when
appropriately equipped), between a rail car and a piece of rail
yard equipment other than a locomotive, or between any objects
being monitored that provide an appropriate coupling mechanism.
Examples of such objects may include without limitation tandem
trailers with appropriate couplers for use on roadways and tugboats
and/or barges.
[0058] In another embodiments of an optical sensor system, a visual
sensor, such as a camera is provided that includes a control
algorithm within the visual sensor. With electronics becoming ever
more inexpensive, powerful and environmentally hardened, and with a
general decrease in power consumption for electronic processing, an
appropriate control algorithm may be included within the camera
circuitry itself such that a determination as to whether a coupled
or uncoupled state is detected may be made within the camera or
other optical sensor at the point of detection.
[0059] This control algorithm may be executed on a controller which
may be part of the video camera, or otherwise disposed in
association with the camera, rather than being disposed at a remote
status detection system. In such embodiments, a signal indicating
the coupler's state (coupled or uncoupled) may be wirelessly
broadcast from the camera or other sensor system, rather than
transmitting the video signal for off-board processing in order to
make a coupling-state determination. In some embodiments, such an
embedded camera/controller could be configured such that the
processing is incorporated at the focal plane rather than in a
distinct controller component.
[0060] In accordance with various exemplary embodiments a robust
sensor for detecting coupled and uncoupled status of a locomotive
or yard engine is provided. As disclosed herein and in accordance
with an exemplary embodiment, wireless communication of the sensor
state is provided from the locomotive to a control (monitoring)
location.
[0061] In addition, the coupling detection of yard engines can be
used by yard personnel to plan and assign yard tasks as these
inputs can also be used to feed an automated monitoring system
which captures historical performance data as to task completion
for individual locomotives and their operators. Moreover, such an
automated monitoring system can also be used by yard personnel to
enhance their planning and overall yard productivity.
[0062] Accordingly, exemplary embodiments allow for fast, simple
and low cost methods of creating an accurate track location
database for a rail yard. A generic view of a rail yard is
illustrated in FIG. 11.
[0063] In accordance with an exemplary embodiment, the monitoring
system comprises at least a central computer, a rail track database
and sensors to provide real time data of rail yard assets for use
with the rail track database to provide a visual representation of
the assets as they move through the rail yard, which may include
various sub yards including but not limited to a receiving yard, a
classification yard, a storage and receiving yard, and a departure
yard. In accordance with an exemplary embodiment, the described
systems employ GPS receivers to provide accurate track placement of
locomotives on a status display. Exemplary embodiments provide
real-time location of rail yard assets to rail yard personnel in
order to enable time-critical decisions to be made relative to task
planning, safety and efficiency.
[0064] As described above, algorithms for implementing exemplary
embodiments can be embodied in the form of computer-implemented
processes and apparatuses for practicing those processes. The
algorithms can also be embodied in the form of computer program
code containing instructions embodied in tangible media, such as
floppy diskettes, CD-ROMs, hard drives, or any other
computer-readable storage medium, wherein, when the computer
program code is loaded into and executed by a computer and/or
controller, the computer becomes an apparatus for practicing the
described technique. Existing systems having reprogrammable storage
(e.g., flash memory) that can be updated to implement various
aspects of command code, the algorithms can also be embodied in the
form of computer program code, for example, whether stored in a
storage medium, loaded into and/or executed by a computer, or
transmitted over some transmission medium, such as over electrical
wiring or cabling, through fiber optics, or via electromagnetic
radiation, wherein, when the computer program code is loaded into
and executed by a computer. When implemented on a general-purpose
microprocessor, the computer program code segments configure the
microprocessor to create specific logic circuits.
[0065] These instructions may reside, for example, in RAM of the
computer or controller. Alternatively, the instructions may be
contained on a data storage device with a computer readable medium,
such as a computer diskette. Or, the instructions may be stored on
a magnetic tape, conventional hard disk drive, electronic read-only
memory, optical storage device, or other appropriate data storage
device. In an illustrative embodiment, the computer-executable
instructions may be lines of compiled C++ compatible code.
[0066] In accordance with exemplary embodiments the central control
unit may be of any type of controller and/or equivalent device
comprising among other elements a microprocessor, read only memory
in the form of an electronic storage medium for executable programs
or algorithms and calibration values or constants, random access
memory and data buses for allowing the necessary communications
(e.g., input, output and within the microprocessor) in accordance
with known technologies. It is understood that the processing of
the above description may be implemented by a controller operating
in response to a computer program. In order to perform the
prescribed functions and desired processing, as well as the
computations therefore, the controller may include, but not be
limited to, a processor(s), computer(s), memory, storage,
register(s), timing, interrupt(s), communication interfaces, and
input/output signal interfaces, as well as combinations comprising
at least one of the foregoing.
[0067] The various embodiments of detection systems and techniques
described above thus provide a way to achieve a determination as to
whether or not a locomotive is coupled to a rail car while at an
arbitrary location within a rail yard. These techniques and systems
also allow real-time detection of such coupling states even when a
particular rail car is not disposed at a monitored location.
[0068] Of course, it is to be understood that not necessarily all
such objects or advantages described above may be achieved in
accordance with any particular embodiment. Thus, for example, those
skilled in the art will recognize that the systems and techniques
described herein may be embodied or carried out in a manner that
achieves or optimizes one advantage or group of advantages as
taught herein without necessarily achieving other objects or
advantages as may be taught or suggested herein.
[0069] Furthermore, the skilled artisan will recognize the
interchangeability of various features from different embodiments.
For example, the use of near-infrared optical detection as
described with respect to one embodiment can be adapted for use
with optical targets having pre-determined patterns to enhance
detection and recognition as described with respect to another.
Similarly, the various features described, as well as other known
equivalents for each feature, can be mixed and matched by one of
ordinary skill in this art to construct additional systems and
techniques in accordance with principles of this disclosure.
[0070] Although the systems herein have been disclosed in the
context of certain preferred embodiments and examples, it will be
understood by those skilled in the art that the invention extends
beyond the specifically disclosed embodiments to other alternative
embodiments and/or uses of the systems and techniques herein and
obvious modifications and equivalents thereof. Thus, it is intended
that the scope of the invention disclosed should not be limited by
the particular disclosed embodiments described above, but should be
determined only by a fair reading of the claims that follow.
* * * * *
References